Fig. 2

A Distribution of tissue in holes by ventricular catheter (VC) group. In VCs with Growths, 88% of holes were empty and 11% of holes showed Growths. In VCs with occlusions, 34% of holes were occluded, 10% had non-occluding growths, and 55% were empty. B Bar graphs showing VC categorization within the broad clustering of clinical obstructions versus non-obstructive revisions. Of those VCs that were determined intraoperatively to be obstructed, 23% were designated as ‘Empty VCs’, 13% as ‘VCs with Growths’ and 64% as ‘VCs with Occlusions’. Among VCs that were replaced for causes other than obstruction, 32% were designated as ‘Empty VCs’, 14% as ‘VCs with Growths’ and 54% as ‘VCs with Occlusions’