1. Tianbo Ren M.D. Ajay Malhotra M.D. Yale University School of Medicine Control Number: 1948 Abstract Number: EP-96

2. None of the authors have any conflicts of interest

4.  Aberrant jugular bulb is a common incidental finding on temporal bone CT studies  Cases of aberrant jugular bulb has been associated with hearing loss, as well as vestibular canal dehiscence  We seek to evaluate whether there is also an association with osseus adhesion between the aberrant jugular bulb and the ossicles, and whether this may contribute toward hearing loss

5.  Also known as “high riding jugular bulb”  Occurs more often on right side  Have been associated with:  Hearing Loss  Vertigo  Tinnitus  Intra-op bleeding High riding RIGHT jugular bulb bulging into the middle ear cavity Upper margin of a normal LEFT jugular bulb

6.  Vestibular aqueduct dehiscence (VAD) in the presence of aberrant jugular bulb (AJB) have been seen in patients suffering hearing loss  Kupfer et. al. Otolaryngol Head Neck Surg, 2012  VAD/AJB seen in 8.3% of patients with hearing loss  VAD/AJB seen in 7.1% of patients without hearing loss  Hourani et. al. J Comput Assist Tomogr, 2005  11.5% of patients had both AJB and VAD  47.8% of these patients had hearing loss  However, neither study showed a significant correlation between VAD/AJB and hearing loss

7.  In the presence of aberrant jugular bulb, osseus adhesion has been observed between the high riding jugular bulb and the ossicular chain  Can such osseus adhesion within the middle ear cavity be associated with hearing loss?

9.  Retrospective analysis on patients who underwent high resolution head CT or temporal bone CT at Yale New Haven Hospital, and whose reports mentioned the jugular bulb  2 readers evaluated each case to determine whether there is presence of vestibular aqueduct dehiscence and/or osseus adhesion between the jugular bulb and the ossicles  For those patients who exhibit osseus adhesion, their electronic medical record charts were evaluated to determine if they suffer from hearing loss

10. Total starting patients: 70 Total excluded patients: 17 14 subjects did not have aberrant jugular bulbs 3 subjects’ ossicles were eroded/not visualized Total number of subjects evaluated: 53 Subject sex and age breakdown: Age GroupMaleFemale 0-1584 16-3035 31-4557 46-60410 >6025 Total2231

12.  53 subjects all exhibit aberrant jugular bulb  16/53 (30.2%) exhibited vestibular aqueduct dehiscence  3/53 (5.7%) exhibited osseus adhesion between the jugular bulb and ossicles  1 of the 3 patients with osseus adhesion has a history of conductive hearing loss

13. Malleus Aberrant jugular bulb Osseus Adhesion

15.  3 out of 53 subjects evaluated in this study exhibited concomitant aberrant jugular bulb and osseus adhesion between the jugular bulb and ossicles, with 1 of the 3 subjects affected by hearing loss.  These findings suggest an additional possible mechanism for the development of hearing loss in patients who have aberrant jugular bulbs.  Incidence of osseus adhesion (3/53) seem lower than that of vestibular aqueduct dehiscence (16/53). As no large scale studies have been performed to evaluate osseus adhesion, further study using a larger sample size may prove beneficial.

16. Chennupati SK, Reddy NP, O’Reilly RC. High-riding jugular bulb presenting as conductive hearing loss. International Journal of Pediatric Otorhinolaryngology Extra.6(4):235-237. Friedmann DR, Le BT, Pramanik BK, Lalwani AK. Clinical spectrum of patients with erosion of the inner ear by jugular bulb abnormalities. The Laryngoscope. 2010;120(2):365-372. Hourani R, Carey J, Yousem DM. Dehiscence of the Jugular Bulb and Vestibular Aqueduct: Findings on 200 Consecutive Temporal Bone Computed Tomography Scans. Journal of Computer Assisted Tomography. 2005;29(5):657-662. Kupfer RA, Hoesli RC, Green GE, Thorne MC. The relationship between jugular bulb-vestibular aqueduct dehiscence and hearing loss in pediatric patients. Otolaryngol Head Neck Surg 2012;146(3):473-477. Saito T, K. L, H. S. High jugular bulb adhering to the eardrum. Annals of otology, rhinology & laryngology. 06 1999;108(6):620- 622. Weiss RL, G. Z, E. G, H. P, J. SM. High jugular bulb and conductive hearing loss. The Laryngoscope. 03 1997;107(3):321-327.

17. Tianbo Ren M.D.  tianbo.ren@yale.edu tianbo.ren@yale.edu  Yale University School of Medicine 333 Cedar Street (Room CB-30) PO Box 208042 New Haven, CT 06520-8042