Predictors of favorable response to the placement of the ventriculoperitoneal shunt in patients with idiopathic normal pressure hydrocephalus (P4.3-071)

Abstract

Objective: Search for clinical factors and complementary studies, in order to determine predictors of a favorable response to the placement of ventriculoperitoneal shunt (VPS) in patients with idiopathic normal pressure hydrocephalus (iNPH).

Background: The indication of VPS is discussed in patients with iNPH, due to the heterogeneity of the response to treatment and the risks involved in neurosurgery.

Design/Methods: Retrospective review of medical records of patients with iNPH treated with VPS assisted in our institution from January 2014 to January 2017. Clinical data and complementary studies were recorded (brain MRI and CT, gait test post-lumbar puncture). Clinical response was evaluated with the Modified Rankin Scale (mRS) at baseline and 12 months of follow-up. A univariate statistical analysis of the variables considered as possible prognostic factors was performed.

Results: 58 patients were included. Among the clinical factors: female presented 3.68 times more chances of improvement after the VPS (p = 0.019), while age, time of evolution of the clinical manifestations and MMSE had no correlation. Regarding the complementary studies: good response to the gait test was associated with better response to the VPS (p = 0.024) and each degree of increase in the angle of the callosum was associated with a 5% reduction in the possibility of improvement, although this effect was not significant (p = 0.08); the Evans index, the presence of Disproportionately Enlarged Subarachnoid space Hydrocephalus (DESH) and the degree of Fazekas had no prognostic correlation.

Conclusions: Female and good response to the gait test could be considered as predictors of a favorable response to the placement of VPS in patients with iNPH. A prospective study is necessary to achieve a homogeneous diagnostic evaluation and a more extensive longitudinal follow-up to evaluate the clinical evolution in this group of patients.