Endoscopic treatment of patients with idiopathic hydrocephalus with extraventricular cisternal obstruction of the cerebrospinal tract

Abstract

The possibility of developing extraventricular CSF pathways obstruction was demonstrated in the mid-20th century. The development of neuroimaging (mainly MRI) and endoscopic techniques made it possible to plan and perform minimally invasive surgeries in a narrow anatomical corridor and achieve the regression of neurological symptoms. Purpose of the study: to determine the effectiveness of endoscopic surgery for hydrocephalus due to idiopathic extraventricular CSF pathways obstruction. Materials and methods. Sixty-five patients with signs of extraventricular obstruction underwent examination and surgical treatment at the Center of Neurosurgery from 2007 to 2020. The preoperative Kiefer Scale score was 6.8±3.3 (0-15) points, and the Rankin Scale score — 2.2±1 (0-5) points. Endoscopic third ventriculocisternostomy was performed as the first operation in 42 (64.6 %) patients. Ventriculoperitoneal shunting was performed in 17 (26.1 %) patients. Six (9.2 %) patients were not operated on. Results. After endoscopic surgery, the condition of the patients significantly improved (p < 0.001) after 2 and 12 months. Complete or partial regression of symptoms was noted in 85 % of the patients 1 year after surgery. After shunt surgery, the trend was comparable. The only radiological parameter that changes and correlates with the patients’ condition is the position of the premammillary membrane and the flow void. The remaining indicators of the CSF system of the brain did not actually change. In all cases of the endoscopic surgery, an additional membrane conglomerate that corresponded to preoperative tomograms was found under the premammillary membrane. Conclusion. The high efficiency of endoscopic third ventriculocisternostomy allows recommending this technique as the primary one in patients with extraventricular CSF pathways obstruction, with the exception of cases of anatomy abnormalities of the third ventricular fundus area (short premammillary membrane in combination with a high-lying basilar bifurcation) and cisterns of the posterior cranial fossa base (narrow cisterns, whose dimensions do not allow inserting an endoscope under the premamillary membrane).