EXPANDING CYST OF THE SEPTUM PELLUCIDUM - CASE-REPORT

Expanding cysts of the septum pellucidum, although rare, may be a caus e of significant neurological dysfunction. Most become symptomatic as a result of obstruction of the interventricular foramina and produce h eadaches, papilledema, emesis, and loss of consciousness. Behavioral, autonomic, and sensorimotor symptoms occur when an expanding cyst impi nges on the structures of the hypothalamoseptal triangle or impairs th e deep cerebral venous drainage. Neuroophthalmological symptoms may de velop as a consequence of hydrocephalus or direct compression of visua l structures. The authors describe the case of a young boy with an exp anding septum pellucidum cyst who presented with a sudden, severe head ache and loss of consciousness. In addition, he had a history of hyper activity and progressively declining school performance. All symptoms resolved following decompression of the cyst. Seventeen cases from the literature are reviewed. The pathophysiological mechanisms underlying the development of symptoms secondary to expanding septum pellucidum cysts are outlined, and the related clinical neuroanatomy is described . A model is proposed for the natural history of expanding septum pell ucidum cysts that provides a rational basis for understanding their cl inical behavior and response to intervention. In most cases, fenestrat ion or shunting will relieve the obstructive hydrocephalus and mass ef fect caused by the cyst and will produce rapid symptomatic improvement .