Ventricular Failure as a Cause of Unsuccessful Endoscopic Third Ventriculostomy

In spite of extensive studies on cerebrospinal fluid (CSF) dynamics, the mechanism of its circulation is still obscure. The aim of this study is to evaluate the effect of an insult to the brain tissue on the success or failure of an endoscopic procedure. During the period from May 1995 to December 1998 we studied 21 children, ages from 2 to 48 months (mean 15 months) with non-communicating hydrocephalus. The intracranial pressure was measured at the time of endoscopic surgery. The follow-up period was from 2 - 5 years. They were divided into 2 groups. Group I were 8 patients with no history of brain insult. Group II (13 cases) had a previous brain insult (infective and/or vascular). Endoscopic third ventriculostomy (ETV) was done in 17 cases; 5 in Group I and 12 in Group II. Fenestration of cyst/s was done in all of Group I and in 9 cases of Group II. Failure was considered whenever shunt implantation was required. The mean intracranial pressure in Group I was 13.0 mmHg as compared to 9.7 mmHg in Group II (p = 0.015). The failure rate of the endoscopic procedure/s was 25 % and 54 % in Groups I and II, respectively. The success of ETV and/or fenestration of cyst/s depends on a sufficient pressure gradient. The pressure gradient is generated by a normal or compensated ventricular function. Brain tissue damage can result in ventricular failure. The quality of ventricular wall function has a significant role on the success of ETV.