Thrombogenesis on collagen surface under flow. Whole blood from Adamts13^+/+ or Adamts13^–/– mice containing mepacrine-labeled platelets was perfused over an acid-insoluble type I collagen-coated surface at a wall shear rate of 750 s^–1. The cumulative thrombus volume, analyzed using a multidimensional imaging system, was measured every 0.5 minute until 5.5 minutes. Data are the mean ± SEM of 5 mice for each genotype. *Significant differences at P < .05 in comparison with Adamts13^+/+ mice.