OBJECTIVE. Conversion of bone marrow in the extremities from red to yellow is a normal maturation process. Marrow reconversion is present when expected yellow marrow is replaced with active red marrow, and it tends to occur at times of physiologic…
Sarcoidosis is a disease of unknown etiology which is characterized pathologically by widespread noncaseating granulomas involving multiple organ systems. We report a case of sarcoidosis presenting as a ventilation-perfusion mismatch on a lung scan.