Influence of the State of the Subarachnoid Space of the Cranial Base in Hydrocephalus Resolution after Endoscopy.

Objective To compare the resolution rate of hydrocephalus after endoscopy (predominantly endoscopic third ventriculostomy [ETV]) using flexible endoscopes during a 5-year period in patients with a permeable and a nonpermeable subarachnoid space (SAS). Material and Methods We conducted a retrospective cohort study of the videos and records of 150 hydrocephalic patients chosen randomly who underwent ETV (and other endoscopic procedures) with a flexible endoscope. The patients were classified into two groups based on the neuroendoscopic findings. The first group included patients with a permeable SAS, and the second group included patients with a nonpermeable SAS. A normal SAS or one with slight arachnoiditis was considered permeable. Adhesive arachnoiditis and immature or mechanically obliterated SASs were considered nonpermeable. Results We found a success rate of 70% in patients with a permeable SAS versus 33% in patients with a nonpermeable SAS. The baseline characteristics of both groups were homogeneous. We obtained a statistically significant difference (p < 0.0001) with hazard ratio (HR) 3.42 (95% confidence interval [CI], 1.88-6.22). Another important factor involved was age that showed a statistically significant difference (p < 0.0018) with HR 3.28 (95% CI, 1.55-6.93). Conclusion The permeability of the SAS is an important prognostic factor in the resolution rate of hydrocephalus after ETV (and other endoscopic procedures) using flexible neuroendoscopes. Therefore we recommend that the characteristics of the SAS be examined following every endoscopic procedure for hydrocephalus to identify patients at risk of recurrence.

Endoscopic transventricular exploration with biopsy of the basal cisterns and the role of endoscopic third ventriculostomy in patients suffering with basal cistern meningitis and consecutive hydrocephalus.

OBJECTIVES: The purpose of this work is to elucidate the efficacy of endoscopic basal cisterns exploration, biopsy, and third ventriculostomy (ETV) in patients with basal cistern meningitis and arachnoiditis. MATERIALS AND METHODS: The cases and videos of all patients in whom flexible neuroendoscopy was performed during the period of January 2005-June 2012 at the University Hospital 'Dr. Ignacio Morones Prieto' in San Luis Potosí, México. A group of 47 patients with radiological diagnosis of basal meningitis, arachnoiditis, and negative cerebrospinal fluid analysis were included. RESULTS: From the 28 (60%) patients with histological diagnosis, 22 (47%) were made from biopsy from the arachnoid membranes of the basal cisterns only, 4 (9%) only from the cerebral cortex, and 2 (4%) from both sites. There were no complications related to the endoscopic procedure. In 23 patients from the 42 with hydrocephalus, ETV was successful. The grade of diagnostic accuracy of both biopsies in detect etiology was 68% (28 of 47 patients), the diagnostic accuracy of arachnoid biopsy was 60%, and diagnostic accuracy of convexity brain biopsy was 21% with 24 and 6 patients, respectively. DISCUSSION: Endoscopic transventricular biopsy of the basal cisterns seems to be a safe and a relatively accurate procedure. As longs as frozen subarachnoid space was not seen, the possibilities of performing ETV in hydrocephalus condition are elevated depending on the causal micro-organism.