Hi Fanfaire, i done a quick google and come up with this.

MPV – the mean platelet volume (MPV) it represents the average size of the platelets within a blood sample. This is a relatively new test and not included in by all laboratories. Measured in cubic micrometers or femtoliters, normal values are generally between 7 and 11 fL.
A reduced MPV is indicative of small platelets, and may be consistent with disorders such as aplastic anemia. An elevated MPV is encountered when platelets are larger than average, such as in Idiopathic Thrombocytopenic Purpura.

'" Platelets " may be counted to monitor or diagnose diseases, or identify the cause of excess bleeding.The number of The number of platelets in your blood can be affected by many diseases. Platelets may be counted to monitor or diagnose diseases, or identify the cause of excess bleeding.The number of platelets in your blood can be affected by many diseases.

Brian