The foramen ovale morphometry of sphenoid bone in South Indian population.

BACKGROUND: The foramen ovale is an oval opening in the greater wing of sphenoid bone transmitting the mandibular nerve as its major content. It serves as an important landmark for neurosurgeons in certain procedures as to gain access to trigeminal nerve. Therefore, its topographic position in relation to adjacent bony landmarks provides useful tool during these procedures. AIM: To analyse the morphometric measurements of the foramen ovale among South Indian population. MATERIAL AND METHODS: Morphometric analysis was carried out on 104 foramina ovalia of 52 dry human skulls from South India. Following dimensions of foramen ovale were measured: antero-posterior length, transverse width, distance (d(1)) from tubercle of root of zygoma to the centre of the foramen (CF) and distance (d(2)) from the midline of the base of the skull to CF. RESULTS: The mean antero-posterior length was 7.0±2.17mm on right side and 6.8±1.40mm on left side, mean transverse width was 5.0±0.42mm and 4.70±0.91mm on right and left side respectively. Mean d(1) was 32.58±1.72mm on right side and 32.75±1.76mm on left side. Mean d(2) was 25.83±1.26mm on right side and 25.08±1.31mm on left side. CONCLUSION: Regional variations in the morphometric measures may be useful in neurosurgical procedures like administration of anaesthesia involving the mandibular nerve.

Anomalous branching pattern of the aortic arch and its clinical applications

The aortic arch gives rise to three classical branches, namely the brachiocephalic trunk, the left common carotid artery and the left subclavian artery. We report a rare variation of the left common carotid artery and the right vertebral arteries originating from the brachiocephalic trunk, and the left vertebral artery that was arising from the arch of the aorta, proximal to the origin of the left subclavian artery. Variations in the branching pattern of the arch of aorta can alter the cerebral haemodynamics that leads to cerebral abnormalities. Knowledge of the variations in the classical branches of the arch of aorta is important in the diagnosis of intracranial aneurysm after subarachnoid haemorrhage.