Valsalva retinopathy results from a sudden increase in intraocular venous pressure due to forced exhalation against a closed glottis. This leads to rupture of superficial capillaries in predisposed individuals.
Preretinal hemorrhage accumulates in the sub-internal limiting membrane space, typically overlying the macula (Fig. 19.3.1). With rest, the red blood cells layer such that there is a serous component superiorly.