Clinical Significance of Sclerosis of the Cornu Ammonis

IN A LECTURE delivered in 1927, Spielmeyer¹referred to sclerosis of the cornu ammonis as "this often-described, yet hitherto enigmatic, phenomenon." This statement is still true, even though the pathogenesis of the phenomenon has since been elucidated to a great extent by Spielmeyer himself and his associates. The first gross description of this lesion is generally credited to Bouchet and Cazauvieilh,²who, in 1825, observed changes of sclerosis or softening in the hippocampus of epileptic as well as of nonepileptic psychopathic patients. The first microscopic examination was done in 1880 by Sommer,³who found the changes to be restricted to the band of pyramidal cells of the hippocampus. The latter area has since been called "Sommer's sector." In 1889 Chaslin⁴described a marginal gliosis in cases of epilepsy and regarded sclerosis of the cornu ammonis as representing merely a site of predilection for such gliosis. Bratz