Improved platelet counting using two-dimensional laser light scatter

Clinical management of platelet disorders depends on accurate platelet coun ts. We evaluated a new analytic approach for platelet counting based on imp roved platelet discrimination, Current automated counting methods provide a ccurate platelet counts for most samples but often are unable discriminate platelets accurately from nonplatelet particles such as microcytic RBCs, RB C fragments, and cellular debris that may falsely elevate platelet counts. The new approach measures 2 light-scatter angles of platelets and nonplatel et particles as they pass through a laser beam. The volume and refractive i ndex of each platelet and particle are derived from the light-scatter measu rements using the Mie scattering theory. Together these 2 measurements prov ide improved platelet discrimination compared with I-dimensional methods. W ith its improved discrimination, 2-dimensional platelet analysis provides m ore accurate platelet counts in samples containing interfering particles an d may contribute to more effective clinical management of patients with pla telet disorders.