Chronic Hypertension: Vessel Wall Changes
Retinal vessel wall changes
Moderately sustained hypertension (systolic above 160, diastolic above 100 mm Hg) over at least five years stiffens the wall and narrows the lumen of retinal arterioles. Three changes appear through the ophthalmoscope:
Of the three changes, increased tortuosity is the least reliable because of normal variation. Arteriovenous nicking and an increased light reflex are reliable as signs of chronic hypertension only in patients aged less than 70 years, because advanced age can produce these abnormalities even in a normotensive state.
- : as the stiffened arteriole crosses a retinal vein, it indents the vein and causes slight deviation in its path. This abnormality should be seen in most of the four to six major arteriovenous crossing points within the posterior retina.
- increase in light reflection from vessel wall: the normally flat red color of the arteriole develops a shiny, glistening reflection. In early stages, this change may be difficult to appreciate but as the vessel wall thickens and the blood column narrows, the reflection shifts toward a bronze color ("") and eventually toward gray ("").
- : as the retinal arterioles stiffen, they develop loops.
What to do?
Finding these vascular changes suggests that chronic hypertension is producing end-organ damage and must be better controlled.