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Vol. 66, No. 1 2015
Northeast Florida Medicine
Otolaryngology
but also include chemotherapeutic agents such as cisplat-
inum and loop diuretics. Unfortunately, the incidence of
ototoxic sensorineural hearing loss is much higher in the
developing world where aminoglycosides represent an in-
expensive treatment option for infections and blood levels
are frequently not monitored. Ménière’s disease represents
an idiopathic cause of hearing loss characterized by fluctu-
ation of hearing and spells of vertigo, which demonstrates
hydropic changes of the endolymph on histopathologic
examination of the temporal bone.
A sudden sensorineural hearing loss may occur for
unknown reasons. This represents a 30 decibel decline
in sensorineural hearing in three consecutive frequencies
over a three day period of time.
15
While multiple etiologies
have been suggested, including a viral origin or vascular
origin, the ultimate cause is unknown in 85 to 90 percent
of patients.
15
The hearing loss may manifest as a sensation
of blockage in the ear and may or may not have associated
tinnitus and balance related issues. Again, recent guidelines
from the American Academy of Otolaryngology-Head and
Neck Surgery have important implications for the recovery
of these patients.
15
Multiple studies have demonstrated that
patients who have more rapid access to treatment have a
higher rate of hearing recovery.
16
Poor prognostic factors
for hearing recovery include:
•
a profound hearing loss
•
associated balance symptoms
•
a higher frequency loss.
Academy guidelines also suggest differentiating a sen-
sorineural hearing loss from a conductive hearing loss by
expeditiously performing an audiogram.We consider this an
audiologic emergency at our facility.These patients should be
assessed for other neurologic changes, which might imply a
vascular etiology or an evolving cerebrovascular accident. A
CT scan is of little value in these patients, and most patients
with a sudden significant sensorineural hearing loss should
undergo a gadolinium enhancedMRI with special attention
to the internal auditory canals. Routine laboratory studies
are also of little value, and patients should be educated about
the natural course of this disease at the time of the diagnosis.
Once the diagnosis of a sudden sensorineural hearing loss
has been established, oral corticosteroids may be offered
to the patient, typically beginning at 60 mg of prednisone
daily for 10 days followed by rapid taper.
16
Intratympanic
steroid injections have been found to be beneficial in several
studies and may be offered either as a rescue procedure for
patients who fail to respond to oral steroids or the injections
may be given concomitanly with the oral corticosteroids.
17
Antiviral therapy, thrombolytics, vasoactive medications or
antioxidants are of little benefit with sudden sensorineural
hearing loss and should be avoided. Follow-up audiometric
testing within six months of the onset is appropriate and
should be offered to patients. Hyperbaric oxygen is also a
reasonable treatment option, although it is more commonly
used outside the US.
Treatment
Amplification
Great changes have occurred to hearing aids over the
past several decades. Miniaturization of hearing aids has
allowed the older body worn hearing aid to be replaced by
an ear level aid, and subsequently by very small hearing aids
completely hidden within the ear canal. As amplification has
improved, small Receiver in Canal (RIC) hearing aids are
being used with greater frequency because of the lack of an
occlusion sensation with the open fit molds used in these
aids. Patients with mid and high frequency sensorineural
hearing loss find these hearing devices to be helpful. The
ability to connect to a variety of sound sources via wireless
connectivity through a streamer has greatly enhanced the
functionality of hearing aids. Bluetooth technology allows
sound froma cellular phone, television, remotemicrophone,
or even a computer to be directly inputted to the patient.
Some newer hearing aids are even able to connect to various
sound sources without a streamer being worn around the
neck by using a smartphone to connect to the sound source.
1
Improvements in microphone technology and in the
amplification circuitry have also greatly improved the perfor-
mance of hearing aids. Directional microphone technology
using paired microphones allows the funneling of sound
from in front of the patient into the hearing aid limiting the
sound field and thereby reducing some background noise.
Improvements in feedback control, coupled with automatic
gain control, allow repackaging of the speech signal to fit
within the dynamic range of the patient’s hearing. The use of
digital technology has become routine among most hearing
aids that are sold today with digital noise reduction, and
digital signal processing has also become extremely common.
Hearing aids in Florida may either be purchased from a
licensed audiologist or from a hearing aid dispenser. Patients
need to be aware of the 30-day trial period that accompanies
the purchase of a hearing aid during which time they can
return the hearing aid for any reason if they are not satisfied.
The audiologist or hearing aid dispenser may retain a fitting
fee if the hearing aid is returned during this time frame.
Implantable hearing devices have also entered the discus-
sion for patients with significant hearing loss. Many patients
inquire about the Esteem Envoy device, an implantable
device, which utilizes a piezoelectric crystal for both the
reception of sound and also direct couplingwith the ossicular
