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communication challenges that arise and not having
previous experience or need to comprehend manual
communication. Depending on the etiology, these
patients may still be candidates for CI after bilateral
hearing loss, but pre-emptive implantation at an early age
can limit the duration of deafness in the worse hearing ear
and hence improve likely outcomes if the threatened ear
is not viable for implantation.
Additionally, a cochlear implant can provide assurance
that if and when the patient loses hearing in the threat-
ened only hearing ear that they will not be completely
‘‘off line’’ with their cochlear implant. We have found
this to be important in patients even in cases where the
electric signal is not well integrated during the interval of
persistent acoustic hearing as these patients quickly adapt
to electric only hearing once further loss occurs.
Absolute Indication: Pediatric Progressive Hearing
Loss
Although criteria continue to be defined, cochlear
implant candidacy for SSD is most favored in younger
patients with progressive conditions such as enlarged
vestibular aqueduct (EVA), genetic conditions, auto-
immune inner ear disease, ototoxicity, and certain meta-
bolic diseases. Since the good ear is likely to decline
eventually, re-establishing hearing in the poorer ear
avoids the untoward sequelae of long duration of deaf-
ness and total auditory deprivation.
Counseling and Other Considerations
Just as in any family with children undergoing evalu-
ation for a cochlear implant, an important part of the
preoperative counseling includes ensuring patients and
their families understand the range of possible outcomes
as well as the considerable time and effort required for
optimal performance with the device. Additionally,
particular consideration should include discussion about
subjective performance and progress over time, in
addition to objective testing. An assessment of functional
impairments may be more important than objective
audiologic testing, most of which may be relatively
normal with one hearing ear. For those children who
are school age, one should inquire of the family whether
they have noted difficulty in particular listening con-
ditions, in social interactions, or in reports from teachers.
Another consideration is the very young child with
SSD. With acknowledgement that some children with
SSD grow up to be well-functioning adults and adapt
well, these outcomes are difficult to predict. The devel-
oping brain is at maximal neuroplasticity at a young age
and so a prolonged period of auditory deprivation may
compromise ultimate auditory performance with treat-
ment. By analogy to adults, there are some adults who
have lived with SSD without perceived difficulty,
whereas others have found it challenging and no factors
have yet been identified to know which patients fall into
which group. Unfortunately, attempting to clarify these
unknowns introduces a paradox. Waiting until a child
gets older may allow a better determination of the impact
of the hearing loss on functioning and learning, but this
wait introduces a longer duration of deafness, a negative
relationship in predicting CI outcomes. A recent review
of the experience in Freiburg, Germany, with pediatric
SSD indicates that children with acquired hearing loss
and a shorter duration of hearing loss outperformed those
with a longer duration of SSD (14). It is important that the
family understands all of these considerations when
making the decision with the cochlear implant team.
Additionally, at this early stage of investigation, suc-
cessfully obtaining financial reimbursement surrounding
the surgery, the device and associated visits to the
implant center represent an important obstacle to its
wider adoption.
Relative Contraindications
After a certain period of time, as yet undefined, one
might expect the length of deafness to be too long for the
benefits of cochlear implants to be realized. Until data
clarify such a cut-off, implantation with proper counsel-
ing may be considered.
CONCLUSIONS
SSD can have a significant impact on developmental
spheres and various aspects of quality of life. An
informed discussion to include all available therapies
and their respective advantages and disadvantages with
the family and CI team is essential to the decision-
making process. Early experience with SSD CI recipients
suggests that cochlear implantation, with appropriate
preoperative assessment and counseling and postopera-
tive management, may offer these patients the best
opportunity to realize the benefits of binaural hearing.
Although in our center, certain conditions seem like clear
indications, further data will be necessary before this
treatment modality is advocated more widely.
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