Aqueductal Compression by Dilated Virchow-Robin Spaces in the Mesencephalic-Pontine Region Presenting with Symptoms Mimicking Normal Pressure Hydrocephalus: A Case Report and Review of Literature.

Abstract

Dilatation of Virchow-Robin spaces (dVRS) have been described in the development of hydrocephalic syndromes. We report an unusual case of a type III dVRS presenting as a mimic of normal pressure hydrocephalus (NPH), due to distortion at the level of the cerebral aqueduct. A 59-year-old woman presented with mild traumatic brain injury and possible NPH, due to a history of progressive gait disturbance, recurrent falls, and cognitive decline over a year, in the context of ventriculomegaly. Detailed structural imaging of the brain revealed multiple dilated cystic lesions consistent with dVRS causing distortion at the level of the cerebral aqueduct. Cerebrospinal fluid examination was negative for infection. The patient was treated with endoscopic third ventriculostomy; at 12 months postoperatively, she demonstrated a sustained improvement in gait and stabilization of cognitive decline. This is an illustrative case of a subacute obstructive hydrocephalus due to a collection of periaqueductal dVRS, leading to an insidious clinical presentation mimicking NPH. We reviewed the literature for key clinical presentations and describe neuroanatomical considerations as well as primary treatment strategies. Various hydrocephalic syndromes may present with classic symptoms from Hakim's triad; such symptoms are not specific to idiopathic NPH. Both endoscopic third ventriculostomy and shunting may be efficacious. In our case, dVRS may serve as both a cause of and compensatory mechanism in a subacute obstructive hydrocephalus of unknown etiology. Our case highlights the need to understand the neuroanatomy of aberrant cerebrospinal fluid spaces in hydrocephalic syndromes. Further studies of dVRS would provide valuable insights into the pathogenesis of hydrocephalus.