摘要
背景与目的：中耳咽鼓管损害高峰发生在放疗后半年，并且在很多病例可持续终身，至今为止临床上尚无有效的治疗方法，寻求放射治疗中中耳鼓室及咽鼓管更好的保护仍是放射治疗医师面临的责任，在精确放疗技术应用逐渐普遍的今天，肿瘤周围正常组织和器官的保护受到越来越多的重视，但到目前为止，有关中耳放射损伤的研究报道极少。我们采用回顾性分析的方法，通过比较鼓室腔及骨性段咽鼓管剂量分布与放疗后分泌性中耳炎的发生率，评价在鼻咽癌3-D计划放射治疗中中耳功能保护的可能性，同时了解放疗后时问、化疗、T分期等因素对结果的影响。方法：40例80耳有完整听力学检查材料的鼻咽癌3-D计划放射治疗的患者进入此项研究。所有病例放疗前后均经耳部检查，电测听及声阻抗测听，放疗后随访时间为6～24个月。电测听以500，1000，2000，4000Hz听阈平均值计算气骨导差，声阻抗根据鼓窒图分为A、B、C3型，A型为正常鼓室图，B型为中耳鼓室积液，C型为咽鼓管功能不良。结果：79耳符合声阻抗分析条件。放疗后62％耳与放疗前保持不变，13％耳得到改善，25％耳恶化。鼓室腔及骨性段咽鼓管剂量分布在恶化耳与其他各组耳之间比较差异有显著性。80耳电测听分析结果，放疗后无变化耳58％，改善耳12％，恶化耳30％。分析剂量因素对声阻抗结果的影响，恶化组的鼓室腔及骨性段咽鼓管平均受照剂量为（5379.81±706，01）cGy，不变组的平均受照剂量为（4735，72±812．30）cGy，改善组的平均剂量为（4652．86±809．78）cGy；分析剂量因素对电测听结果的影响，恶化组的中耳及骨性咽鼓管平均受量为（5229．38±778．11）cGy，不变组的半均受量为（4719．64±744．82）cGy，改普组的平均剂量为（4702．38±922，21）cGy。统计分析发现3组的剂量差异有
Background and purpose： The eustachian tube （ET） function is poorest 6 months after irradiation and may last for life. No effective treatment method has been present until now, h is still a great duty for physician to find methods for better protection of ET and middle ear cavity during radiotherapy, As new radiotherapy techniques were used, more articles had reported the protection of normal structures from radiation-induced damage, but few mentioned the protection of middle ear function, This study is a retrospective analysis of patients of nasopharyngeal carcinoma, which will evaluate the relationship between the incidence of radiation-induced otitis media with effusion （OME） and the dose distribution over the middle ear cavity and ET. The possibility of middle ear thnction preservation in 3-D planning system-based radiotherapy in the treatment of nasopharyngeal carcinoma was discussed. Other related factors including the time after radiotherapy, chemotherapy and T stage were also analyzed at the same time. Methods： 40 patients with nasopharyngeal carcinoma undergoing curaitive 3-D radiotherapy RT were retrospectively analyzed. All patients underwent hearing tests including pure tone audiometry and impedance audiometry before and after RT. Tim time after RT was 6-24 months. All patients were tumor-free in at follow-up and the age had to be under 55 years. The mean value of bone and air conduction for pure tone audiometry at 500, 1 000, 2 000, and 4 000 Hz were used as endpoints, the hearing threshold was evaluated according to the gap change between air conduction and bone conduction（ A-B gap）. The difference of A-B gap before and after RT was compared for each ear.The results of impedance audiometry were divided into three types,type A tympanogram was normal,type B tympanogram showed the existence of fluid in middle ear cavity.type C tympanogram showed negative pressure in the middleeare cavity,the tympanogram change before and after RT were also compared for each ear.Results：Of the 40 patie
出处
《中国癌症杂志》
CAS
CSCD
2006年第6期503-507,共5页
China Oncology
关键词
鼻咽癌
放射治疗
三维计划
放射性中耳炎
电测听
声阻抗
nasopharyngeal carcinoma
radiotherapy
3-D planning system
otitis media with effusion
pure tone audiometry
impedance audiometry.
