Subarcuate canal and artery: a case report.

Variations in the course of the subarcuate artery (SAA) and of its related funnel are infrequent and asymptomatic. We present a case of a 15-year-old girl with a preverbal severe bilateral hearing loss and a subarcuate canal with an unusual course and atypical correlation with the adjacent anatomical structures, particularly with the lateral semicircular canal and the facial nerve. The variation proposed in this case, not previously reported in the literature consulted, can have important implications during middle ear surgical procedures, particularly for the retro-facial tympanoplasty approach: in fact otologic surgeons should consider any kind of variation of the SAA in surgical planning to avoid unexpected hemorrhages. The CT-scan, particularly HRCT, is a very useful tool for the study of intrapetrous vessels and their funnels, and should be considered mandatory in the case of a posterior approach to the tympanic cavity.