European Archives of Oto-Rhino-Laryngology

, Volume 269, Issue 2, pp 475-480

First online:

Semicircular canal dehiscence in HR multislice computed tomography: distribution, frequency, and clinical relevance

  • H. StimmerAffiliated withInstitut für Radiologie, Klinikum r. d. Isar, TU München Email author 
  • , K. F. HamannAffiliated withHNO-Klinik, Klinikum r. d. Isar, TU München
  • , S. ZeiterAffiliated withInstitut für Radiologie, Klinikum r. d. Isar, TU München
  • , A. NaumannAffiliated withInstitut für Medizinische Statistik und Epidemiologie, Klinikum r.d. Isar TU München
  • , E. J. RummenyAffiliated withInstitut für Radiologie, Klinikum r. d. Isar, TU München

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


The literature about bony defects in the semicircular canal system is highly inconsistent. Therefore, we analyzed a series of 700 high-resolution multislice CT examinations of the temporal bone for semicircular canal dehiscencies. An unselected group of ENT patients with different clinical symptoms and variable age was chosen. We found semicircular canal dehiscence in 9.6% of temporal bones, superior semicircular canal was affected mostly (8%), less common posterior semicircular canal (1.2%); only in 3 cases (0.4%), lateral semicircular canal showed dehiscence. In 60% of SSC dehiscence, we registered bilateral manifestation. The so-called “third mobile window” in semicircular canal dehiscence causes a great variety of clinical symptoms like vertigo, nystagmus, oscillopsies, hearing loss, tinnitus and autophonia. Comparison with anatomic studies shows that CT examination implies the risk of considerable overestimation; this fact emphasizes the important role of clinical and neurophysiological testing.


Semicircular canal dehiscence HR computed tomography Perilymph Vertigo Tullio phenomenon