Slit-like jugular foramen due to abnormal bone growth at jugular fossa

The jugular foramen is a depression on the medial and inferior surface of the petrous pyramid formed by temporal and occipital bones [1,2]. It extends anteriorly, laterally and inferiorly from the endocranium to the exocranium between the temporal and occipital bones. The foramen is divided into two parts by a fibrous or osseous bridge that connects the jugular spine on petrous part of the temporal bone and the jugular process of the occipital bone. The foramen’s anteromedial compartment, the pars nervosa, contains the glossopharyngeal nerve and inferior petrosal sinus. The pars vascularis contains the jugular bulb and the vagus and spinal accessory nerves. The pars vascularis is usually larger on the right causing asymmetry of the jugular foramina [3]. The patients with lesions of the jugular foramen most commonly present with combinations of cranial nerve palsies (Vernet syndrome), which is characterized by loss of taste at the posterior third of the tongue (cranial nerve IX); vocal cord paralysis and dysphasia (cranial nerve X); and weakness of sternocleidomastoid and trapezius (cranial nerve XI) [4].