Observations on the Activation of Chronic Compensated Hydrocephalus in Adult Patients

Abstract

Objective: There is a broad spectrum of compensated hydrocephalus. Various terms such as long-standing overt ventriculomegaly in adult (LOVA) has been coined, however, even such terms leave diverse aspect of this condition out of account. We have experienced compensated hydrocephalus cases which were considered to be activated after a long time period of quiescent state, and tried to compare their clinical characteristics with the relatively well described entity of LOVA. Methods: We conducted a retrospective review of 206 patients who underwent ventriculoperitoneal shunt (VPS) between February 2001 and May 2012. Of these, 6 patients had chronic compensated hydrocephalus. The clinical and radiological characteristics are evaluated. Results: Definite triventriculomegaly was observed in two patients. Macrocephaly was observed in two cases, one with aqueductal stenosis (AS), the other with unknown status of aqueduct. All of the cases with triventriculomegaly were normocephalic. Spinal causes were thought as aggravating factor in two. Two endoscopic third ventriculostomy and eight VPS were performed in five patients. Four patients responded well but one took a very complicated course. Conclusion:The relationships between macrocephaly, triventriculomegaly, and AS suggested in other studies were inconsistent. Blockage or narrowing of cerebrospinal fluid pathways were observed at various sites. Disturbances of spinal arachnoid pathways were related to the activation in some cases. Treatment is to be tailored individually considering various reigniting event. It is suggested that this entity is to be evaluated for better nomenclature reflecting diverse aspects of this condition. Further study is needed to elucidate underlying pathophysiology and effective management. (Korean J Neurotrauma 2012;8:139-145) KEY WORDS: Hydrocephalus ㆍLong-standing overt ventriculomegaly in adult ㆍMacrocephaly ㆍAqueductal stenosis.