鼻咽癌的CT与MRI对比研究

目的:比较CT与MRI对鼻咽癌侵犯部位检出率的差别;评价MRI相对于CT对92分期产生的影响.方法:收集2003年1月至2004年6月收治、经病理证实的初诊鼻咽癌250例,所有病例同时具有治疗前鼻咽和颈部的CT及MRI资料.在CT和MRI上分别评价各个解剖部位的受侵犯情况.结合临床资料分别采用CT和MRI进行92分期.结果:MRI对于鼻咽超腔、茎突前间隙、口咽、咽后淋巴结、颅底骨质、海绵窦、鼻窦、颈椎和颞下窝等侵犯的检出率明显高于CT,有统计学意义.CT与MRI对于鼻腔、茎突后间隙侵犯及颈部淋巴结的检出差别无统计学意义.MRI使32.0%的T分期发生改变;11.6%的N分期发生改变;30.0%的临床分期发生改变.结论:MRI对于诊断鼻咽癌的超腔侵犯、颅底骨质、鼻窦、海绵窦受侵,以及咽后淋巴结转移要明显优于CT;而在颈部淋巴结转移的检出方面与CT结果一致.MRI主要影响鼻咽癌92分期的T分期;对N分期影响不大,临床分期的改变将有利于指引治疗方案的调整.

The Study of the Comparison of CT and MRI in Nasopharyngeal Carcinoma

Objective: To compare the diversity in tumor extension of nasopharyngeal carcinoma(NPC) by computerized tomography (CT) versus magnetic resonance imaging (MRI) and to evaluate theimpact on '92 staging system by using MR imaging. Methods: A total of 250 cases with NPC, histolog-ically diagnosed, received enhanced spiral CT and MRI scans of nasopharyngeal and cervical regionwere enrolled in this study. Clinical staging was scored according to '92 staging system based on both ofCT or MRI data and clinical information. Results: MRI was significantly superior to CT in the detectingof invasion of extra- nasopharyngeal cavity, anterior- styloid space, oropharynx, retropharyngeal lym-phatic metastasis, base of skull, cavernous sinus, nasal sinuses, cervical vertebra, and infratemporal fos-sa. There was no statistical difference between CT and MRI in the evaluation of involvement of nasalcavity, post- styloid space, and cervical lymph node metastasis. According to MRI data, 32.0% of Tclassification, 11.6%of N classification, and 30.0%of clinical stage were shifted. Conclusion: There isremarkable advantage of MRI in the detection of infiltration of extra- nasopharynx cavity, base of skull,nasal sinuses, cavernous sinus, and retropharyngeal lymphatic metastasis of NPC. The result of MRI isidentical with that of CT in metastasis of cervical lymph node. MRI mainly influences on T classifica-tion, and shows little impact on N classification of '92 stage system. The change of clinical stage willbenefit the adjustment of treatment strategy for NPC.