Objective: The aim of this prospective study was to analyze the changes in cerebrospinal fluid (CSF) distribution after endoscopic third ventriculocisternostomy (ETV).
Methods: Twenty-two hydrocephalic children (eight boys, aged 3 months to 17 years) candidates for ETV were studied by preoperative brain magnetic resonance (MR) and repeated post-ETV MRs at established time intervals. A volumetric analysis of CSF distribution after ETV was performed using a specific software.
Results: Fifteen children had an uneventful follow-up, whereas four required a second ETV due to a secondary closure of the stoma, one died of acute intracranial hypertension, and two needed an extrathecal shunt. A progressive reduction in the volume of the ventricles was found in case of successful ETV during the follow-up period. The ventricular volumes were reduced in average of 76 % of the initial volume at day 3, 69 % at 2 weeks, 42 % at 2 months, and 40 % at 6 months. This finding was associated with an enlargement of subarachnoid spaces which increased in case of successful ETV (192 % of initial volume at day 3; 210 % at day 15; 428 % at 2 months; and 468 % at 6 months). In case of secondary closure of the stoma, the distribution of intra- and extraventricular CSF tended to go back to the preoperative status.
Conclusion: Volume variations of the ventricles and the subarachnoid spaces are a good indicator of the efficacy of the ETV.