“…As factors for poor recanalization, anatomical vascular anomalies (bovine type, aortic arch type II/III, and ICA dolichoarteriopathy), sites of occlusion (cervical ICA, intracranial ICA other than T occlusion, and M2), marked stenosis of the cervical ICA, large-volume thrombi, tandem lesions, hard thrombi, non-embolic features, rare stroke type, overtime medical service, female sex, a history of hypertension, and treatment for many hours have been reported. [4][5][6][7] In the present case, the second pass led to recanalization at the site of M1 occlusion, but a hard, giant thrombus involved the area of dolichoarteriopathy with a round structure at the site of cervical ICA occlusion, making thrombectomy difficult. At the origin of the ICA, there was no arteriosclerotic or dissecting lesion, but dolichoarteriopathy of the ICA and the hard thrombus affected recanalization.…”