Deutsch Philipp, Bankstahl Jens P, Mamach Martin, Willmann Michael, Bengel Frank M, Lenarz Thomas, Berding Georg, Scheper Verena, Schwieger Jana
Department of Nuclear Medicine, Hannover Medical School, Hannover, Germany.
Cluster of Excellence Hearing4all, Hannover Medical School and University of Oldenburg, Hannover, Germany.
Front Immunol. 2025 Jul 10;16:1601742. doi: 10.3389/fimmu.2025.1601742. eCollection 2025.
After cochlear implantation, molecular processes at the electrode-nerve interface significantly influence the variability in clinical outcomes. The present study investigates molecular processes in a guinea pig model of cochlear implant (CI) using positron emission tomography/computed tomography (PET/CT) and correlates the imaging findings with histological analyses.
Animals were examined with PET in the 3 weeks and 9-12 months post-implantation using the inflammation marker [F]FDG and, at the later time points, [Ga]FAPI-46 as a marker for fibrosis. Tracer accumulation in the cochlea was determined from PET imaging based on the co-registered CT. Nine animals (seven with unilateral CI) were included. Uptake in non-implanted cochleae served as reference. Tissue growth around the implant was evaluated histologically.
Post-implantation, [F]FDG uptake was significantly increased when pooling early and late in investigation time points, while after 1 year, [Ga]FAPI-46 uptake was increased inside the cochlear. Cochlear volumes measured by CT did not show significant differences between compared groups. Tissue growth around the implant was observed in all animals, with a trend toward increased growth associated with insertion depth. However, no clear correlation was observed between the extent of tissue growth and the uptake intensities of FDG and FAPI.
The data indicate that increased accumulation of PET biomarkers in the cochlea after implantation can be detected in guinea pigs using a dedicated PET/CT. Given the high resolution of current clinical PET/CT devices, this method is expected to be suitable for use in patients, particularly for assessing the effect of anti-inflammatory or anti-fibrotic therapies.
人工耳蜗植入后，电极 - 神经界面的分子过程会显著影响临床结果的变异性。本研究使用正电子发射断层扫描/计算机断层扫描（PET/CT）在豚鼠人工耳蜗（CI）模型中研究分子过程，并将成像结果与组织学分析相关联。
在植入后的3周和9 - 12个月，使用炎症标志物[F]FDG对动物进行PET检查，在后期时间点使用[Ga]FAPI - 46作为纤维化标志物。基于配准的CT从PET成像中确定示踪剂在耳蜗中的积聚。纳入9只动物（7只单侧CI）。未植入耳蜗的摄取作为对照。通过组织学评估植入物周围的组织生长情况。
植入后，在研究时间点早期和晚期合并时，[F]FDG摄取显著增加，而在1年后，[Ga]FAPI - 46在耳蜗内的摄取增加。CT测量的耳蜗体积在比较组之间未显示出显著差异。在所有动物中均观察到植入物周围的组织生长，且组织生长有随插入深度增加的趋势。然而，在组织生长程度与FDG和FAPI的摄取强度之间未观察到明显的相关性。
数据表明，使用专用的PET/CT可以在豚鼠中检测到植入后耳蜗中PET生物标志物的积累增加。鉴于当前临床PET/CT设备的高分辨率，预计该方法适用于患者，特别是用于评估抗炎或抗纤维化治疗的效果。
