18F-FDG PET/CT in a 16-Year-Old Patient With Hydranencephaly

ABSTRACTA 16-year-old male patient with a past medical history of congenital brain malformation presented for surveillance F-FDG PET/CT scan of left parotid acinic cell adenocarcinoma. F-FDG PET/CT revealed absence of gray matter activity in the bilateral cerebral hemispheres most consistent with hydranencephaly. Hydranencephaly is a rare congenital condition characterized by absent cerebral hemispheres replaced by cerebrospinal fluid–filled sacs. The etiology is hypothesized to be secondary to intrauterine bilateral internal carotid artery compromise. Most affected individuals die in utero or within weeks of birth; however, there are rare reported cases of prolonged survival as in our patient.