PERINATAL PATHOLOGY OF INTERHEMISPHERIC CYST WITH THINNED POSTERIOR CORPUS-CALLOSUM - 4 CASES

This paper presents four posterior, interhemispheric cerebral cysts fo und at perinatal autopsy. All cysts appeared to attenuate the overlyin g posterior corpus callosum. All had a base over the roof of the third ventricle and midbrain with a lining that resembled tela choroidea wi th the choroid plexus tufts projecting into the lumen of the cyst. Thr ee cases had enlargement of the lateral ventricles. One case had compl ete communication between the cyst and the posterior lateral ventricle s reminiscent of a holoprosencephaly confined to the posterior telence phalon. One case demonstrated a complete VATER association and two oth ers had some features of the VATER association. We hypothesize that th is latter relationship suggest an origin for the cysts during blastoge nesis.