Melissa, a 30-year-old educator, came to the emergency department with a sudden onset of double vision. She had not been in an accident or suffered any trauma and had never experienced this symptom before. However, she noted that a few months earlier, the vision in one of her eyes had become blurred and then returned to normal shortly after. She told herself it was a sign of fatigue after a period of intense work on a screen.
After some basic optometric tests, then more advanced tests of visual perception, the visual episodes were thought to be related to multiple sclerosis. Melissa was then referred to a neuro-ophthalmology specialist who confirmed the diagnosis, and she was quickly treated.
Is Melissa’s case unique? Over my 30 years working as an optometrist, I’ve seen many patients with different vision and eye health problems, the cause of which turned out to be an illness they didn’t know they had.
As a professor at the School of Optometry at the Université de Montréal, I teach students that certain ocular symptoms can be linked to general health problems. Optometrists are trained to identify the various diseases that can manifest themselves through the eyes and to work with other health professionals to manage them.
Diabetes
Because diabetes will affect almost 8% of the population by 2030, screening is a crucial issue. However, it is estimated that diabetes is not generally diagnosed until six to 13 years after its onset. An eye health examination can shorten this delay since it is often possible to identify characteristic lesions of the disease at the back of the eye before other symptoms of diabetes appear.
Early diagnosis is crucial since within five years of diagnosis (i.e., 11 to 15 years after the onset of diabetes), 25% of patients with Type 1 (juvenile diabetes) and 40% of those with Type 2 (adult diabetes) who are treated with insulin will develop eye lesions that can have a major effect on their vision. Early identification and rigorous monitoring of eye health significantly reduces the risk of blindness, which can happen when the disease is not treated.
Unmasking the silent killer
If diabetes affects a significant number of patients without them knowing it, what can be said about high blood pressure and high cholesterol? These two conditions significantly increase the risk of coronary heart disease or stroke in our societies.
The eye is the only place in the human body where blood vessels can be seen without having to make an incision or use invasive techniques.
- High blood pressure (known as the silent killer) can be seen by crushing of vessels and very specific signs on the retina.
- Hypercholesterolemia creates cholesterol deposits inside the vessels.
- Atherosclerosis is associated with Hollenhorst plaques, also visible inside the vessels.
- Cholesterol can also be seen in the cornea (lipid arc) or in the adnexa (xanthelasma).
In all these cases, very often the symptoms experienced by the patient are so few, or progress so slowly, that he or she considers them almost normal.
Normotensive or open-angle glaucoma
The absence of symptoms is also the norm for glaucoma. This pathology of the optic nerve is usually associated with excessive production of aqueous humor in the eye or a deficit in its evacuation.
The pressure inside the eye then increases and through different mechanisms leads to the loss of nerve fibers in the nerve. The visual field narrows very slowly (and therefore can go unnoticed), so the person ends up with tunnel vision after several years.
By the time this loss of vision affects them, it is often late, so the damage to the optic nerve can be very extensive. This damage is mainly ocular, although it can also be induced by the effect of certain drugs (such as cortisone).
Normotensive glaucoma is of a completely different nature. In this case, the pressure inside the eye remains normal but the nerve is still damaged. The mechanisms at play are different from those in chronic open-angle glaucoma.
Normotensive glaucoma is often associated with low blood pressure or conditions such as sleep apnea. If it is present, the patient must be referred to a family doctor for a thorough investigation.
The disease of the century
Because cancer is becoming so widespread and is expressed in so many ways, we call it the disease of the century. Cancers that affect the eye (retinoblastoma) can also cause metastases to the lungs and liver.
Here again, the disease often develops without symptoms until it is too late. So early detection is crucial, because the patient’s very survival is at stake.
Other types of asymptomatic retinal pigment (shaped like a bear’s paw) may be associated with cancer of the colon, which has a very negative prognosis if management is delayed.
A simple visual field measurement may reveal abnormalities that some patients are unaware of, or that they consider so benign they don’t bother to report them. However, many visual field abnormalities hide brain tumors, such as pituitary adenoma, or nerve fibers compressed by blood vessels.
Abnormal eye movements, asymmetric pupillary responses, sudden reading problems or the appearance of diplopia are all yellow flags that require further ocular and neurological investigation.
Rather than the mirror of the soul, the eyes become an open window on our overall health. That makes regular consultations with an optometrist more important than ever, even when there are no symptoms. Many disorders can be detected and treated to either minimize illnesses or prevent them altogether.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
News
Nanodiscs: What Are They and How Are They Shaping the Future of Medicine?
Nanodiscs are synthetic phospholipid particles with a distinct morphology and size that enhance their efficiency in drug delivery applications.1 First developed by Sligar et al. in the early 2000s, these model membrane systems measure around 10 [...]
New Discovery Reveals How Ovarian Cancer Starves Immune Cells
Researchers discovered that ovarian tumors hinder T cells’ energy supply by trapping a key protein, blocking lipid uptake. A new approach to reprogram T cells could enhance immunotherapy for aggressive cancers. Researchers at Weill Cornell [...]
Innovative Drug-Design Strategies to Overcome Antibacterial Resistance
Antibacterial resistance occurs when antibiotics fail to treat bacterial infections. This incidence is considered one of the top global health threats, stemming from the misuse or overuse of antibiotics in humans and animals.1 The [...]
Team introduces a cost-effective method to redesign search engines for AI
The internet search engine of the future will be powered by artificial intelligence. One can already choose from a host of AI-powered or AI-enhanced search engines—though their reliability often still leaves much to be [...]
Experiments demonstrate precise delivery of nanoparticles to lung
In recent years, bio-medical engineers have been developing promising techniques that could help diagnose diseases or precisely target specific regions inside the human body. Among these promising therapeutic strategies are methods that rely on [...]
What is Lassa fever? Everything to know about Ebola-like virus
Lassa fever has reached the US for the first time in a decade, in a case that has surprised health officials. The middle-aged patient in Iowa, who was not identified, died a 'short time' after being hospitalized [...]
Harvard Study Links Popular Plastic Ingredient to DNA Damage
Phthalate affects egg formation in C. elegans, resulting in abnormal chromosome numbers. A recent study conducted on roundworms has discovered that a common plastic ingredient can cause DNA strand breaks, leading to egg cells with an abnormal [...]
New research finds that subtle eye movements optimize vision
Our ability to see starts with the light-sensitive photoreceptor cells in our eyes. A specific region of the retina, termed fovea, is responsible for sharp vision. Here, the color-sensitive cone photoreceptors allow us to [...]
Scientists Were Wrong: Plants Absorb 31% More CO2 Than Previously Thought
New research shows plants absorb 31% more CO2 than previously estimated, raising the global GPP to 157 petagrams per year. Using carbonyl sulfide as a proxy for photosynthesis, this study highlights tropical rainforests’ critical role [...]
Doctors test first mRNA vaccine against norovirus
According to the Robert Koch Institute (RKI), the norovirus, which is widespread worldwide, is the cause of a large proportion of gastrointestinal infections. Those who catch the virus suffer from nausea, diarrhea and vomiting. [...]
Study reveals resistance of Pseudomonas aeruginosa to common cleaning agents
A new study reveals widespread resistance of a major bacterial pathogen to the active ingredients in cleaning agents commonly used in hospitals and homes. The American Chemical Society Infectious Diseases published the research, led [...]
AI’s Next Frontier: System 0 and the Future of Human Thought
“System 0” represents an emerging cognitive tool powered by AI that works alongside human intuition and analysis to enhance cognitive abilities. This new system promises to support complex decision-making and problem-solving but requires careful [...]
The Global Nanomedicine Market: Key Players and Emerging Technologies in Healthcare
This article provides an overview of the global nanomedicine market, highlighting key players, emerging technologies, and the challenges and opportunities that influence its growth and commercialization in the healthcare sector. Nanomedicines are nanotechnology-based drug products [...]
Scientists Have Discovered Toxic “Forever Chemicals” in Bottled Water
Scientists have found toxic PFAS in drinking water samples from around the world, with higher levels in tap water from China compared to the UK. Boiling water or using a filtration jug can reduce [...]
Urban Microbes Are Eating Disinfectants – Are We Fueling a New Health Threat?
New research reveals that microbes in urban environments are evolving to withstand the very cleaning agents designed to eliminate them. The study also uncovers new strains in Hong Kong, previously only found in the [...]
Startling Study Shows High-Potency Cannabis Alters DNA
The study shows that frequent use of high-potency cannabis alters DNA, affecting genes related to energy and immune function. These changes differ between those with and without psychosis, suggesting cannabis use could influence mental health through biological [...]