Predicting Occluded Middle Cerebral Artery Morphology for Endovascular Mechanical Thrombectomy: A Contralateral Shape Analysis Approach.

Predicting the shape of the occluded middle cerebral artery (MCA) from the contralateral MCA might help catheterization in endovascular mechanical thrombectomy (EMT).  We analyzed magnetic resonance (MR) angiography in 100 consecutive patients who had MR imaging for diseases other than acute ischemic stroke. To assess the symmetricity of MCA, the shape of M1, length of M1, number of M2, number of early branches (EBs), and distance from the top of the internal carotid artery to EB were investigated.  The shape of M1 was upward in 42%, horizontal in 47%, and downward in 11%. The M1 shape was the same on both sides in 64%, which exceeded the probability assumed to be left-right independent. The number of M2 trunks and EBs matched left and right in 86 and 55% of patients, respectively; however, these agreement rates were not higher than those with independent left and right sides. No left-right correlation was found between the M1 length and the distance from the internal carotid artery to EB.  Based on our data, the symmetry of MCA was observed only in the shape of the M1 segment. This finding could be beneficial for EMT targeting MCA embolisms.