Idiopathic sudden sensorineural hearing loss (ISSHL) is a condition where there is something wrong with the sensory organs of the inner ear or the nerve pathways between the inner ear and the brain. While 10 percent of patients will have an underlying cause for this sudden deafness, most patients do not. Many people notice the loss of hearing when they wake in the morning or some may experience a “pop” in the ear before the loss occurs. They may experience the feeling of fullness in the ear, dizziness, or ringing in the ears. The hearing loss can be immediate, or the loss can come on gradually, with sounds becoming muffled or faint.

How is ISSHL Diagnosed?

If you experience sudden hearing loss, your physician will run a number of tests to rule out any potential underlying cause, starting with loss due to an obstruction in the ear, such as a buildup of fluid or wax. The next test is typically pure tone audiometry, which looks at how loud frequencies need to be before you can hear them. A loss of at least 30 decibels shows signs of SSHL. In this case, normal speech levels would sound like a faint whisper.

Treatment with HBOT

HBOT was found to provide a significant benefit as an additional treatment option, along with systemic and/or intratympanic corticosteroids. In particular, this study demonstrates for the first time to date that HBOT + MT is associated with a significant improvement in complete hearing recovery and in any hearing recovery compared with MT alone. This finding is important evidence for the clinical implications of HBOT in SSNHL treatment. To date, hypotheses about the benefit of HBOT have been suggested based on various theoretical backgrounds. The structures in the cochlea are vulnerable to a decrease in tissue oxygen supply 

In addition, the supply to the cochlea depends on oxygen diffusion through the capillaries rather than direct vascular oxygenation. Therefore, it is thought that the reduction of blood flow to the inner ear and resultant ischemia are the most important mechanisms for the occurrence of idiopathic SSNHL. Using HBOT, it is possible to maximize the oxygen partial pressure supplied to the inner ear. This process can minimize ischemic damage after SSNHL and aid vascular recovery. Furthermore, it can provide antibacterial effects through oxygen radicals and promote angiogenesis with tissue regeneration.

In order to qualify for OHIP covered hyperbaric oxygen therapy for idiopathic sensorineural hearing loss (ISSHL) or sudden hearing loss, one needs to present an audiology report showing at least a 30db loss or more in one or more ears within 30 days of starting HBOT. A referral from a physician or specialist is preferred, however it is not absolutely necessary. Our medical director will look over all supporting documentation, and make the ultimate decision for qualification.