222. Duration of Cerebrospinal Fluid Diversion after Functional Hemispherotomy Results in Decreased Rates of Hydrocephalus

Authors: Kathleen Elizabeth Knudson, MD; Gewalin Aungaroon, MD; Ravindra Arya, MD; Katherine Holland-Bouley, MD, PhD; Jeffrey Tenney, MD, PhD; Anna Byars, PhD; Hans Greiner, MD; James Leach, MD; Francesco Mangano, DO (Greenville, NC)


Functional Hemispherotomy (FnH) surgery is a well-established technique to treat medically refractory epilepsy. It is associated with a highly variable risk for development of hydrocephalus. We reviewed our surgical outcomes and assessed any possible risk factors for the development of hydrocephalus requiring cerebrospinal fluid (CSF) diversion.  


We reviewed all FnH surgeries done at our institution from 2006 to 2019. We included 73 patients in this study with an average follow up of 4.43 years. Seizure outcomes were determined using the ILAE scale. Indications, etiology, pathology, and neuropsychological evaluation as well as complications were recorded. Complications included need for further surgery, medical complications, and rates of hydrocephalus. We analyzed patients who required a shunt for possible risk factors.


Overall surgical outcomes showed 52/73 (71.2%) patients were an ILAE score 1. Nine patients required additional surgery. This was seen from 2008-2011, indicating potentially the presence of a learning curve to the procedure. A total of five patients (6.8%) required shunt placement postoperatively. We found that shunt placement was associated with shorter duration of external ventricular drain (EVD), compared to those who did not require a shunt.


Our data report good seizure outcomes with FnH. Additionally, we found that duration EVD was a risk factor for the development of hydrocephalus after FnH. Changes in technique, including longer post-operative CSF diversion, resulted in a decreased risk for the development of hydrocephalus requiring shunt placement.