Perfusion study is only indicated in patients with more than 6 hours of onset symptoms, if eligible for mechanical thrombectomy !
More than 6 hrs ?
It should be less than 6 hours ?
To ascertain salvagable area if any. After 6 hrs there ll be irreversible injury.?
Perfusion study and multiphasic angio is done to decide patient eligibility for endovascular management after iv tpa therapy within window period of 4.5 hr decided on basis of ncct or mri ( dwi , flair , swi).
Eligibility for endovascular management of stroke
- ischemic penumbra to infarct core ratio >=1.8 or absolute mismatch >15 ml
2)single phase cta score 2 and 3
- multiphasic cta score 4 and 5