Management and problems of prolonged survival with hydranencephaly in the modern treatment era.

PURPOSE: Hydranencephaly is a rare condition that occurs during embryogenesis after neurogenesis and is characterized by the near complete absence of the cerebral hemispheres. In general, patients with hydranencephaly have been considered to have a markedly reduced life expectancy. We present 4 patients with hydranencephaly who have survived for over 5 years. The management and problems encountered in these cases are discussed. METHODS: A retrospective review was conducted at our institution. Medical charts and radiographic studies were reviewed. Data including age at follow-up, sex, clinical complications, and surgical procedures were recorded. RESULTS: Six patients were radiologically diagnosed with hydranencephaly during the period from January 2000 to December 2012. Two patients were excluded from our study: one because of death from pneumonia at 1 year of age and another because of transfer to another hospital. Four patients (3 males and 1 female) were included in the analysis. All 4 patients underwent ventriculoperitoneal shunt (VPS) placement and shunt revision. VPS infection occurred in 3 of 4 cases, and bloody cerebrospinal fluid (CSF) was observed in 2 of 4 cases. One patient underwent successful choroid plexus cauterization (CPC) and shunt removal after shunt infection. CONCLUSIONS: Prolonged survival with hydranencephaly is not unusual in the modern treatment era. CSF shunt problems, such as recurring shunt malfunction and shunt infection, represent one of the major problems, and avoiding CSF shunt with CPC is particularly desirable in patients with hydranencephaly.

Porencephaly and hydranencephaly in six dogs.

A retrospective study was performed to identify dogs with cerebrospinal fluid-filled cavitatory lesions on MRI. Six dogs were included and the lesions were classified. In the three dogs in the present study with hydranencephaly, unilateral but complete loss of the temporal and parietal lobes was noted and had almost complete loss of the occipital and frontal lobes of a cerebral hemisphere. In the three dogs with porencephaly, there was unilateral incomplete loss of the parietal lobe and one dog had additional partial loss of the temporal and frontal lobes. Two of the dogs with porencephaly had seizures; the third showed no associated clinical signs. The dogs with hydranencephaly had mentation changes and circled compulsively. The two porencephalic dogs with seizures were treated with phenobarbitone. One of the dogs with hydranencephaly showed increased frequency and duration of circling; one dog's clinical signs did not progress and the third dog was euthanased due to increasing aggression. The dog with increased circling had ventriculoperitoneal shunt placement and the circling frequency reduced.

Percutaneous choroid plexus coagulation in hydranencephaly.

Percutaneous intracranial endoscopy, performed on 3 infants with hydranencephaly and signs of intracranial hypertension, showed normal choroid plexus and choroid arteries in 2 patients. Transendoscopic coagulation of the arteries and plexus alleviated intracranial hypertension postoperatively. Minimal choroid plexus and no choroid arteries were present in the 3rd patient and coagulation did not alter the clinical course. Computerized tomography scans of the infants with normal choroid plexus demonstrated cerebral tissue in the region of the caudate nucleus; the child with minimal choroid plexus had tissue only in the region of the posterior thalamus.