Jugular diverticulum in the pars basilaris of the occipital bone: a rare case report.

Objective: Surgeons performing temporal bone-related procedures must be aware of vascular canal variations. These variations include high-rising jugular bulb, dehiscent jugular bulb, jugular bulb diverticulum and sigmoid sinus bulging. Jugular bulb is where lateral dural venous sinuses meet as they pass through jugular foramen. Two most common abnormalities of jugular bulb are a high-rising jugular bulb and a jugular bulb diverticulum. Etiology of these abnormalities is not fully understood. Jugular bulb diverticulum is an irregular extension of jugular bulb that extends into upper surface of petros part of temporal bone, tympanic cavity, endolymphatic duct, or tvestibular aqueduct. Abnormalities in this area may affect vestibular aqueduct, facial nerve, and posterior semicircular canal, which are located near jugular bulb. Case: 72-year-old woman presented to ENT outpatient clinic with complaints of dizziness that had persisted for one month. Upon examination, right geotropic horizontal nystagmus was detected. MRI of brain revealed bony defect in left pars basilaris of occipital bone, which was continuous with jugular bulb. Patient underwent brain CT angiography and brain CT venography examinations as specialists were still skeptical about mass. Findings supported jugular diverticulum. Clinical symptoms were determined to be unrelated to diverticula, and appearance was deemed incidental. Therefore, surgical intervention was not necessary. Patient's complaints improved after undergoing right apogeotropic gufoni application. Conclusion: We wanted to share this extremely rare variation that may be missed in MRI and CT reporting or confused with other pathologic conditions such as masses. Preoperative knowledge of the variations of vascular structures in temporal bone will guide physicians to prevent serious complications. [ABSTRACT FROM AUTHOR]