Pictures eye diseases. Unveiling the Mysteries of Eye Diseases: A Comprehensive Guide
Explore the diverse eye diseases and their causes, symptoms, and treatments. Discover how eye doctors utilize advanced imaging techniques to detect and monitor various eye conditions. Get insights into the most common eye problems and how to manage them effectively.
Decoding Age-Related Macular Degeneration (AMD)
Age-related macular degeneration (AMD) is a leading cause of blindness in older adults. As we age, the macula, the central part of the retina responsible for sharp, detailed vision, can slowly degenerate, leading to a reduction in central vision. It’s estimated that 8.5% of individuals between 43-54 years and 36.8% of those over 75 years have some degree of macular degeneration.
Diabetes and Diabetic Retinopathy
Diabetes is a prevalent condition, affecting 34.2 million people in the United States, with over 7 million unaware they have the disease. Diabetes is the leading cause of new blindness cases among adults in the United States, and the major cause of blindness in people with diabetes is diabetic retinopathy.
Glaucoma: The Silent Thief of Sight
Glaucoma is a serious eye condition that affects an estimated 1.6 million individuals over 40 years of age in the United States. Approximately half of these people are unaware they have the disease. Glaucoma typically develops without any noticeable symptoms, making early detection and treatment crucial to reduce the severity of vision loss.
Ocular Hypertension: When Eye Pressure Rises
Ocular hypertension refers to a situation where the pressure inside the eye, known as intraocular pressure, is higher than normal. Normal eye pressure ranges from 10-21 mm Hg, and ocular hypertension is defined as an eye pressure greater than 21 mm Hg.
Ocular Melanoma: Cancer in the Eye
Melanoma is a type of cancer that typically occurs on the skin, but it can also develop in other parts of the body, including the eyes. When melanoma appears in the eye, it is called ocular melanoma. These melanocytes, the cells that produce the dark-colored pigment melanin, are found in various parts of the body, including the eyes.
Retinal Detachment: A Serious Condition
Retinal detachment occurs when the retina, the light-sensitive tissue at the back of the eye, becomes separated or lifted from its normal position. If not promptly treated, a retinal detachment can cause permanent vision loss. Retinal detachments are more common in nearsighted individuals, those over 50, those with a history of significant eye injuries, and those with a family history of retinal detachments.
Eye Imaging Techniques: Uncovering the Details
Ophthalmologists use various imaging techniques to document and monitor eye conditions. These include standard digital cameras for external eye conditions, slit lamp biomicroscopes to examine the front of the eye, fundus photography to capture the retina, optic nerve, and macula, and optical coherence tomography (OCT) to measure the thickness of the back of the eye. Fluorescein angiography, which involves injecting a dye into the patient’s arm, can also help identify signs of diabetic retinopathy, vein and artery occlusion, edema, and tumors.
Common Eye Diseases and Disorders
Eye diseases and disorders encompass a wide range of conditions, including cataracts, glaucoma, and refractive errors. Ophthalmologists and optometrists specialize in the diagnosis, treatment, and management of these various eye problems, with the goal of preserving and restoring vision.
The Importance of Regular Eye Examinations
Regular eye examinations are crucial for the early detection and management of eye diseases. Many eye conditions, such as glaucoma and diabetic retinopathy, can develop without noticeable symptoms, making regular check-ups essential for maintaining healthy vision and preventing vision loss.
Advances in Eye Care Technology
The field of eye care has seen significant advancements in technology, including the development of specialized imaging tools and treatments. These innovations have greatly improved the ability of eye care professionals to diagnose, monitor, and manage a wide range of eye conditions, leading to better patient outcomes and a higher quality of life.
Collaborating with Eye Care Professionals
Navigating the complex world of eye diseases and disorders can be daunting, but working closely with qualified eye care professionals, such as ophthalmologists and optometrists, is crucial. These specialists can provide personalized care and guidance, ensuring that any eye-related issues are properly addressed and managed.
Empowering Patients through Education
Understanding the various eye diseases and their associated symptoms, causes, and treatment options is essential for patients to make informed decisions about their eye health. By educating themselves and actively participating in their care, patients can play a vital role in maintaining their vision and overall well-being.
The Future of Eye Care: Advancements and Innovations
The field of eye care is constantly evolving, with ongoing research and development leading to new treatments, technologies, and approaches to managing eye diseases. As the understanding of the complex mechanisms underlying various eye conditions continues to deepen, the future of eye care holds the promise of even more effective and personalized solutions for preserving and restoring vision.
AMD is a leading cause of blindness in older people is a condition called age-related macular degeneration. Aging can cause the macula to slowly degenerate and reduce central vision in people over 50 years of age. It is estimated that 8.5% of individuals between 43-54 years and 36.8% of those over 75 years have some degree of macular degeneration.
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Diabetes affects 34.2 million people in the United States, yet more than 7 million people are not aware that they have the disease. Diabetes is the leading cause for new cases of blindness among adults in the United States. The major cause of blindness in people with diabetes is called diabetic retinopathy.
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An estimated 1. 6 million individuals over 40 years of age in the United States have glaucoma. Approximately half of these people don’t know they have the disease. Almost every case of glaucoma develops without symptoms. Early detection and treatment can reduce the severity of vision loss.
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The term ocular hypertension usually refers to any situation in which the pressure inside the eye, called intraocular pressure, is higher than normal. Eye pressure is measured in millimeters of mercury (mm Hg). Normal eye pressure ranges from 10-21 mm Hg. Ocular hypertension is an eye pressure of greater than 21 mm Hg.
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Melanoma is a cancer that usually occurs on the skin. It develops from the cells that produce the dark-colored pigment melanin, which is responsible for our skin’s coloring. These cells, called melanocytes, are also found in other places in our bodies, such as our hair, the lining of our internal organs, and our eyes. When melanoma does occur in the eye it is called ocular melanoma.
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When the retina detaches, it is lifted or pulled from its normal position. If not promptly treated, a retinal detachment can cause permanent vision loss. Anyone can get a retinal detachment; however, they are far more common in nearsighted people, those over 50, those who have had significant eye injuries, and those with a family history of retinal detachments.
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Why Does the Doctor Need a Photo of My Eye?
How ophthalmologists take eye photos
Standard digital camera: A basic 35mm digital camera may be used to document patients diagnosed with an external condition or disorder. Among them: droopy eyelids, Graves’ eye disease, proptosis (when an eyeball protrudes) and skin cancer in or around the eye. “We use standard protocols so the images are consistent from visit to visit,” Steffens says.
Slit lamp biomicroscope: The same tool your ophthalmologist uses to examine your eye. It uses a narrow beam of light and magnifies the view of the front of the eye. Says Steffens: “We’re recording corneal diseases, cataracts and ocular tumors.”
SEE ALSO: Making Prosthetic Eyes That Look Like the Real Thing
Fundus photography: A digital camera attached to a low-powered microscope gives a close-up view of the retina, optic nerve and macula. “You’re using conventional photo techniques here with the help of dilation and the special optics in the fundus camera,” Steffens says. It can also help ophthalmologists monitor changes in a patient’s retina over time — and spot warning signs such as leaky hemorrhages caused by diabetic retinopathy and macular degeneration.
Optical coherence tomography (OCT): This technology involves a low-powered laser that goes through the pupil (although “we don’t even touch the eye,” Steffens notes) to measure thickness in the back of the eye — crucial for determining progression of and treatment for a variety of disorders, including macular degeneration, optic neuritis and glaucoma. The method, he adds, “has become a standard of care.”
Fluorescein angiography: Also using a fundus camera, this diagnostic test requires a patient receive an injection of fluorescein dye in his or her arm just like when blood is drawn. The dye travels through the body to the eye’s blood vessels in about 15 seconds — and the resulting contrast allows doctors to more clearly notice signs of diabetic retinopathy, vein and artery occlusion, edema and tumors.
Types, Causes, Symptoms & Eye Diseases @DocOnline
What We treat
Eye diseases or disorders are of a wide variety. Cataract, glaucoma, refractive errors are major causes of visual impairment and preventable blindness. Cataract is the leading cause of blindness accounting for 66.2% cases of blindness, and 80.7% of cases of severe visual impairment followed by refractive error and glaucoma.
Figure 1: Causes of Blindness
80% of blindness cases in India are curable or preventable.
National Blindness and Visual Impairment Survey India (2015-19) reported that there is a decrease in the prevalence of blindness [Figure 2] and visual impairment in persons above 50 years [Figure 3] because of timely intervention.
Figure 2: Prevalence of blindness in India over the years
Figure 3: Reduction in visual impairment cases in India
Common Eye Problems Among Indians
- Eyestrain [tiredness in the eyes]
- Refractive Errors [short-sightedness, farsightedness, distorted vision] – Uncorrected refractive error is a preventable cause of visual impairment in India
- Dry eye syndrome – Tear glands are not able to make enough tears
- Night Blindness [Nyctalopia] – Difficulty to see in low light
- Conjunctivitis [Allergic / bacterial / Viral] – It is an inflammation of the conjunctiva
- Amblyopia – It is reduced vision in one eye due to vision development disorder
- Eye floaters – Spots [strings, rings, cobwebs] in the vision
- Retina disorders
- Blepharitis – Inflammation of the eyelid causing crusty /dry eyelid, stickiness, grittiness.
- Cataract: A cataract is an opacity within the clear lens of the eye
- Glaucoma – It is a condition where increased intraocular pressure may result in damage to the optic nerve
What Causes Eye Problems?
- Infection, allergy, vitamin deficiency, chemical irritants, genetics, smoking etc are some of the common causes of eye problems
- Cataract – Etiology could be aging, hereditary, UV-Rays, dietary deficiency of vitamin E, C , B, and proteins
- Glaucoma – Too much aqueous production or obstruction of its outflow from the eye causes an increase in the intraocular pressure (IOP), can lead to glaucoma. Over time, high eye pressure can cause irreversible nerve damage and vision loss
- Xerophthalmia – This is the most common cause of blindness in children. It is caused due to vitamin A deficiency
Symptoms Associated with Eye Problems
Various eye symptoms and diseases are listed in the disease in Table 1
Symptoms that demands immediate consultation include
- Severe eye pain
- Change in vision or sudden loss of vision
- Floaters
- Blurred vision
- Watery and red eyes
- The foreign body inside the eye and trauma to the eye
Treating Eye Problems
Various diseases and their probable treatment are given in the table below [Table 1]
Disorder | Symptoms | Treatment |
---|---|---|
Cataract |
| Surgery |
Glaucoma |
| Medical and Surgery |
Eye Strain |
| Artificial tears |
Refractive Errors |
|
|
Watery eye | Excessive tearing | Treat the cause |
Night Blindness | Difficult to see in dark or low light | Treat the cause |
Dry eye Syndrome |
| Artificial tears |
Diabetic Retinopathy |
|
|
Conjunctivitis |
| Antibiotic/ antihistaminic eye drops or ointments |
If you notice difficulty in your sight, constant irritation and should the basic home remedies not suffice, take online eye doctor consultation at your convenience.
FAQ
An ophthalmologist is a medical doctor (eye specialist) who diagnoses and treats eye disorders while an optometrist is trained to perform an eye examination and can prescribe corrective glasses.
When there is severe eye pain, change in vision, sudden loss of vision, floaters, and trauma to the eye.
An ophthalmologist diagnoses and treats eye diseases.
Online test for visual acuity and refractive error are usually accurate.
7 health problems predicted with a look into your eyes
It’s well-known that diseases of the vascular, or circulatory, system increase the risk of cognitive impairment as we age. This system includes veins, arteries, blood vessels and capillaries that carry blood to and from the heart.
“We cannot see the very small blood vessels in the brain through standard brain imaging techniques” like magnetic resonance imaging, said lead study author Jennifer A. Deal, an assistant scientist in the Department of Epidemiology at Johns Hopkins Bloomberg School of Public Health.
Because blood vessels in the eye and brain are similar, Deal and her fellow researchers hypothesized that looking at blood vessels in the eye might explain what was happening in the brain.
Peering into the future
The study began with more than 12,000 men and women at an average age of 57 who were tested for their memory and thinking skills. The participants took another round of exams about six years later and a third round about 20 years after the initial test.
About three years after the study began, the researchers used a special camera to take photos of each participant’s retina, a layer of tissue at the back of the eyes through which light signals are converted to impulses that pass into the brain, enabling us to see.
Deal explained that these photos provided “a snapshot of what is going on in the microvasculature in the eye (and also, we think, the brain) at that point in time, and from that one measure, we can determine if someone has retinal signs indicative of retinopathy,” damage to the retinal blood vessels.
Though most of the participants (95%) showed no signs of damage to retinal blood vessels, 365 people, or 3%, had mild retinopathy. Another 256 people, or 2%, had moderate to severe retinopathy.
Analyzing the data, the team found that participants with moderate to severe retinopathy were more likely to score significantly lower on memory and thinking tests than healthy-eyed participants. In fact, these participants saw their average test scores reduced by 1.22 standard deviation units over 20 years; people with healthy eyes saw declines of only 0.91 standard deviation units. Excluding anyone who missed some of the tests, the researchers calculated a 0.57 standard deviation unit difference between the two groups.
“Although our results were stronger in people with diabetes, we also found a strong and significant relationship of retinal signs and cognitive decline in people who did not have diabetes,” Deal said.
Unhealthy eyes, unhealthy brain
Dr. Rachel Bishop of the federal National Eye Institute said the study results are “not a surprise at all.”
“If the retinal blood vessels are unhealthy, there’s every reason to think that the brain blood vessels are unhealthy as well,” said Bishop, who was not involved in the new study.
“The blood vessel supply is essential to all function, the function of all organs, and so if the blood vessels are unable to do their job, there’s no way that the brain can be functioning as well as a brain that has a good supply.”
Bishop said she likes the idea of screening the eye and retina for negative conditions in the brain, “even if I don’t know quite where it takes us. I think I share a common hope that we could detect things early enough and have interventions early enough to change the course of a negative event. “
After all, she said, the list of diseases and conditions that can be identified by the health of the eye is long — and growing.
Dr. Justin Bazan, an optometrist and medical adviser to the nonprofit The Vision Council, agrees that it is important to study the blood vessels in the eye.
“They do have a direct link and correlation to systemic disease,” he said. As we learn more about the changes that occur with disease, he said, we will be better able to predict cardiovascular events, such as stroke, and “even predict mental changes found in conditions such as Alzheimer’s.”
People usually come in for an eye exam “just to perhaps check their vision or get contacts or glasses,” Bazan said. However, eye doctors can tell them more about their general health.
Diabetes, hypertension, high cholesterol
“Diabetes can be seen in the eyes,” Bazan said. Early changes in people with diabetes include fluctuations in vision.
“They may experience periods where their blood sugar is out of control, which causes changes to the lens inside the eye, and when you cause changes to the lens, it ultimately impacts vision,” he explained. Specifically, a person with diabetes may have blurry vision for a period, and then it returns to normal.
Sometimes, these changes can be attributed to general aging, but the reality could be “uncontrolled systemic disease” such as diabetes, Bazan said.
High blood pressure — too much pressure in the blood vessels — is also “easily observed in the eye,” he said. The damaged blood vessels cause hemorrhages and leaking, both visible during routine eye exams.
“High cholesterol is one of the easiest things to pick up in an examination because it’s on the front of the eye” or the clear structure known as the cornea, on which a contact lens would sit, Bazan said. He explained that “not a day goes by in my office where we don’t detect a buildup of cholesterol.”
Sometimes, heart conditions caused by a buildup of plaque will cause concern during an eye exam.
When plaque builds up in the carotid artery, Bazan explained, “sometimes, those little plaques will break off and then travel into the eye, where they clog arteries in the eye, and that leads to very obvious changes to the vascular structure in the back of the eye. ” A diagnosis would not be made from this little bit of evidence, but the doctor would recommend more tests, including an MRI, to sort out what might be happening.
MS, STDs, thyroid disease and cancer
Multiple sclerosis is often detected when patients have sudden vision loss, Bazan said. Looking into an MS patient’s eye, the doctor would see a change in the color and appearance of the optic nerve. This too would lead to more thorough testing to confirm the diagnosis of MS.
Sexually transmitted diseases also make their presence known in the eyes.
“My first patient in optometry school had conjunctivitis,” Bazan explained, yet the condition was not cured by standard eye drops. This “unresolved conjunctivitis, or pinkeye, that didn’t go away that was unresponsive to typical eye drops used to treat it” was a sign of a bigger problem — in this case the STD chlamydia, which was found only after further tests.
Different types of herpes infection may also cause conjunctivitis. “I’ve also seen syphilis,” Bazan said, explaining that this STD can cause the pupil to change to “an argyle or gray color.” HIV, due to its impact on white blood cells, will also cause visible changes in the retina.
Thyroid disease has several ways of making itself known via the eyes. Because the thyroid controls the hormones responsible, in part, for producing teardrops, many thyroid patients develop dry eye disease, Bazan explained.
Yet thyroid disease also causes the extraocular muscles — the muscles that control eye movement — to become enlarged and stiffened.
“So if you’ve ever seen someone who has bulging eyes, that bulge may be linked to Graves’ disease, which is related to thyroid disorder,” Bazan said, naming former first lady Barbara Bush as an example of someone with this condition.
“If you have a condition where there is systemic inflammation, it is almost always going to manifest in the eye as uveitis,” he said. Uveitis, red and swollen eyes, would occur as a result of lupus and other autoimmune diseases. In fact, any systemic condition that causes inflammation in the body would cause the same inflammation in the eyes.
Finally, cancers, including of the breast, leukemia and lymphoma, may signal their presence in the eyes, even if most people will detect tumors and symptoms of malignancy before their eye doctors do.
Cancer of the basal cells in the sensitive skin surrounding the eye is one of the most common forms of cancer detected, Bazan said. And ocular melanoma — cancer in the cells of the eye — is not as common, but it “definitely does occur, and it is devastating.”
“I think the main point is that going to your eye doctor for your annual eye exam is not just about getting your vision checked or getting glasses or contacts,” he said. “It’s about finding out about the overall health of your eye and in turn the overall health of you.”
Deep learning approach for classification of eye diseases based on color fundus images
- Chapter contents
- Book contents
Volume 1: Computer-Assisted Diagnosis
Computer-Assisted Diagnosis
2020, Pages 25-57
https://doi. org/10.1016/B978-0-12-817440-1.00002-4Get rights and content
Abstract
Retinal images are a key factor for ophthalmologists in the diagnosis of several eye diseases, with a sign of a microvascular retina, which occurs in response to high blood pressure and diabetes. Periodic ophthalmoscopy is the best approach for eye disease screening. However, the number of ophthalmologists available is a limiting factor in initiating screening. With the availability of digital fundus cameras, for automatic analysis of digital images, it can help ophthalmologists diagnose eye disease. On the other hand, computer science, especially in-depth learning has the ability to identify objects in many domains, one of which is the identification of objects in images including images of the retina of the eye. This chapter explains the application of depth learning approach to classification of eye diseases based on color fundal images as inputs. Subsequently, in the Fundus Imaging subchapter, we will discuss the acquisition of relevant Images, major vascular and nonvascular abnormalities, assessment of hypertensive retinopathy and diabetes. In the last section, we implemented convolutional neural networks (CNN) as classifiers for retinal images. The public database used in this study is retinal color images from the STARE dataset which are resized to 61 × 70, 46 × 53, and 31 × 35 pixels. This dataset is categorized into 15 classes of eye diseases. Our experiments show that the highest training accuracy is obtained from input images measuring 61 × 71 and 31 × 35 pixels. The highest test accuracy obtained from the network configuration used is the size of the input image with the smallest resolution of 31 × 35 pixels with an accuracy of 80.93%.
Keywords
Deep learning
Retinal images
Classification
Eye diseases
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The 4 Most Common Age-Related Eye Diseases
By age 65, one in three Americans have some form of vision-impairing eye condition. There are four major age-related eye diseases (AREDs) that affect seniors: glaucoma, cataracts, macular degeneration and diabetic retinopathy. Learning about the symptoms of and treatments for each of these conditions can help you protect your vision and that of an aging loved one.
Glaucoma
Glaucoma occurs when the pressure within the eye is elevated, which can damage the optic nerve and result in vision loss and blindness. There usually are no initial symptoms, so as many as one million people may have glaucoma without realizing it. This condition is one of the main causes of blindness in the United States.
At first, glaucoma yields no obvious symptoms. However, as the disease progresses, a person with glaucoma may notice their side or peripheral vision gradually failing. Sufferers may experience worsening tunnel vision if left untreated.
There are many different types of medications (in eye drop and pill form) that are used to treat glaucoma. In some people, however, medications alone do not successfully control increased eye pressure, and surgery needs to be performed. One type of surgery called trabeculoplasty uses a laser to improve the flow of fluids out of the eye thereby reducing pressure. This can be done in your doctor’s office. There is also conventional surgery called trabeculectomy in which your doctor creates a new drainage path in the eye, under the eyelid.
Risk factors for glaucoma include age, family history of glaucoma, the use of steroid medications and near-sightedness.
Read: Glaucoma Can Steal 40% of Vision Before a Person Notices
Cataracts
A cataract is a clouding of the eye’s usually transparent lens. The lens is composed of water and protein, but if the protein clumps together, it can start to obscure transmission of light through the lens. If the cataract worsens and begins to severely affect vision, surgery may be necessary to remove the cloudy lens and replace it with a new one.
People with cataracts often complain about glare, cloudy/fuzzy vision, double vision in one eye or halos around lights. Surgery is the only way to correct vision loss caused by cataracts.
Getting older is a major risk factor for cataracts, and women are at slightly higher risk than men. People who smoke, do not protect their eyes from the sun and have a family history of cataracts are more likely to develop them as well.
Read: Cataracts: Getting the Big Picture (and a Clearer One, Too)
Macular Degeneration
Macular Degeneration (MD) diminishes sight in a dramatic way: It affects one’s central vision. Although people with MD rarely go completely blind because of it, many find it difficult to read, drive and perform other daily functions. This condition affects the macula, an area at the center of the retina that is responsible for focused, central vision.
In the early stages of MD, there are usually no visual symptoms. A person’s central vision will eventually appear wavy or blurry, and in advanced cases it may disappear completely. However, peripheral vision usually remains intact because the rest of the retina is still healthy. Even with some remaining vision, it can still be difficult for those with MD to detect fine details and colors.
MD is considered an incurable eye disease, but there are a few treatments that can help slow its progression. People with macular degeneration can be treated with laser surgery and anti-angiogenic drug injections. Low-vision devices are also helpful for maintaining an active and independent lifestyle in spite of visual changes.
Age is the biggest risk factor for developing MD. It is estimated that 6.5 percent of Americans age 40 and older have some degree of macular degeneration. Family history, race (whites appear to have a higher risk than blacks or Hispanics), high blood pressure and smoking are other risk factors.
Read: Age-Related Macular Degeneration: Information for Caregivers
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Diabetic Retinopathy
This potentially blinding disorder is a complication of diabetes. Diabetes causes abnormal changes in the retina’s blood vessels, causing them to become leaky and grow where they should not. These new vessels tend to break and bleed. As they try to heal, the damaged blood vessels will contract and detach the retina.
Symptoms of diabetic retinopathy include shadows or dark objects that appear to “float” across your field of vision, blurred or distorted vision, partial loss of vision and pain in the eye.
Consistently high blood sugar and high blood pressure are associated with retinopathy. Type 2 diabetics who use the medicine rosiglitazone (brand names Avandia, Avandamet and Avandaryl) to manage their blood sugar may be at higher risk for problems.
There is no cure for diabetic retinopathy. However, laser treatment (photocoagulation) is usually very effective at preventing vision loss if it is done before the retina has been severely damaged. Surgical removal of the vitreous gel (vitrectomy) may also help improve vision if the condition is caught early enough.
Read: Diabetic Retinopathy Can Lead to Blindness
Eye Tests Every Senior Should Have
Age-related eye diseases are diagnosed through an exam performed by an ophthalmologist. A comprehensive eye exam should include at least the following three tests.
- Visual acuity test: The familiar lettered eye chart measures how well you see at various distances.
- Pupil dilation: Drops are placed in the eye to widen the pupil. This allows the doctor to view more of the retina and look for signs of disease. After the examination, close-up vision may remain blurred for several hours.
- Tonometry: This test determines the fluid pressure inside the eye, and there are many methods of doing so. An “air puff” test is the most common way to screen for high intraocular pressure. It is a painless process in which a small jet of air is shot against the cornea. Other more involved tests may be required to obtain more accurate readings.
Most age-related eye conditions must be detected and treated early on to prevent lasting damage. A comprehensive eye exam is recommended every one to two years, depending on a person’s age and unique risk factors. These exams are vital for catching diseases like glaucoma and MD that have no obvious symptoms in the early stages. If you or a loved one is experiencing noticeable changes in vision, it is crucial to make an appointment for an eye exam as soon as possible.
Digital Retinal Photography – Orlando FL
Digital Retinal Photography – Orlando FL | Vision Health Institute
Please be aware of our COVID-19 guidelines – masks are required inside the office. Only one guest accompanying you to the appointment if necessary.
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Have you ever seen the inside of your eye? See what the doctor sees when he looks into your eyes! We feel that it is important that our patients understand what we are looking for, and what we see when the doctor looks inside your eyes.
Many eye problems can develop without warning and progress with no symptoms. Early on, you might not notice any change in your vision. However, diseases such as macular degeneration, glaucoma, retinal tears or detachments, central retinal vein or artery occlusion, optic strokes, as well as other health problems such as diabetes and high blood pressure, can be detected with a through retinal examination utilizing a digital retinal camera.
Digital retinal photography consists of a digital camera system that takes a photograph of your retina. Here is a summary of the benefits of Digital Retinal Photography:
- A scan to confirm a healthy eye or detect the presence of disease.
- An overview or map of the retina, giving your eye doctor a more detailed view than he can achieve by other means.
- The opportunity for you to view and discuss the images of your eye with your doctor at the time of your examination.
There is no need to wait for results, our digital camera gives us the images within seconds for review. By looking at digital photos from previous years, your doctor can look for changes over time and determine if more aggressive treatments are necessary.
We recommend that all our patients receive this test. It is especially important for patients with a history of high blood pressure, diabetes, retinal diseases, flashes of light, floaters, headaches and those with a strong glass prescription.
90,000 Ophthalmologist named the consequences of COVID-19 for the eyes – RBK
Photo: Laurent Gillieron / EPA / TASS
Coronavirus can exacerbate eye diseases, warned Associate Professor of the Department of Eye Diseases of the National Medical and Surgical Center.NI Pirogova Irina Leschenko in an interview with Sputnik radio.
In particular, an ophthalmologist does not exclude an acute manifestation of a disease such as allergic conjunctivitis in those who have had COVID-19.
The doctor explains the link between fear and risk of contracting COVID-19
“We noted that those who have already had allergic eye diseases, then at the time of the coronavirus disease there are no manifestations, but in three weeks an exacerbation of allergic conjunctivitis may occur,” she said.
In addition, COVID-19 can “wake up” a chronic disease – glaucoma. Patients who have had a coronavirus infection and have this eye disease should see a doctor.
Eye pterygium treatment
Pterygium (pterygoid hymen) is a formation on conjunctivitis that grows into the cornea if untreated.
It is often found in people of retirement age.At the initial stage, there is no discomfort, but later on there is redness, tearing, irritation. In severe cases, loss of vision is possible.
The reasons for the development of the disease
Today there is no consensus on the causes of pterygium, but it can be provoked by:
allergic conjunctivitis;
prolonged eye strain;
genetic factors;
dry air;
long-term work at the computer;
ultra-violet rays;
infections and injuries.
Pathology impairs the characteristics of the tear film, which leads to chronic irritation that turns into inflammatory processes. Timely seeking medical help allows you to avoid infection and prevent the development of pathology in time.
Symptoms of pterygium
An opaque triangular formation can be seen on the eye, similar to a yellowish film with a sharp end directed towards the pupil.The blood vessels are clearly visible. At the initial stage, the pathology does not bring any problems, but later the symptoms become distinct:
tearing;
the cornea darkens;
vision falls;
itching and burning;
discomfort and dryness of the eyes.
Already at the first manifestation of the disease, you need to urgently seek medical help from an ophthalmologist.
Classification of pathology
The pterygium can be progressive or stationary. The diagnosis is made by the condition of the patient’s vessels:
the first degree – education is transparent and atrophic, progression is minimal;
second degree – partial viewing of vessels with protruding formation;
third degree – the formation is opaque and highly active, the vascular network is clearly visible.
Diagnostics of the pterygium
The procedure is simple due to the obvious presence of a neoplasm on the eye. An important differentiation task is to distinguish pterygium from other diseases with similar symptoms. In case of doubt, it is necessary to carry out biomicroscopy – a special procedure for studying the structure of a neoplasm using a slit lamp. In extreme cases, a biopsy is done.
Treatment of pterygium of the eye
Only surgical intervention gives effective results in the treatment of the pterygoid hymen.The most favorable predictions are made at the first manifestations of pathology, until the paternal zone of the cornea is closed. The use of medicines or folk remedies can only aggravate the situation.
Prevention methods
The most effective method of preventing the development of pathology is to protect the eyes from harmful effects. In summer, it is recommended to wear goggles that protect against ultraviolet radiation, which is considered the main cause of pterygium.
When the first symptoms appear, you should seek the advice of an ophthalmologist. After the examination, he will give recommendations for prevention. Sometimes surgical intervention is not required due to the absence of an increase in pathology.
Patients with pterygium need to undergo regular medical examinations to observe the neoplasm, p If a growth of is detected, the doctor will be able to send for operation on time, increasing the chances of successful treatment.
After surgery , it is important to go to the doctor on time for examination to monitor possible changes and seek help if any changes or symptoms appear that were not previously observed.
Recovery period
In the postoperative period, the patient must undergo recovery under the supervision of a physician. Additional drugs are prescribed depending on the method of surgery: anti-inflammatory or antibacterial.This helps to prevent the manifestation of complications. Additionally, drops may be prescribed for moisturizing due to increased sensitivity of the cornea in the postoperative period.
Note! With pterygium, tearing begins, it hurts to open the affected eye due to the development of corneal syndrome a . After surgery, these symptoms disappear completely.
The first few days after removing the pterygium, vision will be blurry.The entire recovery period will take several weeks, after which vision will be fully restored. But it is important to remember that if the recommendations are not followed, relapses occur, in addition, in rare cases:
degeneration into a malignant tumor occurs;
perforation of the eyeball or retinal detachment;
scarring.
In order to avoid such situations, it is necessary to listen to the advice of the attending physician and strictly follow the instructions.
90,000 why at the end of the 19th century the Kazan province and the Volga region were covered by the trachoma epidemic
A part of the exposition of the Museum of the Kazan Ophthalmological School, which recently opened in a building next to the Republican Ophthalmological Clinic on Butlerova Street, is devoted to the topic of the trachoma epidemic. The Tatar-inform correspondent attended the opening of the museum.
Trachoma is a chronic infectious eye disease that affects the thin transparent membrane (conjunctiva) and the cornea, causes suppuration, inflammation and, if not treated promptly, leads to blindness.The disease quickly spreads through hands, household items, clothing. In the conditions of the low level of hygiene in Russia at the end of the 19th century, hundreds of thousands of people, mainly representatives of the poor, were infected with eye trachoma.
The Tatar villages of pre-revolutionary Russia were completely covered by an epidemic, as evidenced by the references in the works of Tatar writers of that time. For example, in his famous novel “Tiren tamyrlar” (“Deep Roots”) Galimzyan Ibragimov writes:
Ahmi rubbed his bleeding eyes with a dirty sleeve.
If a person was able to distinguish only silhouettes, it is not difficult to understand that due to illness his eyesight has deteriorated. Alfiya Nugumanova also notes that writers and representatives of art mention trachoma in their works. “Yes, it is found in the literature, because the population of the Kazan province has suffered greatly. Seeing how many people suffer next to them, they, of course, could not remain silent, ”she says.
PHOTOS: wards for patients with trachoma (1930s)
“The world has known about such a disease as trachoma for a long time.Records of this disease were found on the papyri of Ancient Egypt. The causative agent of the infection prevailed in countries with hot climates, where it was impossible to wash hands and there was a low level of hygiene culture. As a result, this dirt got into the eyes, ”says Alfiya Nugumanova.
According to the scientist, sexual transmission cannot be ruled out, since the pathogens of trachoma – chlamydia – are also the cause of the venereal disease chlamydia. Chlamydia affects the respiratory, cardiovascular, musculoskeletal, genitourinary systems, and organs of vision.The infection leading to trachoma was discovered in 1907 by the Czech scientist Provachek.
Where did trachoma come from and how?
Trachoma first appeared in Europe during the time of Napoleon. French soldiers find out about the disease after a campaign in Egypt. Thus, trachoma is brought from Egypt to Europe by the military, then it spreads among the common population.
There is also information that trachoma arose on the territory of Russia in the XII-XIII centuries. The troops of Genghis Khan, passing through Central Asia, contracted trachoma, then left foci of infection on Russian territory from the lower Volga to the Kama and Oka.Therefore, before the revolution, this infection was especially common in the Volga and Kama regions. Especially many cases of the disease were recorded among the Tatars, Udmurts, Chuvash, Mari. There were also trachoma foci in the south of Ukraine, Crimea, and the North Caucasus. In 1913, the number of trachoma patients reached a million.
“The wars that took place between states during that period contributed to the spread of infection throughout the world. Moreover, it was a rather insidious disease – even once having been cured, a person was not protected from re-infection, since the body did not develop immunity to infection.But the worst thing about this disease is the speed of its spread. A focus that emerged in one place covered the masses in a short time, and such outbreaks occurred constantly, ”says Alfiya Nugumanova.
According to the scientist, KSMU specialists studied historical references, archival data, documents, statistics reports, which indicate that the highest incidence of trachoma was recorded in Kazan province.
“Our population was multinational, so the disease spread quickly.There is even such statistics: among Tatars, Mordovians, Chuvashes, it was more common than among Russians. The Russian peasants have about 18%, the Tatars – 44% and about 75% – among the Chuvashes. There were differences depending on the strata of the population: in families with higher incomes, hygiene standards were met, so the incidence rates were lower. And the poorer population, living tightly under one roof, using common household items, became infected more and faster. It was customary for the Tatars to use one common towel for the whole family, which led to a rapid infection of the household.This disease did not spare neither men, nor women, nor the elderly, nor children. Therefore, trachoma is called an epidemic. If we look at scientific research on the fight against trachoma, we will see that up to 50 percent of the population suffered from this disease, ”said Alfiya Nugumanova and explained that such data are given in an article by Valentin Adamyuk, the son of the founder of the Kazan ophthalmological school, Professor Emilian Adamyuk.
PHOTO: Alfiya Nugumanova with the passport of Emilian Adamyuk found in Moscow.
The first Russian trachomatosis institute was founded in Kazan
On November 14, 1922, the first Russian scientific medical institution to combat trachoma was founded in Kazan. As the specialist of the Republican Medical Information Center Oksana Korneva said, the basis for the creation of the trachomatous institute in Kazan was laid by the famous scientist, professor, head of the Department of Eye Diseases of the Faculty of Medicine of Kazan University Emilian Adamyuk (1839 – 1906).
“This disease really had the scale of an epidemic, it was very quickly transmitted through household items. There is even an old photograph of a woman wiping a child’s tears with her handkerchief. If the mother was infected, then the infection could be transmitted in this way to her child. The Kazan ophthalmological school was founded by Emilian Adamyuk. After graduating from the medical faculty of the Kazan Imperial University, he leaves for a business trip abroad for two years, is an internship in the best eye clinics in Europe.Upon his return, in 1870 he was appointed head of the Department of Eye Diseases of the Medical Faculty of Kazan University. This year is considered the year of foundation of the Kazan Ophthalmological Hospital. He organized a clinical base for the teaching of ophthalmology as a scientific discipline. He not only lectured to students, but also researched all practical cases, taught the basics of surgery. Carrying out a large-scale research, medical, teaching activity, he also dealt with trachoma issues.Having compiled a trachomatous card, he recorded all cases of diseases in it. And he dealt with treatment issues in the 1st Kazan Ophthalmological Clinic, created in 1900 with his personal active participation, ”said Oksana Korneva.
Professor Adamyuk appealed to the university administration and the Zemstvo Office with a request to create an independent clinic for the treatment of trachoma, as he saw that day after day the number of those suffering from this disease was increasing. Thus, in 1922, the Emilian Adamyuk Trachomatous Institute was established.
PHOTOS: training courses for nurses for the treatment of patients with trachoma (1926)
“The institute had a hospital for 40 beds. Professor Vasily Chirkovsky, one of Adamyuk’s students, is appointed director of the trachomatous institute. In 1926, he organized training courses for nurses in the treatment of trachoma patients. During these years, special trachomatous detachments were organized, which made house-to-house visits in the districts of Tatarstan and identified cases of the disease. A journal on trachoma is published.Chirkovsky describes in detail his rich experience in identifying and treating such patients in his monograph, published in 1932. It was so popular in the medical community that it was reprinted five times. For the fight against trachoma, Chirkovsky was awarded the Stalin Prize, ”said Oksana Korneva.
As Oksana Korneva said, the activities of the trachomatous institute were not limited to trachoma treatment, attention was also paid to other problems and eye diseases. And during the Great Patriotic War, all forces were devoted to the treatment of the wounded.Many employees of the institute, doctors were drafted into the active army, and those who remained in the rear became consultants in Kazan evacuation hospitals and performed operations.
Victory over trachoma
Trachoma began to recede in the post-war years. According to Alfiya Nugumanova, such well-known doctors as Agababov and Murzin made their significant contribution to the fight against this dangerous disease.
“Effective methods of treating this disease were found, measures were taken to alert the population, information work was organized, and conversations among schoolchildren were organized.Effective chemicals are used – albucids, later tetracycline appears. Scientists have tried to come up with more and more effective treatments. Perhaps they also drew on the experience of other regions and countries, ”said Alfiya Nugumanova.
ON PHOTO: Museum exhibits
According to Oksana Korneva, in 1964, it was announced about the complete victory over trachoma on the territory of the TASSR. In this regard, the Ministry of Health of the republic issued a decree on the transformation of the trachomatous institute into the Republican ophthalmological clinic.
Further activities of the Kazan Ophthalmological School
In the 60s of the last century, the hospital acquired new directions of activity and the Kazan Glaucomic School was founded.
It is believed to have been founded by Wurgaft and Nesterev. They study the photogenesis of glaucoma, methods of its treatment, and there are many works devoted to this disease. New instruments for the treatment of glaucoma are being introduced. At the department of GIDUV, under the leadership of Professor Wurgaft, training cycles for doctors were organized.Doctors from all over the country tried to go through this cycle in Kazan. The main innovation of that time: Professor Wurgaft handed each doctor a special case with a set of diagnostic tools. These instruments were made by his order at the Kazan Medical Instruments Plant.
Later, microsurgical operations were started in Kazan. The 1980s are considered the year of the beginning of microsurgery treatment at the Kazan Ophthalmological Hospital.
Descendants of Adamyuk came to the opening of the museum
The opening of the museum of the Kazan ophthalmological school was timed to 180th anniversary of the birth of Emilian Adamyuk.The museum displays instruments used by doctors for the last century for the diagnosis and treatment of eye diseases. For example, the manometer for measuring eye pressure is an invention of Professor Emilian Adamyuk. In addition, here you can see the scientific works of the scientist, samples of lenses for spectacles, a manual ophthalmoscope, tonometric sets and much more.
PHOTOS: Museum exhibits
The great-grandchildren of Emilian Adamyuk came to Kazan for the opening of the museum, who brought the preserved personal belongings of their ancestor.Great-grandchildren admit that for many years they did not know about their outstanding relative and about the family heirlooms that have survived after him. Vladimir Chibisov from Moscow helped Roland and Barbara Kloss from Austria to learn about their roots. It was he who discovered the personal belongings of Adamyuk, once transferred to his mother for safekeeping by the professor’s descendants.
“In my mother’s apartment I found Adamyuk’s professorship certificate, his scientific works. Interested, began to study the origin of the famous doctor. I found Roland and Barbara Kloss on social networks, ”said Vladimir Chibisov.And Chibisov himself was approached by Alfiya Nugumanova.
PHOTOS: from left to right: Vladimir Chibisov, Barbara Kloss, Roland Kloss
The discovery of distant ancestors in Russia came as a big surprise for Roland.
“We knew nothing about him. Having learned about this, I began to study the pedigree. It turned out that Emilian Adamyuk had four children, one of the daughters married an Austrian officer and moved to Vienna. Thus, the Adamyuk family was continued in Austria, we are one of his heirs.I am proud that I have such roots ”, – said Roland.
He donated some historical exhibits telling about the Adamyuk family to the museum of the Kazan State Medical University and the museum of the Kazan ophthalmological school.
90,000 jumps and dots – National Research University Higher School of Economics
Eye movements can tell scientists about human neurological diseases, the mechanisms of abstract thinking, and can even help ascertain death.The technique of studying how the eyes move is called eye tracking. Mikhail Pokhodai, an intern researcher at the HSE Center for Neuroeconomics and Cognitive Research, spoke about her within the framework of the project “A University Open to the City: Lectures by HSE Young Scientists at the ZIL Cultural Center”.
Eytracking from Aristotle to the present day
People have always strived to study the eyes as one of the most important organs of the human perception system: even Aristotle in his writings described the mechanism of their movement.However, up until the 19th century, the eyes were mainly viewed from a physiological point of view, trying to understand how to treat eye diseases, restore visual acuity, and so on. The eye-tracking technique (or oculography), which originated in the late 19th century, sets itself the task of collecting and analyzing data on how the eyes move. In other words, eye-tracking attempts to study how the eyes move, for example, while reading, or when viewing visual stimuli. The study of eye movement is also necessary in the diagnosis of neurological diseases, the study of abstract human thinking, in usability research in the field of marketing, for understanding the fundamental foundations of the processes of perception, mechanisms of attention and the generation of language.
In 1879, French physician and politician Louis Émile Javal, who studied human eye movements while reading, discovered that the eyeballs did not move smoothly as previously thought. With the help of a stethoscope, which was applied to the subject’s eye while reading the printed text, Javal heard the movement of the eyes. It turned out that they never move evenly over the text, but make short stops (fixations), and abrupt movements – saccades.
The main points of interest of a person when studying another face – nose, mouth and eyes
At the beginning of the 20th century, American experimental psychologists Raymond Dodge and Thomas Sparks Klein built a relatively accurate non-invasive (no direct contact with the eyeball) eye tracker.It was a bulky, long exposure camera. The participant’s eyes were filmed in one plane (horizontally), then on a photographic plate it was possible to see the position of the eyeball in space.
Subsequently, scientists Judd, McAlister and Steele improved the eye tracker by adding video recording capabilities. This made it possible to record the eyes not only in the horizontal plane, but also in the vertical one.
In 1935, American psychologist Guy Thomas Buswell went even further, proving that each person perceives the same visual stimulus differently.The scientist deduced such a concept as a “zone of interest”. This means that when studying, for example, a painting with a castle, different people (depending on their interest) consistently pay attention to specific areas. Someone will first look at the windows of the castle, someone will first pay attention to the trees around the castle, and so on. Later, the Soviet physiologist Alfred Yarbus, collecting and analyzing the oculomotor data of people, saw that, depending on the participant in the experiment, the tasks of his eye movements radically change.In addition, by showing the subjects images of human faces, he deduced the canonical perception of the face – the gaze is fixed mainly on the eyes and the area between the nose and mouth. In other words, the main points of interest of a person when studying another face are the nose, mouth and eyes.
With the advent of the first personal computers, the work of researchers was greatly simplified. Advances in technology have made it possible to use high-speed video cameras. Scientists now receive up to 2,000 frames for every second of a photo of the eye for further analysis.This makes it possible to study eye movements at the micro level, since every second the human eye makes about 3-4 fixations connected by saccades. For comparison, at the time of Buswell, scientists had to process all this huge array of information manually, transfer data from a video recording to paper for further analysis.
The eye is in constant motion
Eye movements can be classified into three types. The first of which is fixation movements of the eyes, which in turn are subdivided into tremors – small physiological twitchings of the eye that occur during fixations, and drift.The eyes of a healthy person are constantly in motion, even when he looks at one point. Eye twitching (tremor) occurs due to light stimulation of the eye muscles, and without special equipment, eye tremors cannot be noticed. But with the help of an eye tracker, researchers can detect eye fluctuations, and can, for example, diagnose brain death. When a person’s brain dies, the eyes stop wobbling. Also, the analysis of tremor allows you to monitor the condition of a patient under anesthesia or in a coma.Some neurological disorders are accompanied by abnormal tremors (Parkinson’s, multiple sclerosis).
The human eye sees nothing for about 150 milliseconds. This time is necessary for the brain to process information
Periodically, the eye “floats away” from the fixation point (the point at which it focuses) in different directions – this phenomenon is called ocular, or ocular, drift. In some neuralgic disorders, drifting becomes abnormal.
Drift also informs scientists about abstract human thought processes. For example, when the subjects read positive words, the ocular drift went to the right and up, and when reading negative words, it went left and down. When the participants in the experiment saw numbers from 1 to 4, their eyes drifted to the left, and from 6 and above to the right.
The second type of eye movement is stationary eye movements. These movements include gaze – they connect several fixations and saccades, and fixations – stop the eyes at one point.Saccades – rapid movements of two eyes in the same direction – connect fixations. The saccade speed is measured in degrees of visual angle per second and reaches colossal values. The maximum speed of saccades is up to 600 (and according to some sources 900) angular degrees per second. This is an indicator of how quickly a person is able to switch from one object to another. During the initiation of the saccade, a person cannot influence the trajectory of the eye movement and its final stop (fixation).
Visual information (what a person sees at a particular second) is the result of the last 3-4 fixations analyzed by the brain. A curious feature of saccades is that 50 milliseconds before its start and immediately during initiation (movement – it lasts from 40 to 120 milliseconds), human visual perception is completely turned off, that is, for about 150 milliseconds, the human eye does not see anything. This time is necessary for the brain to process information.During the saccade, vision is suppressed, and new information comes only with the next fixation. However, a person is not able to notice this complex mechanism and temporary blindness due to high speeds.
The third type of eye movement – gaze shifting – is responsible for rapid gaze movements within the range from 1 to 50 angular degrees, arising during visual fixation of an object (stimulus).
Also, the researchers attribute the dilation of the pupils to eye movements. The technique for measuring the diameter of the pupil is called pupillometry, it is used in some eye trackers as a reference point for the position of the eye.Pupil dilation is correlated with an increase in the difficulty of the task; it responds well to interest, excitement, excitement. The pupil reacts from birth and its dilation is an uncontrolled human activity.
The gaze of professional football players, compared to beginners, focuses more clearly on the necessary details (such as the position of the player), while the gaze of the beginner is fixed on details that sometimes do not carry any useful information about the game
In a separate type of eye movement, scientists attribute tracking eye movements (PDG) – the ability of the eyes to move not in jumps and dots, but, as was assumed in the 19th century, smoothly, as if following an object.Tracking movements are important for maintaining focus. If a person needs to track a target, it is much easier to do this with the help of smooth movements, rather than constantly fixing and analyzing new information. PDG comes into operation only in the presence of a moving object.
Smooth eye movements are realized using completely different mechanisms, saccades and fixation no longer play a role. Scientists tend to believe that man acquired this skill as a result of evolution, when the need arose to hunt game.Perhaps that is why people have more developed horizontal than vertical tracking eye movements (PDG), and also descending PDGs in humans are better developed than ascending ones.
Diseases such as autism, schizophrenia, alcohol and drug intoxication are associated with a violation of PDH.
What the eyes are exploring now
Modern oculographs (eye trackers) are binocular (record both eyes) and monocular (record one eye). But most often they can work in two modes.In addition, oculographs are divided into invasive (having contact with the eye) and non-invasive. With some types of invasive oculograph, a metal lens is applied to the eye, connected either to electrodes or directly to the recording device itself. The readings of invasive eye trackers are very accurate, but for the subject the procedure is very painful. Therefore, more often modern laboratories are equipped with electrooculographs and optical oculographs.
Electro-oculographs are mainly used in medicine to diagnose various diseases.They collect oculomotor data on the ratio of electrical potentials from electrodes that are placed on the skin around the eyes. The range of application is very wide, but the accuracy is poor, since it is difficult to determine the direction of the subject’s gaze during the demonstration of the stimulus.
Optical oculographs record eye movements on a camera using various methods. Some oculographs record the position of the pupil, some – the position of the center and Purkinje reflection – the reflection of infrared light from the cornea.A modern optical eye tracker consists of two computers, one of which is responsible for a highly sensitive camera, the other for the presentation of stimuli. There are also various options for head eye trackers (mounted on the head) that can be used, for example, by studying the eye movements of professional football players during their play on the field.
A similar study was conducted a couple of years ago with the participation of the famous football player Cristiano Ronaldo. The result of the study was that the gaze of professional football players, compared to beginners, focuses more clearly on the necessary details (such as the position of the player), while the gaze of a beginner is fixed on details that sometimes do not carry any useful information about the game.The researchers concluded that a professional, unlike a beginner, does not react to what happened during the game, but tries to predict further actions and act accordingly.
Blepharospasm – treatment, symptoms, causes, diagnosis
The first mention of blepharospasm and spasm of the lower part of the face was stated in a painting from the 16th century called “Onlooker”. At that time, and for the next several centuries, patients with such spasms were considered mentally inadequate and were often sent to insane asylums.Little progress in the diagnosis and treatment of blepharospasm was only made in the early 20th century when Henry Meige, a French neurologist, described a patient with spasms of the eyelids and midface, facial hemispasm, a condition now known as Meige’s syndrome. At almost the same time, the first medical procedures were introduced, including the injection of alcohol into the facial nerve, neurotomy, and neuroectomy.
Normally, an adult blinks 10 to 20 times per minute. The number of flashes tends to decrease when reading or using the computer.An increase in the frequency and strength of eyelid closure is known as blepharospasm. It is focal dystonia that occurs in adults with repeated spasms of closing the eyes; the circular muscle of the eye contracts involuntarily and forcibly. Periods of cramping can last from a few seconds to several minutes and are often repeated. The severity of the condition ranges from increased blinking with rare spasms to severe with severe painful spasms. Sometimes the spasms can be so severe that they can cause serious visual impairment.
Etiology
Blepharospasm is a subtype of focal dystonia. Most cases of blepharospasm are idiopathic and are called benign or primary blepharospasm. In the case of blepharospasm, involuntary closure of the eyelids occurs due to spasms in the circular muscle of the eye. This distinguishes blepharospasm from muscle paresis levator palpebrae , in which there is apraxia and this condition occurs in Parkinson’s disease. The etiology of blepharospasm is not yet known.It was thought that blepharospasm could be caused by abnormalities in the basal ganglia, but this has not been proven. At the same time, there is reason to believe that several cortical and subcortical structures can participate in the development of blepharospasm. The circuit that participates in the blinking process includes the sensory peripheral part, the central control zone in the brain, and the motor part. It is believed that a defect occurs in this chain of neurons. The exact mechanism is not known, but it is likely that more than one defective locus exists, leading to neurotransmission overload and the development of blepharospasm.
There have been cases of secondary blepharospasm due to a specific organic disease. Ocular causes of secondary blepharospasm include:
- Injuries to the eye (mechanical, chemical or thermal) – in particular to the cornea – cause acute blepharospasm.
- Blepharitis.
- Conjunctivitis, iritis, keratitis.
- Dry eyes.
- Other chronic diseases of the eyelids or eyes
- Glaucoma or uveitis.
Blepharospasm can also occur in systemic conditions:
- Multiple sclerosis
- Focal traumatic brain injury or tumor
- Infections (viral encephalitis, Reye’s syndrome, subacute sclerosing panencephalitis, Jacob-Creutzfeld disease, AIDS, tuberculosis, tetanus).
- Atypical Parkinson’s disease / multiple systemic atrophy / progressive supranuclear palsy.
- Side effects of medications – eg olanzapine, levodopa.
- Tardive dyskinesia.
- Tourette’s syndrome.
- Cerebral palsy
There is evidence of some genetic determinism, although the likelihood of blepharospasm being inherited is only 5%.
Epidemiology
Prevalence estimates vary, with incidence rates ranging from 16 to 133 per million. Blepharospasm is more common in women than in men. This condition most often occurs over the age of 50.
Symptoms
- Spasmodic eye closure usually occurs in bright light, reading or watching TV. Driving, fatigue and stress can also trigger the development of cramping.
- Concentrating on the task at hand can reduce the intensity or frequency of cramps. Talking, whistling, touching your face, walking, and relaxation can also reduce cramping. (Most people blink more often during a conversation than at rest, while in people with blepharospasm, the opposite is true.)
- Spasms can be associated with eye irritation, hemifacial spasm, tics.
- At night, cramps usually do not occur.
- In idiopathic blepharospasm, symptoms are usually bilateral, although sometimes they can be on one side.
Diagnostics
Differential diagnosis of blepharospasm should be done with the following conditions:
- Hemifacial spasm. It is sometimes difficult to distinguish blepharospasm from hemifacial spasm.With facial hemispasm, the frontal muscles contract simultaneously with the orbicular muscle, and it turns out that the eye is closed, and the brow ridge is not changed. Such a contraction cannot be done arbitrarily.
- Ptosis.
- Apraxia opening century
- Blepharitis.
- Myasthenia gravis.
Associated diseases
- Blepharospasm may be associated with oromandibular dystonia, characterized by recurrent spasms of the face, nasopharynx, and larynx.This can lead to spasms of the lips and jaw, chin, which leads to problems with speech and swallowing. In patients, oromandibular dystonia can develop after blepharospasm and vice versa; in cases where blepharospasm is associated with involuntary movements of the lower face and / or jaw muscles, this condition is called Meige syndrome.
- Bruegel’s syndrome is characterized by blepharospasm involving the muscles of the mandible and neck.
Diagnostic tests
To exclude reflex blepharospasm, additional examinations (MRI, CT, EMG) are necessary, since it is necessary to diagnose the underlying neurological disease.
To determine the degree of blepharospasm, a scale is used to assess functional impairment in these patients. This scale is subjective. It correlates well with the Yankovich rating scale, an objective assessment of the severity and frequency of involuntary eyelid movements.
Treatment
- Blepharospasm can be a reflex reaction to the underlying disease (most often, with diseases of the surface of the eye and this must be excluded at the very beginning of treatment)
- Wearing dark glasses can reduce exposure to bright light and prevent the awkwardness of onlookers.
- Voluntary maneuvers such as eyelid stretching, neck tension, talking, yawning, singing.
- Patients with severe blepharospasm should not drive
Drug treatment
Although drugs from various classes have shown some efficacy in treating blepharospasm, drug therapy for blepharospasm is generally based on the following pharmacological unverified hypotheses:
- cholinergic excess,
- GABA hypofunction,
- excess dopamine.
Pharmacotherapy is usually less effective than botulinum toxin injections and is mainly of an auxiliary nature.
The use of antispasmodics and benzodiazepines has little effect. There has been some positive effect from the use of tetrabenazine.
Botulinum toxin injections
Botulinum toxin type A injections into the circular muscle of the eye are the preferred treatment for blepharospasm. Systematic studies by Cochrane have shown that botulinum toxin treatment was very effective in helping up to 90% of patients compared to placebo.Botulinum toxin interferes with the release of acetylcholine from nerve endings, and therefore relieves spasm in the muscle where the toxin was injected for a certain period of time.
The initial dose is usually 10-20 units at the injection site, and then the dose is adjusted depending on the individual response of the patient. Most patients need to be re-treated every three months, and gradually higher doses may be needed over an extended period of time.
Side effects of botulinum toxin include lagophthalmos, ectropion, or volvulus.Side effects such as watery eyes, dry eyes, and sometimes keratitis have also been reported. Accidental ingestion of a toxin into the orbit can lead to ptosis ± diplopia. All these side effects (as well as medical ones) disappear within 3-4 months.
Surgical treatment
In severe blepharospasm and resistance to pharmacological treatments, selective myomectomy can be used (dissection of some of the muscles covering the eyes is performed).