Results of a 2-Year Prospective Multicenter Study Evaluating Long-term Audiological and Clinical Outcomes of a Transcutaneous Implant for Bone Conduction Hearing.

OBJECTIVE(S): To evaluate 2-year audiological and clinical outcomes of a transcutaneous implant for bone conduction hearing of a previously published 6-month evaluation. DESIGN: Fifty-four unilaterally implanted adult patients with conductive or mild mixed hearing loss or single-sided sensorineural deafness were included in this prospective multicenter study. Follow-up visits were scheduled post-surgery at 10 days; 4, 6, and 12 weeks; 6, 12, and 24 months. Main outcomes were audiological benefit, patient-reported outcomes (PROs), soft tissue status, pain, numbness, implant survival, and daily usage. RESULTS: In the study population, the transcutaneous implant resulted in statistically significant improvement in objective hearing test and PROs compared with the unaided situation. Soft tissue complications were observed in 4.6% of the patients per visit. Pain/discomfort and numbness were initially reported in the majority of the patients, but declined over time; approximately 9% of patients reported some degree of numbness and 15% (slight) pain/discomfort after 2 years. During the 24-month period, two implant magnets were removed (3.7%), while two other implants were converted to the percutaneous counterpart (3.7%). At the final visit, 89.6% (n = 42 out of 47) of the patients used their sound processor, with a median daily usage of 6 h/d (range, 0-18 h/d). CONCLUSIONS: After 24 months, the transcutaneous implant provided statistically significant mean improvement in objective and subjective hearing performance as well as PROs compared with the preoperative unaided condition and had a low soft tissue complication rate. The test device could be considered as an alternative treatment option for appropriately selected and counseled patients.

Six-Month Clinical Outcomes for Bone-Anchored Hearing Implants: Comparison Between Minimally Invasive Ponto Surgery and the Linear Incision Technique With Tissue Preservation.

OBJECTIVES: The aim of this study is to investigate and compare the clinical outcomes of minimally invasive ponto surgery (MIPS) to the linear incision technique with soft tissue preservation (LIT-TP) for percutaneous bone-anchored hearing implants (BAHI). STUDY DESIGN: Prospective cohort study with a historical control group. SETTING: Tertiary referral center. PATIENTS: Twenty-five patients were prospectively included in the test group. The control group consisted of 25 patients who previously participated in another clinical trial and already underwent BAHI surgery. INTERVENTION: All patients were implanted with a 4.5-mm-wide implant, using MIPS in the test group and the LIT-TP in the control group. Follow-up visits were scheduled 7 days, 21 days (sound processor fitting), 12 weeks and 6 months after surgery. MAIN OUTCOME MEASURES: The primary outcome measure was skin sensibility around the abutment 6 months after surgery. Secondary outcomes were subjective numbness, surgery time, wound healing, adverse soft tissue reactions, cosmetic outcomes, implant stability quotient (ISQ), implant survival, and sound processor use. RESULTS: Skin sensibility, adverse soft tissue reactions, and sound processor use were comparable between groups. The test group had a shorter surgery time and better cosmetic outcomes. More skin dehiscences and a statistically nonsignificant higher implant loss rate (12% vs 0%, p = 0.079) were observed in the test group. CONCLUSION: MIPS is comparable to the LIT-TP regarding skin sensibility at 6 months and soft tissue tolerability. With MIPS, surgery time is further reduced and better cosmetic outcomes are reported. More research into MIPS, exact drill protocol, used instruments, and associated implant loss is warranted.

Economic Evaluation of Percutaneous Titanium Implants for Bone Conduction Hearing: A Cost-benefit Analysis.

INTRODUCTION: Developments in bone-anchored hearing implants have resulted in fewer complications, and, thus, lower complication-related costs. However, a weighing of the potential clinical benefits with higher implant purchase price is lacking. METHODS: A mathematical Markov model was used to evaluate the total costs (complication costs, implant purchase price, and standard costs) of three widely used current generation implants with expected similar outcomes, compared to a previous generation implant in adult patients over a 10-year time horizon from a healthcare perspective. Parameter estimates were derived from published clinical literature. Missing parameter estimates were based on expert opinion. Implant costs were derived from manufacturer catalogues, while standard and complication costs related to the BAHI were derived from a Dutch University Hospital and Dutch guideline for cost-effectiveness research. RESULTS: The average total costs of the treatment with a previous generation implant was &OV0556;4.967 (SD ±â€Š&OV0556;134) per patient over a 10-year time horizon, compared to &OV0556;4.678 (SD ±â€Š&OV0556;83) with a current generation implant. This implant type is potentially up to &OV0556;506 more beneficial per patient over a 10-year horizon. By further improving implant survival, an additional &OV0556;645 (SD ±â€Š&OV0556;86) per patient could be saved over 10 years. CONCLUSION: Despite a higher initial purchase price, the current generation implants are potentially cost-beneficial compared with previous generation implants. More data on current generation implants is needed to be able to determine which of the newer implants is most cost-beneficial. Focussing future developments on improving implant survival is likely to have more impact on costs compared with developments on improving soft tissue tolerability.

Three-Year Clinical and Audiological Outcomes of Percutaneous Implants for Bone Conduction Devices: Comparison Between Tissue Preservation Technique and Tissue Reduction Technique.

OBJECTIVES: To evaluate the three-year clinical and audiological outcomes of soft-tissue preservation compared to soft-tissue reduction in linear incision surgery for percutaneous implant for bone conduction (BC) devices. METHODS: Twenty-five patients (25 implants) were enrolled in a prospective cohort for implant surgery with linear incision and tissue preservation. The control group consisted of 25 patients (25 implants) from a previous randomized controlled trial in which a linear incision with soft-tissue reduction was applied. Follow-up visits were scheduled at 7 and 21 days (fitting of sound processor); 12 weeks; 6 months; and at 1, 2, and 3 years after implantation. Main outcome measures were skin sensibility, soft-tissue status, Implant Stability Quotient (ISQ), skin height, implant survival, revision surgery, scar assessment, and hearing thresholds (BC in-situ between 250 Hz and 8 kHz with BC device on testband and abutment, and BC thresholds at 250Hz-4 kHz with a B71 bone conductor). RESULTS: Tissue preservation resulted in superior sensibility (mean percentage correct responses 99.7% [SD 1.7] vs 92.0% [SD 9.2], p = 0.0001). No spontaneous implant loss occurred in either group. The abutment was removed in two tests and in one control patient. Two control patients needed skin revision surgery. Although not statistically significant, more adverse soft-tissue reactions (Holgers ≥2) were observed in the test-group (n = 9 [36%] vs n = 3 [12%], p = 0.095). ISQ increased significantly more in the test group compared to the control group (7.64 [SD 4.05] vs 4.29 [SD 3.93]). Skin thickening, scar assessment, and hearing outcomes were comparable. CONCLUSION: Tissue preservation demonstrated superior skin sensibility compared to tissue reduction while other clinical outcomes were comparably excellent.

Three-year Outcomes of a Randomized Controlled Trial Comparing a 4.5-mm-Wide to a 3.75-mm-Wide Titanium Implant for Bone Conduction Hearing.

OBJECTIVE: To compare 3-year implant stability, survival, and tolerability of a 4.5-mm-wide (test) and a 3.75-mm-wide (control) percutaneous titanium implant for bone-conduction hearing, loaded with the sound processor after 3 weeks. METHODS: Sixty implants were allocated in a 2:1 ratio (test-control) in 57 adult patients included in this prospective randomized controlled clinical trial. Follow-up visits were performed at 7, 14, 21, and 28 days; 6 and 12 weeks; 6 months; and at 1, 2, and 3 years after implantation. During these visits, the implant stability quotient (ISQ) was measured by means of resonance frequency analysis (RFA). The peri-abutment soft tissue status was assessed according to the Holgers classification. Skin height around the abutment was evaluated. RESULTS: The mean area-under-the-curve (AUC) of ISQ-low was statistically significantly higher for the test implant (65.7 versus 61.4, p = 0.0002). Both implants showed high survival rates (97.4% versus 95.0%, p = 0.6374). Adverse soft tissue reactions were observed sporadically, with no significant inter-group differences. Skin thickening was seen in the majority of the patients, but no correlation with adverse soft tissue reactions or implant type was observed. CONCLUSION: The 4.5-mm-wide implant provides significantly higher ISQ values during the first 3 years after surgery compared with the previous generation 3.75-mm-wide implant. Both implants showed high survival rates and good tolerability. These long-term results indicate that the wider implant, loaded with a sound processor at 3 weeks, is a safe and well-performing option for hearing rehabilitation in specific types of hearing loss.

Gamma Knife radiosurgery for treatment of growing vestibular schwannomas in patients with neurofibromatosis Type 2: a matched cohort study with sporadic vestibular schwannomas.

OBJECTIVE Neurofibromatosis Type 2 (NF2) is a tumor syndrome characterized by an autosomal dominant pattern of inheritance. The hallmark of NF2 is the development of bilateral vestibular schwannomas (VSs), generally by 30 years of age. One of the first-line treatment options for small to medium-large VSs is radiosurgery. Although radiosurgery shows excellent results in sporadic VS, its use in NF2-related VS is still a topic of dispute. The aim of this study was to evaluate long-term tumor control, hearing preservation rates, and factors influencing outcome of optimally dosed, contemporary Gamma Knife radiosurgery (GKRS) for growing VSs in patients with NF2 and compare the findings to data obtained in patients with sporadic VS also treated by means of GKRS. METHODS The authors performed a retrospective analysis of 47 growing VSs in 34 NF2 patients who underwent GKRS treatment performed with either the Model C or Perfexion Leksell Gamma Knife, with a median margin dose of 11 Gy. Actuarial tumor control rates were estimated using the Kaplan-Meier method. For patient- and treatment-related factors, a Cox proportional hazards model was used to identify predictors of outcome. Trigeminal, facial, and vestibulocochlear nerve function were assessed before and after treatment. NF2-related VS patients were matched 1:1 with sporadic VS patients who were treated in the same institute, and the same indications for treatment, definitions, and dosimetry were used in order to compare outcomes. RESULTS Actuarial tumor control rates in NF2 patients after 1, 3, 5, and 8 years were 98%, 89%, 87%, and 87%, respectively. Phenotype and tumor volume had significant hazard rates of 0.086 and 22.99, respectively, showing that Feiling-Gardner phenotype and a tumor volume not exceeding 6 cm3 both were associated with significantly better outcome. Actuarial rates of serviceable hearing preservation after 1, 3, 5, and 7 years were 95%, 82%, 59%, and 33%, respectively. None of the patients experienced worsening of trigeminal nerve function. Facial nerve function worsened in 1 patient (2.5%). No significant differences in tumor control, hearing preservation, or complications were found in comparing the results of GKRS for NF2-related VS versus GKRS for sporadic VS. CONCLUSIONS With modern GKRS, the use of low margin doses for treating growing VSs in patients with NF2 demonstrates good long-term tumor control rates. Feiling-Gardner phenotype and tumor volume smaller than 6 cm3 seem to be independently associated with prolonged progression-free survival, highlighting the clinical importance of phenotype assessment before GKRS treatment. In addition, no significant differences in tumor control rates or complications were found in the matched-control cohort analysis comparing GKRS for VS in patients with NF2 and GKRS for sporadic VS. These results show that GKRS is a valid treatment option for NF2-related VS, in addition to being a good option for sporadic VS, particularly in patients with the Feiling-Gardner phenotype and/or tumors that are small to medium in size. Larger tumors in patients with the Wishart phenotype appear to respond poorly to radiosurgery, and other treatment modalities should therefore be considered in such cases.