BC Rotary Hearing and Balance Centre at St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.
Department of Radiology, St. Paul's Hospital, University of British Columbia, Vancouver, BC, Canada.
Clin Otolaryngol. 2019 Nov;44(6):1017-1025. doi: 10.1111/coa.13432. Epub 2019 Oct 2.
The underlying pathophysiology of idiopathic sudden sensorineural hearing loss (ISSNHL) is still unknown. However, an increasing number of observational studies report intralabyrinthine signal alterations in patients with ISSNHL using three-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging (MRI). These findings warrant a meta-analysis.
To conduct a meta-analysis assessing the value of 3D-FLAIR MRI in identifying possible underlying labyrinthine pathophysiologic mechanisms and prognostication in patients with ISSNHL.
Two reviewers independently searched the Pubmed, Embase and Cochrane Library from inception until October 10, 2018 and evaluated eligibility based on titles and abstracts of all retrieved studies. All studies reporting on 3D-FLAIR imaging in ISSNHL were included. Subsequently, the full text of eligible studies were evaluated.
Adhering to the MOOSE guideline, two independent reviewers extracted data, assessed risk of bias and evaluated the relevance and quality of evidence. Data on the number of patients and events were extracted and hearing levels were converted to standardised mean differences (SMD) for conducting meta-analyses. Random effects models for meta-analyses were applied.
Eight observational studies met our inclusion criteria (n = 638 patients). In 29%, high signal intensity was found on 3D-FLAIR imaging, suggesting labyrinthine pathology (labyrinthitis [79%], intralabyrinthine haemorrhage [21%]). High signal intensity on 3D-FLAIR was associated with poorer hearing (SMD: 14 dB, 95% CI 5.67-22.94) and vertigo (RR: 1.92, 95% CI 1.16-3.17) at baseline. Multivariate analyses demonstrated that patients with high 3D-FLAIR signal intensity had 21 dB lower final hearing pure-tone averages (SMD: 21 dB, 95% CI 9.08-33.24).
Three-dimensional fluid-attenuated inversion recovery MR imaging can identify an underlying labyrinthine condition in up to 29% of patients with sudden hearing loss in whom previously no cause could be identified. Their final pure-tone averages are more than 20 dB worse than 3D-FLAIR-negative patients, suggesting more severe labyrinthine damage. Findings such as these may contribute to our understanding of pathophysiologic mechanisms of ISSNHL.
特发性突发性聋（ISSNHL）的潜在病理生理学机制尚不清楚。然而，越来越多的观察性研究报告称，使用三维液体衰减反转恢复（3D-FLAIR）磁共振成像（MRI）可在 ISSNHL 患者中发现内淋巴管信号改变。这些发现需要进行荟萃分析。
进行荟萃分析，评估 3D-FLAIR MRI 在识别 ISSNHL 患者潜在的内耳病理生理机制和预后方面的价值。
两位审稿人独立检索了 Pubmed、Embase 和 Cochrane Library，从成立到 2018 年 10 月 10 日，并根据所有检索到的研究的标题和摘要评估了入选标准。所有报告 ISSNHL 3D-FLAIR 成像的研究均被纳入。随后，评估了合格研究的全文。
两位独立的审稿人按照 MOOSE 指南提取数据，评估偏倚风险，并评估证据的相关性和质量。提取患者数量和事件的数据，并将听力水平转换为标准化均数差（SMD）以进行荟萃分析。应用随机效应模型进行荟萃分析。
有 8 项观察性研究符合我们的纳入标准（n=638 例患者）。在 29%的患者中，3D-FLAIR 成像显示高信号强度，提示内耳病变（迷路炎[79%]，内淋巴管出血[21%]）。3D-FLAIR 上的高信号强度与听力较差（SMD：14dB，95%CI 5.67-22.94）和基线时眩晕（RR：1.92，95%CI 1.16-3.17）相关。多变量分析表明，高 3D-FLAIR 信号强度的患者最终纯音平均听力损失低 21dB（SMD：21dB，95%CI 9.08-33.24）。
在先前无法确定病因的突发性听力损失患者中，高达 29%的患者可通过 3D-FLAIR 磁共振成像识别潜在的内耳病变。他们的最终纯音平均听力比 3D-FLAIR 阴性患者差 20dB 以上，提示内耳损伤更严重。这些发现可能有助于我们理解 ISSNHL 的病理生理机制。
