Back ground:The foramen spinosum is one of important foramina located in the base of the skull on the greater wing of sphenoid bone situated posteriorlaterally to the foramen ovale, therefore it could be identified both from the exterior and interior of the skull base, externally the foramen spinosum pierces the spinous process of the sphenoid bone at its apex or medial aspect. Foramen spinosum transmits the passage of the middle meningeal artery, parietal trunk of the middle meningeal artery and posterior trunk of the middle meningeal vein to the middle cranial fossa. Materials and Methods:Total 300 skull were used for this study. The shape of foramen spinosum and diameter of it recorded with vernier calipers.Results: Foramen spinosum found as round shape in 58%, oval shape in 38% and irregular in 4%. The maximum diameter of foramen spinosum was 2.77+0.97mm and 2.03+0.56mm was minimum in females, in males maximum diameter was 2.95+0.56mm and 1.52+0.82mm as minimum. The knowledge of foramen spinosum is great helpful for neurosurgeons. Conclusion:The round shape was found in more number of skulls and very few were irregular shape. The knowledge of foramen spinosum help to cranial surgeons as it is transmitting middle meningeal artery.KEY WORLD: Foramen spinosum, Middle mengeal artery, dry skull, sphenoid bone.

Background: Pterion is defined as an H-shaped small circular area formed by the junction of four bones: frontal, parietal, temporal and sphenoid on norma lateralis of the skull, Pterion junction has been used as a common extra-cranial landmark for surgeons in microsurgical and surgical approaches towards important pathologies of this region. Pterion is an important landmark for anterior branch of middle meningeal artery, Broca's motor speech area to the left, insula, the lateral cerebral fissure, for the pathologies of optic nerve, orbit, sphenoidal ridge and for the anterior circulation aneurysm and tumors, because of its clinical importance we focused our present study on morphology of shape of pterion. Materials and Methods: A total of 500 pterions were examined from 250 adult dry skulls. The present study was undertaken in adult south Indian skulls from different regions of south India, from different medical colleges. We have observed different shapes of pterion like sphenoparietal frontotemporal, stellate and epipteric. Results: The sutural morphology of the pterion and asterion is important in surgical approaches to the cranial fossae. 250 human skulls of known gender (148 male, 102 female) were examined on both sides. Four types of pterion were observed-sphenoparietal 72.8%, frontotemporal 16.4%, stellate 8.8% and epipteric 2%. Conclusion: The pterion is points of sutural confluence seen in the norma lateralis of the skull. The patterns of formation exhibit population based variations. The sutural morphology of the pterion is important in surgical approaches to the cranial fossae. These findings may helpful in surgical approaches and interventions via the pterion.

Background:The asterion is the junction of the parietal, temporal and occipital bones. The asterion is a surgical landmark to the transverse sinus location which is of great importance in the surgical approaches to the posterior cranial fossa. The sutural morphology was classified into two types, Type I where a sutural bone was present and type II was where sutural bone was absent. The study of asterion may be helpful to ENT and Neurosurgeons. Materials and Methods:A total of 500 asterion were examined from 250 adult dry skulls. The present study was undertaken in adult south Indian skulls from different regions of south India, from different medical colleges. We have observed different types of asterion like Type I where a sutural bone was present and type II was where sutural bone was absent. Results:The sutural morphology of the asterion is important in surgical approaches to the cranial fossae. 250 human skulls of known gender (148 male, 102 female) were examined on both sides. Two types of asterion were observed -Type I was 18% in males, 20% in females and in total, Type II was 82% in males, 80% in females and 81% in total. Conclusion:Sutural morphology of the asterion in the Indian population does not differ much from that of other populations. These findings useful in surgical approaches and interventions via the asterion.

Background:The jugular foramen is difficult to understand and to access surgically, Its is difficult to conceptualize because it varies in size and shape in different crania, from side to side in the same cranium, from its intracranial to extra cranial end in the same foramen, because of its complex irregular shape, its curved course, its formation by two bones, and the numerous nerves and venous channels that pass through it. The morphometric measurements of the jugular foramen is very helpful in neurosurgery. Materials and Methods:A total of 500 jugular foramina were examined from 250 adult dry skulls. The present study was undertaken in adult south Indian skulls from different regions of south India, from different medical colleges. We have observed the length, width and area of the jugular foramina were determined. Metric measurements were taken by using Vernier calipers. The mean standard deviation and range of each dimension and derived index were computed. Right and left side differences were analysed.Results: In 71.2% of cases the right foramina were larger than the left, in 20.8% of cases the left foramina were larger than the right and in 8% cases they were equal in size on both sides. The mean length of the foramen on the right and left were 24.48+3.17mm and 21.24+4.51mm; the width measured 7.51+1.56mm and 7.16+1.89mm on the right and left respectively; the mean area on the right was 569.41+91.58cmm and on the left 470.40+115.45mm. Conclusion:There was statistical significance between the two sides in the length and area but there was no significant difference between the two sides in the width. There was a positive correlation between length and width on each side. Statistical analysis did show significant positive correlation between the width and length of the skull and the length of the jugular foramen on both sides.

Background:The jugular foramen is difficult to understand and to access surgically; the difficulties in exposing this foramen are created by its deep location and the surrounding structures, such as the carotid artery anteriorly, the facial nerve laterally, the hypoglossal nerve medially and the vertebral artery inferiorly, all of which block access to the foramen and require careful management. It is difficult to conceptualize because it varies in size and shape in different crania, between the two sides the same cranium, from its intracranial to extracranial end in the same foramen and because of its complex irregular shape, its curved course, its formation by two bones and the numerous nerves and venous channels that pass through it. The present study is concentrated to study morphological features of jugular foramen. Material and Methods:The present study was undertaken in 250(500 sides) adult south Indian skulls from different regions of south India, from different medical colleges. We have observed the size of foramen and presence of jugular fossa. Result:Out of 250 skulls in 20.8% of cases the right foramina were larger than the left, in 24.8% of cases the left foramina were larger than the right and in 8% cases were equal on both sides. The jugular fossa present bilaterally in 60%, on the right only in 21.6% cases, on the left only in 7.6% cases and was absent in 10.8% cases. Conclusion:The present study concludes that there is no significance different between size of foramen in right and left side. The jugular fossa or bulb present bilaterally in majority of cases.