Structure of the middle ear and auditory tube in the house musk shrew, Suncus murinus.
Anatomical features of the middle ear and auditory tube (AT) in the house musk shrew, Suncus murinus, were examined by dissection and light microscopy. The tensor veli palatini (TVP) and tensor tympani (TT) have no connections with the wall or cartilage of the AT although they are connected by the intermediate tendon. None of the levator veli palatini (LVP) muscle bundles are attached to the AT. The salpingopharyngeus (SA) alone has its origin on the caudal edge of the tubal cartilage. The origin extends to the pharyngeal two thirds of the cartilage. The SA originates perpendicular to the AT and runs caudomedialward. Some SA muscle bundles intermingle with those of the palatopharyngeus to end on the dorsal wall of the pharynx. The observations provide no evidence that the TVP, LVP and TT have any role in AT function. The only muscle affecting the AT function in S. murinus is the SA, and it would be the AT dilator.
Yoshida
M
M
Department of Otorhinolaryngology, Aichiken Saiseikai Hospital, Nagoya University School of Medicine, Nagoya, Japan.
Kitoh
J
J
Yanagita
N
N
D000818:Animals; D002814:Chorda Tympani Nerve / Q000033:anatomy & histology; D004432:Ear, Middle / Q000033:anatomy & histology* / Q000294:innervation; D005064:Eustachian Tube / Q000033:anatomy & histology* / Q000294:innervation; D005260:Female; D008297:Male; D009132:Muscles / Q000033:anatomy & histology; D012788:Shrews / Q000033:anatomy & histology*