Two types of cerebral hemiatrophy are reported from the Institute of Neuropathology at the University of Giessen, Arndtstrafse FRG. A case of “primary cerebral hemiatrophy” is described in a 12 year old boy whose birth was difficult and complicated by perinatal asphyxia. Seizures occurred immediately after birth and the psychomotor development was slow. He had spastic diplegia, asymmetrical, the right side predominating. He died at 12 years of age with cardiac arrest after status epilepticus. At autopsy the left hemisphere was reduced in size, the left lateral ventricle was enlarged and the white matter was decreased, especially on the left. The cerebral peduncles and pyramidal tracts were asymmetrical, and the neurons of the left hippocampus were replaced by glial tissue. Case two, an adult male, had a normal birth and early development and suffered from convulsions at two years of age which were followed by a right hemiparesis and homonymous hemianopsia. CT scan showed cerebral hemiatrophy and skull hypertrophy on the left side. The patient died at the age of 58 from intestinal hemorrhage with liver cirrhosis. The left cerebral hemisphere was atrophied and with crossed cerebellar and pyramidal tract atrophy. There was loss of cortical neurons in the atrophic left hemisphere and replacement by glial cells, a spongy state and abundant corpora amylacea. This was an example of “secondary cerebral hemiatrophy”. The authors propose a classification of primary and secondary cerebral hemiatrophy. The primary forms are caused by vascular malformation, perinatal asphyxia and birth trauma and result in ulegyria, lamina necrosis and leukoencephalopathy. The secondary forms may be post-ictal with or without fever, cerebrovascular accident or leukoencephalitis. The pathological findings with the secondary form are sclerosing cortical atrophy and occasionally leukoencephalopathy. 
COMMENT. Cerebral hemiatrophy with homolateral hemihypertrophy of the skull and sinuses was described by Dyke CG, Davidoff L, and Masson C.  and Alpers B J, and Dear R B  distinguished the primary and secondary groups of cases. The significance of convulsions in the pathogenesis of cerebral hemiatrophy is emphasized by many authors - the “hemiconvulsion hemiplegia - epilepsy syndrome.” Permanent hemiparesis as a direct result of a febrile convulsion is a rare complication occurring in less than 0.2%.