## 4 Discussion
[10], in a longitudinal study of 118 VSB devices with an average follow-up of 6.7 years (range 0.7 months-17.9 years), reported a 77% survival rate at the end of the observation period, lower than our reported value. Their device failure rate was 3.4%, and our device failure rate was 1% (two devices). The largest group of SAEs in our VSB dataset resulted in additional surgery or device explantation related to infection or an inflammatory response. These were adhesions (seven cases), ossicular damage (four cases), cholesteatoma (one case), device extrusion (one case), and wound infection (two cases). There were four other cases of wound infection, but these resolved readily with treatment with antibiotics. Eight of the SAE cases relating to infection or inflammatory response had a history of chronic ear infections. Adhesions are an inflammatory response and result in tissue growth in non-typical locations. This could be related to the etiological characteristics of the group, which has a high rate of individuals with a history of CSOM. It is generally accepted that estachian tube dysfunction can lead to middle ear pathologies such as retraction pockets, recurrent otitis media, serous otitis media, or cholesteatoma [11]. These can lead to histopathological inflammatory changes that may result in adhesions. This could support the idea of a greater likelihood of inflammatory responses in individuals with CSOM. This is speculative due to the low number of these cases in our series, which is too low for meaningful statistical analysis but of value for exploration in future observational studies. A history of CSOM indicates the importance of careful monitoring of ear health and device function postoperatively. [PERSON] et al. [12] included the VSB in a systematic review of AEs associated with BCHDs and aMEIs. They reported the main issues for the VSB to be explantation, device failure, repositioning of the floating mass transducer (FMT), fullness in the ear, dizziness, and pain. We did not find cases reporting fullness or dizziness. Our AEs included two cases requiring FMT repositioning, one case of mild tinnitus, and four cases of minor pain, two resolved by reducing magnet strength, one resolved with antibiotics, and one unresolved. For the VSB, many of the events were minor or resolved spontaneously, such as a facial nerve insult. Due to the surgical approach for the VSB being more complex than for the BB, there were more events occurring intraoperatively. There were five cases of facial nerve insult that resolved spontaneously, four cases of dural tear, and one case of ear canal damage that was repaired intraoperatively. There were four cases of irreversible chorda sacrifice and four cases of ossicular damage that resulted in explantation or led to hearing levels reducing beyond the criteria for the device. For most of these surgical events, there were no apparent associated etiological factors that could have predicted them. However, of the five cases of facial nerve injury, three were for individuals with congenital deafness. Conditions suggesting congenital abnormalitiesmay show an abnormal course of the facial nerve. In this situation, a patient considering VSB should be advised of the possible additional risk of temporary facial nerve insult during the initial consultation. Future analyses will explore audiometric outcomes, speech perception, device satisfaction, and quality of life. These analyses will provide the evidence required to support realistic expectations of device outcomes in line with the recommendations of the consensus statement [4].