Ujihara Masaki, Kobayashi Masahito, Hirata Sachiko, Takabatake Kazuhiko, Wakiya Kenji, Fujimaki Takamitsu
Department of Neurosurgery, Saitama Medical University, Moroyama-machi, Saitama, Japan.
Neurosurgery. 2023 Sep 1;93(3):662-669. doi: 10.1227/neu.0000000000002469. Epub 2023 Mar 28.
Hearing impairment is an important complication of microvascular decompression (MVD). In patients after MVD, we have occasionally noted slight to moderate hearing deterioration at low frequencies that is difficult to detect using pure tone average.
To assess the incidence and features of low-frequency hearing impairment (LF-HI) after MVD and evaluate its associated factors.
This single-center, retrospective observational study assessed the audiometric outcome of 270 patients who underwent MVD between January 2015 and December 2020. Preoperative and postoperative hearing levels were compared for each frequency. LF-HI was defined as a hearing deterioration of ≥15 dB at 125, 250, or 500 Hz. The incidence, symptoms, and associated factors of LF-HI were analyzed.
Statistical analysis of the patients overall demonstrated slight but significant decreases in the hearing level after MVD at lower frequencies on both the operative and contralateral sides. Eighty-one patients (30.0%) had LF-HI: 49 on the operative side, 24 on the contralateral side, and 8 on both sides, while pure tone average was worsened in 5 patients (1.8%). Subjective symptoms, including hearing deterioration, ear fullness, tinnitus, and dizziness, developed in 10.4% of the patients with LF-HI but improved subsequently within several weeks. "Older age" and "operative side" were associated with LF-HI.
Decreases in lower-frequency hearing levels in both the ipsilateral and contralateral (nonoperative) ears were observed after trigeminal neuralgia and hemifacial spasm surgery. LF-HI does not cause permanent symptoms but may be a noteworthy phenomenon, possibly involved in the contralateral hearing loss encountered occasionally after other types of posterior cranial fossa surgery.
听力障碍是微血管减压术（MVD）的重要并发症。在接受MVD治疗的患者中，我们偶尔会注意到低频出现轻度至中度听力下降，使用纯音平均听阈难以检测到。
评估MVD术后低频听力障碍（LF-HI）的发生率和特征，并评估其相关因素。
这项单中心回顾性观察研究评估了2015年1月至2020年12月期间接受MVD治疗的270例患者的听力测量结果。比较每个频率的术前和术后听力水平。LF-HI定义为在125、250或500Hz频率处听力下降≥15dB。分析LF-HI的发生率、症状及相关因素。
对患者的统计分析总体显示，MVD术后手术侧和对侧较低频率的听力水平均有轻微但显著下降。81例患者（30.0%）出现LF-HI：手术侧49例，对侧24例，双侧8例，而纯音平均听阈恶化的有5例（1.8%）。LF-HI患者中有10.4%出现了包括听力下降、耳闷、耳鸣和头晕在内的主观症状，但随后在几周内有所改善。“年龄较大”和“手术侧”与LF-HI有关。
在三叉神经痛和面肌痉挛手术后，观察到同侧和对侧（非手术侧）耳朵的低频听力水平下降。LF-HI不会引起永久性症状，但可能是一个值得关注的现象，可能与其他类型的后颅窝手术后偶尔出现的对侧听力损失有关。
