%0 Journal Article %T Superior canal dehiscence in a patient with three failed stapedectomy operations for otosclerosis: a case report %A Martin Lehmann %A J£¿rg Ebmeyer %A Tahwinder Upile %A Holger H Sudhoff %J Journal of Medical Case Reports %D 2011 %I BioMed Central %R 10.1186/1752-1947-5-47 %X We present the case of a 48-year-old German Caucasian woman presenting with hearing loss on the left side and vertigo. She had undergone three previous stapedectomies for hearing improvement. Reformatted high-resolution computed tomographic scanning and the patient's history confirmed the diagnosis of concurrent canal dehiscence syndrome.Failure of hearing improvement after otosclerosis surgery may indicate an alternative underlying diagnosis which should be explored by further appropriate evaluation.Superior semicircular canal dehiscence is an abnormal exposure of the vestibular membranous labyrinth in the middle cranial fossa. Superior semicircular canal dehiscence syndrome (SCD) occurs when a loss of the bone normally covering the superior semicircular canal in the middle cranial fossa produces one or more of the following symptoms: conductive hearing loss, acute pressure- and sound-evoked vestibular symptoms and chronic dysequilibrium [1]. The correlation between these symptoms and bony dehiscence of the superior semicircular canal in the floor of the middle cranial fossa was first recognized and described by Minor [2].We present the case of a 48-year-old German Caucasian woman who presented with hearing loss on the left side and vertigo. The patient had a history of three previous stapedectomy operations carried out elsewhere to improve her hearing loss (Figure 1). The first operation was performed for the diagnosis of otosclerosis. The next two operations were performed to improve her persistent hearing loss and vertigo.After the third operation, the patient came to our unit with persistent amblyacousia as well as severe vertigo and headache. Pure tone audiometry showed a maximal conductive hearing loss. The patient located in her left ear the sound of a tuning fork pressed on the right ankle. This phenomenon suggested SCD. Further high-resolution computed tomographic (CT) scans and audiometery were performed. A CT scan revealed superior semicircular canal deh %U http://www.jmedicalcasereports.com/content/5/1/47