Hemodynamically significant venous collapse underlying neonatal hydrocephalus

Abstract

Object It is known that CSF diversion in neonatal hydrocephalus can significantly increase cerebral blood flow, suggesting that a rapidly reversible elevation in vascular resistance underlies this disorder. Various sites of vascular compression have been described in the literature, from the arterioles to the capillary bed to the venules and sinuses. The purpose of this study was to define the site of the hemodynamically significant vascular compression seen in neonatal hydrocephalus. Methods The author performed a retrospective review of all patients who, in the first 28 days of life, had undergone 3-T MRI examination, including MR venography and susceptibility weighted scanning, at a tertiary care referral hospital in the period from April 2010 to April 2013. The maximum size of the subependymal veins over the thalamus and transverse sinuses was measured. Results Three children with hydrocephalus were identified, and 10 children with a normal ventricular size served as controls. The subependymal veins were twice as prominent and the transverse sinuses were half as large in the patients with hydrocephalus compared with those in controls. Conclusions The hemodynamically significant elevation in vascular resistance, which occurs in neonatal hydrocephalus, appears to be located in the venous sinuses.