0
Case Report/Case Series |

Familial Superior Canal Dehiscence Syndrome

Marlien E. F. Niesten, MD1,2,3,4; Sarah Lookabaugh, MD4; Hugh Curtin, MD5; Saumil N. Merchant, MD†3,4; Michael J. McKenna, MD3,4; Wilko Grolman, MD, PhD1,2; Daniel J. Lee, MD3,4
[+] Author Affiliations
1Department of Otorhinolaryngology–Head and Neck Surgery, University Medical Center, Utrecht, the Netherlands
2Braincenter Rudolf Magnus, Utrecht, the Netherlands
3Department of Otology and Laryngology, Harvard Medical School, Boston, Massachusetts
4Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston
5Department of Radiology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston
JAMA Otolaryngol Head Neck Surg. 2014;140(4):363-368. doi:10.1001/jamaoto.2013.6718.
Text Size: A A A
Published online

Importance  The etiology of superior canal dehiscence (SCD) involving the arcuate eminence is not completely understood, but genetic factors may play a role. One hypothesis is that patients are born with a defect of the superior canal, and an acute event (such as head trauma) or progressive loss of bone (eg, due to dural pulsations) may result in the onset of SCD symptoms. Familial SCD has only been briefly mentioned in the literature to date.

Observations  We report 3 families that each had 2 members with SCD syndrome. We found that first-degree relatives presented with similar complaints and that temporal bone computed tomography scans between relatives showed very similar skull base topography and anatomic SCD defects.

Conclusions and Relevance  The presence of symptomatic SCD among first-degree relatives and similar skull base topography suggests that genetics may play a role in the etiology of SCD.

Figures in this Article

Sign In to Access Full Content

Don't have Access?

Register and get free email Table of Contents alerts, saved searches, PowerPoint downloads, CME quizzes, and more

Subscribe for full-text access to content from 1998 forward and a host of useful features

Activate your current subscription (AMA members and current subscribers)

Purchase Online Access to this article for 24 hours

Figures

Place holder to copy figure label and caption
Figure 1.
Audiometric Testing

A, Family 1, brother 1; B, family 1, brother 2; C, family 2, mother; D, family 2, daughter; E, family 3, mother; F, family 3, daughter. Despite similarities in symptom presentation, audiograms vary considerably between family members. Family 1 (A and B) has substantial air-bone gaps at all frequencies, but the magnitude of the air-bone gap differs. B also shows supranormal conduction (bone conduction of approximately −10 dB at 250 and 500 Hz), whereas A does not. Family 2 (C and D) has largely symmetric hearing loss in both relatives. However, C shows a moderate to severe mixed hearing loss, whereas D only shows a mild mixed hearing loss. Finally, family 3 (E and F) share little in common on audiogram. E shows air-bone gaps at all frequencies, whereas F does not show an air-bone gap. E also shows moderate hearing loss in the high frequencies (60 dB at 4 kHz and 65 dB at 8 kHz), whereas F shows normal hearing. AC indicates air conduction; ANSI, American National Standards Institute; BC, bone conduction; PTA, pure-tone average.

Graphic Jump Location
Place holder to copy figure label and caption
Figure 2.
Temporal Bone Computed Tomography (CT)

A and B, Family 1, brother 1; C and D, family 1, brother 2; E and F, family 2, mother; G and H, family 2, daughter; I and J, family 3, mother; K and L, family 3, daughter. All images are shown in Stenver view. For each individual, the image on the left is of the right ear (ie, A, C, E, G, I, K), and the image on the right is of the left ear (ie, B, D, F, H, J, L). In A and B, CT scan revealed defects of the medial arcuate eminence bilaterally (arrowheads) and well-aerated mastoids. Likewise, C and D show well-aerated mastoid bones and SCD defects in the same location as defects in A and B. Both brothers also had tegmen defects without dural herniation in the right ear (not shown). In E and F, the defects involve the peak of the arcuate eminence (arrowheads). The anatomic location of the defect in H is similar to that of the defect in F. Although G reveals a near-dehiscence on the right side, it is in the same location as the defect in E. Images E through H also reveal well-aerated mastoid bones. The temporal bones in all images for family 3 (I through L) show a severe downsloping tegmen that extends medially. These downsloping defects (arrowheads) have important surgical ramifications because intraoperative visualization of the defect can be difficult or impossible using binocular microscopy (and would necessitate excessive temporal lobe retraction). In such cases, we have found that a rigid angled endoscope is useful for direct visualization and repair of the entire bony defect via mini-craniotomy.11

Graphic Jump Location

Tables

References

Correspondence

CME
Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.
NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).
Submit a Comment

Multimedia

Some tools below are only available to our subscribers or users with an online account.

Sign In to Access Full Content

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Topics
Jobs
brightcove.createExperiences();