Morphometric study of Jugular Foramen at base of the skull in South Gujarat region

The jugular foramen is the main route of venous outflow from the skull and is characterised by laterality based on the predominance of one of the sides. Intracranial meningiomas, paragangliomas (glomus jugulare, from the jugular ganglion of the vagus nerve), schwannomas, metastatic lesions and infiltrative inflammatory processes from surrounding structures such as the middle ear may affect the structures passing through this foramen. We studied one hundred dry, adult human skull of unknown sex and measured sagittal and transverse diameter of Jugular foramen. Jugular foramen were also observed for the presence of dome, septation and right or left dominance. Mean transverse diameter of jugular foramen was 11.61mm and mean sagittal diameter was 7.12mm.The size of the jugular foramen varied on the two sides. R>L were 75%, R<L were 31%, R=L were 2%.The jugular bulb dome was present bilaterally in 23%, on the right side only in 30%, on the left side only in 11%, and absent in 36%.Complete septation was present in 16% on the right side and 14% on the left side. Partial separation was present in 29% on the right side and in 25% on the left side. Knowledge of morphology, compartments and morphometry is important for neurosurgeons dealing with space occupying lesions in jugular foramen.