Department of Otolaryngology, Johns Hopkins Medical School, Baltimore, Maryland, USA.
Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA.
Otolaryngol Head Neck Surg. 2021 Jan;164(1):175-181. doi: 10.1177/0194599820934748. Epub 2020 Jun 30.
Labyrinthitis ossificans (LO) may occur following meningitis and, in cases where cochlear implantation is indicated, complicate electrode insertion. LO is critical to identify for successful cochlear implantation, and histopathology is more sensitive than imaging for identification of LO. Herein we utilize otopathologic techniques to study the timing and location of intracochlear tissue formation following meningitic labyrinthitis (ML).
Retrospective review.
Academic institution.
Temporal bone specimens with a history of bacterial ML were histologically evaluated. The location and extent of intracochlear tissue formation within the scala tympani (ST) and scala vestibuli (SV) were graded, and spiral ganglion neurons were counted.
Fifty-one temporal bones were identified: 32 with no intracochlear tissue formation, 9 with fibrosis alone, and 10 with LO. Fibrosis was identified as early as 1.5 weeks after ML, while ossification was found only in specimens that survived multiple years after ML. All LO cases showed ossification of the ST at the round window membrane (RWM) with continuous extension throughout the basal turn. Extent of SV ossification correlated with that in the ST but showed frequent isolated distal involvement of the cochlea. Spiral ganglion neuron counts were lower than those in age-matched controls.
In this human temporal bone study, we found that postmeningitic LO results in ossification at the RWM with continuous extension into the ST of the basal turn and variable involvement of the SV. Identification of a patent basal turn beyond RWM ossification of the ST should permit full electrode insertion.
Retrospective review.
耳硬化症（LO）可能发生在脑膜炎之后，如果需要进行耳蜗植入，它会使电极插入复杂化。LO 对于成功进行耳蜗植入至关重要，组织病理学比影像学更能准确识别 LO。在此，我们利用耳病理学技术研究脑膜炎性迷路炎（ML）后耳蜗内组织形成的时间和位置。
回顾性研究。
学术机构。
对有细菌性 ML 病史的颞骨标本进行组织学评估。对鼓阶（ST）和前庭阶（SV）内的耳蜗内组织形成的位置和程度进行分级，并计数螺旋神经节神经元。
共确定了 51 个颞骨标本：32 个无耳蜗内组织形成，9 个仅有纤维化，10 个有 LO。纤维化早在 ML 后 1.5 周即可发现，而骨化仅在 ML 后存活多年的标本中发现。所有 LO 病例均显示 RW 处 ST 骨化，基底回处连续延伸。SV 骨化的程度与 ST 相似，但耳蜗远端常孤立受累。螺旋神经节神经元计数低于年龄匹配的对照组。
在这项人类颞骨研究中，我们发现脑膜炎后 LO 导致 RW 处骨化，基底回 ST 处连续延伸，并伴有 SV 的不同程度受累。如果 RW 处 ST 骨化的基底回有通畅的通道，应该可以进行全电极插入。
回顾性研究。
