What is a CT scan and how does it work. How does contrast enhance CT imaging. What are the various applications of CT scans in modern medicine. How should patients prepare for a CT scan. What precautions should be taken before undergoing a CT scan. How does CT technology compare to other imaging methods. What advancements are shaping the future of CT scanning

The Fundamentals of CT Scanning: Unveiling the Inner Workings

Computed Tomography (CT) scanning is a revolutionary imaging technique that has transformed diagnostic medicine. But what exactly is a CT scan? A CT scan, also known as computed tomography, is a sophisticated diagnostic imaging procedure that combines X-ray technology with advanced computer processing to create detailed cross-sectional images of the body’s internal structures.

How does a CT scan differ from traditional X-rays? Unlike standard X-rays, which produce a single two-dimensional image, CT scans capture multiple images from various angles as the X-ray beam rotates around the patient. This circular motion allows for a comprehensive view of organs, bones, blood vessels, and other tissues, providing significantly more detail than conventional X-rays.

The CT Scanning Process: A Step-by-Step Breakdown

1. Patient positioning on the CT table
2. X-ray tube rotation around the body
3. Multiple X-ray beams pass through the body at different angles
4. Detectors capture the X-rays after they pass through the body
5. Computer processing of the collected data
6. Generation of cross-sectional images or “slices”
7. Creation of 3D reconstructions when necessary

What makes CT scans so valuable in modern medicine? The ability to visualize internal structures in great detail allows healthcare professionals to diagnose a wide range of conditions, plan treatments, and monitor the effectiveness of interventions with unprecedented accuracy.

Enhancing Clarity: The Role of Contrast in CT Imaging

Contrast media play a crucial role in many CT examinations, but what exactly is contrast, and why is it used? Contrast agents are substances that temporarily alter how X-rays interact with the body, enhancing the visibility of specific structures or abnormalities in CT images.

There are two primary types of contrast used in CT scanning:

• Oral contrast: Typically a barium-based solution that patients drink before the scan
• Intravenous (IV) contrast: An iodine-based solution injected into a vein

How does contrast improve CT imaging results? Contrast agents can highlight blood vessels, organs, and other structures, making it easier for radiologists to identify abnormalities such as tumors, infections, or vascular issues. This enhanced visibility often leads to more accurate diagnoses and better treatment planning.

The Double-Contrast Study: Maximizing Diagnostic Potential

What is a double-contrast CT study? This technique involves the use of both oral and IV contrast to provide comprehensive imaging of the gastrointestinal tract and surrounding structures. The oral contrast outlines the digestive system, while the IV contrast enhances blood vessels and organ perfusion, offering a complete picture of abdominal and pelvic anatomy.

CT Scans in Action: Diverse Applications in Modern Medicine

The versatility of CT scanning technology has led to its widespread adoption across various medical specialties. What are some of the key applications of CT scans in contemporary healthcare?

• Diagnosis of tumors and cancers
• Detection of internal injuries and bleeding
• Evaluation of bone and joint problems
• Assessment of lung diseases and cardiac conditions
• Guidance for biopsies and minimally invasive procedures
• Planning for radiation therapy and surgical interventions
• Monitoring of treatment effectiveness

How do CT scans contribute to emergency medicine? In trauma cases, CT scans can rapidly identify life-threatening injuries, allowing for prompt and appropriate treatment. The speed and detail provided by CT imaging make it an invaluable tool in emergency departments worldwide.

CT-Guided Procedures: Precision in Intervention

Beyond diagnostic imaging, how are CT scans used in medical procedures? CT guidance enables physicians to perform minimally invasive interventions with remarkable accuracy. These procedures may include:

• Needle biopsies of suspicious masses
• Drainage of abscesses or fluid collections
• Precise placement of radiation therapy
• Guidance for orthopedic procedures

By providing real-time imaging during these interventions, CT technology helps minimize complications and improve patient outcomes.

Patient Preparation: Ensuring Optimal CT Scan Results

Proper preparation is crucial for obtaining high-quality CT images and ensuring patient safety. How should patients prepare for a CT scan? The specific instructions may vary depending on the type of scan and whether contrast is required, but general guidelines often include:

• Fasting for a specified period before the exam (if contrast is used)
• Removing metal objects, including jewelry and certain clothing items
• Informing the healthcare team about any allergies or medical conditions
• Discussing current medications with the doctor, especially for patients with diabetes

What should patients expect during the CT scan procedure? The actual scanning process is typically quick and painless, often taking only a few minutes. Patients lie on a table that moves through the CT scanner, which resembles a large doughnut-shaped machine. The technologist may provide breathing instructions to ensure clear images.

Special Considerations for Contrast Studies

How does preparation differ for CT scans with contrast? When contrast is required, additional steps may include:

• Drinking oral contrast solution before the exam
• Having an IV line placed for administration of intravenous contrast
• Extended fasting periods to ensure optimal contrast distribution
• Specific instructions for diabetic patients regarding medication management

What precautions should be taken regarding contrast allergies? Patients with a history of allergic reactions to contrast media should inform their healthcare provider well in advance. In some cases, premedication with antihistamines or corticosteroids may be recommended to reduce the risk of adverse reactions.

Safety First: Precautions and Considerations in CT Scanning

While CT scans are generally safe and non-invasive, there are important precautions to consider. What are the key safety considerations for CT scans?

• Radiation exposure: CT scans use ionizing radiation, which can pose risks with repeated exposure
• Pregnancy: CT scans are typically avoided during pregnancy unless absolutely necessary
• Contrast reactions: Although rare, some patients may experience allergic reactions to contrast media
• Kidney function: Patients with kidney problems may be at higher risk for complications from iodine-based contrast

How do healthcare providers balance the benefits and risks of CT scanning? The decision to perform a CT scan is always based on a careful consideration of the potential diagnostic benefits versus the risks associated with radiation exposure and contrast use. In many cases, the valuable information obtained from a CT scan far outweighs the minimal risks involved.

Radiation Dose Optimization: Striking the Right Balance

What strategies are employed to minimize radiation exposure during CT scans? Modern CT scanners incorporate various dose reduction techniques, including:

• Automatic exposure control
• Iterative reconstruction algorithms
• Protocol optimization based on patient size and scan purpose
• Use of shielding for radiosensitive organs when appropriate

These advancements allow for high-quality imaging with the lowest possible radiation dose, adhering to the ALARA principle (As Low As Reasonably Achievable).

CT Technology: Advancements and Future Directions

The field of CT imaging continues to evolve rapidly, with new technologies enhancing image quality, reducing radiation dose, and expanding clinical applications. What are some of the recent advancements in CT technology?

• Dual-energy CT: Allowing for better tissue characterization and material differentiation
• Spectral CT: Providing additional information about tissue composition
• Ultra-high resolution CT: Offering unprecedented detail for specific applications
• Artificial intelligence integration: Enhancing image reconstruction and analysis

How are these advancements shaping the future of medical imaging? These innovations are not only improving diagnostic accuracy but also opening up new possibilities for personalized medicine, treatment planning, and disease monitoring.

CT in the Era of Artificial Intelligence

What role does artificial intelligence (AI) play in modern CT imaging? AI algorithms are increasingly being integrated into CT workflows to:

• Automate image analysis and detection of abnormalities
• Improve image quality while reducing radiation dose
• Enhance workflow efficiency in radiology departments
• Assist in quantitative imaging and radiomic analysis

The combination of advanced CT hardware and AI-powered software is paving the way for more precise, efficient, and personalized diagnostic imaging.

CT Scanning vs. Other Imaging Modalities: Choosing the Right Tool

While CT scanning is a powerful diagnostic tool, it’s essential to understand its strengths and limitations compared to other imaging modalities. How does CT compare to other common imaging techniques?

CT vs. MRI

What are the key differences between CT and MRI? CT scans excel at imaging bone, lung tissue, and acute bleeding, while MRI provides superior soft tissue contrast and does not use ionizing radiation. CT is generally faster and more widely available, making it the preferred choice for emergency situations.

CT vs. Ultrasound

How does CT compare to ultrasound imaging? Ultrasound offers real-time imaging without radiation exposure and is particularly useful for examining soft tissues and blood flow. However, CT provides more comprehensive imaging of deep structures and is less operator-dependent.

CT vs. PET

What distinguishes CT from PET scanning? While CT provides detailed anatomical information, PET scans offer insights into metabolic activity and cellular function. PET/CT hybrid systems combine the strengths of both modalities for comprehensive imaging, particularly in oncology.

The choice of imaging modality depends on various factors, including the clinical question, patient characteristics, and urgency of the situation. Radiologists and referring physicians work together to determine the most appropriate imaging technique for each patient’s specific needs.

The Patient Experience: Navigating the CT Scanning Process

Understanding what to expect during a CT scan can help alleviate patient anxiety and ensure a smooth experience. What does the typical CT scanning process entail for patients?

1. Check-in and registration
2. Review of medical history and any contraindications
3. Changing into a hospital gown if necessary
4. Placement of an IV line for contrast studies
5. Positioning on the CT table
6. Brief scanning period (usually 5-30 minutes)
7. Post-scan monitoring for contrast reactions (if applicable)
8. Return to normal activities (unless otherwise instructed)

How can patients prepare mentally for a CT scan? Being informed about the procedure, communicating any concerns with the healthcare team, and practicing relaxation techniques can help reduce anxiety and ensure a positive experience.

Addressing Common Patient Concerns

What are some frequently asked questions about CT scans, and how can they be addressed?

• Is the procedure painful? CT scans are generally painless, though IV contrast injection may cause brief discomfort.
• How long does it take? Most CT scans are completed within 30 minutes, with actual scanning time often less than 5 minutes.
• Will I be claustrophobic? Unlike MRI, CT scanners have a wide, open design that rarely causes claustrophobia.
• What about radiation risks? The benefits of diagnostic information usually outweigh the minimal risks of radiation exposure from a single CT scan.

By addressing these concerns proactively, healthcare providers can help ensure patients feel comfortable and informed throughout the CT scanning process.

Interpreting CT Results: From Images to Insights

The acquisition of CT images is just the first step in the diagnostic process. How are CT scan results interpreted and communicated to patients?

1. Image review by radiologists
2. Analysis of anatomical structures and potential abnormalities
3. Correlation with clinical information and other imaging studies
4. Generation of a detailed radiology report
5. Communication of findings to the referring physician
6. Discussion of results and treatment options with the patient

What role do radiologists play in CT interpretation? Radiologists are specially trained physicians who analyze CT images, identify abnormalities, and provide expert interpretations to guide clinical decision-making.

Beyond Visual Interpretation: Quantitative CT Analysis

How is advanced technology enhancing CT image interpretation? Modern CT analysis goes beyond visual inspection to include:

• Volumetric measurements of organs and tumors
• Density analysis for tissue characterization
• Perfusion studies to assess blood flow
• Texture analysis for subtle pattern recognition
• AI-assisted detection and classification of abnormalities

These quantitative techniques provide objective data to complement the radiologist’s expertise, leading to more precise diagnoses and treatment planning.

The Economic Impact of CT Scanning in Healthcare

While CT scanning has revolutionized diagnostic medicine, it’s important to consider its economic implications. How does the widespread use of CT technology affect healthcare costs and resource allocation?

• Initial investment in CT equipment and facilities
• Ongoing costs for maintenance, upgrades, and staff training
• Potential for cost savings through early diagnosis and treatment
• Impact on healthcare insurance premiums and coverage
• Considerations for appropriate use to avoid unnecessary scans

How do healthcare systems balance the costs and benefits of CT scanning? Many institutions implement evidence-based guidelines and decision support tools to ensure appropriate utilization of CT scans, maximizing their diagnostic value while minimizing unnecessary expenses.

CT Scanning in Global Health Contexts

What role does CT scanning play in global health efforts? While CT technology is widely available in developed countries, access remains limited in many low- and middle-income regions. Efforts to expand CT availability globally include:

• Development of more affordable CT systems
• Implementation of mobile CT units for remote areas
• Training programs for radiologists and technologists in developing countries
• Telemedicine initiatives for remote image interpretation

These efforts aim to reduce global health disparities by improving access to advanced diagnostic imaging in underserved populations.

Computed Tomography (CT) Scan | Johns Hopkins Medicine

What You Need to Know

• A CT scan is a diagnostic imaging exam that uses X-ray technology to produce images of the inside of the body.
• A CT scan can show detailed images of any part of the body, including the bones, muscles, organs and blood vessels.
• CT scans can also be used for fluid or tissue biopsies, or as part of preparation for surgery or treatment.
• CT scans are frequently done with and without contrast agent to improve the radiologist’s ability to find any abnormalities.

What is a CT scan?

Computed tomography is commonly referred to as a CT scan. A CT scan is a diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce images of the inside of the body. It shows detailed images of any part of the body, including the bones, muscles, fat, organs and blood vessels.

CT scans are more detailed than standard X-rays. In standard X-rays, a beam of energy is aimed at the body part being studied. A plate behind the body part captures the variations of the energy beam after it passes through skin, bone, muscle and other tissue. While much information can be obtained from a regular X-ray, a lot of detail about internal organs and other structures is not available.

In CT, the X-ray beam moves in a circle around the body. This allows many different views of the same organ or structure and provides much greater detail. The X-ray information is sent to a computer that interprets the X-ray data and displays it in two-dimensional form on a monitor. Newer technology and computer software makes three-dimensional images possible.

CT scans may be performed to help diagnose tumors, investigate internal bleeding, or check for other internal injuries or damage. CT can also be used for a tissue or fluid biopsy.

Why are CT scans sometimes ordered with contrast?

CT scans may be done with or without contrast. Contrast refers to a substance taken by mouth or injected into an IV line that causes the particular organ or tissue under study to be seen more clearly. Contrast examinations may require you to fast for a certain period of time before the procedure. Your doctor will notify you of this prior to the procedure.

You will need to let your doctor know if you have ever had a reaction to any contrast media and/or any kidney problems. A reported seafood allergy is not considered to be a contraindication for iodinated contrast. If you have any medical conditions or recent illnesses, inform your doctor.

How do I prepare for a CT scan?

If you are having a computed tomography angiography (CTA) or a virtual colonoscopy, you will be given specific instructions when you make your appointment.

PRECAUTIONS: If you are pregnant or think you may be pregnant, please check with your doctor before scheduling the exam.

CLOTHING: You may be asked to change into a patient gown. If so, a gown will be provided for you. Please remove all piercings and leave all jewelry and valuables at home.

CONTRAST MEDIA: Contrast may be indicated for your exam. The contrast media improves the radiologist’s ability to find structures that are abnormal and understand normal anatomy better.

• Some patients should not have an iodine-based contrast media. If you have problems with your kidney function, please inform your radiologist in advance. We may be able to perform the scan without the contrast media or find an alternate imaging exam.
• The most common type of CT scan with contrast is the double-contrast study, which will require you to drink a contrast media before your exam begins in addition to the IV contrast. The more contrast you are able to drink, the better the images are for the radiologist to visualize your digestive tract.

ALLERGY: Please inform the access center representative when you schedule your scan if you have had an allergic reaction to any contrast media. IV contrast will not be administered if you have had a severe or anaphylactic reaction to any contrast media in the past. Mild to moderate reactions warrant a plan that includes taking medication prior to the CT examination. These plans will be discussed with you in detail when you schedule your exam. Any known reactions to a contrast media should be discussed with your personal physician.

EAT/DRINK: If your study was ordered without contrast, you can eat, drink and take your prescribed medications prior to your exam.

If your doctor orders a CT scan with contrast, do not eat anything three hours prior to your CT scan. We encourage you to drink clear liquids. You may also take your prescribed medications prior to your exam.

DIABETICS: People with diabetes should eat a light breakfast or lunch three hours prior to the scan time. Depending on your oral medication for diabetes, you may be asked to discontinue use of the medication for 48 hours after the CT examination. Detailed instructions will be given following your examination.

MEDICATION: All patients can take their prescribed medications as usual.

The Newest CT: Faster Than a Heartbeat

A new CT scanner will change the management and outcomes of coronary artery disease. The CT scan captures images of the heart between beats, leading to clearer images to help detect anatomic and functional characteristics of coronary artery disease. This technology can also be used to help replace invasive tests to determine which patients with chest pain need intervention.

Read more

What are the risks of a CT scan?

If you are pregnant or think you may be pregnant, you should notify your health care provider.

The amount of radiation dose used in a CT scan is small. You may want to ask your doctor about the amount of radiation used during the CT procedure and the risks related to your particular situation.

If you are claustrophobic or tend to become anxious easily, tell your doctor ahead of time. You may be prescribed a mild sedative to take before the procedure to make you more comfortable.

What happens during a CT scan?

CT scans may be performed on an outpatient basis or as part of your stay in a hospital. Procedures may vary depending on your condition and your physician’s practices. Generally, CT scans follow this process:

• You may be asked to change into a patient gown. If so, a gown will be provided for you. A locker will be provided to secure all personal belongings. Please remove all piercings and leave all jewelry and valuables at home.
• If you are to have a procedure done with contrast, an IV line will be started in the hand or arm for injection of the contrast media. For oral contrast, you will be given a liquid contrast preparation to swallow. In some situations, the contrast may be given rectally.
• You will lie on a scan table that slides into a large, circular opening of the scanning machine.
• The technologist will be in another room where the scanner controls are located. However, you will be in constant sight of the technologist through a window. Speakers inside the scanner will enable the technologist to communicate with and hear you. You may have a call button so that you can let the technologist know if you have any problems during the procedure. The technologist will be watching you at all times and will be in constant communication.
• As the scanner begins to rotate around you, X-rays will pass through the body for short amounts of time. You will hear clicking sounds, which are normal.
• The X-rays absorbed by the body’s tissues will be detected by the scanner and transmitted to the computer. The computer will transform the information into an image to be interpreted by the radiologist.
• It is important that you remain very still during the procedure. You may be asked to hold your breath at various times during the procedure.
• If contrast media is used for your procedure, you may feel some effects when the contrast is injected into the IV line. These effects include a flushing sensation, a salty or metallic taste in the mouth, a brief headache, or nausea and/or vomiting. These effects usually last for a few moments.
• You should notify the technologist if you have any breathing difficulties, sweating, numbness or heart palpitations.
• When the procedure has been completed, you will be removed from the scanner.
• If an IV line was inserted for contrast administration, the line will be removed.
• While the CT procedure itself causes no pain, having to lie still for the length of the procedure might cause some discomfort or pain, particularly in the case of a recent injury or invasive procedure, such as surgery. The technologist will use all possible comfort measures and complete the procedure as quickly as possible to minimize any discomfort or pain.

What happens after a CT scan?

• If contrast media was used during your procedure, you may be monitored for a period of time for any side effects or reactions to the contrast, such as itching, swelling, rash or difficulty breathing.
• If you notice any pain, redness and/or swelling at the IV site after you return home following your procedure, you should notify your doctor, as this could indicate an infection or other type of reaction.
• There is typically no special type of care required after a CT scan. You may resume your usual diet and activities unless your doctor advises you differently.
• Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation.

What are some of the advances in CT technology?

Advances in CT technology include:

• High-resolution CT: This type of CT scan uses very thin slices (less than 0. 1 inches), which are effective in providing greater detail in certain conditions, such as lung disease.
• Helical or spiral CT: During this type of CT scan, both the patient and the X-ray beam move continuously, with the X-ray beam circling the patient. The images are obtained much more quickly than with standard CT scans. The resulting images have greater resolution and contrast, providing more detailed information. Multidetector-row helical CT scanners may be used to obtain information about calcium buildup inside the coronary arteries of the heart.
• Ultrafast CT (also called electron beam CT): This type of CT scan produces images very rapidly, thus creating a type of “movie” of moving parts of the body, such as the chambers and valves of the heart. This scan may also be used to obtain information about calcium buildup inside the coronary arteries of the heart, but the helical scanners are much more common.
• Computed tomographic angiography (CTA): Angiography (or arteriography) is an X-ray image of the blood vessels. A CT angiogram uses CT technology rather than standard X-rays or fluoroscopy to obtain images of blood vessels — for example, the coronary arteries of the heart.
• Combined positron emission tomography and CT (PET/CT): The combination of CT and positron emission tomography technologies into a single machine is referred to as PET/CT. PET/CT combines the ability of CT to provide detailed anatomy with that of PET to show cell function and metabolism in order to offer greater accuracy in the diagnosis and treatment of certain types of diseases, particularly cancer. PET/CT may also be used to evaluate conditions such as epilepsy, Alzheimer’s disease and coronary artery disease.

CT Scan – Uses, Procedure & Risks

By Joseph Bennington-CastroMedically Reviewed by Rosalyn Carson-DeWitt, MD

Reviewed: October 19, 2015

Medically Reviewed

CT scans, or ‘CAT scans,” produce highly detailed X-ray images of your body to reveal numerous health issues.

Computed tomography (CT) is a diagnostic procedure that’s sometimes referred to as computed axial tomography, or a “CAT scan.”

CT scans use X-rays to produce 2D cross-sectional images, or slices, of the body’s bones, soft tissues, and blood vessels.

Using computers, these images can be “stacked” to create 3D models of specific areas of the body.

Unlike traditional X-ray imaging technologies, which use a fixed X-ray source, CT scanners use a motorized X-ray source that rotates around the body, allowing for more detailed images.

CT Scan Uses

Physicians may order CT scans to:

• Examine internal and bone injuries from vehicle accidents or other trauma
• Diagnose spinal problems and skeletal injuries
• Detect osteoporosis
• Detect many different types of cancers and determine the extent (spread) of the tumors
• Locate infections
• Look for injuries, stroke-causing clots, hemorrhaging, and other issues in the head
• Image the lungs to reveal blood clots in the lungs’ vessels, excess fluid, pneumonia, and chronic pulmonary obstructive disease (COPD)
• Determine the cause of chest or abdominal pain, difficulty breathing, and other symptoms
• Diagnose dangerous vascular diseases that can cause stroke, kidney failure, and death

Additionally, CT scans are used to assist with biopsies and other medical procedures, and help with treatment planning for organ transplants, gastric bypass, and cancer, among other things.

CT Scan Procedure

The procedure begins with you lying on a narrow table that slides in and out of the center of the CT scanner.

The X-ray source and X-ray detectors are located on opposite sides of the scanner’s ring, or gantry.

During the scan, the gantry will rotate around you, sometimes while you move through the scanner’s tunnel.

The source sends X-rays through your body, which the detectors pick up and a computer translates into images.

To image soft tissues, your physician may use a special dye (called a contrast dye) during the test to help visualize these body parts, which may otherwise be difficult to see.

The contrast may be ingested, given via IV, or administered rectally with an enema.

CT Scan Risks

Some people are allergic to the ingredients in the contrast dye, resulting in nausea and vomiting, sneezing, itching, or hives.

Anaphylaxis, a life-threatening allergic reaction, or kidney failure may also occur.

Also, CT scans produce far more ionizing radiation than traditional X-rays.

A single abdominal scan, for example, delivers up to 400 times the radiation of a single chest X-ray, according to the National Institute of Biomedical Imaging and Bioengineering.

Rare complications of this radiation include:

• Increased lifetime risk of cancer
• Skin reddening and tissue injury
• Hair loss
• Cataracts
• Birth defects if used during pregnancy

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How CT works

We will tell you about the method itself, answer questions about how CT is done, how the procedure goes, and what advantages it has. If you have additional questions, you can find the information you are interested in on the site, ask a question in the chat or call our call center.
We are happy to answer your questions!

What is computed tomography?

Computed tomography (CT) is a medical X-ray examination that allows you to get a layered image of the internal organs. X-rays pass through the human body, and a computer forms an image of thin sections.

The image shows images of the lungs taken during a CT scan. 1 – longitudinal (frontal) section, 2 – transverse (axial) section.
Diagram 3 shows the path of the rays.

X-ray

X-rays are a natural type of radiation. In everyday life, we are regularly exposed to x-rays. The absorbed energy of ionizing radiation is measured in milliSieverts (mSv). According to statistics, a person receives an exposure equal to 3 mSv per year. X-ray radiation is a carcinogen, that is, in the process of accumulation in the human body, it can cause the appearance of malignant tumors, therefore, studies must be carried out according to indications, strictly in the direction of a doctor.

How CT is done

The X-ray generator emits rays that, passing through the human body, lose some of their energy and are captured by a special detector. The denser the organ through which the radiation passes, the more energy is lost. Based on the difference between the initial beam energy and the output beam energy, a computer system generates an image, which is then examined by a radiologist.

The computer tomograph forms a series of images by “layered” shooting. The X-ray beam passes through a thin layer of the human body, which during scanning gradually moves perpendicular to the axis of rotation of the X-ray tube; at the exit from the human body, the attenuated X-ray radiation is detected by the detector. Thus, after computer processing of the array of received data, a lot of thin sections of the studied part of the body are obtained in one scan.

Depending on the purpose of the examination, the doctor independently regulates the thickness and interval of the cut (step).

The technology that allows you to create an almost continuous image using an additional spiral beam is called multislice computed tomography (MSCT).

Purpose CT

Computed tomography is used to obtain images of:

• bones;
• soft tissues;
• blood vessels;
• chest;
• brain;
• abdominal organs;
• pelvic organs.

Often, computed tomography is the preferred method for diagnosing many types of malignant tumors (cancer of the lung, kidney, liver, pancreas).

Imaging allows you to determine the presence of a tumor, its size, boundaries, localization and degree of damage to nearby tissues.

A CT scan of the head provides important information about the brain, such as bleeding, dilated arteries, or trauma to the skull.

CT scan of the abdominal cavity helps to detect the presence of a tumor, to determine the increase in size or inflammation in nearby internal organs. CT scan clearly shows injuries to the spleen, kidneys, and liver.

The importance of CT cannot be overestimated in the planning of biopsy and radiotherapy.

The method allows you to assess the condition of the bones, spine and bone density.

CT provides important information about injuries to the hands, feet, and other bony structures. The images clearly show even small bones and surrounding tissues.

Advantages of CT:

1. High information content.
2. Painless method.
   The examination does not use medical instruments and autonomous devices, and the passage of X-rays is not felt.
3. Research speed.
   The exact duration depends on the organ being examined. CT of one organ or bone takes only a few minutes /
4. No absolute contraindications.
   Unlike MRI, the method does not affect the operation of implanted life-support devices; it can be performed in the presence of metal implants in the body.

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Computed tomograph. How it works – Health Clinic 365 Yekaterinburg

Multislice computed tomography is a complex diagnostic complex that consists of an X-ray unit (X-ray tube) with a couch that slides into it and a computer workstation that processes the information received into images.

The workstation is located in a separate control room, in which the technologist and the doctor conducting the study work. The technologist and the doctor monitor the procedure, and also have direct visual contact with you, as well as the opportunity to talk with you through speakers and microphones. The X-ray unit produces images of the examined part of the body from different angles, the so-called slices, which are processed and summarized by the workstation.

The principle of spiral tomography consists in the simultaneous performance of three actions: continuous rotation of the source – an X-ray tube that generates radiation around the patient’s body, registration by detectors of radiation passing through a part of the body and continuous translational movement of the couch with the patient along the longitudinal axis.

Different parts of the body absorb X-rays to different degrees. It is this fundamental difference in absorption that makes it possible to distinguish body parts from each other on X-ray film or CT electron images. A special computer program processes this large amount of data to create a cross-sectional image of the body, which is then displayed on a monitor. This technology is called spiral computed tomography.

The principle of operation of a CT scanner is sometimes compared to a loaf of bread cut into thin slices. Just as the collected slices give the opportunity to see the whole loaf, so the many images collected using a computer program will give a very detailed multi-dimensional view of the body part being examined. Moreover, it is possible to study both a part of the body as a whole, and each individual section.

Modern CT scanners are so fast that they can scan large areas of the body in a matter of seconds.
The technology of spiral tomography has significantly reduced the time spent on CT scans and significantly reduced radiation exposure to the patient.

Related topics:

CT scan of the chest, lungs

CT scan of the abdomen and pelvis

CT scan of the colon. Virtual colonoscopy

CT of the head, brain

CT of the paranasal sinuses

CT of the heart.