VISUAL FAILURE CAUSED BY SUPRASELLAR EXTRAMEDULLARY HEMATOPOIESIS IN BETA-THALASSEMIA - CASE-REPORT

OBJECTIVE AND IMPORTANCE: Small deposits of extramedullary hematopoies is, acting as epileptogenic foci, have been observed near convexity du ra and adjacent to fair cerebri. These foci could potentially grow and act as space-occupying lesions, producing focal neurological deficits . This condition was observed in a unique case of thalassemia major, w ith progressive visual loss caused by extramedullary hematopoiesis ori ginating from the base of the cranium and extending up to the inferior third ventricle. The patient had been operated on 4 years earlier to relieve the compressive effects of ectopic marrow in the thoracolumbar epidural space. CLINICAL PRESENTATION: A 21-year-old man is reported with progressive visual loss caused by compressive optic neuropathy as a result of extramedullary hematopoiesis. Computed tomography of the head revealed a suprasellar and parasellar enhancing mass originating from the presphenoid cranial base and approaching the lower third vent ricle. INTERVENTION: Partial resection of the tumor was accomplished b y a transsphenoidal approach. Monthly blood transfusions and low-dose radiotherapy of the appropriate anatomic structures were then performe d. The patient's visual acuity improved only modestly. CONCLUSION: Ext ramedullary hematopoiesis, although extremely rare, could arise from t he base of the cranium and act as a parasellar tumor. When any patient with thalassemia major requiring multiple transfusions develops visua l failure, appropriate studies should be performed to rule out compres sion of visual pathways by ectopic marrow, especially if the patient i s receiving deferoxamine.