Objective Endoscopic sinus surgery represents the gold standard for surgical treatment of chronic sinus diseases. Thereby, navigation systems can be of distinct use. In our study, we tested the recently developed KARL STORZ NAV1 SinusTracker navigation software that incorporates elements of augmented reality (AR) to provide a better preoperative planning and guidance during the surgical procedure. Methods One hundred patients with chronic sinus disease were operated on using either a conventional navigation software (n = 52, non‐AR, control group) or a navigation software incorporating AR elements (n = 48, AR, intervention group). Incidence of postoperative complications, duration of surgery, surgeon‐reported benefit from the navigation system and patient‐reported postoperative rehabilitation were assessed. Results The surgeons reported a higher benefit during surgery, used the navigation system for more surgical steps and spent longer time with preoperative image analysis when using the AR system as compared with the non‐AR system. No significant differences were seen in terms of postoperative complications, target registration error, operation time and postoperative rehabilitation. Conclusion The AR enhanced navigation software shows a high acceptance by sinus surgeons in different stages of surgical training and offers potential benefits during surgery without affecting the duration of the operation or the incidence of postoperative complications. Level of evidence 1b.

Hearing impairment is one of the most common sensory deficits in humans. Hearing aids are helpful to patients but can have poor sound quality or transmission due to insufficient output or acoustic feedback, such as for high frequencies. Implantable devices partially overcome these issues but require surgery with limited locations for device attachment. Here, we investigate a new optoacoustic approach to vibrate the hearing organ with laser stimulation to improve frequency bandwidth, not requiring attachment to specific vibratory structures, and potentially reduce acoustic feedback. We developed a laser pulse modulation strategy and simulated its response at the umbo (1–10 kHz) based on a convolution-based model. We achieved frequency-specific activation in which non-contact laser stimulation of the umbo, as well as within the middle ear at the round window and otic capsule, induced precise shifts in the maximal vibratory response of the umbo and neural activation within the inferior colliculus of guinea pigs, corresponding to the targeted, modelled and then stimulated frequency. There was also no acoustic feedback detected from laser stimulation with our experimental setup. These findings open up the potential for using a convolution-based optoacoustic approach as a new type of laser hearing aid or middle ear implant.

Hearing impairment affects ∼460 million people worldwide. Conservative therapies, such as hearing aids, bone conduction systems, and middle ear implants, do not always sufficiently compensate for this deficit. The optical stimulation is currently under investigation as an alternative stimulation strategy for the activation of the hearing system. To assess the biocompatibility margins of this emerging technology, we established a method applicable in whole-mount preparations of murine tympanic membranes (TM). We irradiated the TM of anesthetized mice with 532-nm laser pulses at an average power of 50, 89, 99, and 125 mW at two different locations of the TM and monitored the hearing function with auditory brainstem responses. Laserpower-dependent negative side effects to the TM were observed at power levels exceeding 89 mW. Although we did not find any significant negative effects of optical stimulation on the hearing function in these mice, based on the histology results further studies are necessary for optimization of the used parameters. © The Authors. Published by SPIE under a Creative Commons Attribution 4.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Significance: Worldwide, ∼460 million people suffer from disabling hearing impairment. Many of these patients are still not sufficiently supplied with currently available auditory technologies. Optical stimulation of the hearing organ offers a promising alternative for a new generation of auditory prostheses. Aim: To assess the biocompatibility margins of our laser pulse amplitude strategy in vitro, we designed a protocol and present the effects on normal human dermal fibroblasts, human chondrocytes, and human osteoblasts. Approach: Laser pulses of 532 nm were applied over 120 s using our laser pulse amplitude modulation strategy. We then assessed cell viability and cytotoxicity through fluorescence staining and quantitative polymerase chain reaction-analysis regarding 84 key player-genes for cytotoxicity and stress response. Results: The first in vitro biocompatibility margins for our stimulation parameters applied to cells of the peripheral hearing organ were between 200 and 223 mW (3348 J∕cm 2). After irradiation with a subphototoxic laser power of 199 mW (2988 J∕cm 2), only the fibroblasts showed a significant upregulation of GADD45G. Conclusion: Further studies are underway to optimize parameters for the optoacoustic stimulation of the auditory system. Our protocol and results on laser-tissue interactions can be useful for translational laser applications in various other irradiated biological tissues.

No abstract