Learning Objectives:

Objective: To evaluate the efficacy of the Slim Modiolar (CI532) array in delivering consistent scala tympani and perimodiolar placement of the electrode contacts in cochlear implant recipients.

Methods: The Nucleus CI532 device incorporates a new pre-curved, perimodiolar electrode array (EA32) with 22 contacts and a cross-sectional area of approximately 40% of that of the Contour Advance “CA” array with the same electrode length. The EA32 does not have a lumen and stylet like the current CA; instead it has a thin electrode which is introduced into the cochlea through a 0.7 mm diameter straightening sheath.

As part of a multicentre international clinical trial, 10 patients have received the CI532 implant at the Melbourne Cochlear Implant Clinic. Outcome measures have included intra-operative fluoroscopy and Neural Response Telemetry, Post operative Cone Beam CT and speech perception testing.

Results: Electrode placement was successful in all 10 recipients with confirmed Scala Tympani position and low wrapping factor indicating good perimodiolar proximity. Hearing performance at 6 months appears promising.

Conclusion: Initial clinical experience with the CI532 electrode has demonstrated successful placement in 10 patients without complication and excellent perimodiolar position.