Yvette E. Smulders

The Cost-utility of bilateral cochlear implantation: A Systematic Review

The (cost‐)effectiveness and the subsequent reimbursement of bilateral cochlear implantation has been vigorously debated. Throughout the world healthcare commissioners are still struggling with the decision to reimburse bilateral implantation. Given this debate, this studys objective was to review the literature on the cost‐utility of bilateral cochlear implantation in both children and adults, and study the impact of the used cost and quality‐of‐life estimates.

What is the effect of time between sequential cochlear implantations on hearing in adults and children? A systematic review of the literature

Bilateral cochlear implantation is a safe and effective intervention for severe sensorineural hearing loss and is believed to be more effective than unilateral implantation. This review article investigates the effect of time between sequential cochlear implantations on hearing results in both adults and children.

Effect of unilateral and simultaneous bilateral cochlear implantation on tinnitus: A Prospective Study.

To determine the effect of cochlear implantation on tinnitus perception in patients with severe bilateral postlingual sensorineural hearing loss and to demonstrate possible differences between unilateral and bilateral cochlear implantation.

Stable benefits of bilateral over unilateral cochlear implantation after two years: A randomized controlled trial

To investigate hearing capabilities and self‐reported benefits of simultaneous bilateral cochlear implantation (BiCI) compared with unilateral cochlear implantation (UCI) after a 2‐year follow‐up and to evaluate the learning effect of cochlear implantees over time.

Validation of the U-STARR with the AB-York crescent of sound, a new instrument to evaluate speech intelligibility in noise and spatial hearing skills

The Advanced Bionics® (AB)-York crescent of sound is a new test setup that comprises speech intelligibility in noise and localization tests that represent everyday listening situations. One of its tests is the Sentence Test with Adaptive Randomized Roving levels (STARR) with sentences and noise both presented from straight ahead. For the Dutch population, we adopted the AB-York setup and replaced the English sentences with a validated set of Dutch sentences. The Dutch version of the STARR is called the Utrecht-STARR (U-STARR). This study primarily assesses the validity and reliability of the U-STARR compared to the Plomp test, which is the current Dutch gold standard for speech-in-noise testing. The outcome of both tests is a speech reception threshold in noise (SRTn). Secondary outcomes are the SRTn measured with sounds from spatially separated sources (SISSS) as well as sound localization capability. We tested 29 normal-hearing adults and 18 postlingually deafened adult patients with unilateral cochlear implants (CI). This study shows that the U-STARR is adequate and reliable and seems better suited for severely hearing-impaired persons than the conventional Plomp test. Further, CI patients have poor spatial listening skills, as demonstrated with the AB-York test.

Cost-Utility of Bilateral Versus Unilateral Cochlear Implantation in Adults: A Randomized Controlled Trial

Objective: To study the cost–utility of simultaneous bilateral cochlear implantation (CI) versus unilateral CI. Study Design: Randomized controlled trial (RCT). Setting: Five tertiary referral centers. Patients: Thirty-eight postlingually deafened adults eligible for cochlear implantation. Interventions: A cost–utility analysis was performed from a health insurance perspective. Main Outcome Measures: Utility was assessed using the HUI3, TTO, VAS on hearing, VAS on general health and EQ-5D. We modeled the incremental cost per quality-adjusted life year (QALY) of unilateral versus bilateral CI over periods of 2, 5, 10, 25 years, and actual life-expectancy. Results: Direct costs for unilateral and bilateral CI were &OV0556;43,883 ± &OV0556;11,513(SD) and &OV0556;87,765 ± &OV0556;23,027(SD) respectively. Annual costs from the second year onward were &OV0556;3,435 ± &OV0556;1,085(SD) and &OV0556;6,871 ± &OV0556;2,169(SD), respectively. A cost–utility analysis revealed that a second implant became cost-effective after a 5- to 10-year period, based on the HUI3, TTO, and VAS on hearing. Conclusion: This is the first study that describes a cost–utility analysis to compare unilateral with simultaneous bilateral CI in postlingually deafened adults, using a multicenter RCT. Compared with accepted societal willingness-to-pay thresholds, simultaneous bilateral CI is a cost-effective treatment for patients with a life expectancy of 5–10 years or longer.

Development of a Squelch Effect in Adult Patients After Simultaneous Bilateral Cochlear Implantation

Objectives: To investigate whether a squelch effect occurs in the first 3 years after simultaneous bilateral cochlear implantation and to investigate whether this effect increases during follow-up. Study Design: Prospective study as part of a multicenter randomized controlled trial that compares simultaneous bilateral cochlear implantation to sequential and unilateral cochlear implantation. Setting: Tertiary referral center. Patients: Nineteen postlingually deafened adults. Intervention: Simultaneous bilateral cochlear implantation. Main Outcome Measure: The squelch effect, measured yearly with a speech-intelligibility-in-noise test with spatially separated sources. Bilateral results were compared to unilateral results in which the cochlear implant at the noise side was turned off. The squelch effect was investigated for the patients’ best performing ear and for the left and right ears separately. Results: In 13 individual patients, a squelch effect was present after 1 year. This number increased during follow-up years. On group level, a squelch effect was present in patients’ best performing ear after 2 and 3 years (1.9 dB). A squelch effect was present in both ears after 3 years (AS: 1.7 dB, AD: 1.3 dB). Conclusion: Patients who underwent simultaneous bilateral cochlear implantation developed a measurable benefit from the squelch effect after 2 years in their best performing ear and after 3 years in both ears. These observations suggest that the brain learns to use interaural differences to segregate sound from noise after simultaneous bilateral cochlear implantation. The squelch effect increased over time which suggests a growth in cortical integration and differentiation of inputs from bilateral CIs due to brain plasticity. Trial Registration: Dutch Trial Register NTR1722. Level of evidence: 1b.

Effect of unilateral and simultaneous bilateral cochlear implantation on tinnitus: A randomized controlled trial

To determine the effect of cochlear implantation on tinnitus perception in patients with severe bilateral postlingual sensorineural hearing loss and to demonstrate possible differences between unilateral and bilateral cochlear implantation.

Agreement between health utility instruments in cochlear implantation

The objectives of our study were threefold: to compare health utility scores measured with different health utility instruments in adult patients with bilateral deafness, to compare the change in health utility scores after unilateral or bilateral cochlear implantation using the different health utility instruments and to assess which health utility instrument would be the most appropriate for future studies on cochlear implantation.

Predicting Sequential Cochlear Implantation Performance: A Systematic Review

This systematic review of the literature reveals which preoperative factors affect sequential cochlear implantation outcomes in adults. The findings can help health care professionals provide evidence-based advice on the expected benefits from a second cochlear implant (CI). We searched PubMed, EMBASE, and the Cochrane database from November 1977 to August 26, 2017, using the terms “sequential cochlear implantation”; the most frequently cited predictors for unilateral cochlear implantation performance and other potential predictors for sequential implantation outcome; and “speech perception,” “localization” as well as synonyms of all of the above. Ten studies were included. The effects of age, duration of hearing loss, time between implantations, preoperative hearing, etiology of hearing loss, hearing aid use and duration of follow-up on sequential cochlear implantation performance were studied. The literature has shown that duration of deafness, age at onset of deafness, etiology of hearing loss, and preoperative speech perception score are (inversely) related to unilateral cochlear implantation outcome in adults. One would expect that these factors would also affect sequential bilateral implantation outcome. However, the best available evidence to date shows that advanced age, a long duration of deafness, or a long interval between implantations should not be considered negative factors when considering sequential bilateral cochlear implantation.