Fig. 4
From: Endoscopy-assisted purely total outer wall excision for pediatric Sylvian arachnoid cysts
Change of cystic pressure before and after operation. A The preoperative pressure from low to high is in the subdural space (blue area), parenchyma (orange area), and cyst (red area), respectively. Red-high pressure area, orange-medium pressure area, blue-low pressure area. B After communicating the cyst cavity with broad subdural space, the residual cyst cavity transformed to a low-pressure area equal to subdural space (blue area)