|| Checking for direct PDF access through Ovid
Background and Purpose: Thrombus composition has been suggested to have a decisive impact on the outcome of patients treated by mechanical thrombectomy because of embolic stroke. The aim of this prospective study was to assess the impact of a mechanical thrombectomy device (Penumbra aspiration catheter vs. Stent retriever) on thrombus composition, which could affect flow impairment after reperfusion.Methods: Thrombi of consecutive stroke patients with large vessel occlusion were collected during intracranial mechanical recanalization. Mechanical thrombectomy device was used either Penumbra aspiration catheter or Stent retriever. The hematoxylin and eosin-stained specimens were quantitatively analyzed in terms of the relative fractions of the main constituents (red blood cells and fibrin/platelets).Results: Of 65 cardio-embolic patients, Penumbra aspiration catheter was used in 27 patients, and Stent retriever was used in 38 patients. There was no significance in age, sex, occlusion vessel, NIH stroke scale, and onset to reperfusion time. The volume of thrombi was significantly larger in Penumbra group compared with that in Stent group (3.68 cm3 vs. 0.95 cm3, P<0.01). On the other hand, The percentage of fibrin component was significantly higher in Stent group (36.2% vs. 62.4%, P<0.01). Preoperative IV-tPA reduced the size of thrombi in Stent group, which was not seen in Penumbra group (0.46 cm3 vs. 1.26 cm3, P<0.01). Interestingly, preoperative susceptibility vessel sign on MR imaging correlated with the percentage of red blood cells in not Stent group but Penumbra group. Finally, new infarction on MR imaging was not different between two groups 24 hours after the treatment.Conclusions: Stent retriever could crush thrombus and reduce its size, which induce distal migration of the red blood cell component. However, it did not affect the final infarct lesion and outcome.