Extramedullary Hematopoiesis Assessment in a Patient With Osteopetrosis

A 23-year-old patient with osteopetrosis had Tc-99m SC scintigraphy to evaluate the bone marrow stores and possible foci of extramedullary hematopoiesis. The bone marrow scan showed depleted bone marrow stores in the bones, but significant extramedullary foci of hematopoiesis in the liver, spleen, and pelvis. SPECT images of the bone marrow and x-ray CT images of the abdomen and pelvis accurately localized the extramedullary foci of hematopoiesis.