Intraoperative ventriculo-stomographic evaluation of endoscopic cerebrospinal fluid diversion and flow restoration procedures

Abstract

Purpose. This prospective study was designed for intra-operative demonstration of cerebrospinal fluid (CSF) flow in ventricles and cisternal spaces before and after neuroendoscopic procedure. The aim of this study was to evaluate site of obstruction of CSF flow and subsequent stomal or aqueductal patency after endoscopic third ventriculostomy (ETV) or aqueductoplasty in patients with hydrocephalus of diverse aetiology.

Method. Seventeen patients with hydrocephalus due to diverse aetiology underwent ETV (n = 15) and aqueductoplasty (n = 2) or cysto-ventrticulostomy (n = 1) or transaqueductal removal of neurocysticercus cyst (NCC) (n = 1). Intra-operatively, radio-opaque contrast agent (iohexol) instillation into the third ventricle was used for qualitative evaluation of obstruction and post-procedure CSF flow across the stoma into cisternal spaces.

Result: 11 male and 6 female patients ranging from 3 to 50 years of age were included in the study. Post-procedure intra-operative ventriculo-stomography (IOVSG) showed free flow of dye across the endoscopic stoma (n = 13) or aqueduct (n = 2) into cisternal spaces. Diagnosis of fourth ventricular NCC was made in one patient with panventriculomegaly. In two patients of tuberculous meningitis hydrocephalus, poor flow of contrast in the prepontine area and basal cisterns was seen on IOVSG. They were subjected to ventriculoperitoneal shunt insertion in the same sitting. Cine MRI confirmed the patency of stoma or aqueduct in follow-up period in all patients with successful endoscopic procedure.

Conclusion. IOVSG is a simple and safe technique that helps in confirming the adequacy of endoscopic procedure during surgery and thereby facilitates intra-operative decision about further management.

Key words:

• Aqueductoplasty
• ETV
• neuroendoscopy
• stomography
• ventriculography

Acknowledgements

Dr. Manu, Dr. Deepak, Dr. B. K. Ojha and Dr. Anil were part of neurosurgical team. In addition, Dr. Manu and Dr. Deepak helped in preparation of manuscript. Dr. Rakesh interpreted the radiological images. Dr. Mazhar Husain headed the neurosurgical team and supervised the research work.