Controlled Clinical Trial on Bone-anchored Hearing Implants and a Surgical Technique With Soft-tissue Preservation

Abstract

OBJECTIVE: To compare the clinical and audiological outcomes after linear incision with soft-tissue preservation and standard linear incision with soft-tissue reduction for placement of percutaneous bone-anchored hearing implants. STUDY DESIGN: Clinical trial with historical control-group from a previous randomized controlled trial. SETTING: Tertiary referral center. PATIENTS AND INTERVENTIONS: Twenty-five patients were enrolled in a prospective cohort of bone-anchored hearing implant placement with linear incision and tissue preservation with a follow-up of 6 months. The control-group consisted of 25 patients from a previous randomized controlled trial in the same tertiary referral center. All sound processors were fitted 3 weeks after surgery. MAIN OUTCOME MEASURES: Numbness around the abutment, length of surgery, soft-tissue reactions according to Holgers' classification, Patient and Observer Scar Assessment Scale, implant loss, Implant Stability Quotient, and audiological outcome. RESULTS: Tissue preservation resulted in better results on sensibility (mean percentage correct responses 98% [SD 4.4] versus 89% [SD 15.0], p = 0.003), on the Patient and Observer Scar Assessment Scale (mean observer score 15.3 [SD 4.3] versus 19.4 [SD 6.3], p = 0.006), and shorter total surgery time (mean 24.6 min [SD 6.2] versus 31.9 min [SD 6.5], p < 0.001). More adverse soft-tissue reactions as measured by the Holgers classification were observed in the test-group (n = 7 [28%] versus n = 1 [4%], p = 0.049). For Implant Stability Quotient and audiology the study did not provide evidence that tissue preservation is better or worse compared with tissue reduction. CONCLUSION: Tissue preservation compared with tissue reduction leads to a generally favorable clinical outcome, comparable audiology results, and significantly shorter surgery time. Longer follow-up is warranted to conclude on the increased adverse soft-tissue reactions after 6 months.