Histological analysis of cystic tumour like lesions of central nervous system

True cysts of the central nervous system (CNS) are rare lesions. A retrospective study of patients with symptomatic non-neoplastic cystic lesions of CNS operated in the Department of Neurosurgery, G.B. Pant Hospital, New Delhi between Jan 1994 and Feb 2001 was conducted. Parasitic cysts, cystic transformation of hemmorhages, vascular malformations and cystic tumours were excluded from the study. A total of 109 cases were reviewed. There were 34, 27, 17, 16, 8, 3 and 2 cases of epidermoid, arachnoid, dermoid, colloid, neurenteric, Rathke's and ependymal cysts and 1 case each of choroid plexus and glial cysts. The clinical presentations, locations, incidence and pathogenesis of these cysts is discussed.