Introduction
Significant variability exists in angular insertion depth both across and within cochlear implant arrays, which could not be influenced in previous standard fittings. Anatomy-based fitting is a new fitting method that allows personalization. The prerequisite is new fitting software, in which patient-specific data can be imported from a planning platform for otological surgery. It is then possible to calculate and display each individual electrode contact’s tonotopic frequency. The audiologist can then set a frequency-band distribution that is more closely aligned to the tonotopic frequency distribution. The aim of this study was to 1) compare the benefit of a new fitting method with the established fitting methodology and 2) evaluate other influencing factors, e.g. insertion depth and electrode array length.
Methods
Participants are adults who are experienced unilateral or bilateral adult cochlear implant users. Speech perception in noise, pitch and timbre perception, and subjective preferences were assessed at a 3-month interval using the standardised clinical setting as well as the anatomy-based fitting.
Results
Experienced bilateral CI users benefit from the new fitting methodology when implanted with different electrode arrays. Speech perception is improved bilaterally in speech in noise testing, but may affect speech understanding on the weaker side. All unilateral patients implanted with a standard electrode array preferred the anatomy-based fitting. This is also reflected in improved speech perception in noise and better sound quality.
The initial acceptance of anatomy based fitting in experienced CI users is dependent on electrode array lenght and insertional angle. Anatomy based fitting should be considered as an alternative in dissatisfied CI users.
