Aneurysmal bone cyst of skull - case report and review of literature

We report a case of Aneurysmal Bone Cyst ABC] arising in a rare location [Skull] of three years old female child presented at Department of Neurosurgery, Jinnah Postgraduate Medico I Centre, Karachi with history of gradually increasing swelling in parietal region since birth. Tumour was excised with clinical diagnosis of dermoid cyst. Histological examination revealed an aneurysmal bone cyst. A three year old female child presented with complaints of gradually increasing swelling on parietal region of the skull since birth. C.T. Scan showed lytic bone lesion. Excision of the lesion was done and submitted for histopathological examination. Examination revealed a whitish firm mass measuring 10xbx5 cms in dimension. The outer surface was smooth. Cut surface shows numerous dilated spaces of varying sizes and shapes separated by thick fibrous septae containing brownish and yellowish gelatinous material. Some spaces were empty. Microscopic Examination: Revealed a bone with lytic lesion composed of numerous blood filled cavernomatous spaces widely separated by fibrous connective tissue septae of variable cellularity. The walls of the cavernomatous spaces lacked normal features of blood vessels with no lining endothelial cells Multinucleated giant cells were prominent in some part of connective tissue. Osteoid and formation of new bony tissue was evident in some septae