![]() ![]() More commonly, people have idiopathic contractions of the middle ear muscles. ![]() Many subjects can also voluntarily contract their middle muscles, particularly the TT by pharyngeal muscle contractions, although they may not realise this is what they are doing. In addition, forced eye closure can cause TT contraction and sounds in the ear. ![]() This can also occur with hemifacial spasm. ![]() In this syndrome, partial degeneration of the facial nerve results in aberrant regrowth of nerve fibres, with some fibres that would have gone to the facial muscles regrowing to the stapedius, causing stapedial contractions either heard as clicks or as hearing distortion with blinking or facial movements. Of true contractions of the MEMs, some are caused by synkinetic contractions of the stapedius muscle following a facial nerve paralysis. Other causes of clicking are from the TMJ joint, with opening and closing of the mouth, arising from degeneration of the articular disc, or arthritis of the joint. These can be sometimes helped with botox injections. This is associated with semi-rhythmic movements from the palate, and should be investigated with brain MRI as some are caused by lesions in the dento-rubro-olivary tract, although most are idiopathic. At other times, there may be rhythmic clicking sounds arising from the contractions of the palatine muscles that open and close the ET, from pathologies such as palatal myclonus or tremor. These kinds of sounds can be very bothersome to some patients, and may respond to grommets, which can be tested with a myringotomy. This may be normal, or arise because of enlarged adenoids abutting the nasopharyngeal opening and hitting the ET cushions, or from the mucous membranes/mucous film of the ET coming apart and back together during the swallowing-induced opening of the ET. One area is the Eustachian tube, and it is not uncommon for patients to have crackling with swallowing. Other rarer causes of noises in the ear are foreign bodies, such as hair on the eardrum, or even insects moving in the ear canal, assessed by otoscopy.Ĭrackles/noises/clicks can arise from many areas of the body. These have to be differentiated from pulsatile tinnitus, which is relatively easily done by asking the patient to beat out the noise rhythm with their finger while taking the patient’s pulse. Dynamic contractions presenting as clicks, crackles or noises in the ear repeated contractions, resulting in clicks or other sounds) and tonic contraction, resulting in fixed change in the length of the muscle and a sustained pull on the structures it attaches to. There are two types of symptom complexes that can arise from middle ear muscle dysfunction those from dynamic middle ear dysfunction (i.e. The TT does not seem to respond to sound in man, but has been reported to respond to face stroking, puffs of air against the eyes, electrical stimulation of the tongue and swallowing (reviewed by Bance et al ), it can also be voluntarily contracted by some people. Indeed, the TT is physically connected to the TVP muscle, and it can be difficult to separate if the originating pathology is in the TVP or the TT. The tensor tympani (TT) is supplied by the Vth nerve, as part of a system which also innervates the tensor veli palatini (TVP) and palatal muscles that open the eustachian tube. The stapedius muscle is supplied by the facial nerve. audiometric stapedial reflexes), it responds rather slowly for impulse noise, and has been also shown to respond to vocalisation. While the stapedius contracts in response to sound (e.g. The middle ear muscles (MEMs) are a mystery, both in their physiological function in man, and particularly in their pathophysiological contributions to symptoms when they malfunction. Prof Bance gives us an overview of the anatomy and function, as well as guides our diagnosis and management. Patients often report symptoms relating to disorders of the middle ear muscles. ![]()
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