Study Of M1 Segment Of Middle Cerebral Artery In Human Cadaveric Brains With Clinical Implications Of Its Early Branches

ABSTRACT

Background: Human brain gets its nutrition from carotido and vertebro-basilar system of vessels. MCA, being thelarger terminal branch of ICA supplies the cortical areas of brain concerned with speech and language. It is themost commonly involved artery in cerebro-vascular accidents as in stroke which is characterised by suddenonset of focal neurological deficit. The anatomical study is of utmost important to neurovascular surgeons.Materials and methods: The present study was undertaken in 140 cadaveric human brain hemispheres of 70formalin fixed brains from Department of Anatomy and Forensic medicine of Mysore medical college and ESICMC and PGIMSR, Bangalore. Fixed brains were sagitally bisected into right and left halves by brain cutting knife.Meninges were cleared and MCA was identified which was the larger and direct branch of ICA. Measurements ofICA and MCA was taken using thread and measuring scale. LSAs arising from MI segment MCA were counted usinghand lens. Any early branch if present was noted. Angle was noted between M1 and M2 segment. Presence of anyanomalies were studiedResults: The mean of length of M1 was found slightly more on the left side (2.09 cms) in comparison to right side(1.90 cms). The mean diameter of M1 segment of MCA was more on the left side (0.352 cms), in comparison toright side (0.317 cms). The mean diameter of left MCA (0.352 cms) and left ICA (0.359 cms) were of the same size.The mean diameter of right MCA (0.317 cms) and right ICA (0.323 cms) were almost of the same size. The numberof LSAs were more on left side (5.9) in comparison to right side (5.67). Early branches were found to be more onright side (5) than left side (3). The angle was observed to be acute in all specimens.Conclusion: This study was undertaken due to its clinical significance to stroke. Observations made on MCArevealed greater length of MCA carrying greater proportion of blood flow to the left side – a feature whichsupports the concept of vascular asymmetry. The knowledge of early branch arising from proximal segment ofMCA is helpful for neurovascular surgeons to make a fairer decision in planning the treatment for any neurovsculardisorders. The authors felt the necessity of documentation of data inferred by our study as there are very fewarticles on MCA found published in Indian literature.