MEASUREMENT OF SPLEEN SIZE USING GAMMA-CAMERA SCINTIGRAPHY IN ESSENTIAL THROMBOCYTHEMIA

By using gamma camera imaging the spleen size was determined in 33 con secutive patients with essential thrombocythaemia (ET) and in 33 conse cutive patients with reactive thrombocytosis (RT). All ET patients wer e newly diagnosed and had not received myelosuppressive treatment prio r to study; they all fulfilled the criteria for ET as established by t he Polycythemia Vera Study Group. In both posterior and lateral projec tions, the spleen area in the group of ET patients was significantly l arger than in the RT patients. The present study has shown that 39% of ET patients at diagnosis have splenic enlargement. Evaluation of sple en size is therefore a useful diagnostic test in patients presenting w ith unexplained thrombocytosis.