Platelet volume, also known as platelet volume, is the size of the platelets. The range of normal platelet volume is 7-11fl. Anything above or below the normal range is abnormal, and anything above 11fL is a large platelet volume. In clinical practice, large platelet volume is common in people with excessive platelet destruction in peripheral blood and good bone marrow hematopoietic function at the same time, such as patients with immune thrombocytopenic purpura, due to the destruction of platelets in peripheral blood, the larger platelets in bone marrow are released, resulting in an increase in platelet volume. Small blood cell volume is commonly seen in bone marrow hematopoietic disorders, such as aplastic anemia, where smaller platelets are formed due to hematopoietic stem cell hematopoietic failure, resulting in small platelet volume. In addition, some patients with acute myeloid leukemia also have a small platelet volume.