TRANS-TYMPANIC DEXAMETHASONE INJECTION
The Trans-Tympanic (TT) Dexamethasone Injection (UK) or Intra-Tympanic (IT) Dexamethasone Injection (American), is one of the methods to help improve hearing, usually after an attack of Sudden Sensorineural Hearing Loss (SSNHL).
What is a TT or IT Dexa injection?
During a TT or IT Dexa injection, the steroid Dexamethasone is injected through the tympanic membrane into the middle ear space. The medication is then absorbed via the round window into the inner ear.
Steroid treatment has been shown to help reduce tinnitus, reduce loss of balance, restore hearing loss, and improve speech discrimination in hearing (add links to webpages for mentioned conditions) over a period of time.
Steroids are well known for their strong anti-inflammatory effect on the human body. Administering steroids within the critical 2-week window period can help reduce inflammation in the inner ear, and potentially rescue hearing ability following a sudden hearing loss incident.
TT or IT Dexa is the localized injection of steroids, directly into the middle ear space. The dosage of the steroid injection (4mg) is lower than when compared to oral steroid tablets (60mg). The location-specific delivery means that an injection can administer a lower dosage, with a lower risk of side effects, while still being effective at treatment.
Photo of Dexamethasone steroid that is injected into the inner ear
This makes TT or IT Dexa ideal for patients who cannot tolerate high-dose oral steroids, such as diabetic patients. High-dose oral steroids usually affect blood sugar control adversely and may require adjustment of the patient’s other medications, such as insulin.
Early incident reporting and treatment
TT or IT Dexa injections are most effective at reversing a hearing loss, ideally within 2 weeks, and up to a month after a sudden hearing loss incident. Beyond this period, there is a lower chance of success for a steroid rescue of hearing. Therefore, it is best to seek treatment immediately following a sudden hearing loss incident, and the earlier the better.
You may wish to keep a record of when specifically, your drop in hearing began, as well as any other further sudden hearing loss incidents to accurately relay the details of what happened to the doctor during your appointment. It is best also to include any associated instances of tinnitus, vertigo or dizziness as it may be related to the hearing loss.
Before the TT or IT Dexa injection (Hearing test & MRI Scan)
The assessment of sudden hearing loss includes hearing tests with an audiologist to determine the degree and extent of your hearing loss. Based on these results, the doctor can advise if the TT or IT Dexa Injection is recommended.
The doctor will most often also advise undertaking an MRI Scan of the inner ear & nerves before recommending the TT or IT Dexa injections. This MRI scan is to rule out the possibility of there being any growths (neuroma/fibroma) on the hearing and balance nerves that are causing the hearing loss. If there is growth, then the administered steroids will NOT rescue your hearing loss and you may require other forms of treatments or operations.
The duration of the whole procedure, including the rest period, is about roughly an hour. The injection can be done as a day surgery procedure in the clinic.
After the procedure, patients are to lie down and rest to allow the medication to be adequately absorbed and spread through the inner ear fluids. Patients are also advised NOT to swallow after the injection for at least 30 minutes.
This is to prevent the medication from flowing down the eustachian tube into the throat, rendering the treatment ineffective.
Please do not drive following the injection in case of giddiness. If required, please make alternative transport arrangements, or have someone accompany you home after the procedure.
After the procedure, patients are asked to perform follow-up hearing tests to compare results and determine the effectiveness of the injection. This will allow the doctor to determine if additional injections are necessary.
Repeat injection efficacy
Repeated injections can increase the chances of hearing recovery in some cases. However, the results of repeated injections will vary from individual to individual. If the hearing loss shows no signs of improvement after the first or second injections, the doctor will not usually recommend any further injections.
Potential side effects and risks
Temporary Pain from the injection through the tympanic membrane
Rare chance of Ear Infection
Temporary Giddiness, from the caloric effect of the injection
Little to no risk of Eardrum Perforation