Final answer:
AV nicking occurs when arterioles compress adjoining veins in the retina of the eye, often associated with hypertension. It is visible during eye examinations and signifies changes in vascular health.
Step-by-step explanation:
AV nicking is a condition where arterioles press on veins of the eyes, leading to a noticeable narrowing or indentation on the veins at the points where they are crossed by arterioles. This finding is often observed through an ophthalmoscope during a fundoscopic exam of the retina and can be an indicator of hypertension or other vascular conditions.
Arterioles, being smaller blood vessels with thicker muscular walls, can exert pressure over the adjacent veins, especially when there's increased stiffness or blood pressure. This compromises the venous return and can lead to changes in the eye's vascular structure. Conditions such as hypertension can increase the risk of AV nicking due to the increased arterial pressure that is exerted on the veins, causing compression and resulting in the appearance of nicking.