Foramen tympanicum with symptomatic temporomandibular joint herniation

Abstract

Foramen tympanicum (FT), or foramen of Huschke, describes an uncommon anatomicvariant of a persistent bony defect connecting the external acoustic meatus to the temporomandibular joint (TMJ). Although rare, it can be associated with significant complications, such as TMJ herniation, salivary gland fistula, infectious or tumoral spread between the external acoustic meatus and the TMJ, or result in inadvertent ear injury during TMJ arthroscopy. To the best of our knowledge, this is the first case report of a symptomatic FT with a full description of computed tomography and magnetic resonance imaging findings. Surgical exploration confirmed the presence of FT with TMJ herniation with subsequent successful closure of the defect obtained.

Keywords: Anatomic variation; External acoustic canal; Magnetic resonance imaging; Temporomandibular joint; X-ray computed tomography.

Fig. 1

Noncontrast computed tomography: (a) axial, (b) sagittal, and (c) coronal images, demonstrating a left foramen tympanicum forming a communication between the left temporomandibular joint and the anterior external acoustic meatus.

Fig. 2

Proton density weighted magnetic resonance images demonstrating temporomandibular joint herniation through the left foramen tympanicum. (a) Sagittal closed mouth and (b) sagittal open mouth images demonstrate a similar degree of temporomandibular joint herniation.