TOAST (trial of ORG 10172 in acute stroke treatment) Criteria
Large Vessel Atherosclerosis (>50% stenosis): cortical, cerebellar or brainstem and subcortical lesions (greater than 1.5 cm)
Cardioembolism: cortical, cerebellar or brainstem and subcortical lesions (greater than 1.5 cm); consider if more than one vascular territory
Small Vessel Disease: subcortical or brainstem (pontine) lesion usually less than 1.5 cm; hx of diabetes or hypertension supports diagnosis
Stroke of Other Determined Etiology: can be cortical or subcortical; rarer causes of stroke such as hypercoaguability, inflammatory/noninflammatory vasculopathies, hypoperfusion, paradoxical embolus (PFO) among others
Stroke of Unknown Etiology (Cryptogenic): if greater than 2 potential causes of stroke, incomplete diagnostic evaluation, or unknown etiology