Morphometric Study of Basilar Artery in the Eastern Indian Population.

INTRODUCTION: The basilar artery (BA) is formed by the fusion of right and left vertebral arteries and divides to form right and left posterior cerebral arteries. This study was done to provide a baseline database regarding length, mid-length diameter, level of origin, and level of termination of BA. MATERIALS AND METHODS: Thirty-eight formalin-fixed brains were obtained from cadavers dissected for undergraduate studies. The external length and the average external diameter of BA were measured by a digital Vernier caliper. Variation in origin and termination of BA was noted using magnifying glass. RESULTS: The length and diameter of the BA were 25.58 ± 3.57 mm and 3.05 ± 0.41 mm, respectively. The origin and termination of BA was normal in most cases. In two cases, the origin was above the pontomedullary junction, and in one case, it was below. In two cases, the termination was above the pontomesencephalic junction, and in one case, it was below. CONCLUSION: There was no gender predisposition in length and diameter of the basilar artery. The baseline data established in this study regarding length, diameter, level of origin and level of termination of basilar artery will help neurosurgeons and interventional radiologists to diagnose as well as plan and execute various vascular procedures such as shunting for the treatment of aneurysms and stenosis in the blood vessels of the posterior cranial fossa.

The Ossified Bifid Superior Transverse Scapular Ligament Causing a Double Suprascapular Foramen: A Case Report.

Ossified bifid superior transverse scapular ligament causing a double suprascapular foramen is a very rare finding. This ossified ligament reduces the suprascapular space by half of its original size. It is one of the precipitating factors of suprascapular nerve entrapment. Here we describe a double suprascapular foramen in a dry left scapula of Indian origin. There were two bony bars bridging the suprascapular notch thereby making two foramina. The bony bars were 'V' shaped with its apex attached to the lateral side of the suprascapular notch. The upper foramen was large and triangular whereas the lower foramen was small and oval. Considering the shape of the foramen and the 'V' shaped attachment of the bony bars, we conclude it to be due to the ossification of bifid superior transverse scapular ligament. A double suprascapular foramen should always be kept in mind while diagnosing and treating suprascapular nerve entrapment. Knowledge about the double suprascapular foramen would be useful to orthopaedic surgeons who perform decompression for suprascapular nerve entrapment through arthroscopy and open procedures.