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What does a cat scan machine look like: CT Scan (CAT Scan) Procedure Side Effects, Purpose, CT vs. MRI


Body CT (CAT Scan)

Computed tomography (CT) of the body uses sophisticated x-ray technology to help detect a variety of diseases and conditions. CT scanning is fast, painless, noninvasive and accurate. In emergency cases, it can reveal internal injuries and bleeding quickly enough to help save lives.

Tell your doctor if there’s a possibility you are pregnant and discuss any recent illnesses, medical conditions, medications you’re taking, and allergies. You will be instructed not to eat or drink anything for a few hours beforehand. If you have a known allergy to contrast material, your doctor may prescribe medications to reduce the risk of an allergic reaction. Leave jewelry at home and wear loose, comfortable clothing. You may be asked to wear a gown.

What is CT Scanning of the Body?

Computed tomography, more commonly known as a CT or CAT scan, is a diagnostic medical imaging test. Like traditional x-rays, it produces multiple images or pictures of the inside of the body.

A CT scan generates images that can be reformatted in multiple planes. It can even generate three-dimensional images. Your doctor can review these images on a computer monitor, print them on film or via a 3D printer, or transfer them to a CD or DVD.

CT images of internal organs, bones, soft tissue, and blood vessels provide greater detail than traditional x-rays. This is especially true for soft tissues and blood vessels.

Using specialized equipment and expertise to create and interpret CT scans of the body, radiologists can more easily diagnose problems such as cancer, cardiovascular disease, infectious disease, appendicitis, trauma and musculoskeletal disorders.

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What are some common uses of the procedure?

CT imaging is:

  • one of the fastest and most accurate tools for examining the chest, abdomen and pelvis because it provides detailed, cross-sectional views of all types of tissue.
  • used to examine patients with injuries from trauma such as a motor vehicle accident.
  • performed on patients with acute symptoms such as chest or abdominal pain or difficulty breathing.
  • often the best method for detecting cancers in the chest, abdomen and pelvis, such as lymphoma and cancers of the lung, liver, kidney, ovary and pancreas. It’s considered the best method since the image allows a physician to confirm the presence of a tumor, measure its size, identify its precise location and determine the extent of its involvement with other nearby tissue.
  • an examination that plays a significant role in the detection, diagnosis and treatment of vascular diseases that can lead to stroke, kidney failure or even death. CT is commonly used to assess for pulmonary embolism (a blood clot in the lung vessels) as well as for aortic aneurysms.

In pediatric patients, CT imaging is often used to evaluate:

  • lymphoma
  • neuroblastoma
  • kidney tumors
  • congenital malformations of the heart, kidneys and blood vessels
  • cystic fibrosis
  • complications of acute appendicitis
  • complications of pneumonia
  • inflammatory bowel disease
  • severe injuries

Radiologists and radiation oncologists often use the CT examination to:

  • quickly identify injuries to the lungs, heart and vessels, liver, spleen, kidneys, bowel or other internal organs in cases of trauma.
  • guide biopsies and other procedures such as abscess drainages and minimally invasive tumor treatments.
  • plan for and assess the results of surgery, such as organ transplants or gastric bypass.
  • stage, plan and properly administer radiation treatments for tumors as well as monitor response to chemotherapy.
  • measure bone mineral density for the detection of osteoporosis.

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How should I prepare?

Wear comfortable, loose-fitting clothing to your exam. You may need to change into a gown for the procedure.

Metal objects, including jewelry, eyeglasses, dentures, and hairpins, may affect the CT images. Leave them at home or remove them prior to your exam. Some CT exams will require you to remove hearing aids and removable dental work. Women will need to remove bras containing metal underwire. You may need to remove any piercings, if possible.

Your doctor may instruct you to not eat or drink anything for a few hours before your exam if it will use contrast material. Tell your doctor about all medications you are taking and if you have any allergies. If you have a known allergy to contrast material, your doctor may prescribe medications (usually a steroid) to reduce the risk of an allergic reaction. To avoid unnecessary delays, contact your doctor well before the date of your exam.

Also tell your doctor about any recent illnesses or other medical conditions and whether you have a history of heart disease, asthma, diabetes, kidney disease, or thyroid problems. Any of these conditions may increase the risk of an adverse effect.

Women should always inform their physician and the CT technologist if there is any possibility that they may be pregnant. See the CT Safety During Pregnancy page for more information.

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What does the CT equipment look like?

The CT scanner is typically a large, donut-shaped machine with a short tunnel in the center. You will lie on a narrow table that slides in and out of this short tunnel. Rotating around you, the x-ray tube and electronic x-ray detectors are located opposite each other in a ring, called a gantry. The computer workstation that processes the imaging information is in a separate control room. This is where the technologist operates the scanner and monitors your exam in direct visual contact. The technologist will be able to hear and talk to you using a speaker and microphone.

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How does it work

In many ways, a CT scan works like other x-ray exams. Different body parts absorb x-rays in different amounts. This difference allows the doctor to distinguish body parts from one another on an x-ray or CT image.

A conventional x-ray exam directs a small amount of radiation through the body part under examination. A special electronic image recording plate captures the image. Bones appear white on the x-ray. Soft tissue, such as the heart or liver, shows up in shades of gray. Air appears black.

With CT scanning, several x-ray beams and electronic x-ray detectors rotate around you. These measure the amount of radiation being absorbed throughout your body. Sometimes, the exam table will move during the scan. A special computer program processes this large volume of data to create two-dimensional cross-sectional images of your body. The system displays the images on a computer monitor. CT imaging is sometimes compared to looking into a loaf of bread by cutting the loaf into thin slices. When the computer software reassembles the image slices, the result is a very detailed multidimensional view of the body’s interior.

Nearly all CT scanners can obtain multiple slices in a single rotation. These multi-slice (multidetector) CT scanners obtain thinner slices in less time. This results in more detail.

Modern CT scanners can image large sections of the body in just a few seconds, and even faster in small children. Such speed is beneficial for all patients. Speed is especially beneficial for children, the elderly, and critically ill – anyone who finds it difficult to stay still, even for the brief time necessary to obtain images.

For children, the radiologist will adjust the CT scanner technique to their size and the area of interest to reduce the radiation dose.

Some CT exams use a contrast material to enhance visibility in the body area under examination.

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How is the procedure performed?

The technologist begins by positioning you on the CT exam table, usually lying flat on your back. They may use straps and pillows to help you maintain the correct position and remain still during the exam.

Many scanners are fast enough to scan children without sedation. In special cases, children who cannot hold still may need sedation. Motion may cause blurring of the images and degrade image quality the same way that it affects photographs.

The exam may use contrast material, depending on the type of exam. If so, it will be swallowed, injected through an intravenous line (IV) or, rarely, administered by enema.

Next, the table will move quickly through the scanner to determine the correct starting position for the scans. Then, the table will move slowly through the machine for the actual CT scan. Depending on the type of CT scan, the machine may make several passes.

The technologist may ask you to hold your breath during the scanning. Any motion, including breathing and body movements, can lead to artifacts on the images. This loss of image quality can resemble the blurring seen on a photograph taken of a moving object.

When the exam is complete, the technologist will ask you to wait until they verify that the images are of high enough quality for accurate interpretation by the radiologist.

The CT examination is usually completed within 30 minutes. The portion requiring intravenous contrast injection usually lasts only 10 to 30 seconds.

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What will I experience during and after the procedure?

CT exams are generally painless, fast, and easy. Multidetector CT reduces the amount of time that the patient needs to lie still.

Though the scan is painless, you may have some discomfort from remaining still for several minutes or from placement of an IV. If you have a hard time staying still, are very nervous, anxious, or in pain, you may find a CT exam stressful. The technologist or nurse, under the direction of a doctor, may offer you some medication to help you tolerate the CT exam.

If the exam uses iodinated contrast material, your doctor will screen you for chronic or acute kidney disease. The doctor may administer contrast material intravenously (by vein), so you will feel a pin prick when the nurse inserts the needle into your vein. You may feel warm or flushed as the contrast is injected. You also may have a metallic taste in your mouth. This will pass. You may feel a need to urinate. However, these are only side effects of the contrast injection, and they subside quickly.

If you swallow oral contrast material, you may find the taste mildly unpleasant. However, most patients can easily tolerate it. If you receive an enema, you can expect to experience a sense of abdominal fullness. You may also feel an increasing need to expel the liquid. If so, be patient; the mild discomfort will not last long.

When you enter the CT scanner, you may see special light lines projected onto your body. These lines help ensure that you are in the correct position on the exam table. With modern CT scanners, you may hear slight buzzing, clicking and whirring sounds. These occur as the CT scanner’s internal parts, not usually visible to you, revolve around you during the imaging process.

You will be alone in the exam room during the CT scan, unless there are special circumstances. For example, sometimes a parent wearing a lead shield may stay in the room with their child. However, the technologist will always be able to see, hear and speak with you through a built-in intercom system.

With pediatric patients, a parent may be allowed in the room but may need to wear a lead apron to minimize radiation exposure.

After a CT exam, the technologist will remove your intravenous line. They will cover the tiny hole made by the needle with a small dressing. You can return to your normal activities immediately.

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Who interprets the results and how do I get them?

A radiologist, a doctor specially trained to supervise and interpret radiology exams, will analyze the images. The radiologist will send an official report to the doctor who ordered the exam.

You may need a follow-up exam. If so, your doctor will explain why. Sometimes a follow-up exam further evaluates a potential issue with more views or a special imaging technique. It may also see if there has been any change in an issue over time. Follow-up exams are often the best way to see if treatment is working or if a problem needs attention.

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What are the benefits vs. risks?


  • CT scanning is painless, noninvasive, and accurate.
  • A major advantage of CT is its ability to image bone, soft tissue, and blood vessels all at the same time.
  • Unlike conventional x-rays, CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, and blood vessels.
  • CT exams are fast and simple. In emergency cases, they can reveal internal injuries and bleeding quickly enough to help save lives.
  • CT has been shown to be a cost-effective imaging tool for a wide range of clinical problems.
  • CT is less sensitive to patient movement than MRI.
  • Unlike MRI, an implanted medical device of any kind will not prevent you from having a CT scan.
  • CT imaging provides real-time imaging, making it a good tool for guiding needle biopsies and needle aspirations. This is particularly true of procedures involving the lungs, abdomen, pelvis, and bones.
  • A diagnosis via CT scan may eliminate the need for exploratory surgery and surgical biopsy.
  • No radiation remains in a patient’s body after a CT exam.
  • The x-rays used for CT scanning should have no immediate side effects.


There is no conclusive evidence that radiation at small amounts delivered by a CT scan causes cancer. Large population studies have shown a slight increase in cancer from much larger amounts of radiation, such as from radiation therapy. Thus, there is always concern that this risk may also apply to the lower amounts of radiation delivered by a CT exam. When a CT scan is recommended by your doctor, the expected benefit of this test outweighs the potential risk from radiation. You are encouraged to discuss the risks versus the benefits of your CT scan with your doctor or radiologist, and to explore whether alternative imaging tests may be available to diagnose your condition.

  • The radiation dose for this procedure varies. See the Radiation Dose in X-Ray and CT Exams page for more information about radiation dose.
  • Women should always tell their doctor and x-ray or CT technologist if there is any chance they are pregnant. See the Safety in X-ray, Interventional Radiology and Nuclear Medicine Procedures page for more information about pregnancy and x-rays.
  • Doctors do not generally recommend CT scanning for pregnant women unless medically necessary because of potential risk to the unborn baby.
  • IV contrast manufacturers indicate mothers should not breastfeed their babies for 24-48 hours after contrast material is given. However, the most recent American College of Radiology (ACR) Manual on Contrast Media reports that studies show the amount of contrast absorbed by the infant during breastfeeding is extremely low. For further information please consult the ACR Manual on Contrast Media and its references.
  • The risk of serious allergic reaction to contrast materials that contain iodine is extremely rare, and radiology departments are well-equipped to deal with them.
  • Because children are more sensitive to radiation, they should have a CT exam only if it is essential for making a diagnosis. They should not have repeated CT exams unless necessary. CT scans in children should always be done with low-dose technique.

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What are the limitations of CT Scanning of the Body?

Soft-tissue details in areas such as the brain, internal pelvic organs, and joints (such as knees and shoulders) can often be better evaluated with magnetic resonance imaging (MRI). In pregnant women, while CT can be performed safely, other imaging exams not involving radiation, such as ultrasound or MRI, are preferred but only if they are likely to be as good as CT in diagnosing your condition.

A person who is very large may not fit into the opening of a conventional CT scanner. Or, they may be over the weight limit—usually 450 pounds—for the moving table.

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Which test, procedure or treatment is best for me?

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This page was reviewed on April, 10, 2018

What’s the Difference Between an MRI and a CT?

Your doctor says you need a scan and immediately visions of a large machine fill your head. But do you know what you’re really in for when you need a CT or an MRI? It’s easy to get the two confused, especially if you’ve never had MRI or CT imaging done before. But from your perspective, lying on the table, there is a big difference! In this video, find out what each type of scan is like including how long it takes, why it’s used and how it works. That way, before you show up for your imaging appointment, you’ll know just what to expect:

What is an X-ray?

X-ray uses a small amount of radiation that passes through the body to quickly capture a single image of your anatomy to assess injury (fractures or dislocations) or disease (bone degeneration, infections or tumors). Dense objects, such as bone, block the radiation and appear white on the X-ray picture. Radiologists review the pictures and create a report with their findings to aid in diagnosis.

X-ray is good for:

  • Assessing injury (see X-ray scan of the hand to the right)
    Offering a low-cost, first-look exam

What is a CT/CAT Scan?

Wondering what the difference is between a CT and a CAT Scan. Nothing! They’re the same thing and you can use the names interchangeably. If you need a CT scan, you’re in luck, Traci says. In all her years of scanning, she’s never had a single patient who couldn’t handle a CT:

“Sometimes patients are a little bit uncomfortable in the positions we need them to hold but we’re usually able to get the scan done so quickly it’s never been a problem. Many people seem relieved that it is as easy to do as it is.”

In layman’s terms, CT is an X-ray machine that’s hooked up to a computer. You lie flat on the table and a pencil-thin beam takes cross-sectional images of your body. Traci explains that the beam rotates around your body and takes image slices of you like a loaf of bread.

CT does use radiation to capture clear images. At RAYUS, we do everything we can to make sure you are getting the lowest dose of radiation possible while still getting the highest quality images (to find out how that works, click here). The CT scan is so quick Traci says most patients’ worries about radiation exposure quickly disappear:

“It’s hard to be concerned when I explain to the patient: I’m going to ask you to hold still it’s going to be 3 minutes and I’m going to pull you right back out. I think for that reason the whole concern kind of goes away.”

CT is good for:

  • Imaging bone, soft tissue and blood vessels at the same time
  • Pinpointing issues with bony structures (injuries)
  • Evaluating lung and chest issues (see lung scan image to the right)
  • Detecting cancers
  • Imaging patients with metal (no magnet)

What is an MRI Scan?

MRI stands for Magnetic Resonance Imaging. MRI uses a powerful magnetic field, radio frequency pulses and a computer to produce images of your organs, soft tissue, bone and internal structures. As a patient, you’ll lie on a table that will slide into the machine. Traditionally the space where you would go into the MRI machine was a tube or tunnel, but these days there are many options including the Wide-bore MRI, the Open MRI and the Open Upright MRI machines which give you more breathing room during your exam.

Another piece of the MR equipment is the coil. The coil acts as an antenna for the radio frequency pulses and helps the machine gather the images of a particular part of your body. The coil might be a frame that snaps over your head or shoulder, it might be placed on the table before you lie down, or it could be wrapped with Velcro around the body part that’s being scanned. To learn more about coils and see what they look like, click here. Traci explains how an MR scan of your shoulder with a coil works:

“We place your shoulder into that coil and between the radio frequency, the strong magnetic field, and the coil, which acts as an antenna, we are going to produce images of the soft tissue and the bone, with MRI.”

Even if MR is the right scan for you – you might not be right for it. If you have ever had any metal in your body, such as a pacemaker, a spinal cord stimulator, a nerve simulator, an aneurysm clip, an ear implant, or a stent, it might not be safe for you to have an MR scan. Some newer implants are safe to take into an MRI scanner, but you’ll be asked a lot of questions when you book your appointment to make sure. Orthopedic metal in the bone (like a rod in a hip or shoulder) is always going to be safe.

MRI is good for:

  • Imaging organs, soft tissue an internal structures (see spine scan image to the right)
  • Showing tissue difference between normal and abnormal
  • Imaging without radiation

Understanding the Differences between MRI and CT

Seeing the differences laid out in a chart may help you understand how CT & MRI are unique. The shape of the machine is a major difference – CT is described as a “donut” while Traci tells her patients the MR machine is more like a “tanning bed”. CT uses radiation while MR does not. There’s also a significant difference in the length of the typical scan. Expect your MRI to take at least 30 minutes while a typical CT scan may take only 5 minutes. And while CT is great for looking at a tiny bone fracture or an organ, an MRI is better for looking at soft tissue like your brain. Remember, if you have a question about your scan, never be afraid to ask. Our technologists love to answer your questions and want you to feel relaxed and comfortable before, during and after your appointment.

Guiding Your Care

Our team of specialized radiologists and clinical associates are experts in imaging. They can help guide your provider in selecting the right technology for your exam depending on your unique situation. Our goal is to provide the finest in imaging services – the right procedure, at the right time, with accurate results for each individual patient.

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CT Scan: 5 Facts to Help You Prepare for Your Exam

A CT scan gives doctors a detailed view into your body, allowing them to diagnose a wide range of medical conditions as well as plan and monitor treatment. Learn five key facts about CT scans to help you prepare for your exam. And talk to your care provider about scheduling your CT scan at UVA Radiology and Medical Imaging.

1. A CT Scan Takes Images in Slices

A CT scan is state-of-the-art medical imaging that give doctors a detailed view into your body. CT scans, like x-rays, use ionizing radiation to create a set of images from many different angles. These images are like “slices” that, when put together, make a single, highly detailed image.

CT scans are used for anything from pinpointing the location of a tumor to checking for internal bleeding after trauma. Doctors use CTs to plan surgeries and other medical procedures as well as monitor conditions and treatments.

The “CT” in “CT scan” stands for computerized tomography. The scan is controlled by a computer, hence “computerized.” “Tomography” comes from the Greek word “tomos,” which means “slice” or “section.”

2. The Scanner Looks Like a Large Ring or Donut

CT (Computed tomography) scanner in hospital laboratory. Health care, medical technology, hi-tech equipment and diagnosis concept with copy space.

CT scans are performed by a radiologic technologist who will guide you through the whole procedure.

If you’re having a scan done, you’ll start by lying on the table attached to a CT machine. The CT machine looks like a large ring or donut big enough for you and the table to fit into. During the exam, the table slides into the hole, also called the bore, of the machine.

Once you’re in place, the internal parts of the CT machine will start to spin around you, but because of the machine’s casing you won’t be able to see this happening. You will, however, hear loud whirring noises as the internal parts spin around you. The CT machine may also move over you as it is scanning, depending on what body part is being scanned.

3. During the Scan, You’ll Have to Stay Still

Any movement during a CT could cause a blurry image, so you’ll need to stay still as possible. Even something as minor as breathing can affect the image. Depending on where the scan is focusing on, the technologist may ask you to briefly hold your breath.

Your scan could take anywhere between a few minutes to an hour. Using an intercom system, you’ll also be able to talk to the radiologic technologist at any time during the procedure if you experience any discomfort or anxiety.

4. Some CTs Require the Use of Contrast Dye

In certain cases, the CT scan may need to be performed after you’ve taken medical contrast dye. If contrast is needed, you’ll be asked take it orally or intravenously, depending on the procedure. This will increase how long the procedure takes because the contrast will need time to make its way through your body.

5. CT Scans Use Radiation, Like Traditional X-Rays

CT scans use radiation, which, in large enough doses, can raise a patient’s risk of cancer. But know that the risk of developing cancer from a CT is very low.

Remember that by ordering the exam, your doctor has determined that the risk from radiation is outweighed by the benefit of the exam. The information your doctor gains from a CT scan can help them make important diagnoses and plans for your treatment. Ultimately, a CT may provide critical information about your health.

If you’re concerned about being exposed to radiation, ask about other imaging exams that could be done as an alternative to a CT scan. And talk to your doctor to make sure you’re within the healthy range for lifetime radiation exposure. You can also use this online calculator to determine your lifetime radiation risk, or read our article on radiation.

Have Your CT Scan at UVA Health

Regardless of the specifics of your CT, the radiologists and radiologic technicians at UVA Radiology and Medical Imaging will do everything they can to make sure you have a good experience. They will work to explain the exam procedure to you, make you comfortable during the exam, minimize your radiation exposure, and provide clear and detailed results.

Ask your care provider to refer you to UVA Radiology and Medical Imaging for your CT scan. Call (434) 982-6600 to schedule a consultation or ask about an upcoming scan.

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CT Scan: 5 Facts to Help You Prepare for Your Exam was last modified: July 26th, 2021 by uvaradweb

CT vs MRI Scans | Florida Medical Clinic

The Difference Between a CT and a MRI Scan

If you’ve ever heard of a Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) machine, you may have wondered about the difference between the two. Both machines look nearly identical, since they each feature a round ‘donut’ and a movable bed where the patient is scanned. Both machines are designed to take images of selected, internal parts of the body. They are often even used on the same areas of the body!

What, then, is the difference between a CT and a MRI scan?

While MRI and CT scanners look similar and serve many of the same purposes, they are not the same machine.

CT Scans

CT scans utilize X-rays, which are radioactive, to capture individual image slices of the body. They are effective at making detailed images of the head, abdomen, chest, skeletal system, and more. CT scans are generally quieter and more comfortable for the patient, and faster than MRI scans.

MRI Scans

MRI scans utilize a combination of radio frequency pulses and strong magnetic fields to capture images of the body. While MRI scanners can also be used to make images of the head, abdomen, and chest just like a CT scanner, they do not scan bone. They are particularly effective at making images of soft tissue. No radiation is involved in an MRI scan, but they do take longer and are generally noisier.

Is One Type of Scan Better than the Other?

It depends. Both machines have their advantages and disadvantages. A lot of the deciding factor about which to use will boil down to the type of injury you have, as well as preference.

Advantages of CT Scans

  • Patients who have metal fragments or devices can use a CT scan because no magnetic field is involved.
  • Claustrophobic patients may find a CT scan more comfortable, as they are shorter and less noisy than a MRI.
  • CT scans are particularly good at imagining bones for accurate diagnosis of injury or disease.
  • CT scans are less sensitive to patient movement during the procedure.
  • With CT scans being faster than MRI, they are better to use during emergency situations.

Advantages of MRI Scans

  • MRIs do not use radiation, unlike CT scans, and are safe for use on patients who require multiple scans, and children.
  • MRIs are particularly good at imagining soft tissues. The radio frequency can even be adjusted to better highlight the tissue in question.
  • The scanning plane in an MRI can be adjusted without having to move the patient.
  • The type of contrast agent used for a MRI scan has a far lower chance of causing an allergic reaction in the patient.

Examples of Which Scanner Would be Used in Different Situations…

The list below is not comprehensive. Everyone’s situation is unique. Your doctor will know which is best for your particular situation.

  • Patients with spinal injury would use a CT scan as long as they don’t have metal implants.
  • Patients with internal bleeding or other injuries would use a MRI scan to obtain the best detail.
  • If a patient has a history of allergies, it may be best for them to use a MRI scan.
  • Claustrophobic patients may be able to better tolerate a CT scan since it has a shorter duration.

Common Questions about CT Scans

  • What does CT Scan stand for? ‘CT’ stands for Computed Tomography.
  • CT vs CAT scan – Is a CT Scan the Same as a CAT Scan? CT and CAT scans are the same thing. CAT stands for ‘computerized axial tomography’, and the term CT or CAT can be used interchangeably.
  • What Does a CT Scan Machine Look Like? CT and MRI scanners look very similar to each other. They both feature a ‘donut’ which houses the scanning equipment, and a bed which moves through the scanner. Both machines feature a communications system for the patient to speak with the technician. The type of system (microphone/headphone, integrated, etc,.) depends on the model of the particular machine.

If you’re curious about CT scans and how they work, check out our informational page here!

Florida Medical Clinic Radiology Department

The Florida Medical Clinic Radiology Department offers both CT and MRI scanning services. We are certified by the American College of Radiology (ACR), an accreditation which is only earned by achieving superior service and passing an intensive evaluation of the facility and staff.

Our radiologists and technologists are all licensed and certified. This means that not only can you have peace of mind during your procedure, you’ll receive the best quality scans and the most accurate evaluations of your imaging.

CT vs MRI: What’s the Difference? And How Do Doctors Choose Which Imaging Method to Use?


Radiologists use both CT and MRI to detect and monitor cancer. Each imaging method has strengths that make it appropriate for a particular reason. Learn how doctors choose which technique to use.

CT (computed tomography) and MRI (magnetic resonance imaging) are both used to diagnose and stage cancer. Many people do not know the difference between the two methods or why one might be selected over the other. Here, radiologist Richard Do answers some of the questions he gets from his patients about CT and MRI.

What is the difference between a CT scan and an MRI?

A CT scan uses X-rays to create detailed pictures of organs, bones, and other tissues. The person lies on a table that moves through a scanning ring, which looks like a large doughnut. The data collected can be assembled to form three-dimensional images. The images reveal abnormalities in both bone and soft tissues, such as pneumonia in the lungs, tumors in different organs, or bone fractures.

Richard Do

MRI also creates detailed pictures of areas inside the body, but it uses radio waves and a powerful magnet to generate the pictures. The person also lies on a table that moves into a doughnut-shaped device, but the doughnut is much thicker. Similarly, these pictures can show the difference between normal and diseased tissue.

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What are the advantages of CT?

With a CT scan, we can create an image of almost the entire body, from the neck to the thighs, in a few seconds. CTs are incredibly useful for diagnosing and staging cancer, checking whether it has come back, and monitoring whether a treatment is working. It’s very effective for surveying the entire body to look for places where the cancer has spread, such as the lungs, liver, or bone. These are called metastases. Most of the time, CT is the first choice to stage cancer.

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What are the advantages of MRI?

Where MRI really excels is showing certain diseases that a CT scan cannot detect. Some cancers, such as prostate cancer, uterine cancer, and certain liver cancers, are pretty much invisible or very hard to detect on a CT scan. Metastases to the bone and brain also show up better on an MRI.

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What are some disadvantages of each imaging method?

Because CTs use ionizing radiation, they could damage DNA and may very slightly raise the risk of developing cancer. The Food & Drug Administration estimates that the extra risk of any one person developing a fatal cancer from a typical CT procedure is about 1 in 2,000. MRIs do not use ionizing radiation, so there is no issue of raising cancer risk. But they take much longer to complete than CTs. MRIs require the person to lie still within a closed space for about 20 to 40 minutes. This can affect some people with claustrophobia, and the procedure is noisy, which is why we provide ear protection.

Both CT and MRI commonly require the injection of a contrast dye before or during the procedure. This helps the radiologist see organs and other tissues within the body more clearly.

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What concerns do people have about either imaging method?

For CT, I hear anxiety about exposure to radiation, especially if it is being done repeatedly. For example, certain early-stage cancers can be cured. But you might be coming back every few months or every year for a CT scan. The question is: Do we have an alternative? For detecting cancer that has come back throughout the body, a CT scan is preferable to an MRI. As radiologists, we follow a measure called “as low as reasonably achievable.” This means we give enough radiation to create CT images that are of high enough quality that we can make a good clinical decision, but we keep the radiation as low as possible to minimize risk.

For MRI, people who have trouble with claustrophobia or are unable to hold their breath, which may be required for certain abdominal imaging tests, may not be able to tolerate the procedure. Some MRI machines can be configured in ways that may reduce claustrophobia. Medical implants, such as a pacemaker, brain stimulator, or other devices, are another complicating factor. The radio waves used with MRI can heat up devices made of metal. This is potentially a concern for something inside the body. Newer medical devices are usually designed with this in mind, so they are safe inside an MRI.

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How do doctors decide which imaging a person should receive?

We usually use CT first for most people, unless a tumor is much better seen on MRI. But we go back and forth as needed. If we see something on a CT scan we’re unsure about, we may recommend an MRI for further evaluation. If someone has several MRIs and is unable to lie still or hold their breath so we can get a good image, we may suggest a CT as an alternative. We’re guided by the principle of whether the benefits of a test outweigh its risks. That’s what medical imaging is about.

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Computed Tomography (CT)

Breast CT scanner.
Credit: John Boone, UC Davis

Dedicated Breast CT Scanner: NIBIB is funding research for development of a dedicated breast CT scanner that allows the breast to be imaged in 3D and could help radiologists detect hard-to-find tumors. The scanner produces a radiation dose comparable to that of a standard x-ray mammogram and doesn’t require compression of the breast. In this breast CT scanner, a woman lies prone in a specially designed large table with her breast suspended in a special opening in the scanning bed. The scanner rotates around the breast, without passing through the chest, thus reducing the radiation that would be delivered to the chest in a conventional CT scanner. Listen to a podcast about the scanner.

Reduction in Radiation from Routine CT Scans: NIBIB put out a call for researchers to submit groundbreaking ideas that will help to radically decrease the amount of radiation used in CT scans. Five new projects are underway from this new funding opportunity, representing creative, innovative, interdisciplinary approaches that would not have been funded otherwise. You can read more about them below:

Customized imaging
Web Stayman, Johns Hopkins University
The amount of radiation required for a CT scan depends on a number of variables, including the size of the patient, the part of the body being scanned, and the diagnostic task at hand. For example, smaller patients require less radiation than larger patients, and scanning a denser part of the body, such as soft tissue near the pelvis, requires more radiation than scanning the lungs. In addition, diagnostic tasks that require high image clarity, such as locating a faint tumor, generally require more radiation. The goal of this project is to modify both the hardware and software of modern CT systems so that the device can adapt the shape, position, and intensity of the x-ray beam to the specific imaging scenario. The research leverages patient-specific anatomical models and mathematical models of imaging performance to direct x-rays where they are needed and, consequently, to avoid or to limit x-ray exposure where it is not needed. This will help maximize imaging performance for specific diagnostic tasks while minimizing radiation exposures.

Constructing tools for researchers
Cynthia McCollough, Mayo Clinic

The goal of this work is to develop resources that enable the research community to easily create and compare new approaches to reducing radiation dose of routine CT scans without compromising diagnostic accuracy. So far, this has entailed creating a library of raw data from patient CT scans that researchers can manipulate to test new approaches, and developing computer-based methods for evaluating new approaches, so that researchers don’t have to rely on radiologists, which can be costly and time consuming. Using these assets, researchers have demonstrated that there is considerable potential for radiation dose reduction in CT exams of the abdomen, which are among the highest dose CT exams in common clinical use.

Faster processing
Jeffrey Fessler, University of Michigan
To reduce radiation yet still produce good quality CT images, more sophisticated methods are needed to process the raw data from the CT system. Those advanced methods, called image reconstruction algorithms, can require undesirably long computing times, so they can be used only for some patients currently. The goal of this project is to develop algorithms that are fast enough to allow low-dose CT imaging to be used for every patient.>

An integrated approach
Norbert Pelc, Stanford Medical School
At every stage in the design of CT scanners, there are opportunities to make changes that reduce radiation dose. Because these changes are inter-related, the goal of this project is to take an integrated approach, exploring approaches such as modifying the photon counting detector (the part of the CT scanner that detects x-rays), dynamic x-ray illumination (adjusting the amount of radiation used throughout the duration of a scan), and image reconstruction methods. These will be tested using a table top experimental system. The researchers believe that these combined strategies can lead to as much as 80% reduction in radiation dose compared to today’s typical systems, and also enable higher resolution images.

Ricardo Otazo and Daniel Sodickson, New York University School of Medicine
Investigators at New York University School of Medicine, Brigham and Women’s Hospital, and Siemens Healthineers are working together to develop a new ultra-low-dose CT technique called SparseCT. The key idea behind SparseCT is to block most of the X-rays in a CT scan before they reach the patient, but to do so in a way that preserves all the essential image information. The approach combines a new x-ray blocking device with the mathematics of compressed sensing, which allows images to be reconstructed from reduced datasets. Compression sensing can be likened to filming a movie with a very fast, but low-pixel camera and then using math to convert the image to high-definition quality.

What are the Differences Between MRI and CT Scans?

News   //     //   What are the Differences Between MRI and CT Scans?

If you’ve been told you need MRI or CT scans, you may have a few questions. While traditional X-rays are still used for imaging in some cases, today’s technology allows for more detailed visuals of the inside of a patient’s body. Common imaging techniques include magnetic resonance imaging and computerized tomography. The differences between MRI and CT scans specifically are based on how the equipment functions, as well as what part of the body needs to be examined and why.

What is an MRI?

MRI stands for magnetic resonance imaging. It uses a magnetic field and radio waves to make detailed pictures of the inside of your body. These images are layered on top of each other to provide radiologists with a clearer understanding of the inside of your body.

MRIs are often used for images of:

  • Joints
  • Wrists
  • Ankles
  • Breasts
  • Blood vessels
  • Organs such as the heart, the brain, and kidneys

What is a CT Scan?

CT Scan, or CAT Scan, stands for computerized tomography. A CT scan takes a series of X-rays around your body and uses computer technology to create cross-sectional 2D images, or slices, of the area that is being imaged. When stacked together, these 2D images can create a 3D image, allowing for a much more detailed view than traditional X-rays can provide.

CT scans are often used to examine muscles, bones, and tumors, as well as to find internal bleeding.

CT scan equipment involves is a doughnut-shaped structure called a gantry that circles around the patient. The chamber of an MRI machine, on the other hand, is often enclosed.

Differences Between MRI and CT Scans

The biggest difference between MRI and CT scans is that MRIs use radio waves while CT scans use X-rays.

Following are several others.

  • MRIs are typically more expensive than CT scans.
  • CT scans may be quieter and more comfortable.
  • MRIs may take longer than CT scans. The length of time depends on the part of the body that is being imaged, but an MRI can take anywhere from 10 minutes to more than an hour. The average MRI time is about 40 minutes.
  • MRIs can show more detail than CT scans.
  • CT scans briefly expose patients to radiation. MRIs do not.
  • CT scan machines are open, which helps prevent anxiety among patients who are concerned about being in closed spaces. Instead, it uses a doughnut-shaped structure called a gantry that circles around the patient. On the other hand, the chamber of an MRI machine is often enclosed, and more of the body may be within an MRI chamber during imaging. Open MRI machines are available as well, which can be helpful for patients who are nervous about being in the enclosed chamber.

Similarities Between the Imaging Techniques

There are several similarities between both imaging processes. First, both have certain risks, such as the exposure to radiation during an MRI. In some cases, a contrast dye may be used with either MRI or CT, but some patients can have a negative reaction to the dye.  Additionally, both can be used to identify and monitor cancers, depending on where the cancer is located. Finally, patients who have a fear of enclosed spaces may have anxiety with either process, although various remedies can help calm patients.

For more information about the differences between MRI and CT scans, contact the Insight Imaging Center.

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90,000 Comparison of 10 modern automatic cat feeders

Top 10 Best Automatic Pet Feeders

! Promotion Automatic feeder for 6 feedings for cats and small breeds of dogs!

Do you not like getting out of bed very early in the morning to feed your beloved kitty? You are not alone. Do you also travel a lot? You will worry about how your cat will live in your absence.Do you work all day? All of these everyday problems can make caring for your pet difficult. However, it can be easily solved if you get one of the best automatic cat feeders.

Automatic feeders in the online store Wilbo.ru

What to consider before choosing an automatic feeder

Before choosing any automatic self-contained, non-volatile feed dispenser, you need to think about how it will keep your precious furry companion in the right shape.Studies have shown that in RUSSIA 50 percent of dogs and cats are overweight (this percentage is even higher among adult pets). When the feeders or containers used in feeding are not up to quality standards and the pets are fed in abundance, there is a high likelihood that the animal will become obese.

Cats tend to gain weight when they eat more calories than they can burn during their daily activities. Causes of overweight include:
Low activity (or inactivity)
Reproductive status
Diseases such as diabetes, hypothyroidism, and Cushing’s disease.
Breeding method.

Other things to consider :

Number of pets in your home
Before buying an automatic cat feeder, you need to consider the number of pets you have. It is recommended to buy separate automatic feeders for different pets. Some animals can be overly aggressive when eating, and you probably don’t want them to interfere with each other.It also becomes a problem that when eating from one bowl, animals will receive portions of different sizes.

Pets size and strength
Feeders are available in different sizes; you must be sure to buy the correct one. Some are made for large pets (allowing them to hold and distribute large food), while some are suitable for small animals.

If the animal is overweight, invest in a good food dispenser that has an automatic timer unit.This will allow your cat or dog to eat at the right time and just the right amount of food. With this type of feeder, you can feed your pets three times a day (morning, afternoon and evening). With this in mind, you can ensure that your cat stays well-fed and healthy.

Is it suitable for dogs or cats?
Some models of automatic feeders are specially designed for cats, while others are designed for dogs. The ones made for cats may actually work for small dogs, but you need to understand that the bodies of dogs and cats differ in dietary requirements and sizes.

Number of food products

The feeder automation unit should be able to dispense a minimum number of pieces at any given time, for example half a cup or thirty grams for each feeding time. In doing so, you can be sure that your pets will not overeat.

The feeder must also have a protected nozzle system. Cats and dogs can be so creative that they will do anything to get more bites ahead of time.And there are some who eat too fast. In this case, you need a feeder that will dispense pieces and granules into several parts for each feeding time. You can find a self-powered, battery-powered automatic cat feeder that automatically stops or closes if it notices that your pet is eating too fast.

Feeder efficiency and capacity
How much capacity can the feeder support? The large capacity feeder does not need to be replenished too often, only occasionally.He should be able to hold and distribute a suitable amount of food if you have multiple pets. An airtight bin is necessary if products will be stored inside the feeder for an extended period of time.
Automatic feeders in the online store Wilbo.ru
Attention should be paid to the shape and size of the feed pieces. Some feeders deliver feed through an intermediate container – a test tube. If the piece you are using is too large, it may get stuck in the feeder.Round food is not a problem, while square food can get stuck inside the tube.

# 1 Choice for hungry cats – Feed-Ex for dry food

As a pet owner looking for a programmable cat feeder, the Feed-Ex automatic pet feeder can be a great choice. This device allows pet owners to customize food portions for their pets and assign them correctly.If you prefer to limit your cat’s food intake, you can try the Feed-Ex device.

The automatic cat feeder control system is made possible by the portion control system. For example, 25 to 250 g at one meal four times a day. You can also record your voice and invite your favorite pet to feed.

What we liked

Made of durable materials, easy to set up.
Allows you to customize food portions.
Prevents fast food consumption with the possibility of slow feeding.
You can set up a voice call

Has a large feed tank

What we didn’t like
Programming functions are difficult for beginners

Buy Feede-ex on Wilbo.ru

# 2 Automatic Wet Cat Feeder – Feed and Go Automatic Feeder

Feed and Go block can be controlled from the Internet.It has a built-in microphone as well as a webcam that will allow you to track pets even when you are not there. Alternatively, you can also record your message to your cat so that they can receive it before eating. It connects to the internet using internal Wi-Fi. The feeder can handle 8 ounces of food and be scheduled for six meals a day.

What we liked

The device allows users to program the delivery time remotely.
Charts are subject to change using the Internet.
Quite robust housing
One feed option is started with one click.
Works on dry and wet food.
The user can program 6 meals with an interval of several minutes or hours.

What we didn’t like

It is not convenient for unskilled people.
This device requires an Internet connection.

# 3 Feed-ex with ice or water container

This low cost automatic feed dispenser for cats and small dogs is programmable for 4 feeds.The time at which the container should open is set. The water tank makes it possible to organize good nutrition for your pet.

What we liked
This pet feeder is relatively easy to use, with an easy to understand manual.
It is made of durable materials in a variety of colors to suit any interior. Battery powered, mobile to use, it is ideal for pet owners who want to control their pet’s food intake.
What we didn’t like
No full clock

This model has only 4 feedings

Buy the Feed-ex feeder on Wilbo.ru

# 4 Ideal Traveler Auto Feeder – SuperFeed CSF-3

The CSF-3 Feeder allows your cats to feed using the same bowl or different bowls. It has a Super Feeder option that dispenses food as well. This allows your pets to eat their meals in different compartments without interfering with each other.

This product also automates the feeding process in varying amounts, cutting from less than one cup to some cups of food daily. The timer allows you to program all the feed cycles.

What we liked

Relatively flexible.
Can customize delivery schedules.
Power interruptions do not require reprogramming.
Works best for small granules.
Sturdy gutter cover prevents cats from stealing their food.
Works for two cats with 8 feeding programs

What we didn’t like

Difficult to assemble.
Does not have a backup power supply.

# 5 LUSMO Automatic Food Dispenser for Weight Control

This feeder is attractive and portable. It is also easy to program so you can meet the special needs of your pet. With this device, users can program feeds up to three times a week.In addition, each meal can have separate portions.

Some of the notable features of this feeder are:

modern and colorful design,

assorted portions,

24/7 clock for LCD monitoring and more.

If you are a busy cat owner, this device is perfect for you.
Automatic pet feeder LUSMO

What we liked

The feeder allows pet owners to customize their food portions.
Meal times can be changed at different times.
Full stock can be maintained for up to 10 days
Lockable cover
Easy-to-read LCD monitor for time and battery status.

What we didn’t like

Not dishwasher safe.
The device does not work with every type of feed, especially with cubes and long ones.

# 6 Everything for cats in need of weight loss and diabetics – “Pet feeder”

PetSafe 5 Pet Feeder – automatic feeder for cats.This device can feed your pet at least 5 times a day, although only 4 meals can be programmed. This automatic soft food feeder can help prevent your pet from overeating. And with its digital timer, you can choose a good feeding schedule and set an extra one hour increase in the interval between each meal.


Made of durable polypropylene.
The product has five compartments with one dry container.
Has reliable protection against furry friends vandalism.
This device is relatively easy to program and also has a digital timer.
Removable food tray for easy cleaning, dishwasher safe.
The device requires four D-Cell batteries.
One year manufacturer’s warranty.

What we liked

Automatic dish dispenser and digital timer.
Has an accurate digital timer.
Easy to assemble and program.
Has an easily removable food tray.
Dishwasher safe.

What we didn’t like

Slightly noisy in use.
Batteries not included

# 7 Feeder for large cats or small dogs – PYRUS Large Automatic Cat Feeder

The design of the feeder is very similar to the Petmate feeder. However, it has several updates. It is manufactured with an LCD screen for easy operation. She also has a voice recording.She is programmable and can feed the cat three times a day.

What we liked

Large capacity.
It is also tough and heat resistant.
Convenient for outdoor use.
Records the voice of the owner.

What we didn’t like

Not suitable for wet feed or food.
Quite expensive.

# 8 New technologies for your pets Sititek Pets Pro Plus

This feeder is for advanced owners who keep up with the times and are not ready to part with their pet.The feeder has everything you need for a full life of the pet away from the owner.

Feed container capacity 4 liters


Built-in speaker


The feeder is controlled through a special application

What we liked
Ideal for owners who are rarely at home
You can see pets and talk to them
Easy to clean
What we didn’t like
Can be difficult to operate if you are not friendly with the technology

Buy SITITEK Pets Pro Plus on Wilbo.ru

# 9 Cheapest Automatic Cat Feeder – Petmate Feeder

This device has a transparent food container and this allows the pet owner to check the food level correctly.

This feeder has a simple design that looks beautiful in the kitchen. It is made of strong PET plastic and is a BPA free plastic that is safe and recyclable.

What we liked

Good quality.
It looks good for the price and it goes well with most kitchen designs.
Easy to clean and dishwasher safe.
Transparent and transparent bunker for checking the food level
Quite cheap relative to our comparative analysis of feeders.

What we didn’t like

Tray opening is too narrow.
The filling procedure is not very convenient.

# 10 Auto Feeder with Large Capacity – Bergan-11715-Travel-Feeder

This feeder is suitable for cat owners who are always on the go.It has a snap-on lid as well as a rotating bowl that closes when the cats finish their meal. The device closes easily and can keep fresh food in order.

It can be ideal for pet owners who travel a lot and small cats.

What we liked

Two in one device: for storing food, as well as for feeding pets.
Impressive feeding system.
Feeds pets for several weeks.
No refueling required as it automatically fills the bowl.
Food stays fresh thanks to the closing mechanism.

What we didn’t like

Not recommended for pets on a special diet
Due to its gravity, the power system continues to feed.

Cat Scanner – Cat Breed Identification on Android and iOS

Do you see a cat, but do not know its breed?

Just take a quick photo or video of your cat – with the Cat Scanner App you can reliably identify your cat breed in just seconds! Our built-in camera with Pinch To Zoom and Tap to Focus makes it easy to identify any breed of cat!

Of course, the Cat Scanner App also supports downloading images from your gallery.

Is there a mixed breed?

No problem, your app also recognizes mixed breeds! We provide you with details and interesting facts about the different breeds of your mixed breed cats.

All cat breeds in the Cat Scanner app!

The Cat Scanner app currently identifies about 60 different cat breeds. Our database includes all breeds officially recognized by the International Federation (FIFe) , and even some others!

By the way, our extensive database with information and photos of all breeds of cats (including unofficial ones) is also available completely without scanning!

Are there no cats nearby?

It doesn’t matter! Just scan yourself, your friends, family or those around you and find out which cats you look like the most!

It may sound a little odd, but it really works: the Cat Scanner app also recognizes people.Just take a quick selfishness and find out what kind of cat you are!

Become a part of our cat scanner community!

Share your results and compare with the community! Upload photos of your favorite cat to our Social Feed and share them with other cat lovers! View profiles and photos of other users, comment on posts from our feline community and filter by date or popularity!

Plus, you can easily share your messages with your friends by simply sending a photo directly from the Cat Scanner app.

Catch all breeds of cats and become an expert!

Catch all cat breeds just like in Pokémon Go. Scan at least one cat of each breed, complete the challenges, earn virtual treats and become a true feline expert!

Compete with your friends or community members and climb to the top of our ranking!

Give us feedback on the Cat Scanner app!

Let us know if the breed of the cat has been correctly identified.If not, you will receive helpful tips to improve your own results. If you also indicate what breed of cats is in the picture, you will help us improve our software, as the application will automatically know how to provide even more accurate results.

Suggest or vote for (unofficial) cat breeds you would like us to add to the app in the future!

Get Your Premium Upgrade!

In our premium version, the app will no longer display ads and your results will be available faster.What’s more, you can now choose whether to recognize your cat’s breeds quickly enough or more accurately. In the premium version, cat scanning is also possible offline, so you no longer need an active internet connection to identify their breeds. By purchasing our premium version as an option, you will also help support this application.

Find us on social networks!

On our social media channels, we bring you the most beautiful cat photos from the community.You will also find many interesting facts about your favorite pet. In addition, we will keep you updated on any new added features of the Cat Scanner app in the future.

* Instagram
* Facebook
* Twitter

Just try it!

Download the Cat Scanner app for free. Find it at Google Play for Android devices or Apple App Store for iPhone or iPad! Despite the small size of the application, you get all the possibilities and can determine the breed of the cat at any time or access our extensive database!

Have you ever seen a cat and wondered what kind of cat it is? Maybe you even know the breed, but can’t remember its name? Or do you have your own cat, the breed of which you still do not know? Well, maybe you know you have a mixed breed, but which breeds are actually part of your favorite?

Before you consider getting an expensive DNA test, the Cat Scanner App can help you answer all of these questions! Just scan your cat using the app and your cat’s breed will be automatically detected within seconds!


This app cannot transform your smartphone into a crazy spaceship capable of extracting your cat’s blood with a magic laser.The app makes educated predictions based on what it sees. On average, these predictions are reasonably accurate. However, it is obvious that the result can only be as good as the image / video you provide to the application. Moreover, it is impossible to correctly identify every cat. People tend to take it personally if their own pet cat is not predicted correctly. If you give the app a shot, you’ll see that its overall performance is pretty decent. Instead of paying a ton of money for a DNA test, you get this app for free.Enjoy!

90,000 Cat paw fracture – symptoms and treatment

If your cat drags its paw behind it, fearing to step on it, then most likely it has a fracture. What other signs might indicate bone damage? What to do if a fracture is found? Do I need to go to a veterinarian or can I do it myself at home? For more details, see below.

Read in this article:

Types of fractures in cats

Due to a fracture, the anatomical configuration of the bone changes: it is damaged and loses motor activity (in whole or in part).Veterinarians distinguish between acquired and congenital fractures. The latter account for no more than 5% of all requests.
Congenital injuries are diagnosed in kittens. They usually occur when pressure is applied to the abdominal cavity of a pregnant cat (for example, with careless handling of the pet, blows), as well as due to intrauterine abnormalities.
Acquired fractures have been observed in newborn kittens (eg, as a result of childbirth) as well as in adult cats.Usually they are caused by falling from a great height or being hit by heavy objects.

Classification of cat fractures:
Open . They pose the greatest danger, since the wound can be infected with pathogenic microorganisms.
Closed . They differ in that the bone is broken, but is located under the skin, so it is not visible.
Paws can break at one or several points at once (multiple fracture). The latter is usually found when a pet falls out of the window of a multi-storey building or a tall tree, especially when the animal hits branches, ropes and other obstacles when falling.


If we are talking about a congenital fracture, then its cause is a strong contraction of the uterus during childbirth or a quick (inaccurate) extraction of the fetus during a cesarean section. We strongly do not recommend giving birth to a cat on your own – contact a specialist to avoid undesirable consequences.
Common causes of fractures in adult pets:
• bruises,
• blows,
• pinched paws and subsequent improper release,
• road traffic injuries,
• falls,
• accidental household injuries.
In cats, pathologies of the musculoskeletal system can be diagnosed, in which spontaneous fractures are possible even with slight pressure on the bone that has already lost its anatomical strength.

Signs of a paw fracture

An obvious sign of a broken paw in a cat is its behavior. She avoids stepping on the injured foot. If the fracture is open, you will immediately see the damage and be able to take action. With a closed fracture, severe edema appears in its place.
Other signs that will help you identify a fracture:
• inability to straighten the leg to the end,
• sharp pain on palpation of the damaged area,
• unnatural bone mobility,
• change in the anatomical shape of the bone,
• movement on three legs.
Pay attention! If two or more paws are damaged, the animal will not be able to get up.

Your actions

What if my cat has a broken paw? If you think that the bone is damaged, provide the animal with complete rest: transfer it as carefully as possible to a comfortable bed (soft blanket) or to a carrier with a comfortable bottom.
If bleeding occurs, apply a tight tourniquet. However, do not squeeze the vessels strongly, otherwise necrosis (the process of tissue death) will begin, caused by a lack of nutrition. Apply a bandage, splint, or bandage.
Do not give your pet pain relievers or other medications (for example, antipyretics) on your own – this can worsen the cat’s condition. The best solution is to immediately take your pet to a veterinary clinic in Moscow!

Diagnosis of fracture

The initial stage of treatment is diagnostics.The veterinarian examines and gently probes the damaged area, then directs the pet for an x-ray examination. It allows you to make a diagnosis with 100% confidence, as well as to establish the nature of the fracture (chip, crack, break).
If necessary (for example, if you suspect other diseases), the specialist prescribes additional laboratory tests – general tests:
• blood,
• urine,
• feces.
Based on the results of the diagnosis, the veterinarian prescribes treatment.

Conservative therapy

Conservative treatment is prescribed for closed and uncomplicated fractures.The first stage is local anesthesia, the second is the extraction of bone fragments. The procedure concludes with the application of a plaster cast to eliminate the disturbance of the damaged area.
The veterinarian makes sure that the bandage fixes all nearby joints, but does not press on the limb or internal organs. In a veterinary clinic in Moscow, light polymer gypsum plates are used, applied for a period of 15 to 40 days.
Your doctor may prescribe corticosteroids to prevent inflammation.Pain relievers and sedatives are prescribed if necessary. They will help the animal’s body recover faster, and also contribute to the accelerated growth of bone tissue.
In addition, physiotherapy techniques can be used to ensure an accelerated recovery of the pet. On average, about 75-80% of cats recover with no surgical treatment and no surgery.

Surgical treatment

Complicated fractures (for example, splinter and depressed) require urgent help from a veterinarian-surgeon.He operates on the animal to connect the bone fragments and fix them securely. After the fusion of the bone tissue, all the material used for the connection (threads, pins) is removed.
Among the main methods of osteosynthesis:
Intramedullary . The bone fragments are connected using a reliable fixator-rod, which is inserted into the intramedullary canal. This technique is successfully applied in more than 35% of cases with fractures;
Extramedullary (lamellar) . Plates are applied to the damaged bone, and then fixed with screws.The main advantage of the method is strong fixation. It is usually used for comminuted as well as oblique fractures;
Extra-focal . External fixation is used using the needles: they are fixed above and below the fracture. Its advantage is minimal trauma and the possibility of physical activity, which reduces the likelihood of muscle atrophy.
The choice of surgical method depends on the condition of the pet and the nature of the paw fracture. Keep in mind that recovery from surgery takes 5 to 7 weeks.

Recovery period

After the operation, the pet is supervised in the hospital for 4-6 hours. This allows doctors to monitor his condition. Then suture treatment is prescribed, and painkillers are prescribed for a course of up to 7-10 days.
It is recommended to restrict your pet’s mobility for 4-6 weeks. If you walk your cat or let it go outside on your own, then leave it at home during the rehabilitation period. Place the animal in a large cage if possible.
3-4 weeks after the operation or the application of plaster, if conservative treatment is prescribed, it is necessary to go to the veterinary clinic again and take an X-ray. This will allow you to assess the speed and correctness of the bone fusion.
It is possible to quickly restore the motor function of the injured paw with regular manual massage. Ask your doctor for the technique. Massage improves blood circulation and prevents muscle atrophy.
The next important point is diet.We recommend transferring your pet to an easily digestible and balanced diet for the entire rehabilitation period. It is forbidden to prescribe multivitamin supplements on your own – consult a specialist and find out which vitamins and minerals will help your pet’s body recover faster.

See also:

90,000 They understand everything. How cats, dogs and other pets think

At school physics olympiads, tasks for “black boxes” are often given.Participants receive a box with unknown electrical components inside and several inputs and outputs. With the help of a voltmeter and an ammeter, students can take different measurements with this system, and then they must reconstruct which electrical circuit is inside the box.

There are a lot of similar “black boxes” in science, and the thinking of animals is perhaps one of the most mysterious among them. Such a task under the asterisk. We do not know for sure what is going on in the heads of our beloved animals, and we can only reason about their thoughts by the signals at the outputs of this system, that is, by their behavior in certain conditions.

Parrots: they know about the future and think in categories

American psychologist Irene Pepperberg had two unusual parrots. The first of them, Griffin, one might say, knew how to avoid momentary pleasures for the sake of long-term prospects. More precisely, he learned to give up oatmeal for the sake of more tempting treats – nuts and candy.

In the experiment, a cup of oatmeal was first placed in front of Griffin, and if after some time (from ten seconds to fifteen minutes) he did not touch this modest treat, then Griffin was rewarded with a delicious meal.Gradually, the parrot understood the rules of this simple game of patience and began to win the award in almost 90% of cases. And to cope with the temptation, he combed, yawned, or even threw the unfortunate cup of oatmeal to hell. In short, he behaved like a child in the famous experiment with marshmallows.

Another parrot Irene was named Alex, and he not only knew how to speak, but also distinguished objects by their shape, color, size and material. At the same time, the parrot did not mindlessly memorize objects along with their characteristics, but, apparently, collected in his head, albeit a small, but quite intelligible system of concepts.So, he correctly named the forms of geometric figures that he saw for the first time in his life (“four corners” or, say, “three corners”), or in response to the question “What color is the grain?” answered: “Yellow”, even when there were no grains around.

Alex also had logical categories like more-less or similar-same-different. In one experiment, he was shown two keys: one of them – metal – was smaller, and the other – made of green plastic – larger. The parrot was asked how they differ from each other, and Alex quite rightly answered that in color.Then he was asked an additional question about which of the keys is larger, and again received the correct answer – “green”.

However, even the most insensitive person could hardly call Alex such a feathered machine for categorizing objects. In experiments, he was often distracted from boring facts and could, for example, claim a banana as a reward or return to the cage with the words “I want to leave.” On September 5, 2007, when Irene was leaving the laboratory in the evening, Alex said: “You be good.See you tomorrow. I love you “(” Be good. See you tomorrow. I love you “), and these words were the last in the life of an unusual parrot. The next morning, Alex was found dead – he died from a sudden blockage of blood vessels.

Dogs: Look into a Black Box

Dogs are capable of a lot of different things and, for example, can distinguish up to 200 toys without any clues, but for cognitive scientists this is not the most important thing. Much more interesting is that the obedience of dogs and their devotion to man allows us to open the “black box” of animal thinking.

Today, dogs are the only animals that can willingly lie motionless in an MRI scanner if they are convinced that it is really necessary for their owners. With other animals, such tricks will not work: even if we manage to drive a cat or a rabbit into an MRI scanner, they are unlikely to lie there calmly and will allow us to remove the activity of their brain.

In one experiment, scientists studied what happens in a dog’s brain when it looks forward to pleasure. The animals were placed in an MRI scanner and a learned signal was given to them, which meant that soon the dog was expecting a reward in the form of a favorite treat.After that, the scientists turned on the tomograph and watched what was happening in the canine brain. It turned out that such delicious prospects triggered thought processes in animals, similar to human ones. The anticipation of a reward excited the caudate nucleus in the dog’s brain, just as this zone is “kindled” in businessmen by the anticipation of an imminent profit.

In this aspect, the thinking of dogs turned out to be quite similar to human, so it is not surprising that many dog ​​owners perceive their pets, if not as adults, then at least as shaggy and whining children.Experiments have shown that people who look their dogs in the eyes produce the neuromodulator oxytocin, which is also responsible for the formation of a mother’s feelings of attachment to her baby.

Cats: walk by themselves and have episodic memory

Where dogs are, there are cats, or rather the eternal comparison of dogs and cats, which is very difficult to correctly draw in cognitive ethology, which studies the thinking of animals. The fact is that cats are not such companionable creatures as dogs, and the authority of the owner for them is an almost elusive concept.At one time, the main mental resources of felines went not to social intelligence, as in those hunting in large, complex packs of wolves and dogs, but to the development of sensorimotor intelligence, without which it would be completely impossible for proud lone tigers or, say, leopards to catch fast prey.

Therefore, scientists plan their experiments on cats very carefully and try to involve them as much as possible in what is happening: they simply will not do anything on love for their owner alone.The easiest way to get cats interested is to offer them more food. This is what Japanese scientists did in a recent study.

In the first experiment, they took 49 cats and took turns running them into a room with four bowls full of food. The animals were allowed to taste a treat from two bowls, and then they were kicked out to be returned to the room a quarter of an hour later, where now there were four exactly the same, but completely empty bowls. The cats immediately began to look for the missing food, with particular zeal not exploring the bowls from which they had already eaten, but, on the contrary, the bowls untouched before: apparently, they naively assumed that the food in them definitely could not end and should just look and smell more closely to find the hidden treat.

In the second experiment, the cats were again offered four bowls, but now the layouts were changed: two bowls were filled with food, the third was empty, and the fourth contained a notoriously inedible object – a black hairpin. This time, the cats were allowed to eat from only one bowl, after which they were again kicked out to hell, and then returned to an empty table. In this case, the animals already paid the most attention to the only bowl where the normal, edible, and untested food they had never tried.

So in a neat experiment, scientists have shown that cats do not automatically follow the logic of “positive reinforcement – instinct” (there was delicious food, which means it may appear again), but on the contrary, they know how to compose completely whole ( although naive for observers) event models.

Pisces: complex social interactions

Temptations of parrots, the logic of a cat and such a human anticipation of pleasure in dogs – it might seem that if pets can think, then only the most “advanced” of them got such skill, and thoughts and feelings mysteriously arise only with the “spine”.But in reality, of course, this is not the case. The same fish still have something to surprise the skeptics with.

Take cleaner wrasses, for example. In nature, these small fish live on coral reefs and constantly serve other fish, removing parasites from their scales, gills and directly from their mouths. Swiss ethologist Reduan Bshari, in aquarium experiments supported by observations, studied how this underwater cleaning business is organized.

The fish swims to the working point of the wrasse and assumes some special posture.Someone spreads their fins wider and opens their mouths, someone freezes upside down in a column, but most importantly, the wrasse understands from this position that his client is ready for processing, and defines the newcomer in an impromptu queue, where unreliable nomadic fish are always taken forward, and only then, as far as possible, they move on to permanent sedentary fish, which can lazily sway with algae while waiting for reception, eat a little plankton, or do some other non-burdensome things like “read the magazines here for now”.

With each fish, the cleaners build their own strategy of relations. With someone they constantly and openly cheat, biting off particles of the skin of defenseless fish during a sanitary procedure, and for someone, on the contrary, a personal service plan: for example, wrasses do not accept sharks in their underwater office (sharks, by their nature, cannot stand on the spot), but serve right on the go, ingratiatingly circling around these formidable predators.

Thought everywhere

Ethologist Adriaan Cortland once observed how a wild chimpanzee interrupted an evening meal for 15 minutes to admire the colors of the sunset, and then, as if nothing had happened, returned to eating.In the text, we showed examples of conscious behavior only in domestic animals, not only because they are clearer and closer to people, but also because otherwise they would have drowned in the ocean of all kinds of examples.

Monkeys alone can do millions of different things – construct tools, plan their actions, learn from other people’s actions, and even sympathize with pain. In the London Zoo, they were even once taught to hold real tea parties, during which animals sat so decorously at the table that, under pressure from the wounded public, they had to be retrained to spill tea, break dishes and engage in other pranks that were incompatible with the real Victorian spirit.

Well, if even now you think that animals are simple soulless meat machines controlled by instincts, then here is the last story, far from both pets and smart monkeys. Once somewhere off the coast of California, divers helped a whale to get out of the nets of fishermen, and instead of retreating into the ocean in fear, he began to swim in a large circle around his rescuers and, cautiously approaching each person, as if to thank him with light pokes with his nose …The entire consciousness of this huge animal seemed to rejoice with one bright motive – “saved, I live.”

Many of the examples described in the text are taken from the book by Frans de Waal “Are we smart enough to judge the intelligence of animals”, published in Russian by the publishing house Alpina non-fiction.

Mikhail Petrov

How Cat Scanning Works – 2021

CAT Scanning takes the concept of traditional X-ray imaging to the next level.Instead of finding outlines of bones and organs, a CAT scan machine generates a complete 3D computer model of the patient’s interior. Doctors can even examine the body with one narrow slice of at a time to pinpoint specific areas.

In this article, we will go over the basic idea of ​​a CAT scan. While computer technology is quite advanced, the fundamental concept is actually very simple.


Computed Axial Tomography (CAT) scanners produce X-rays, a powerful form of electromagnetic energy . X-ray photons are the same as photons in visible light, but they have much more energy.This higher energy level allows X-rays to pass right through most of the soft material in the human body. (See How X-rays work to learn how X-rays do this, as well as how X-ray machines produce X-ray photons.)

A normal X-ray image is essentially a shadow: you shine a “light” on one side of your body, and a piece of film on the other side registers the silhouette of bones.

Shadows give you an incomplete idea of ​​the shape of an object.Imagine that you are standing in front of a wall, with your right hand pressing a pineapple to your chest, and with your left hand a banana. Your friend only looks at the wall, not at you. If you have a lamp in front of you, your friend will see the outline of you holding a banana, but not a pineapple – the shadow of your torso is blocking the pineapple. If the lamp is on your left, your friend will see the outline of a pineapple, but not a banana.

The same thing happens in a conventional X-ray image. If the larger bone is directly between the X-ray machine and the smaller bone, the larger bone may cover the smaller bone on the film.To see the smaller bone, you need to rotate your body or move the X-ray machine.

To know that you are holding a pineapple and a banana, your friend will need to see your shadow in both positions and form a complete mental image. This is the basic idea behind computed tomography. In a CAT scanner, an X-ray beam moves around the patient, scanning from different directions. The computer takes all this information and collects 3D images of bodies.

Scan Procedure

Scanned Liver Piece

The CAT machine looks like a giant donut tipped over on its side.The patient lies down on a platform that moves slowly through the opening in the machine. The X-ray tube is mounted on a movable ring along the edges of the hole. The ring also supports an array of X-ray detectors directly opposite the X-ray tube.

This content is not compatible with this device.

The motor turns the ring so that the X-ray tube and X-ray detectors rotate around the body. Each complete revolution scans a narrow, horizontal slice of a “body.The control system moves the platform further into the hole so the tube and detectors can scan the next slice.

Thus, the apparatus records X-ray slices throughout the body in spiral movement. The computer changes the intensity of the X-rays to scan each tissue at the optimum power. After the patient passes through the machine, the computer combines all the information from each scan to form a detailed image of the body.Of course, there is usually no need to scan the entire body. More often than not, doctors will only scan a small section.

Since they examine the body in parts, from all sides, the CAT scan of the is much more complete than conventional radiography. Today, doctors use computed tomography to diagnose and treat a wide range of conditions, including head trauma, cancer, and osteoporosis. They are an invaluable tool in modern medicine.

For more information on CAT scan machines and other medical scanners, follow the links on the next page.

90,000 Cost of animal chipping in St. Petersburg

First of all, this procedure is necessary for the identification of the animal. The stigma fades over time, it can be interrupted for another, and if the pet is lost and another person found it, then he may simply not notice it, for example, if it is in the abdomen. The chip is an electronic analogue of a passport for cats and dogs, it is unique.

Also, an unchipped pet cannot visit the countries of the European Union.If you are going on a joint vacation with your pet or want to take part in an exhibition abroad, it is worth taking your four-footed friend for this procedure. It is completely safe and painless, healthy animals can be chipped in the first month of life.


  • A technician checks the functionality of the chip using a scanner.
  • Using a special syringe, the product is injected under the skin together with a special solution.
  • The doctor checks the chip again with the scanner to make sure the procedure was successful.
  • All animal data are entered into a single database. It is assigned a unique fifteen-digit code (in most cases). Information about the pet and its owner is attached to this code. Thanks to this, in the future, the identification process will take only a few seconds.

After that, within three days, it is necessary to monitor the behavior of the animal and stop all attempts to comb the place where the injection was made.

What is needed for chipping?

  • Veterinary passport of the animal of international standard. If you do not have such a document, you can issue it in our clinic.
  • Owner’s passport.


In the summer and spring, when it gets warm, and the owners begin to open windows, balconies and air vents, there is an influx of messages about missing cats.Some tailed fidgets run away out of curiosity, others are driven by ancient instinct. An animal that has been chipped is much easier to find, and its chances of being returned to the family grow severalfold.

If your animal has breeding value, and you decide to mate in one of the EU countries, you will have to microchip your pet.


Certain breeds have a tendency to escapes, some individuals are shy and during a promenade without a leash in case of danger (sharp clap, car signal, thunder, the appearance of a cyclist or an aggressive relative) can rush off in an unknown direction.Chipping makes it easier to find and prevents scammers from taking advantage of your trouble. The cost of the procedure is low, so every owner can afford to carry it out.

Owners of purebred dogs often participate in exhibitions, including foreign ones. To enter the European Union, a pet must have a chip.

In the veterinary clinic “Dog and Cat” you can use the service of chipping animals at affordable prices in St. Petersburg. The cost for veterans, disabled people and pensioners has been reduced, there are permanent discounts.

You can find out how much this service costs on the website, as well as from the administrators of the IEC “Dog and Cat” by phone (812) 407-17-19 or (812) 603-49-32.

Features of the chipping procedure

  1. Impossibility of chip counterfeiting. The chip is designed in such a way that the information on it (identification number) cannot be damaged or falsified. The brand can fade it can be interrupted, the microchip will remain unique.
  2. E-Passport – the key to your peace of mind.Each dog or cat that has received an individual chip is entered into a single electronic database.
  3. The effectiveness of the search for missing animals. According to the website animal-id.ru: “A study of more than 7,700 stray animals in animal shelters showed that 21.9% of dogs without microchips were returned to owners, while 52.2% of chipped dogs were returned to owners. Chipped cats were only 1.8% reunited with their owners, while chipped cats returned home at 38.5% of cases. ”
  4. Simplicity and safety of the procedure. By the nature of the procedure, the introduction of a microchip can be correlated with a subcutaneous injection. The microchip itself does not cause discomfort to the pet.

What is needed for chipping?

  • Veterinary passport of the animal of international standard. If you do not have such a document, you can issue it in our clinic.
  • Pet owner’s passport.

After that, within three days, it is necessary to monitor the behavior of the animal and stop all attempts to comb the place where the injection was made.

Database, scanner, microchip

The unique number of the animal is entered into a unified Animal ID database. The data of the veterinary passport and the contact details of the owner are also stored there.

A scanner is a device with which you can “read” the microchip number. The doctor must use the scanner to check the information on this device, both before implantation and after the introduction of the chip to the animal.

The microchip itself is a microcircuit with a unique number in the capsule.The dimensions of the microchip are insignificant, and the capsule is made of biocompatible material, which excludes the possibility of rejection.

SQL as tools for linux – scanning files and working with CAT and ECHO commands

I found some interesting tools like q, they give flexibility in using SQL over files.

I’m looking for some tools like this, but they might even work with cat and echo commands.


file.txt would be like this.

  id name
1 aaa
2 bbb

The tool can work as follows

  cat file.txt | sqltool select * from output

And yet I cannot find anything like it. If anyone knows please suggest.







June 22, 2020 at 00:24

1 answer

  • size with multiple teams

    In the current directory, I would like to print the name of the file and its contents.#> countryInfo-n.txt After some research, I found that cat is for concatenation and grep is for regular searching for exp (don’t know if I’m right), but why …


In the Structured Text Tools repository
github has a good list of SQL command line tools.



June 22, 2020 at 03:19 AM

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