title: Homonymous Visual Field Loss without Structural Lesion on Magnetic Resonance Imaging: Documented with Positron Emission Tomography and Diffusion Tensor Imaging.
abstract: The authors describe a 35-year-old man suffering from homonymous hemianopia after head trauma 4 years before but with negative magnetic resonance imaging (MRI) findings. Brain fluorine-18 fluorodeoxyglucose positron emission tomography (18FDG-PET) showed hypometabolism at the unilateral occipital lobe and crossed cerebellar hemisphere, and diffusion tensor imaging (DTI) revealed that the ipsilateral optic radiations were completely interrupted. The crossed cerebellar diaschisis (CCD) observed in the chronic stage of brain damage was caused by cerebellar suppression of the cerebral blood flow due to an involvement of the corticopontocerebellar tract. PET and DTI provide objective means for determining the relationship of functional deficits to head trauma, even in cases where the injury was sustained years prior to the evaluation.
authors.affiliation: Department of Neurology, Chonbuk National University College of Medicine, and Research Institute of Clinical Medicine Chonbuk National University, Jeonju Korea.
authors.forename: Tae-Ho
authors.initials: TH
authors.lastname: Yang
authors.affiliation: Department of Neurology, Chonbuk National University College of Medicine, and Research Institute of Clinical MedicineChonbuk National University, JeonjuKorea; Biomedical Research Institute of Chonbuk National University HospitalJeonjuKorea.
authors.forename: Sun-Young
authors.initials: SY
authors.lastname: Oh
authors.affiliation: Department of Biomedical Engineering, Hanyang University Seoul Korea.
authors.forename: Kichang
authors.initials: K
authors.lastname: Kwak
authors.affiliation: Department of Biomedical Engineering, Hanyang University Seoul Korea.
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Lee
keywords: Crossed cerebellar diaschisis; diffusion tensor imaging; homonymous hemianopia; traumatic brain injury