A Unique Ossified Variation of the Jugular Foramen.

The jugular foramen (JF) is one of the most complex skull base apertures. Recent studies have expanded knowledge on JF morphology, yet rare ossified variants remain underreported. We describe a unique case observed in a dry skull, where two complete ossified septa subdivided the right JF into three distinct compartments. Morphometric analysis revealed a large posterior venous compartment and two anterior neural compartments separated by a thin bony plate, representing the coexistence of a well-differentiated ossified jugular process and an ossified dural septum. Neurosurgically, such ossification narrows the JF lumen, complicates microneurosurgical exposure, and may predispose to selective cranial nerve compression or venous outflow compromise. High-resolution preoperative imaging, particularly CT with three-dimensional reconstruction, is therefore crucial for recognizing these rare anatomical variants to minimize intraoperative risk.