The neuropathology of South American mummies

Few studies of intracranial mummified brain tissue have been undertaken. This is because of the infrequency in which preserved human central nervous system tissue is encountered and the scarcity of available mummies from different parts of the world. This study undertook a systematic analysis of 15 naturally mummified human brains from 1000 B.C. to 1500 A.D. excavated from the deserts of northern Chile. Gross examination revealed relatively well-preserved dura mater, cerebral hemispheres, cerebellum, and spinal cord in several cases. Five cases showed evidence of intracranial disease. Three cases had evidence of external injury. One case revealed subarachnoid and one case revealed intracerebral hemorrhage. Samples of central nervous system tissues were taken for further analysis. The samples were rehydrated and processed for structural analysis by light and electron microscopy. Light microscopy of the brain parenchyma revealed an eosinophilic staining background with vascular structures but few cellular elements present. The dura mater demonstrated normal dural architecture consisting of collagen fibrils. Electron microscopy did not clearly demonstrate individual neurons or axonal processes. Bundles of collagen fibrils with typical periodicity were clearly seen in the dura mater. The examination of ancient human central nervous system tissues reveals normal and abnormal neuroanatomy.