Dehiscence of the superior semicircular canal: a review of the literature on its possible pathogenic explanations

Abstract

The dehiscence of superior semicircular canal is a well-known affection which is able to explain some cases of hearing loss, tinnitus and/or vertigo unexpectedly presenting in adults without previous otologic affections. Although a diagnostic algorithm has been assessed and a surgical therapy has been indicated, the review of the literature shows that a completely satisfactory explanation for the reason why symptoms of a supposed congenital condition only occur in adulthood is still lacking. A pathogenic hypothesis based on the slow metabolism of the bony labyrinth, which could in time result in a prevalence of bone re-absorption on new bone formation leading to a dehiscence, despite some controversial findings could represent a the most reliable explanation for the question.

Radiological prevalence of superior and posterior semicircular canal dehiscence in children

“…There were no cases of lateral canal dehiscence in our series. Two previous case reports have noted dehiscence associated with other inner ear abnormalities [3,24] but none of the prevalence studies have looked at this in detail.…”

“…Some authors advocate a congenital predisposition, which may subsequently lead to symptomatic clinical disease in adulthood, whilst others propose that intact bone in childhood is later thinned by osteopenic processes [2,3] or microtrauma [4].…”

Hyperacusis as a Symptom of Superior Semicircular Canal Dehiscence

“…6 Actual disruption of the abnormally thin layer of bone often occurs following a traumatic event or pressure from the temporal lobe or dura or may be due to the aging process. [6][7][8] There is great variability in the presentation of symptoms between individuals. Patients may report vertigo or oscillopsia that occurs in the presence of loud sound or pressure changes.…”

Comparison of radiologically and histologically determined thickness of bone overlying the superior semicircular canal in sixty‐six cadaveric specimens: impact on the diagnosis of Minor's Syndrome

“…The syndrome of superior canal dehiscence (SCD) was first described by Minor and colleagues in 1998 and has been a much‐discussed topic in otology since . The clinical manifestations of SCD usually include sound or pressure related symptoms of vertigo and disequilibrium .…”

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The syndrome of superior canal dehiscence (SCD) was first described by Minor and colleagues in 1998 1 and has been a much-discussed topic in otology since. [2][3][4] The clinical manifestations of SCD usually include sound or pressure related symptoms of vertigo and disequilibrium. 5 Patients often describe an increased sensitivity to internal sounds such as pulsatile tinnitus or joint and muscle movements including hearing themselves blink.

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