Endoscopic Third Ventriculostomy and Cortical Biopsy in Patients With Normal Pressure Hydrocephalus

Introduction Normal pressure hydrocephalus (NPH) has conventionally been treated by placement of a ventriculoperitoneal shunt. However, it can also be treated with a less invasive technique, an endoscopic third ventriculostomy (ETV). Unfortunately, there is a lack of evidence on the characteristics of NPH patients who are most likely to benefit from ETV. This study seeks to identify if patients at risk of dementia with NPH should be candidates for an ETV. Methodology Thirty-six NPH patients who underwent ETV at two institutions between July 2007 and December 2014 were pre-surgically assessed for various risk factors. At the time of ETV, a cortical biopsy was obtained and assessed for plaques consistent with dementia. Post-procedure, patients were followed and assessed for symptoms such as gait improvement, headache, memory problems, incontinence, and dementia. ETV success was defined as an improvement in gait. Results The mean age of patients with successful ETVs was 65.8 ± 6.0 versus 74.5 ± 7.0 for failed ETVs. Sixty-seven percent of patients with negative biopsies showed gait improvement by the final follow-up appointment as compared to only 33% of patients with positive biopsies (p>0.05). Younger age was correlated with successful ETV (p=.003). Memory disturbance (p<0.05) and incontinence (p<0.05) after surgery were both associated with a lack of gait improvement at the final follow-up. Conclusion Biopsy was not a significant predictor of ETV success; however, there was a correlation between younger age and ETV success. Additional studies are required to determine if there is a relationship between cortical biopsy findings and ETV success.