Hydranencephaly

• Etiology: In utero bilateral internal carotid artery occlusion due to in utero TORCH infection, vascular accident, hypoxic ischemic encephalopathy, maternal carbon monoxide or butane inhalation
• Imaging:
  — Have cranial vault
  — Absent anterior cerebral and middle cerebral arteries with no intact pial vessels or capillary blush
  — Cortical plate and hemispheric white matter destroyed and replaced by thin walled cerebrospinal fluid spaces leading to porencephaly of nearly entire cerebral hemisphere
  — Focal globular areas of parenchyma in inferior frontal, temporal and occipital lobes
  — Variable presence of thalami and basal ganglia
  — Preservation of brainstem and cerebellum
• DDX: Severe hydrocephalus and differentiating features of hydranencephaly from severe hydrocephalus which is possibly treatable:
  — Absent anterior cerebral and middle cerebral arteries with no intact pial vessels or capillary blush
  — Usually not macrocephalic
  — Focal globular areas of parenchyma in inferior frontal, temporal and occipital lobes
  — No diffuse uniform thin gray matter and white matter rim as in hydrocephlus
• Complications:
• Treatment: Not compatible with life
• Clinical: Normal size head

Radiology Cases of Hydranencephaly