Prevalence of Jugular Bulb Abnormalities and Resultant Inner Ear Dehiscence: a Histopathologic and Radiologic Study

Abstract

POSTERSMethod: A retrospective review was performed in patients undergoing canal wall reconstruction with postauricular twin flap and type I tympanoplasty after canal wall down from 2009 to 2010. Shape of the canal after reconstruction, pre-and postoperative audiogram, and postoperative complications such as infection, delayed healing, and dehiscence of the wall were evaluated.Results: Seven ears of 7 patients underwent the canal wall reconstruction procedure after canal down and type I tympanoplasty. The ages of the patients ranged from 19 to 63 years. The mean duration of follow-up was 13.3 months with a range of 9 to 18 months. The shape of the canal was maintained in all ears, and no dehiscence of the canal wall was found in all seven ears. Postoperative hearing was variable depending on the hearing of preoperation, but no worsening was observed. Mean improvement of postoperative air conduction was 21.8 dB, and that of postoperative air-bone gap was 16.4 dB. Conclusion:The postauricular twin flap is thin and flexible enough to support the posterior surface of the canal skin and to fill the space remaining after surgery. The twin flap procedure for the reconstruction of the external ear canal showed a high success rate.Objective: Jugular bulb (JB) abnormalities including high riding JB and JB diverticulum can erode inner ear structures and cause hearing loss, dizziness, and tinnitus. This study investigates 1) the prevalence of JB abnormalities, and 2) their erosion into inner ear structures using temporal bone histopathology and computed tomography (CT).Method: A total of 1579 temporal bones and 100 CT of the temporal bones (200 ears) were reviewed. The presence of a high JB was recorded as was its erosion into inner ear structures. Accompanying demographic and clinical information was reviewed.Results: High JB was noted in 8.2% (130/1579) of temporal bone specimens, and in 8.5% (17/200) of cases radiologically. Histologically, high JB were more common on the left side, in women, and in those greater than 40 years old. There was no significant increase in the prevalence of high JB over age 40 years. High JB eroded inner ear structures in 34% (44/130) of cases histologically and 18% (3/17) radiologically. The vestibular aqueduct was most frequently dehiscent histologically (n = 41) and radiologically (n = 3). Posterior semicircular canal and facial nerve were infrequently dehiscent. Only 2 out of 41 histological cases of vestibular aqueduct dehiscence had hydrops or a clinical history of Ménière's disease.Conclusion: JB abnormalities are common. They are present in 8% to 9% of individuals and are acquired by age 40 years. In 1/3 of cases, high riding JB erodes the inner ear, most frequently involving the vestibular aqueduct. Contrary to expectation, dehiscence of the vestibular aqueduct is infrequently associated with endolymphatic hydrops clinically or histologically.

Hydroxyapatite cement resurfacing the dehiscent jugular bulb: Novel treatment for pulsatile tinnitus

“…The prevalence of JB abnormalities increased with age, reaching 10% to 11% in the 41-to 60-year-old age range, with no difference in laterality or gender. 2 A larger series reviewing CT scans from 350 patients (700 temporal bones) found a higher incidence of both HJB and DHJB on the right (26.9% and 5.7%, respectively) compared to the left (13.7% and 2.0%, respectively). 3 Patients with these abnormalities have a variety of presentations, from being asymptomatic to reporting hearing loss, pulsatile tinnitus (PT), and vertigo.…”

“…Erosion into inner ear structures was present in 2.8% on histology and in 1.5% radiographically. The prevalence of JB abnormalities increased with age, reaching 10% to 11% in the 41‐ to 60‐year‐old age range, with no difference in laterality or gender . A larger series reviewing CT scans from 350 patients (700 temporal bones) found a higher incidence of both HJB and DHJB on the right (26.9% and 5.7%, respectively) compared to the left (13.7% and 2.0%, respectively) .…”

“…In early cadaveric temporal bone studies, an HJB was found to have a prevalence of 6% . In 2012, Friedmann et al studied cadaveric temporal bones and correlated clinical findings with computed tomography (CT) images . In this study, histology from 1,579 temporal bones were examined, and 100 CT scans of the temporal bones were reviewed.…”

“…1 In 2012, Friedmann et al studied cadaveric temporal bones and correlated clinical findings with computed tomography (CT) images. 2 In this study, histology from 1,579 temporal bones were examined, and 100 CT scans of the temporal bones were reviewed. High JBs were noted histologically in 8.5%, with an 8.2% incidence radiographically.…”

Endovascular treatment of jugular bulb diverticula causing debilitating pulsatile tinnitus

“…These are probably acquired lesions; the jugular bulb forms after 2 years, increasing in size to plateau in adulthood 8. The prevalence of jugular bulb abnormalities increases during the first four decades of life and stabilizes thereafter 9. While it is not possible accurately to identify what percentage of diverticula are symptomatic (and it is recognized that many will be asymptomatic6), they have been described in association with pulsatile tinnitus and other symptoms such as vertigo and hearing loss in a number of case series 1 2 6 10–12.…”