Clinic Speak: MS-related hyperacusis

Have you ever had pain from hearing loud noises? Another MS related problem. #ClinicSpeak #MSBlog #MSResearch

"This is post is in response to a comment on hyperacusis in MS. A rare symptomatic problem in MS is hyperacusis, which refers to pain in response to hearing loud noises or specific sounds. The case series below is of three MSers who had different stimuli that generated hyperacusis. All these MSers had evidence of lesions affecting the auditory pathways in the brain-stem. In essence all these cases of hyperacusis represent a rare manifestation of a brain-stem relapse. Most symptoms associated with early relapses usually resolve as the lesion regresses. However, some MSers may be left with residual hyperacusis or intermittent hyperacusis when the damage pathway malfunctions due to fatigue or temperature-related changes. In my experience hyperacusis is more common in association with a so called facial nerve palsy; this occurs because a small muscle, called the stapedius muscle,  that tenses the ear drum is paralysed. The stapedius muscle tenses the ear drum as a reflex response to loud noises; by doing this it dampens the amount of sound that is transmitted to the inner ear to protect the sensitive hair cells from too much noise. Hyperacusis in the latter setting is easy to diagnose clinically it occurs in association with paralysis of the facial muscles on the side of the lesion. Facial muscle paralysis means you can't wrinkle your forehead, blow out your cheeks or smile. In this case it is relatively easy to diagnose."

"Hyperacusis is very difficult to treat in MS; you can either sit it out and wait for it to recover or you can  try different symptomatic therapies. There is some data suggesting that serotonin re-uptake inhibitors or SSRIs may help. If hypeacusis is intermittent you could try the usual drugs we use for over active nerves; gabapentin, pregabalin and sodium channel blockers (carbamazepine, oxcarbazepine, phenytoin, lamotrigine, etc.). If as in some of  the cases described below the hyperacusis is due to specific frequency you can get specialised acoustic lens or filters fitted that filter out sounds. These are specialist devices and need to be obtained through an audiologist."


Left facial palsy

"Should all MSers be investigated if they develop hyperacusis? Yes, there are other causes for this symptom and it is sufficiently rare in MS to warrant investigation to exclude other causes. How rare is it? I don't know but do you mind completing this short survey below to see? Thanks."


Weber et al. Central hyperacusis with phonophobia in multiple sclerosis. Mult Scler. 2002 Dec;8(6):505-9.

Background: Hearing disorders are a well-described symptom in MSers. Unilateral or bilateral hyperacusis or deafness in MSers with normal sound audiometry is often attributed to demyelinating lesions in the central auditory pathway. Less known in MS is a central phonophobia, whereby acoustic stimuli provoke unpleasant and painful paresthesia and lead to the corresponding avoidance behaviour.

Case studies: In our comparison collective, MSer 1 described acute shooting pain attacks in his right cheek each time set off by the ringing of the telephone. MSer 2 complained of intensified, unbearable noise sensations when hearing non-language acoustic stimuli. MSer 3 noticed hearing unpleasant echoes and disorders of the directional hearing. All MSers had a clinical brainstem syndrome. ENT inspection, sound audiometry and stapedius reflex were normal. All three MSers had pathologically changed auditory evoked potentials (AEPs) with indications of a brainstem lesion, and in magnetic resonance imaging (MRI) demyelinating lesions in the ipsilateral pons and in the central auditory pathway. The origin we presume in case 1 is an abnormal impulse conduction from the leminiscus lateralis to the central trigeminus pathway and, in the other cases, a disturbance in the central sensory modulation. All MSers developed in the further course a clinically definite MS. Having excluded peripheral causes for a hyperacusis, such as, e.g., an idiopathic facial nerve palsy or myasthenia gravis, one should always consider the possibility of MS in a case of central phonophobia. 

Conclusion: Therapeutic possibilities include the giving of serotonin reuptake inhibitors or acoustic lenses for clearly definable disturbing frequencies.

Labels: , , ,