Plontke Stefan K, Liebau Arne, Lehner Eric, Bethmann Daniel, Mäder Karsten, Rahne Torsten
Department of Otorhinolaryngology, Head and Neck Surgery, Martin Luther University Halle-Wittenberg, Halle, Germany.
Institute of Pathology, Martin Luther University Halle-Wittenberg, Halle, Germany.
Front Neurosci. 2022 Sep 20;16:892777. doi: 10.3389/fnins.2022.892777. eCollection 2022.
Intratympanic injections of glucocorticoids have become increasingly common in the treatment of idiopathic sudden sensorineural hearing loss (ISSHL). However, due to their fast elimination, sustained applications have been suggested for local drug delivery to the inner ear.
The study is based on a retrospective chart review of patients treated for ISSHL at a single tertiary (university) referral center. We included patients who were treated with a solid, biodegradable, poly(D,L-lactic-co-glycolic acid) (PLGA)-based drug delivery system providing sustained delivery of dexamethasone extracochlear into the round window niche ( = 15) or intracochlear into scala tympani ( = 2) for tertiary therapy of ISSHL in patients without serviceable hearing after primary systemic and secondary intratympanic glucocorticoid therapy. We evaluated the feasibility and safety through clinical evaluation, histological examination, and functional tests [pure-tone threshold (PTA), word recognition scores (WRS)].
With adequate surgical preparation of the round window niche, implantation was feasible in all patients. Histologic examination of the material in the round window niche showed signs of resorption without relevant inflammation or foreign body reaction to the implant. In patients where the basal part of scala tympani was assessable during later cochlear implantation, no pathological findings were found. In the patients with extracochlear application, average preoperative PTA was 84.7 dB HL (SD: 20.0) and 76.7 dB HL (SD: 16.7) at follow-up ( = 0.08). The preoperative average maximum WRS was 14.6% (SD: 17.9) and 39.3% (SD: 30.7) at follow-up ( = 0.11). Six patients (40%), however, reached serviceable hearing. The two patients with intracochlear application did not improve.
The extracochlear application of the controlled release system in the round window niche and - based on limited observations - intracochlear implantation into scala tympani appears feasible and safe. Due to the uncontrolled study design, conclusions about the efficacy of the treatment are limited. These observations, however, may encourage the initiation of prospective controlled studies using biodegradable controlled release implants as drug delivery systems for the treatment of inner ear diseases.
鼓室内注射糖皮质激素在特发性突发性感音神经性听力损失（ISSHL）的治疗中已变得越来越普遍。然而，由于其快速消除，有人建议持续应用以实现内耳的局部药物递送。
本研究基于对一家单一的三级（大学）转诊中心接受ISSHL治疗的患者进行的回顾性病历审查。我们纳入了那些接受基于聚（D，L - 乳酸 - 乙醇酸）（PLGA）的固体、可生物降解药物递送系统治疗的患者，该系统可将地塞米松持续递送至圆窗龛外耳（n = 15）或鼓阶内耳蜗内（n = 2），用于在初次全身和二次鼓室内糖皮质激素治疗后仍无有用听力的ISSHL患者的三级治疗。我们通过临床评估、组织学检查和功能测试[纯音阈值（PTA）、单词识别分数（WRS）]评估其可行性和安全性。
在对圆窗龛进行充分的手术准备后，所有患者的植入均可行。对圆窗龛内材料的组织学检查显示有吸收迹象，且对植入物无相关炎症或异物反应。在后期耳蜗植入时可评估鼓阶基部的患者中，未发现病理结果。在接受外耳应用的患者中，术前平均PTA为84.7 dB HL（标准差：20.0），随访时为76.7 dB HL（标准差：16.7）（P = 0.08）。术前平均最大WRS为最大WRS为14.6%（标准差：17.9），随访时为39.3%（标准差：30.7）（P = 0.）。然而，6名患者（40%）恢复到了有用听力。两名接受鼓阶内应用的患者没有改善。
在圆窗龛中外耳应用控释系统，以及基于有限观察的鼓阶内耳蜗植入似乎是可行和安全的。由于研究设计无对照，关于治疗效果的结论有限限。然而，这些观察结果可能会鼓励开展前瞻性对照研究，使用可生物降解的控释植入物作为治疗内耳疾病的药物递送系统。
