Current surgical microscopes suffer from inherent constraints in achievable viewing angles and require manual interaction to control settings. Overcoming these limitations may provide benefits for ... 背景：当前的外科显微镜在可实现的视角方面受到固有的限制, 并且需要手动干涉来控制设置。克服这些限制可能会为耳科手术带来好处。 目的：我们在此提出对一种新型的商业手术显微镜的首次可行性和可用性评估。该显微镜具有虚拟-现实界面和对机器人安装的3D摄像机的免提控制。 材料和方法：体外可行性测试是根据普通的耳科手术程序在人尸头部样品中进行的。可用性指标是从反馈表中获得的。在第一个临床病例中, 该设备...

Background/Objectives: Electrocochleography (ECochG) is a promising tool to monitor preservation of cochlear structures and function during cochlear implant (CI) surgery. However, the interpretation of ECochG signal changes during insertion of the CI electrode array remains controversial. This study investigates the influence of the degree and localization of cochlear trauma on ECochG signal changes using a mouse model. Methods: C57BL/6J-Crl1 mice underwent intracochlear ECochG recordings during the insertion of a platinum–iridium electrode. Results: In case of grade 1 and 2 cochlear trauma, as determined by post-mortem histological analysis, we found that a reduction in intracochlear cochlear microphonic (CM) amplitude correlates more significantly with the location of the trauma than with its severity. The more basally a trauma is located, the larger the CM amplitude drop. Furthermore, the results revealed that grade 1 or 2 trauma was detectable through ECochG before more severe trauma developed. Conclusions: These findings suggest that intracochlear ECochG can serve as a reliable intraoperative tool for detecting early and possibly reversible cochlear trauma, preventing more severe damage and aiding hearing preservation. The results emphasize the need for a nuanced interpretation of CM signal drops, considering trauma location and cochlear structure integrity at the site of trauma and apical to it.

While fresh cadaveric temporal bones are preferable in middle-ear research, limited availability and strict ethical regulation often require the use of fresh-frozen temporal bones as an alternative. Previous studies have shown that freezing and thawing can alter mechanical properties of soft tissues like ligaments, muscles, and joints, yet the effect of freezing on middle-ear sound transmission has not been fully revealed. This study aims to investigate the effects of freezing by comparing the middle-ear transfer function (METF) between fresh and fresh-frozen temporal bones. Data of 101 human temporal bones (57 fresh and 44 fresh-frozen) were analyzed. The magnitudes of the METF between 125 and 6000 Hz were averaged frequency-wise and compared between both groups. Further, each frequency-response curve was fitted with a rational polynomial, and all fitted curves were averaged for analysis of shape-preserving information such as the location of natural frequencies. The average METF magnitude was considerably lower for fresh-frozen temporal bones in frequencies below 3000 Hz with differences of up to 7 dB. Shape-preserving analysis of frequency responses revealed two natural frequencies at 900 and 3487 Hz for fresh and at 988 and 3180 Hz for fresh-frozen temporal bones, with no statistically significant differences between fresh-frozen and fresh temporal bones. With only a slight reduction in METF magnitude at low frequencies compared to large interindividual variabilities, fresh-frozen temporal bones can be considered as an alternative to fresh temporal bones. However, stiffening of middle-ear structures needs to be taken into account when using fresh-frozen temporal bones.