Sudden Hearing Loss (SSNHL)

What Is Sudden Sensorineural Hearing Loss (SSNHL)?

To suddenly lose your hearing can be a very frightening and worrying experience.

Hearing loss for most people is a gradual progression, but if hearing loss occurs in a very a sudden or very rapid manner (in one or both ears) then you may have a condition called ‘Sudden Sensorineural Hearing Loss’ (SSNHL).

This is a serious condition that can affect anyone of any age regardless of any previous hearing issues and needs to be treated as a medical emergency.

As the name suggests, it is a sudden drop in hearing (within 12 hours or less). Some people notice a ‘pop’ or a blocked ear before their hearing drops, or it can deteriorate noticeably and very quickly. It is not uncommon to wake up to the condition. The most common SSNHL causes are idiopathic in nature; meaning that they occur for no particular reason.

What Are Some SSNHL Symptoms?

Symptoms of sudden hearing loss would include:

Sudden loss of hearing in the affected ear
A sensation of ear blockage or fullness
A ringing sound in the ear (tinnitus)
Dizziness and a sensation of the room spinning (vertigo)

What Should I Do If I Think I Have Sudden Hearing Loss?

The key thing is to recognise your abnormal hearing and seek urgent medical care from an ENT specialist.

The difficulty with this condition is that it is invisible to most doctors and you may have no other except an ear complaint. This condition cannot be detected by a physical ear examination although this can rule out other complications like ear infection or ear wax as the cause of hearing loss. Some patients may also experience vertigo (dizziness) or tinnitus as well as hearing loss. Hearing loss may be a temporary outcome of this condition, but if left untreated it can be permanent.

A hearing test (audiogram) is required to make the diagnosis and assess the degree and severity of the hearing loss. Steroid treatment within 24-48 hours of onset is ideal, and acting quickly is crucial.

What Is The Treatment For Sudden Sensorineural Hearing Loss?

The mainstay of common treatment is prompt treatment and early initiation of steroids unless contraindicated. The use of steroids should be tailored to the individual patient; co-morbidities or risk factors taken into account and potential side effects of steroids discussed with the patient. Even in diabetic patients, the individual risk-benefit analysis usually favors steroid use, with appropriate monitoring and management of diabetes.

Hence, SSNHL treatment is a course of high dose oral steroids, or sometimes steroid injections directly into the middle ear through the eardrum, or both concurrently. Getting treatment very quickly after the onset of symptoms is crucial to improving the chances of restoring hearing, ideally within 48 hours or less.

Rapid and timely administration of steroids help in reducing inflammation and may potentially restore hearing.

Are There Guidelines For Treatment?

Treatment with oral steroids is usually between 7–14 days, and tapering is not required with shorter courses. Studies have not shown a conclusive benefit; however, oral steroids have been recommended in recent guidelines as the standard treatment for this condition.

The SSNHL treatment guidelines suggest the use of intratympanic steroid injections should this initial therapy fail, as it may offer some hope as a salvage treatment if the response to systemic steroids is poor. Patients who do not respond to oral steroids should be referred early for consideration of intratympanic steroids. There may be a role for hyperbaric oxygen therapy, but the evidence for this is not strong at this point in time. There is also no compelling evidence for the use of other therapies, such as carbogen, vasodilators or thrombolytics.

Can You Recover From Sudden Hearing Loss?

Indicators of a better prognosis include:

Low frequency hearing loss
A less severe level of hearing loss at presentation
Early commencement of treatment

Indicators of a worse prognosis with permanent hearing loss include:

Patients aged less than 15 years
Patients aged more than 60 years
Patients with concurrent symptoms of vertigo

Patients with permanent hearing loss may require hearing aids to improve hearing and quality of life.

What Is SSNHL Recovery Time Like?

Patients with a more severe level of hearing loss appear to respond better to steroid therapy. Between one- and two-thirds of patients will recover some hearing within 2 weeks of onset. It is also possible that improvements may reflect a degree of spontaneous improvement rather than a true response to therapy.

How Did I Get This Condition?

The causes of this condition are not fully understood. This condition can occur after major head trauma, virus infection, blood circulation issues or as a result of an autoimmune condition and problems with the immune system. Sometimes further investigation is warranted either by MRI scan or CT scan; as well as blood tests but most often no identifiable cause of is found. This is termed idiopathic SSNHL.

References:

Harvard Health | Sudden Hearing Loss

National Institute Of Health | Sudden Deafness