![]() So why was the human eye not as reflective as the eyes of animals? Simply because the rays of light that were supposed to hit a person’s eyes were often blocked by the head of the observer. Further examination proved that this illumination was due, in fact, to a reflective layer behind the retina, a structure that also existed in human eyes. More than two centuries ago, observers believed in something called the “Black Pupil” phenomenon, wherein eyes of animals appeared to look bright or luminous when they were excited–something that was not observed among humans. Diabetic retinopathy, a condition experienced by people with diabetes wherein high blood sugar levels cause damage to blood vessels in the retina, could be diagnosed early with the recognition of lesions during ophthalmoscopy. In patients with severe hypertension, retinal hemorrhages found during fundoscopy signify categorization to accelerated hypertension. Optic disc edema, the swelling of the optic disc due to an increase in fluid, is another ophthalmoscopic condition with serious underlying causes such as increased intracranial pressure or papilledema, infarction, inflammation, or infiltration of cells suggestive of cancer. For instance, pathological optic cupping, which is signified by an abnormally large optic cup-to-disc ratio, could be suggestive of glaucoma, an elevated intraocular pressure that can lead to loss of vision or irreversible blindness. ![]() The inspection of these regions can provide significant clues on the probable cause of a simple headache or symptoms of some serious vascular condition. Ophthalmoscopes, the primary tools for this procedure, have, therefore, earned their spot as standard instruments in the doctor’s arsenal, not just for ophthalmologists only. These illnesses typically cause secondary changes in the retina, and their progression can be examined through a quick, 5 to 10-minute check-up of the fundus of the eye. ![]() These observations come in handy for the medical diagnosis of common medical conditions such as diabetes, hypertension, vascular disease, and lipid disorders. Fundoscopy is a painless technique that allows the observer to gather a visualization of the patient’s retina. Balances, Scales and Weighing EquipmentĪs an Amazon Associate Conductscience Inc earns revenue from qualifying purchasesĪn integral component of every doctor’s routine physical assessment is an inspection of the eye, a procedure called fundoscopic examination.Also, fibrinoid necrosis of choroidal arterioles occurs leading to segmental infarction of choriocapillaries. Severe intracranial hypertension leads to optic nerve ischemia and edema (papilledema). In this stage, retinal signs occur such as retinal hemorrhage (flame-shaped and dot blot), hard exudate formation, necrosis of smooth muscle cells and retinal ischemia (cotton-wool spots). Seen in patients with severely increased BP characterized by the disruption of the blood-brain barrier and leakage of blood and plasma into the vessel wall disrupting the autoregulatory mechanisms. The vein, in turn, appears dilated and torturous distal to the AV crossing. AV crossing changes occur when a thickened arteriole crosses over a venule and subsequently compresses it as the vessels share a common adventitious sheath. This leads to a severe form of arteriolar narrowing, arteriovenous (AV) crossing changes, and widening and accentuation of light reflex (silver and copper wiring). It was observed that plasma leptin levels were higher in patients with hypertensive retinopathy and postulated that it is associated with vascular endothelium damage. Renal dysfunction (persistent microalbuminuria and low creatinine clearance) in patients has shown to be a marker for hypertensive retinopathy and end-organ damage. Smoking is considered to have a strong association with severe or malignant hypertensive retinopathy as studied by Poulter et al. studied the genetic factors linked to hypertensive retinopathy and found the deletion of the allele of the angiotensin-converting enzyme has a higher risk associated with the development of hypertensive retinopathy. Genetic factors can also play a role with certain genotypes associated with an increased risk of hypertensive retinopathy. The prevalence of hypertensive retinopathy is more in Afro-Caribbean as compared to Europeans and more in women as compared to men. Apart from essential and secondary hypertension, there are other factors which play an important role in the development of hypertensive retinopathy.
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