Cerebrovascular compression in a canine model of obstructive hydrocephalus

Because of observed cerebral blood flow changes in hydroceplialus, we hypothesised that there is a preferential compression of the cerebral vessels accompanying chronic tissue compression. In this preliminary study we quantitated 12 animals that underwent successful surgical induction of hydrocephalus via cyanoacrylic glue injection into the IVth ventricle. We investigated the degree and pattern of vascular compression by measuring the vessel density, diameter, and area percent in three serial sections from multiple regions m the parieto-occipital lobe. These parameters were related to the degree of tissue compression, as measured by post-induction .MR1. An overall increase in blood vessel area was observed in periventricular white matter (PW) (p = 0.036) and in superficial grey matter (p = 0.020). Vessel diameters were increased overall (p <0.001) and in PW (p = 0.001). An overall increase in large blood vessel density (p = 0.001) was also observed. These findings suggest the cerebrovascular tree is not compressed in chronic hydrocephalus, and in fact is spared relative to the surrounding parenchyma.