Bilateral tripartite dural septation of the jugular foramen

Abstract

We present a case of bilateral tripartite dural septation on the internal aspect of the jugular foramen (JF) in a 71-year-old White South African male. Dura mater at the intracranial aspect of the JF forms the neurovascular compartment, which houses the cranial nerves (viz. glossopharyngeal (9th), vagus (10th), and accessory (11th) cranial nerves), as well as the jugular vein. In the present case, a dural septation was seen between the 9th and 10th cranial nerves and between the 10th and 11th cranial nerves; therefore, the 9th cranial nerve traversed the anterior compartment, the 10th cranial nerve traversed the intermediate compartment, and the 11th cranial nerve traversed the posterior compartment. Clinical implications of this variation of the JF arise due to the occurrence of glomus jugulare tumors, as well as other pathologies such as meningiomas and neuroinomas, and these tumors occur in the region in which the neurovasculature exits the cranium. The tumors then lead to compression of these structures within the foramen. Since two dural septa at the intracranial aperture of the JF are reported bilaterally, the rootlets of the cranial nerves were more tethered within the JF. This has surgical implications as substantial tethering of these rootlets requires additional dissection during surgery, thereby increasing the risk of iatrogenic injury to the cranial nerves. It has also been reported that compartmentalization of the JF accentuates the clinical presentation of the glomus jugulare tumor. Thus, a knowledge of variations within the JF becomes imperative to ENT and neurosurgeons.