Pathophysiology of long-standing overt ventriculomegaly in adults

Abstract

EFORE recent diagnostic procedures were introduced for the diagnosis of hydrocephalus, one of the most accepted indicators for progressive hydrocephalus in infants was head circumference. However, formulating a diagnosis of arrested hydrocephalus on the basis of this indicator alone would be questionable. Whittle and colleagues 41 used continuous ICP monitoring to as-sess 46 children and adolescents in whom a clinical diagnosis of arrested hydrocephalus had been made. They found that 80% of patients who had previously been treated had a nonfunctioning shunt and that 63% of patients who had received no previous treatment had episodic or persistent increased ICP. When serial psychometric testing demonstrated a fall in cognitive functioning, ICP monitoring revealed abnormal ICPs in 88% of patients. The results of this study may indicate that CSF dynamics change over time, shifting hydrocephalus between active and inactive states; however, the factors affecting such changes remain uncertain.In 1996, we reported on the specific clinical features of infantile hydrocephalus that continues into adulthood, Object. Long-standing overt ventriculomegaly in adults (LOVA) is a unique form of hydrocephalus that develops during childhood and manifests symptoms during adulthood. The aim of the present study was to analyze the specific pathophysiological characteristics of LOVA.Methods. The specific diagnostic criteria for LOVA include severe ventriculomegaly in adults that is associated with macrocephalus measuring more than two standard deviations in head circumference and/or neuroradiological evidence of a significantly expanded or destroyed sella turcica. Twenty patients who fulfilled these criteria, 14 males and six females, were retrospectively studied. These patients' ages at diagnosis ranged from 15 to 61 years (mean 39.4 years). All had symptoms and/or signs indicating that hydrocephalus first occurred at birth or during infancy in the absence of any known underlying disease. The authors performed a pathophysiological study that included specific variations of magnetic resonance (MR) imaging, such as fluid-attenuated inversion recovery and cardiac-gated cine-mode imaging; intracranial pressure (ICP) monitoring; three-dimensional computerized tomography (CT) scanning; and other techniques.Hydrocephalus was caused by aqueductal stenosis in all patients. Severe ventriculomegaly involving the lateral and third ventricles was associated with a marked expansion or destruction of the sella turcica in 17 cases. Cardiac-gated cine-MR imaging did not reveal any significant movements of cerebrospinal fluid in the aqueduct. Three-dimensional CT ventriculography confirmed that the expanded third ventricle protruded into the sella and, sometimes, extended a diverticulum. Fourteen patients revealed symptoms and signs that indicated increased ICP with prominent pressure waves. Dementia or mental retardation was seen in 11 patients, gait disturbance in 12, and urinary incontinence in eight; all three of these symptoms were observed in sev...

Subdural Hygroma as a Complication of Endoscopic Neurosurgery. Two Case Reports.

“…Many authors state that CSF flows from the third ventricle into the basal cisterns via the subarachnoid space of the interpeduncular cistern. 8,15,20,33,34) CSF volume following ETV is dependent upon the``normal'' pathways of absorption, so producing a slower decompression of the ventricular system and minimizing the risk of subdural collection of any kind. Furthermore, to prevent a collapse of the ventricular system, which would be the simplest explanation for the formation of the subdural hygroma, only a minimal amount of CSF is lost during the intervention.…”

“…2,29,31) Acute or chronic subdural hematoma or hygroma are wellknown complications after extracranial shunting, and are considered to be overdrainage-related phenomena. 9,13,26,32,34,37,49) We report two cases of subdural hygroma which occurred in a series of 77 neuroendoscopic procedures and discuss the possible etiologies as well as the surgical and clinical consequences.…”

Syndrome of hydrocephalus in young and middle-aged adults: Review of the literature and illustrative cases

“…The first systematic review in this age group was first described by S. Oi in mid-nineties as Longstanding Overt Ventriculomegaly in Adults (LOVA) (7). LOVA is a relatively new concept -a specific form of non-communicating hydrocephalus that often causes hydrocephalic dementia.…”

Hydrocephalus Research Update -Controversies in Definition and Classification of Hydrocephalus-

“…In the field of Hydrocephalus Research in adults, there is growing new consensus of entities other than classical``normal pressure hydrocephalus'' (NPH), which have been always debatable in the concept of this entity. 12,30) Based on such various characteristics in hydrocephalus, with more and more new aspects recently disclosed not only in fetal and pediatric but also in adult hydrocephalus, the current status of classification of hydrocephalus in the individual subgroup was reviewed focusing on the critical points of the individual category of hydrocephalus. …”

“…30) Although its mechanism still remains unclear, patients with LOVA often suffer from a progressive course of hydrocephalus that continues into adulthood. We also reported that the hydrocephalic state in LOVA is extremely difficult to treat with a shunt because of lost intracranial compliance.…”