Evaluating the Postoperative Results of Endoscopic Third Ventriculostomy in Triventricular Hydrocephalus by Correlation of Clinical Outcome and Magnetic Resonance Dynamic Cerebrospinal Fluid (CSF) Flowmetry

Background: Endoscopic third ventriculostomy is surgical procedure that is operated for management of obstructive hydrocephalus and regained popularity with large number of promising results. Aim: To evaluate the outcome of Endoscopic Third Ventriculostomy by correlation between clinical outcome and MRI cerebrospinal fluid flowmetry postoperatively. Patients and Methods: This study was conducted in Department of Neurosurgery at Tanta University from January 2018 to January 2020. It included 25 patients with triventricular hydrocephalus with different etiologies. All patients were subjected to history taking, complete physical, neurological examination, routine preoperative laboratory investigations, radiological investigations e.g. non contrast CT and MRI of the brain. Patients underwent surgery according to the exact cause of hydrocephalus, which was known and identified by neuroimaging and endoscopic third ventriculostomy. Outcome assessment was done by neurological evaluation for resolution of their clinical symptoms and a shunt free stable clinical status. Patients were evaluated once weekly for the first month then monthly for the first 3 months and the patients were finally evaluated at the end of the 6th month postoperatively. Results: Of  25 patients,  9 patients (36%) with Aqueduct stenosis, 1 patient (4%) with Brain stem glioma, 1patient (4%) with Brain stem tumor, 5 patients (20%) with PF tumor, 6 patients (24%) with Pineal tumor, 1patient (4%) with Thalamic glioma, 1patient (4%) with Tectal glioma and 1only one patient (4%) with Chiari 1 malformation.92% had Patent ETV stoma with adequate flow: OFA value >75 μL, 8% had Patent ETV stoma with low flow: OFA value from 25 up to <75 μL. The mean Headache VAS Preoperative was 6.08 (±1.04 SD). the baseline mean Evan's Ventricular ratio was 0.34 ± 0.02 and 60% of cases had papilledema. Blurring of vision was present in 60% of cases, headache in 100% of cases and vomiting was present in 60% of cases. Conclusions: Dynamic MRI of CSF flow provides reliable and immediate information on the efficacy of ETV, in addition to the flow-void presence at the level of the 3rd ventricle floor fenestration in both midsagittal and perpendicular plane, even in the absence of phase-contrast techniques which is significantly correlated with clinical signs and symptoms improvement in the patients.