Dehiscence of bone overlying the superior semi-circular canal was described in 1998 by Minor et al.  as a cause of sound and pressure induced vertigo. The condition of superior semicircular canal dehiscence has subsequently been the topic of numerous articles exploring the clinical presentation, investigation and management of the disorder. The incidence of dehiscent bone has been reported in cadaveric analysis to lie between 0.4 and 0.5%, with thinning of the bone to <0.1 mm in a further 1.4% .
Symptoms include one or more of the following: sound induced vertigo, often in a vertical-torsional plane; conductive hyperacusis; and chronic feelings of disequilibrium and motion intolerance . Clinical evaluation with a patient exposed to sound or pressure, wearing Frenzel's glasses, reveals nystagmus of an upward and anticlockwise nature in a right-sided lesion, and upward and clockwise in a left-sided lesion . Radiological imaging, with high resolution computed tomograms of the temporal bones, has a high sensitivity for the diagnosis of superior semicircular canal dehiscence but needs to be correlated with patient history, clinical examination and audiological and vestibular assessment to achieve a high specificity.
The treatment is either conservative, with the avoidance of causative stimuli, or surgical, if the symptoms are uncontrollable. Surgical repair or resurfacing of the dehiscence area of bone is the recommended interventional approach. There have, however, been many proposed approaches, materials and techniques. However, it is agreed that surgery can result in complete resolution of symptoms in most patients . The surgical technique has been described with various resurfacing methods including three- and five-layer techniques. This article describes a surgical approach using a five-layer technique for the repair of the dehiscence conducted in a district general hospital with complete resolution of symptoms and no detrimental effects on hearing and no long-term sequelae .