The University of California, San Diego, has just developed a smartphone application capable of detecting, instantly and easily, the early signs of various neurological disorders, including Alzheimer’s disease. How ? Via the phone’s camera, which can track changes in a person’s pupil size with a resolution of less than a millimeter. Analysis of these measures can then be used to assess his cognitive state.
The idea is not new and as technologies evolve, the eyes will always prove to be more relevant for diagnosing a wide variety of diseases. Indeed, because of their partial transparency, they require much less invasive methods of examination than other parts of the body.
Without any technology, just by looking yourself (or your loved ones) in the eye, you can spot some benign health problems on your own — but not alone. Here are the concrete examples of some characteristics that you can analyze.
Pupil dilation abnormality
The pupil, this “black hole” in the heart of our eye, reacts immediately to light thanks to the iris (colored part, made up of muscle fibers) which can contract or expand like a camera diaphragm.
It adapts by getting smaller in bright environments and larger in dark environments. This pupillary reflex (or photomotor reflex) is often monitored by health professionals.
A slow or delayed pupil size response can be a sign of several diseases, including serious illnesses such as Alzheimer’s disease, as well as the effect of medications and drug use. Dilated pupils are common in people who use stimulants, such as cocaine and amphetamines. Very small pupils can be seen in heroin users.
Color of the “white of the eye”
A change in color of the sclera (the “white of the eyes”) indicates that something is wrong…
For example, a red, bloodshot eye can be caused by alcohol or drug abuse. It can also be caused by irritation or infection, which in most cases clears up within a few days.
If the color change persists, it could indicate a more serious infection, inflammation, or a reaction to contact lenses or their solutions. In extreme cases, a red eye indicates glaucoma, a condition that can lead to blindness.
Sclera turning yellow is the most obvious sign of jaundice (jaundice) or other liver damage. The underlying causes vary widely and this yellowing of the skin and eye is due to an excess of bilirubin (yellow pigment) in the blood when it can no longer be excreted normally by the liver. They include inflammation of this organ (hepatitis), genetic or autoimmune diseases, as well as certain drugs, viruses, or tumors.
A small red spot in the white of the eye, witnessing a subconjunctival hemorrhage – or a small blood vessel that has locally ‘popped’ – can be frightening. Usually there is no cause for alarm: the causes of this phenomenon are rarely obvious and the bleeding generally disappears within a few days.
However, it can also be an indication of high blood pressure, diabetes, and blood clotting disorders that cause excessive bleeding. Blood-thinning drugs like aspirin can also cause it. Also, if this problem is common, it may indicate that you need to limit your intake of these drugs, or at least revise the dosage.
Appearance of a bright arc
It is a common feature after a certain age, hence the scientific name arcus senilis (or senile arch of the cornea, gerontoxon): a paler “arch”, sometimes almost white, can form at the periphery of the cornea.
It’s due to a deposit of cholesterol… but it’s not necessarily the sign of hypercholesterolaemia, and it doesn’t reduce visual acuity. In some cases, however, it may actually be associated with high cholesterol and an increased risk of heart disease. It can also reveal alcoholism.
Development of a small fat bulge
Sometimes the most disturbing features that can appear on the eyes are actually the most benign and easily treated.
A small yellowish cystic bump may appear on the white of the eye: this is a pinguecula, a buildup of fat and protein. This small lesion (which may be caused by exposure to dust, etc.) may be accompanied by mild inflammation and irritation. It does not cause visual discomfort and does not necessarily require treatment. But if the inflammation does occur, it can be easily cured with eye drops or removed with minor surgery.
The pterygium (or pterygia) also comes at the level of the sclera, but the impact is not the same. This time it is a developing pink growth covering the whites of the eyes; it’s not a vision hazard until it starts to affect the cornea.
Fortunately, its development is very slow. And like the pinguecula, it can be easily removed. In fact, it must be removed long before it reaches the cornea. If left in place, the pterygium forms an opaque “film” on the cornea that obscures vision. One of the main factors causing the pterygium (as with the pinguecula) is said to be chronic exposure to ultraviolet rays from the sun.
Eyes that bulge out more
It is a feature of the face: the eyes can be more or less sunken, set apart… Some people have more bulging eyes than others. But sometimes this feature evolves and there is a tendency of the eyes to project forward (we speak of exophthalmos). The eye appears to be “growing”, mainly due to an increase in the eye muscles; if the phenomenon is accentuated, then visual discomfort is possible, with pain, poor hydration of the world, etc.
The cause may be medical and require special attention. It can be the result of an infection (the most common cause in children), an injury, an inflammation (linked to a fungal infection, an abscess, etc.), a tumor behind the eye (very rare), etc. But the most The most common cause is a problem with the thyroid gland (80% of these thyroid cases are due to hyperthyroidism), which causes inflammation of the eye tissues and causes them to swell. She then touches both eyes.
What the eyelids say
The eyelids can also indicate many diseases. These are usually related to minor disorders of the glands associated with them.
For example, a stye is a common and minor bacterial infection of the base of the eyelashes, causing swelling and localized redness. It usually goes away on its own or with warm compresses; in case of persistence it can be removed by a simple procedure. The chalazion, which appears as a red bump on the upper lid and, more rarely, on the lower lid, is due to an obstruction of a sebaceous gland.
Spasms and involuntary twitching of the eyelid (myokymia) will irritate, irritate, but in most cases the phenomenon is completely harmless and unpleasant rather than dangerous. It may be associated with stress, a nutritional imbalance or excessive caffeine consumption.