Audiological and clinical outcomes of a transcutaneous bone conduction hearing implant: Six-month results from a multicentre study.

OBJECTIVES: To compare the hearing performance of patients with conductive and mild mixed hearing loss and single-sided sensorineural deafness provided with a new transcutaneous bone conduction hearing implant (the Baha Attract System) with unaided hearing as well as aided with a sound processor on a softband. Furthermore, to evaluate safety and subjective benefit before and after implantation of the test device. PARTICIPANTS: Fifty-four adult patients in five participating centres were enrolled in this prospective study. Baseline data were collected during a pre-operative visit, and after a softband trial, all patients were implanted unilaterally. Follow-up visits were scheduled at 10 days, 4, 6, 12 weeks and 6 months. MAIN OUTCOME MEASURES: Free-field hearing thresholds pure-tone average (PTA4 in dB HL; mean threshold at 500, 1000, 2000, 4000 Hz; primary outcome measure). Individual free-field hearing thresholds, speech recognition in quiet and in noise, soft tissue status during follow-up and subjective benefit as measured with the Abbreviated Profile of Hearing Aid Benefit (APHAB), Speech, Spatial and Qualities of Hearing Scale (SSQ) and Health Utilities Index (HUI) questionnaires. RESULTS: Implantation of the Baha Attract System resulted in favourable audiological outcomes compared to unaided conditions. On the primary outcome parameter, a statistically significant improvement was observed compared to unaided hearing for the patients with conductive/mixed hearing loss (mean PTA4 difference -20.8 dB HL, SD 9.8; P < 0.0001) and for the patients with single-sided sensorineural deafness (SSD) (mean PTA4 difference -21.6 dB HL, SD 12.2; P < 0.0001). During all audiology tests, the non-test ear was blocked. Statistically significant improvements were also recorded in speech tests in quiet and noise compared to unaided hearing for the conductive/mixed hearing loss group and for speech in quiet in the SSD group. Compared to the pre-operative measurement with softband, no significant differences were recorded in the PTA4 free-field hearing threshold or the other audiological outcomes in either of the groups (P > 0.05). Soft tissue-related issues observed during follow-up included numbness, pain/discomfort at the implant site and to a lesser extent pressure-related skin complications. A declining trend was noted in the rate of these complications during follow-up. Approximately 20% of patients reported some degree of numbness and 38% (slight) pain/discomfort at final follow-up of 6 months. Good results on the subjective benefit questionnaires were observed, with statistically significant improvements on APHAB and SSQ questionnaires, and on the hearing attribute of HUI3. CONCLUSIONS: The Baha Attract System provided a significant improvement in hearing performance and subjective benefit compared to the pre-operative unaided condition (with the non-test ear blocked). Hearing performance of the Baha Attract was similar to a test situation with the same sound processor on a softband. A proportion of the patients reported numbness and pain/discomfort at the implant site during follow-up, especially during the first post-operative weeks. Based on the results of the current multicentre study, the Baha Attract can be considered as a treatment option for patients with the aforementioned hearing losses. Especially in the SSD patients, a careful selection procedure is warranted. Therefore, a pre-operative trial should be part of the decision-making process before fitting a patient with the Baha Attract System.

Stability, Survival, and Tolerability of an Auditory Osseointegrated Implant for Bone Conduction Hearing: Long-Term Follow-Up of a Randomized Controlled Trial.

OBJECTIVE: To compare implant stability, survival, and soft tissue reactions for a novel (test) and previous generation (control) percutaneous auditory osseointegrated implant for bone conduction hearing at long-term follow-up of 5 years. STUDY DESIGN: Single follow-up visit of a previously completed multicenter, randomized, controlled trial. PATIENTS: Fifty-seven of the 77 participants of a completed randomized controlled trial on a new auditory osseointegrated implant underwent a single follow-up visit 5 years after implantation, which comprised implant stability measurements and collection of Holgers scores. Additionally, implant survival was recorded for all 77 patients from the original trial. RESULTS: The test implant showed significantly higher implant stability quotient (ISQ) values compared with the control implant throughout the 5-year follow-up. Mean area under the curve of ISQ high from baseline to 5 years was 71.6 (standard deviation [SD] ±2.0) and 66.7 (SD ±3.4) for the test and control implant, respectively (p < 0.0001). For both implants, the mean ISQ value recorded at 5 years was higher compared with implantation (test group +2.03 [SD ±2.55, within group p < 0.0001] and control group +2.25 [SD ±4.95, within group p = 0.12]). No difference was noticed in increase from baseline between groups (p = 0.64). Furthermore, evaluation of soft tissue reactions continued to show superiority of the test implant. At the 5-year follow-up visit, one patient (2.5%) presented with a Holgers grade 2 in the test group, compared with four patients (23.5%) in the control group (p = 0.048); no patient presented with more severe soft tissue reactions. Excluding explantations, the survival rate was 95.8% for the test group and 95.0% for the control group. The corresponding rates including explantations were 93.9 and 90.0%. CONCLUSION: The test implant showed superiority in terms of higher mean ISQ values and less adverse soft tissue reactions, both at the single 5-year follow-up visit and during the complete follow-up. In addition, both implants showed an equally high implant survival.

Percutaneous bone-anchored hearing implant surgery: inside or outside the line of incision?

The objective of this historical cohort study was to compare soft tissue reactions in adults after bone-anchored hearing implant (BAHI) surgery when the percutaneous implant is placed inside or outside the line of incision. All adult patients who received a percutaneous BAHI between 1 January 2010 and 31 January 2014 in our tertiary referral centre were identified. Patients were selected if operated by two surgeons, who perform the same standardised linear incision technique with one of them placing the implant outside the incision while the other prefers placement inside the line of incision. A total of 202 patients and 211 implants were included in the case analysis. The results showed the registration of a soft tissue reaction Holgers ≥1 in 47 implants (49.0 %) placed outside the incision compared to 70 implants (60.9 %) which were placed inside the line of incision. An adverse soft tissue reaction, Holgers ≥2, was noticed in 17 implants (17.7 %), respectively, 20 implants (17.4 %). No significant differences were found between the two groups for both the presence of soft tissue reactions Holgers ≥1 (p = 0.322) and a Holgers score ≥2 (p = 0.951). During the follow-up three implants were lost (1.4 %) and in 18 of 211 implants one or multiple revisions were performed (8.5 %). In conclusion, this study did not show any differences in the presence of postsurgical (adverse) soft tissue reactions between placement of the percutaneous BAHI inside or outside the line of incision.

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

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.

Loading of osseointegrated implants for bone conduction hearing at 3 weeks: 3-year stability, survival, and tolerability.

The objective of this study was to ascertain the long-term safety of loading osseointegrated implants for bone conduction hearing 3 weeks post-surgery. Thirty consecutive adult patients were implanted with the Baha BI300 (Cochlear Bone Anchored Solutions) in our tertiary referral center. Implants were loaded with the sound processor 3 weeks post-surgery. Follow-up examinations were performed at 10 days; 3, 4, 6, 8, and 12 weeks; 6 months; and 1, 2, and 3 years after implant surgery. At each follow-up visit, implant stability quotient (ISQ) values were recorded by means of resonance frequency analysis, and soft tissue status was evaluated according to Holgers' classification. ISQ trends, implant survival, and soft tissue reactions were compared to a population of 52 patients with the same type of implants loaded from 6 weeks post-surgery as part of another study. Subjective benefit was measured by means of the Glasgow Benefit Inventory (GBI). After an initial dip in ISQ at 10 days after implantation, a gradually increasing trend in ISQ was found until 6 months in both populations, after which ISQ values remained above baseline values. Implant survival was 97 % in the study population and 96 % in the comparison population. Clinically relevant soft tissue reactions were found in 0.9 % (study population) and 1.7 % (comparison population) of all visits. Patients reported subjective benefit; the mean GBI score was 22.8. In conclusion, loading these implants at 3 weeks post-surgery is safe based on the current study, as long-term results show high ISQ values and good implant survival and tolerability.

Stability, survival, and tolerability of a 4.5-mm-wide bone-anchored hearing implant: 6-month data from a randomized controlled clinical trial.

The objective of this study was to compare the stability, survival, and tolerability of 2 percutaneous osseointegrated titanium implants for bone conduction hearing: a 4.5-mm diameter implant (test) and a 3.75-mm diameter implant (control). Fifty-seven adult patients were included in this randomized controlled clinical trial. Sixty implants were allocated in a 2:1 (test-control) ratio. Follow-up visits were scheduled at 7, 14, 21, and 28 days; 6 and 12 weeks; and 6 months. At every visit, implant stability quotient (ISQ) values were recorded by means of resonance frequency analysis (RFA) and skin reactions were evaluated according to the Holgers classification. Implants were loaded with the bone conduction device at 3 weeks. Hearing-related quality of life was evaluated using the Abbreviated Profile of Hearing Aid Benefit (APHAB), the Glasgow Benefit Inventory (GBI), and the Glasgow Health Status Inventory (GHSI). ISQ values were statistically significantly higher for the test implant compared to the control implant. No implants were lost and soft tissue reactions were comparable for both implants. Positive results were reported in the hearing-related quality of life questionnaires. These 6-month results indicate that both implants and their corresponding hearing devices are safe options for hearing rehabilitation in patients with the appropriate indications. Loading at 3 weeks did not affect the stability of either implant.

Clinical results of Cochlear™ BIA300 in children: Experience in two tertiary referral centers.

OBJECTIVES: To evaluate clinical outcomes of the Cochlear™ BIA300 in the pediatric population. STUDY DESIGN: Historical cohort study. SETTING: Two tertiary referral centers. PATIENTS: All patients implanted with the BIA300 from November 2011 to January 2014 and 17 years or younger during surgery were included in this cohort study. MAIN OUTCOME MEASURES: Number of soft tissue reaction scores according to Holgers, local and systemic treatment of soft tissue reactions, revision surgeries and implant loss. RESULTS: Since introduction of the BIA300, 79 children have been implanted in both centers. During the mean follow-up of 11.7 months per implant, 15.7% of 115 implants received at least two local treatments for peri-abutment soft tissue reactions. Moreover, in 32 implants an adverse soft tissue reaction (Holgers 2 or higher) was noted at least once. In 28.7% of implants one or multiple revision surgeries were required. Implant loss occurred in 4 patients (3.5% of all implants), additionally, in five children the abutment had to be removed because of persistent soft tissue problems. CONCLUSIONS: The current study confirms good implant survival for these implants in pediatric patients. The number of adverse soft tissue reactions found in the current study resembles numbers reported on previous generation implants and abutments in children. However, for revision surgery (soft tissue revision and/or abutment change), an increase in frequency is noticed compared to reported results on previous generation implants and abutments, whether this is the result of the new implant or other factors cannot be concluded on the current series. The total aspect of the presented data are of importance in the decision making for a specific type of percutaneous bone anchored hearing implant.

A Retrospective Cohort Study on the Influence of Comorbidity on Soft Tissue Reactions, Revision Surgery, and Implant Loss in Bone-anchored Hearing Implants.

OBJECTIVE: To identify risk factors for complications after bone-anchored hearing implant (BAHI) surgery. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary referral center. PATIENTS: All adult patients who received titanium bone-anchored hearing implants at our clinic between September 1, 1988 and December 31, 2007 were approached to fill out a questionnaire on comorbidity factors. A total of 581 patients with 669 implants were included in the analysis. MAIN OUTCOME MEASURES: Implant loss, soft tissue reactions, and revision surgery after BAHI implantation. RESULTS: Skin disease and profound learning difficulties were risk factors for time to first soft tissue reaction, hazard rate ratio of 3.41 (95% CI 1.45-8.01) and 3.42 (1.03-11.39), respectively. Female gender showed a trend toward a negative risk for time to first soft tissue reaction, hazard rate ratio 0.60 (0.35-1.03). In multivariable analysis, skin disease and female gender were observed as independent associative factors, adjusted hazard ratio 3.08 (1.32-7.16) and 0.56 (0.33-0.94). For revision surgery, female gender and cardiovascular disease were identified as negative risk factors in univariable analysis, and smoking showed a trend toward a negative risk, with hazard ratios of 0.15 (0.07-0.32), 0.07 (0.03-0.20), and 0.51 (0.24-1.07), respectively. In multivariable analysis, smoking and female gender were observed as independent associative factors, adjusted hazard ratio 0.45 (0.22-0.95) and 0.14 (0.06-0.30). Smoking could be identified as a risk factor for implant loss with a hazard ratio of 3.32 (1.36-8.09). CONCLUSION: Retrospective analysis of comorbidity factors and clinical outcomes revealed risk factors for postoperative complications after BAHI surgery.