Postoperative evaluation of third ventriculostomy patients using 111in-DTPA.

A radioisotope scanning and clearance procedure has been developed for the postoperative assessment of third ventriculostomy patients. The patency of third ventriculostomy sites can be verified by this procedure, and the bulk flow clearance of CSF can be quantitated. 4 postoperstive third ventriculostomy patients have been evaluated by this procedure to date. In each case the third ventriculostomy site was shown to be patent. The bulk flow clearance of CSF ranged from 170 to 342 cm3/24 h. Comparison of these figures with estimates of CSF production suggests that the majority of CSF reabsorption in these patients occurs through the arachnoid villi.