Hydranencephaly Associated with Interruption of Bilateral Internal Carotid Arteries

Abstract

Hydranencephaly is a rare and fatal central nervous system disorder where all or nearly all of the bilateral cerebral hemispheres are absent. The extensive hollow cerebrum is replaced with cerebrospinal fluid. Clinically, the differential diagnoses of hydranencephaly include severe hydrocephalus and alobar holoprosencephaly. Nearly all cases are sporadic, involving approximately 1 in 5000 continuing pregnancies. The exact main cause is still unknown, but hydranencephaly is usually found to develop secondarily to the occlusion of cerebral arteries above the supraclinoid level. We present the case of a 1-month-old male infant with hydranencephaly initially thought to be severely hydrocephalus via routine antenatal intrauterine sonography performed at 35 weeks of gestation. Hydranencephaly was confirmed by brain sonography, brain magnetic resonance imaging and magnetic resonance angiography postnatally. We discuss several imaging features that are helpful in distinguishing hydranencephaly from extreme hydrocephaly. Different theories that have been recently proposed regarding the origin of hydranencephaly are reviewed.

Volumetric analysis of cerebrospinal fluid and brain parenchyma in a patient with hydranencephaly and macrocephaly – case report

“…Hydranencephaly is a difficult and rare developmental disorder that occurs in fewer than 1 of 10 000 newborn children, most likely due to bilateral occlusion of the internal carotid artery between 8 and 12 weeks of pregnancy (1-3). It is often characterized by heavy malacia of the supratentorial structures perfused by the anterior and middle cerebral arteries.…”

“…It is often characterized by heavy malacia of the supratentorial structures perfused by the anterior and middle cerebral arteries. Smaller remaining parts of the supratentorial functional parenchyma are located in the area of diencephalic structures and in the areas of the temporal and occipital lobes that are perfused by the posterior cerebral artery (1,3,4). Infratentorial structures are usually morphologically fully developed and functional, and patients are able to perform functions such as suction, swallowing, crying, and moving of the extremities (5-7).…”

Poland anomaly and hydranencephaly: An unusual association

“…Hydranencephaly is defined as severe dysgenesis of the cerebral hemispheres, with relative preservation of the thalamus, cerebellum, and brainstem [Stevenson et al, 2001; Quek et al, 2008]. Hydranencephaly has been hypothesized to be due a vascular disruption arising from the internal carotid arteries.…”

Hydranencephaly: cerebral spinal fluid instead of cerebral mantles

“…This may be due to the different pathogenetic events inducing the two different forms, and perhaps, also to missed HE diagnosis in favor of similar disorders. In fact, as many as 1% of infants thought to have hydrocephalus by clinical examination were later found to have hydranencephaly [ 18 ] and vice versa. Cecchetto et al [ 16 ], in their review, reported information from 37 different publications on this topic and collected examples of 76 patients from the literature.…”