====== Jugular Bulb ======

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The [[internal jugular vein]] begins in the posterior compartment of the [[jugular foramen]], at the [[skull base]].

It is somewhat dilated at its origin, and this dilatation is called the superior bulb.

It also has a common trunk that drains the anterior branch of the retromandibular vein, the facial vein, and the lingual vein.

It runs down the side of the neck in a vertical direction, being at one end lateral to the internal carotid artery, and then lateral to the common carotid, and at the root of the neck, it unites with the subclavian vein to form the brachiocephalic vein (innominate vein); a little above its termination is a second dilatation, the inferior bulb.

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CT: [[Chorda tympani]]; I: [[Incus]]; JB: [[Jugular bulb]]; LSC: [[Lateral semicircular canal]]; M: [[Malleus]]; PSC: [[Posterior semicircular canal]]; S: [[Stape]]s; SM: [[Stapedius muscle]]; SSC: [[Superior semicircular canal]]; VIIms: mastoid segment of [[VII cranial nerve]]; VIIts: tympanic segment of VII cranial nerve.

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AE: [[arcuate eminence]]; AICA: [[anteroinferior cerebellar artery]]; JB: [[jugular bulb]]; SC: [[semicircular canal]]s; SCA: [[superior cerebellar artery]]; SPV: [[superior petrosal vein]]; SS: [[sigmoid sinus]]; VA: [[vertebral artery]].
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Dehiscences of the intrapetrous canal of the facial nerve (FN) and those of a high jugular bulb (HJB) have various incidences. However, the HJB-FN common dehiscent osseous wall is a scarce finding and rarely reported. Thus, this work aimed to study this peculiar intrapetrous morphology on computed tomograms (CTs). A batch of 60 archived CTs was used. In 28.33% of cases, no HJBs were found; in 51.67% of cases, there were unilateral HJBs, and in 20% of cases, bilateral HJBs were found. 83.87% of the unilateral HJBs were on the right side, and the rest on the left side. In 3 cases with right-sided HJBs, 1 male and 2 females, FNs were found directly contacting the HJB. Therefore, the contact HJB-FN occurred in 5% of cases and 2.5% of the petrous bones/sides. HJBs' dehiscences to the retro tympanum or the posterior cranial fossa were also found in those cases. A dehiscent posterior semicircular canal to the HJB was found in one of these. Incidences for the HJB and the HJB-FN contacts seem higher than in previous studies. However, as only a 60-case batch of study was used, an overestimation may have resulted. Although scarce, the HJB-FN contact could determine specific symptoms and must be documented before surgical procedures involving the mastoid, retro tympanum, and posterior cranial fossa
((Rusu MC, Toader C, Tudose RC, Grigoriţă LO. When the Jugular Bulb Contacts the Facial Nerve. J Craniofac Surg. 2024 Nov 4. doi: 10.1097/SCS.0000000000010820. Epub ahead of print. PMID: 39495543.)).