Nonprogrammable Shunts for Communicating Hydrocephalus and Three-Dimensional Volumetry: A Retrospective Analysis

Abstract

Although the use of different types of valves have been extensively studied in shunt surgeries for communicating hydrocephalus (cHC), a consensus about the valve type remains absent. The objective of this study is to evaluate our results with the primary placement of non-programmable valves (NPV) for this indication. We retrospectively analyzed all first NPV implanted between 2014-2020 for cHC. We studied the revision rate, clinical outcome described by modified Ranking Scale (mRS) and radiological evolution using Evans index (EI) and ventricular volumes 3D-semiautomatic segmentation (vv-3DSAS). Forty-one patients were shunted for post-hemorrhagic (61%), post-traumatic (24.4%) and tumoral (14.6%) hydrocephalus (HC). Mean age was 65 years (range 25-89yrs). Overall, 59 procedures were performed including 18 revision surgeries in 12 patients (29.3%). Underlying reason for first shunt revision were valve type related: valve dysfunction, overdrainage, underdrainage and non-valve type related: malpositioning, infection, shunt migration. The shunt-related revision rate was 17.1%. Twenty-eight patients (68.3%) had an mRS improvement of 1 or more points. We found a good correlation between ventricle volumes (VV) and EI and a significant reduction in VV measured by EI and vv-3DSAS was observed. However, the mRS improvement was not correlated with a reduction of ventricle volumes. Overall, our results in terms of shunt revisions as well as clinical and radiological evolution are comparable with the literature for NPV. vv-3DSAS can be used and could be useful to detect small changes in VV in patients with cHC.