Date of Degree


Document Type

Capstone Project

Degree Name





Carol A. Silverman

Subject Categories

Speech Pathology and Audiology


auditory brainstem implant, adult, postlingual, neurofibromatosis type 2, nontumor, speech recognition


Objective:The purpose of this investigation is to conduct a systematic review of the long-term speech-recognition outcomes of ABIs in postlingually deafened adults, and to compare outcomes of ABIs in adults with NF2/tumors to adults without NF2.

Methods: A comprehensive search utilizing various peer reviewed databases via the City University of New York (CUNY) Graduate Center Library was conducted to identify relevant studies investigating speech-recognition outcomes in ABI patients with postlingual deafness, both with and without tumors. Inclusion criteria included studies that involved at least one adult ABI patient (with or without NF2) with postlingual deafness, who was seen for follow-up auditory performance testing at one-year post-activation or later.

Results: Thirteen articles met inclusion criteria for this systematic review. The studies utilized various materials for speech-recognition assessment to evaluate speech-recognition performance. Because of the great diversity among the materials used for speech-recognition assessment, the measures have been categorized as either closed-set (CS) or open-set (OS). Total overall sample size across the 13 included studies was 170. Of the 170 participants, 91 (54%) were adults with postlingual deafness; 76 participants (84%) were adults with NF2, and 15 participants (16%) were adults without NF2.

Discussion: Significant long-term improvement and overall good closed-set and fair open-set speech performance with use of the ABI only was found for the participants with NF2. Participants with NF2 also performed better on closed-set and open-set tests when using the ABI in conjunction with LR. Improved open-set performance was also observed in the ABI+LR condition for individuals without NF2.

Conclusions: Results of ABI are unpredictable and a wide range in speech-recognition performance was observed. ABIs generally provide good support in the communication skills of deafened patients, especially in combination with lip reading. Standardization of speech-recognition performance testing and clinical case reporting will be crucial to make more definitive statements about the factors that influence these outcomes, as the indications for ABI implantation in both postlingually and prelingually deafened individuals continues to expand.