The blood supply to the canine middle ear

Abstract

Current descriptions of the anatomy of the blood supply to the canine middle ear are either incomplete or inconsistent, particularly in regards to the vascular branches in close proximity to the temporomandibular articulation (TMJ). To further investigate this blood supply, dissections (n 5 9), corrosion casts (n 5 4), and computed tomography (n 5 8) of canine temporal regions/ears were performed. The goal of this study was to identify and describe branches of the external carotid and maxillary arteries in close proximity to the TMJ that supply the middle ear of the dog. Specific focus was placed on the constancy and origin of the canine rostral tympanic artery since this artery was anticipated to arise from the maxillary artery and enter a foramen at the medial aspect of the mandibular fossa adjacent to the TMJ. New anatomical variations of three canine arteries are described in this study. (1) The rostral tympanic artery is a branch of the temporomandibular ramus and is accommodated by a small foramen located within a depression medial to the temporomandibular joint. (2) A pharyngeal branch of the caudal deep temporal artery was identified. (3) The origin of the caudal auricular artery occurred opposite the lingual artery in 25.8% of dissected specimens, contrary to published descriptions. Anat Rec, 299:907-917, 2016. V C 2016 Wiley Periodicals, Inc.Key words: rostral tympanic artery; caudal deep temporal artery branches; caudal auricular artery; dogThis research was an anatomically based and descriptive study that focused on those vessels supplying the canine middle ear. The canine middle ear blood supply has not been thoroughly described and there are some ambiguities in its description among authors and compared to other species. Branches of the maxillary artery supplying structures of the canine middle ear have been cited in anatomy texts (Ghoshal, 1975;Evans, 1993), but have not been thoroughly described. The rostral tympanic artery has been shown to be an important source of blood supply to the middle ear in the cat (Davis and Story, 1943); however, it is described as an inconstant branch of the canine maxillary artery (Ghoshal, 1975;Evans, 1993).It is well documented that branches of the external carotid and the maxillary arteries supply blood to the middle ear; therefore, dissections, corrosion casts, and CT scans performed in relation to this study focused on