HYPERTENSION AND ITS EFFECTS ON THE EYE - 3

HYPERTENSION AND ITS EFFECTS ON THE EYE - 3

High blood pressure has significant negative effects on certain organs and systems. It can cause serious damage to organs and systems, especially the eyes, heart, kidneys and central nervous system.

Effects of Hypertension on the Eyes:

The scientific name is "Hypertensive Retinopathy". In this disease, high blood pressure refers to situations in which it has negative effects on the visual membrane of the eye.

Hypertension affects the retina (the network layer or layer consisting of neural tissues), which is located inside and behind the eye and creates the visual function and transmits image stimuli to the brain. It is a vascular disease that causes damage due to hypertension and arteriosclerosis.

Due to high blood pressure, narrowing and bleeding may occur in the arteries in the retina of the eye. In severe cases, edema may develop at the head (papilla) of the optic nerve. These changes in the eye can cause visual impairment and even blindness.

Retinal vessels could not be examined until von Helmholtz invented the ophthalmoscope in 1851. The most respected Ophthalmologist in this field is Marcus Gunn, whose observations about sclerotic changes in the retinal vessels and the relationships of vascular changes in the retina, central nervous system and excretory system are still considered classic. It causes general and local narrowing of the branches.

Ophthalmoscopic Images in Hypertensive Retinopathy

Wall, reflection and crossover changes occur in the vessels. If high pressure continues for a long time, plasma and red blood cells leak out of the vessel as a result of the collapse of the internal "blood-retina barrier". In examination of the retina with an ophthalmoscope, retinal hemorrhages, exudates resulting from extravascular leakage (a group of cellular bodies caused by degenerative changes of nerve fiber axons in the inner layers of the retina), intraretinal lipid (oily substance) accumulation, macular star-shaped settlement of fatty substances in severe hypertension and retinal vascular terminals are detected. -Clogging of the branchlets may be observed.

Retinal hemorrhages are mostly in the form of a candle flame that fits into the superficial nerve fiber layer. Closely located round and m� Hemorrhages in the form of ink spots and the presence of yellow-white intraretinal fatty substances accompanying them indicate the severity of hypertension.

Although, as a rule, arteriosclerotic changes are due to thickening of the vascular wall, hypertension is thought to be mainly due to vascular spasm. Since hypertension has a very important effect on the development of arteriosclerotic changes, it is not possible to consider them completely separately.

The severity of arteriosclerosis is more related to the height of diastolic pressure. Characteristic changes in the retinal vessels are generally distributed uniformly in all body artery branches, and the ophthalmoscopic appearance almost reflects the state of the general circulation. For this reason, internal medicine specialists request consultation from an ophthalmologist in this disease and diabetic retinopathy.

Common arterial narrowing is a typical symptom of hypertensive retinopathy. Although it is seen as an acute vascular spasm response in acute hypertension, it is more frequently seen in chronic hypertension. This decrease in vessel diameter causes a decrease in the retinal artery diameter / vein diameter ratio in hypertension. Normally this ratio is 2/3. The evaluation is made by comparing it to the normal ratio or the average vessel diameter of a person of the same age with normal blood pressure. Regional arterial stenosis is due to spasm of the vessel wall in one area and may be reversible. Its rating reflects the severity of the spasm. Diameter changes near the optic nerve head may be physiological.

Light reflection from vessels:

The increase in thickness of the vessel wall causes a progressive change in the reflection of light. Normally, the vessel wall cannot be seen, only the column of red blood cells in the lumen can be seen as a red line, which we accept as a vessel. The reflection of light entering from the convex surface of the vessel wall causes a second light line to appear in the middle of the blood column, which is normal light reflection. As the wall thickens, the brightness of light reflection disappears and it becomes more rough, dull and scattered, which is the earliest symptom of arteriolosclerosis.

Vascular diameter (calibration, lumen) change light:

In addition to the increase in wall thickness in the arterial branches and the narrowing of its lumen, the diffusion of light gives the vessel a reddish-brown 'copper wire' appearance. With good control of hypertension, this finding decreases relatively. If the arteriolosclerotic process continues, the thickening of the wall continues along with the narrowing of the lumen, resulting in a 'silver wire' appearance where the blood column cannot be seen as a thin line. During this period, the vessels do not seem to be able to carry blood, but fluorescein angiographic examination reveals that perfusion mostly continues. This is an uncommon finding in controlled hypertension.

Arterial/vein crossing changes:

Retinal arteries and veins usually share a common junction at the point of crossing where the vein extends forward. They go into an outer sheath. Changes in the vein wall create a 'notch' in this area, which causes pressure on the vein and narrowing of the lumen, and may also cause the vein to change direction. This condition can range from slight thinning of the blood column to severe thinning and cessation of the visible blood column. Crossover changes are characteristic of chronic hypertensive disease.

Retinal Aneurysms:

Microaneurysms, that is, enlargements in the terminal branchlets, are a finding that is seen in a wide range of vascular diseases and is not specific to hypertension. They form as bubbles localized in weak areas of the wall.


NEGATIVE FACTORS FOR HYPERTENSION DISEASE

  • Hypertension starts at a young age,

  • Male gender,

  • Diastolic pressure is constantly 115 mm. Hg (mercury) being above

  • Enlarged heart

  • Heart failure has developed

  • Ischemic disorders in the heart

  • Impaired kidney functions

  • Cerebral vessel and brain disorders

  • Vascular disorders in the retina of the eye

  • Edema in the optic disc (papilla) of the eye (papilledema)

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