Ito K, Kurita H, Sugasawa K, Okuno T, Mizuno M, Sasaki T
Department of Otolaryngology, Faculty of Medicine, University of Tokyo, Japan.
Arch Otolaryngol Head Neck Surg. 1996 Nov;122(11):1229-33. doi: 10.1001/archotol.1996.01890230075014.
To evaluate the neuro-otological complications in patients after radiosurgery for acoustic neurinomas.
Inception cohort, retrospective study.
University hospital.
A consecutive sample of 46 patients with acoustic neurinomas who underwent unilateral gamma knife radiosurgery at the University of Tokyo, Japan, between June 1990 and June 1994 were followed up by otolaryngologists for more than 3 months.
Gamma knife stereotactic radiosurgery.
Neuro-otological examinations including pure tone audiometry, auditory brain stem response, and caloric test.
Tumor growth occurred in 2 patients (4.3%). Seven (18%) of the 38 patients with preserved hearing of any extent became deaf within 1 year. In cases of gradual hearing loss, the average deterioration rate was approximately 8 dB per year. Abnormalities of auditory brain stem response preceded deafness in 2 patients. Caloric response, preserved before treatment in 13 patients, disappeared 4 to 13 months after treatment (median, 8 months) in 9 (69%) of them, whereas their hearing was preserved. Delayed facial palsy and persistent trigeminal neuropathy occurred in 10 (22%) and 7 (15%) of the 46 patients, respectively. Severe facial palsy tended to persist.
The rates of neuro-otological complications of radiosurgery are almost comparable with those previously reported from other institutions. The deafness within 1 year after treatment might be attributed to a lesion in the cochlear nerve. Hearing loss did not parallel vestibular function loss. The persistent severe facial palsy contrasts with previously reported findings. Considering the serious facial nerve complications that occurred in some of our patients, further study to disclose the risk factors for neurological dysfunction would be needed for radiosurgery to become a true, safe alternative to microsurgery.
评估听神经瘤患者接受放射外科治疗后的神经耳科并发症。
起始队列，回顾性研究。
大学医院。
1990年6月至1994年6月期间在日本东京大学接受单侧伽玛刀放射外科治疗的46例听神经瘤患者的连续样本，由耳鼻喉科医生随访超过3个月。
伽玛刀立体定向放射外科治疗。
神经耳科检查，包括纯音听力测定、听性脑干反应和冷热试验。
2例患者（4.3%）出现肿瘤生长。38例有任何程度听力保留的患者中，7例（18%）在1年内失聪。在听力逐渐丧失的病例中，平均恶化率约为每年8分贝。2例患者听性脑干反应异常先于失聪出现。13例治疗前冷热反应正常的患者中，9例（69%）在治疗后4至13个月（中位数为8个月）冷热反应消失，而他们的听力得以保留。46例患者中分别有10例（22%）和7例（15%）发生迟发性面神经麻痹和持续性三叉神经病变。严重面神经麻痹往往持续存在。
放射外科治疗的神经耳科并发症发生率与其他机构先前报告的发生率几乎相当。治疗后1年内的失聪可能归因于蜗神经病变。听力丧失与前庭功能丧失不平行。持续性严重面神经麻痹与先前报告的结果不同。考虑到我们部分患者发生的严重面神经并发症，为使放射外科治疗成为显微外科真正安全的替代方法，需要进一步研究以揭示神经功能障碍的危险因素。
