THE PATHOLOGY OF POLIOMYELITIS

Because of the nature of the disease, the early lesions of acute poliomyelitis or infantile paralysis in man are accessible for study only at necropsy, and it is from such material that the cytopathologic picture has been built. Although the chordal and bulbar lesions afford the chief sources for clinical expressions of the disease in the form of palsies, the damaging effects of the infection in the central nervous system are more widespread. Focal areas of injury are present in most if not all cases in the pons, brain stem, motor cortex and meninges, so that a more descriptive terminology would appropriately designate the pathologic-anatomic aspects of the nervous involvement as meningoencephalomyelitis. Evidences of injury have been found likewise in the dorsal root ganglion, and a more complete search would probably disclose lesions rather constantly in these structures and perhaps likewise in peripheral ganglions. Some investigators have attached perhaps too