top of page

BackTable / ENT / Article

Causes of Sudden Sensorineural Hearing Loss (SSHL): Many Potential Etiologies, One Otologic Emergency

Author Julia Casazza covers Causes of Sudden Sensorineural Hearing Loss (SSHL): Many Potential Etiologies, One Otologic Emergency on BackTable ENT

Julia Casazza • Oct 9, 2023 • 69 hits

Sudden sensorineural hearing loss (SSHL) can result form vascular, infectious, congenital, neoplastic, toxic, and traumatic etiologies, though 90% of cases are idiopathic. Otologist Dr. Sujana Chandrashekar recently sat down with BackTable to discuss the potential causes of sudden sensorineural hearing loss. While most patients can receive steroids to restore their hearing, rarer etiologies of SSHL may mandate additional treatments. In some cases, SSHL can be the presenting symptom of a vestibular schwannoma, Lyme disease, or syphilis. For this reason, systematic workup of SSHL is important.

This article features excerpts from the BackTable ENT Podcast. We’ve provided the highlight reel in this article, and you can listen to the full podcast below.

The BackTable ENT Brief

• All patients with suspected sudden sensorineural hearing loss (SSHL) need an audiogram within 14 days of symptom onset.

• Infectious diseases, including herpes zoster and syphilis, can cause SSHL when infection extends to the ear.

• Patients with low-frequency hearing loss have a better prognosis than those with high-frequency losses.

• All patients with SSHL require a retrocochlear workup to rule out vestibular schwannoma. MRI of the internal auditory canal is the best imaging for this purpose, but CT temporal bone with contrast is appropriate for those unable to undergo MRI.

• 90% of SSHL cases are idiopathic. Other etiologies of SSHL include stroke, infections, trauma, meniere’s disease/cochlear hydrops, and congenital disease.

Causes of Sudden Sensorineural Hearing Loss (SSHL): Many Potential Etiologies, One Otologic Emergency

Table of Contents

(1) Workup of Suspected Sudden Sensorineural Hearing Loss

(2) Audiogram Findings as Prognostic Indicators

(3) Causes of Sudden Sensorineural Hearing Loss

Workup of Suspected Sudden Sensorineural Hearing Loss

While the treatment of sudden sensorineural hearing loss usually includes steroids, exceptions, based on disease origin, exist. Therefore, workup of suspected SSHL should investigate multiple causes of hearing loss. On physical exam, pay attention to otalgia and vesicular lesions – both of which should clue the clinician into an underlying herpes zoster oticus infection, which is treated with antivirals. When patient history raises suspicion for otosyphilis or Lyme disease, appropriate diagnostics should be ordered, as treatment of either infection can restore hearing. All patients with suspected SSHL need an audiogram within 14 days of initial hearing loss. As most SSHL patients lack a premorbid audiogram, testing both ears allows clinicians to use the unaffected ear as a “control.”

[Dr. Ashley Agan]
Before we get into treatment, your physical exam, in my experience it's pretty normal. You're looking in the ear and they're like, are you sure? Are you sure there's not something there? You're like, ah, it looks normal. Then with your audiogram too, is there any patterns on the audiogram that change what you're thinking about whether it be a low frequency loss versus mid-range versus high frequency?

[Dr. Sujana Chandrashekhar]
For your physical exam, I will just add it's a patient has any complaints of otalgia and that's really different. Very few people with sudden hearing loss will tell you that their ear hurts, but really have a low threshold for looking for erythema or healing vesicles either in the canal or on the pinna. Obviously you're going to look for facial palsy, like oh my god, if you're missing a facial palsy and these people, I'm going to be really sad. That's going to throw you in a different direction. Look for blebs on the TM, so there are viral exams that happen where you have these blebs on the TM that are also associated with sudden hearing loss.

Your treatment may end up being the same for the sensorineural component of the hearing loss, but you may actually puncture the lateral surface of the bleb under a microscope and then put some boric acid powder on there to resolve that portion of it. I shockingly saw a patient who came after being admitted to a university hospital and being seen by staff there and residents there with a roaring herpes zoster oticus and I'm like, "What? Somehow that was missed." I don't think anyone is dumb. I think what happens is you get sidetracked by where you think you're going, and you don't step back and see where you are. I think that's really important in life and I think that's really important in medicine.

For your physical exam, I think those things are very important. We talked initially about conductive hearing losses and if you see fluid in the ear, you really have to be cognizant of that. A tympanogram, which we didn't mention, may help you with that, but you should be able to be what at Pittsburgh they used to call a validated otoscopist where you got it right over 90% of the time if you felt there was or was not fluid in the middle year, when the patient went to the OR was there fluid or not? I've never been validated at Pittsburgh.

[Dr. Ashley Agan]
90% is high.

[Dr. Sujana Chandrashekhar]
It's really high, right? I'm always playing that trick with myself to see what I see and what I don't see. I think that's really crucial for your own particular CME and assessments of your own.

Listen to the Full Podcast

Sudden Sensorineural Hearing Loss with Dr. Sujana Chandrasekhar on the BackTable ENT Podcast)
Ep 87 Sudden Sensorineural Hearing Loss with Dr. Sujana Chandrasekhar
00:00 / 01:04

Earn CME

BackTable CMEfy button

Stay Up To Date

Follow:

Subscribe:

Sign Up:

Audiogram Findings as Prognostic Indicators

Audiometric findings represent important prognostic indicators for SSHL. Low-frequency losses, or “upsloping” patterns, usually self-resolve, and treatment is less urgent. High-frequency losses, or “downsloping” patterns, tend not to recover, and more aggressive management is indicated. Dr. Chandrashekar recommends following patients with high-frequency losses for a year after initial presentation,as up to 30% of them will present with Meniere’s Disease or cochlear hydrops within that time frame.

[Dr. Ashley Agan]
Then about patterns on the audiogram. If you have a patient that-- it's predominantly a low-frequency loss, are you thinking that this could be Meniere's or cochlear hydrops and maybe their first episode versus if it's mid-range or high frequency and what your thoughts are with looking at those patterns.

[Dr. Sujana Chandrashekhar]
I think that's really important. We talked about pure tones, we talked about proper masking to get proper thresholds, we talked about word discrimination. Certainly, we can talk about tympanograms to help you validate yourself, but the shape of the audiogram is really important. Low frequency also called up-sloping audiograms, first, they tend to recover almost if you do whatever you do. Go tell the patient to stand on their head for a week, give them some steroids, give them some diuretics, tell them to stop eating salty foods whatever, they tend to recover. If they don't recover, that's really quite meaningful to me because these tend to recover.

The sloping or down-sloping or high-frequency hearing losses tend not to recover. I possibly am at least mentally more aggressive with those patients in terms of treatment, I don't know if I'm actually more aggressive. I think I'm pretty aggressive with treating sudden hearing loss. I'm very Pollyanna. I very much believe that I can help recover hearing loss. I do discuss that particular implicit bias in myself with the patients because it's very important that they know where their doctor is starting. The high frequencies tend not to recover. I'm pretty aggressive about those. The pan-tonal which is all frequencies can be mild, moderate, severe, or profound.

In those, the low frequencies have a tendency to recover faster and possibly better than the higher frequency. The low and mids tend to recover, but the highs can recover doesn't mean the highs can't recover, it means you just have to be cognizant that they can take their own sweet time a little bit. In the pan-tonal you're really looking at the severity across frequencies. Nora Penido, who is at the Universidade Federal de São Paulo in Brazil in Sao Paulo, she published looking a year later at her patients who presented with sudden hearing loss and 30% ultimately showed as Meniere's or cochlear hydrops so you really do have to follow these patients over time.

Causes of Sudden Sensorineural Hearing Loss

Approximately 9 in 10 cases of SSHL are idiopathic. The 10% with identifiable causes are due to tumors (including vestibular schwannoma), strokes, infections, ototoxic medications, perilymphatic fistula, and congenital causes. A history of head trauma should raise suspicion for perilymphatic fistula.

[Dr. Ashley Agan]
Then about patterns on the audiogram. If you have a patient that-- it's predominantly a low-frequency loss, are you thinking that this could be Meniere's or cochlear hydrops and maybe their first episode versus if it's mid-range or high frequency and what your thoughts are with looking at those patterns.

[Dr. Sujana Chandrashekhar]
I think that's really important. We talked about pure tones, we talked about proper masking to get proper thresholds, we talked about word discrimination. Certainly, we can talk about tympanograms to help you validate yourself, but the shape of the audiogram is really important. Low frequency also called up-sloping audiograms, first, they tend to recover almost if you do whatever you do. Go tell the patient to stand on their head for a week, give them some steroids, give them some diuretics, tell them to stop eating salty foods whatever, they tend to recover. If they don't recover, that's really quite meaningful to me because these tend to recover.

The sloping or down-sloping or high-frequency hearing losses tend not to recover. I possibly am at least mentally more aggressive with those patients in terms of treatment, I don't know if I'm actually more aggressive. I think I'm pretty aggressive with treating sudden hearing loss. I'm very Pollyanna. I very much believe that I can help recover hearing loss. I do discuss that particular implicit bias in myself with the patients because it's very important that they know where their doctor is starting. The high frequencies tend not to recover. I'm pretty aggressive about those. The pan-tonal which is all frequencies can be mild, moderate, severe, or profound.

In those, the low frequencies have a tendency to recover faster and possibly better than the higher frequency. The low and mids tend to recover, but the highs can recover doesn't mean the highs can't recover, it means you just have to be cognizant that they can take their own sweet time a little bit. In the pan-tonal you're really looking at the severity across frequencies. Nora Penido, who is at the Universidade Federal de São Paulo in Brazil in Sao Paulo, she published looking a year later at her patients who presented with sudden hearing loss and 30% ultimately showed as Meniere's or cochlear hydrops so you really do have to follow these patients over time.

In a society with less mobility, it's easier to follow patients over time. Frankly, in private practice, it's easier to follow patients over time than it is in a more mobile society, a clinic practice, or somewhere where access to healthcare comes and goes. I think you really have to think about Meniere's as a potential cause that can only be determined sometime later in these patients and you do have to keep following them.


Podcast Contributors

Dr. Sujana Chandrasekhar discusses Sudden Sensorineural Hearing Loss on the BackTable 87 Podcast

Dr. Sujana Chandrasekhar

Dr. Sujana Chandrasekhar is an otologist / neurotologist practicing at ENT and Allergy Associates in New York City.

Dr. Ashley Agan discusses Sudden Sensorineural Hearing Loss on the BackTable 87 Podcast

Dr. Ashley Agan

Dr. Ashley Agan is a practicing ENT and assistant professor at UT Southwestern Medical Center in Dallas, TX.

Dr. Gopi Shah discusses Sudden Sensorineural Hearing Loss on the BackTable 87 Podcast

Dr. Gopi Shah

Dr. Gopi Shah is a practicing ENT at UT Southwestern Medical Center in Dallas, TX.

Cite This Podcast

BackTable, LLC (Producer). (2023, January 31). Ep. 87 – Sudden Sensorineural Hearing Loss [Audio podcast]. Retrieved from https://www.backtable.com

Disclaimer: The Materials available on BackTable.com are for informational and educational purposes only and are not a substitute for the professional judgment of a healthcare professional in diagnosing and treating patients. The opinions expressed by participants of the BackTable Podcast belong solely to the participants, and do not necessarily reflect the views of BackTable.

backtable-earn-free-cme.jpg
backtable-plus-vi-cta.jpg

Podcasts

Sudden Sensorineural Hearing Loss with Dr. Sujana Chandrasekhar on the BackTable ENT Podcast)

Articles

Sudden Sensorineural Hearing Loss Treatment

Sudden Sensorineural Hearing Loss Treatment

Evaluating Sudden Sensorineural Hearing Loss (SSHL) Symptoms

Evaluating Sudden Sensorineural Hearing Loss (SSHL) Symptoms

Topics

Learn about Otology on BackTable ENT

Get in touch!

We want to hear from you. Let us know if you’re interested in partnering with BackTable as a Podcast guest, a sponsor, or as a member of the BackTable Team.

Select which show(s) you would like to subscribe to:

Thanks! Message sent.

bottom of page