Visual Failure Caused by Suprasellar Extramedullary Hematopoiesis in Beta Thalassemia: Case Report

Objective And Importance: Small deposits of extramedullary hematopoiesis, acting as epileptogenic foci, have been observed near convexity dura and adjacent to falx 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, with progressive visual loss caused by extramedullary hematopoiesis originating 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 pre-sphenoid cranial base and approaching the lower third ventricle.

Intervention: Partial resection of the tumor was accomplished by a transsphenoidal approach. Monthly blood transfusions and low-dose radiotherapy of the appropriate anatomic structures were then performed. The patient's visual acuity improved only modestly.

Conclusion: Extramedullary hematopoiesis, although extremely rare, could arise from the base of the cranium and act as a parasellar tumor. When any patient with thalassemia major requiring multiple transfusions develops visual failure, appropriate studies should be performed to rule out compression of visual pathways by ectopic marrow, especially if the patient is receiving deferoxamine.