Minakata Toshiya, Inagaki Akira, Sekiya Shinji, Murakami Shingo
Department of Otolaryngology, Nagoya City University, Graduate School of Medical Sciences and Medical School, Aichi, Japan.
Department of Otolaryngology, Nagoya City University, Graduate School of Medical Sciences and Medical School, Aichi, Japan.
Auris Nasus Larynx. 2019 Oct;46(5):687-695. doi: 10.1016/j.anl.2018.12.015. Epub 2019 Jan 7.
In Ramsay Hunt syndrome, contrast enhancement of magnetic resonance (MR) imaging seen in the affected facial nerve in the majority of cases, but its clinical significance has not been well investigated to date. The aim of this study was to elucidate the clinical significance of this imaging sign by quantitively investigating the correlation between the signal increase and swelling of the facial nerve. We also investigated the temporal change in this sign and its correlation with recovery.
We retrospectively evaluated swelling of the facial nerve in 16 patients with severe Ramsay Hunt syndrome who underwent both contrast-enhanced magnetic resonance imaging and facial nerve decompression surgery via a transmastoid approach alone or in combination with a middle cranial approach. All the patients had a Yanagihara score of ≤8 points and facial nerve degeneration of ≥90% confirmed by either a nerve excitability test or electroneurography. Swelling of the facial nerve was evaluated intraoperatively using a 4-point grading system.
A significant correlation was observed between contrast enhancement on T1-weighted images and facial nerve swelling in the labyrinthine segment, geniculate ganglion, and pyramidal segment (P = 0.030, P = 0.018, and P = 0.037, respectively). Furthermore, the contrast enhancement increased significantly as more time elapsed after the onset of facial palsy (mean ± standard error, 14.7 ± 2.3 days, range, 5-42 days) in the geniculate ganglion and pyramidal segment (correlation coefficient, 0.546 and 0.689, P = 0.022 and P = 0.002, respectively). Patients with good recovery (Yanagihara score of ≥36) showed significantly lower contrast enhancement in the tympanic and mastoid segments (P = 0.021 and 0.020, respectively) than those who with poor recovery.
In particular segments of the facial nerve, contrast enhancement on T1-weighted image correlated with facial nerve swelling and recovery. These observations underscore the clinical significance of contrast enhancement on T1-weighted images in patients with Ramsay Hunt syndrome.
在拉姆齐·亨特综合征中，多数病例受累面神经在磁共振成像（MR）上可见强化，但其临床意义至今尚未得到充分研究。本研究的目的是通过定量研究面神经信号增强与肿胀之间的相关性，阐明这一影像学表现的临床意义。我们还研究了该表现的时间变化及其与恢复情况的相关性。
我们回顾性评估了16例重度拉姆齐·亨特综合征患者的面神经肿胀情况，这些患者均接受了对比增强磁共振成像检查，并通过单纯经乳突入路或联合中颅窝入路进行了面神经减压手术。所有患者的柳原评分均≤8分，且经神经兴奋性试验或神经电图证实面神经变性≥90%。术中使用4分制分级系统对面神经肿胀进行评估。
在T1加权图像上的强化与面神经在迷路段、膝状神经节和锥段的肿胀之间存在显著相关性（分别为P = 0.030、P = 0.018和P = 0.037）。此外，在膝状神经节和锥段，面神经麻痹发作后时间越长，强化越显著（平均值±标准误，14.7±2.3天，范围5 - 42天）（相关系数分别为0.546和0.689，P = 0.022和P = 0.002）。恢复良好（柳原评分≥36）的患者在鼓室段和乳突段的强化明显低于恢复不佳的患者（分别为P = 0.021和0.020）。
在面神经的特定节段，T1加权图像上的强化与面神经肿胀及恢复情况相关。这些观察结果强调了T1加权图像强化在拉姆齐·亨特综合征患者中的临床意义。
