CT与MRI对鼻咽癌分期影响的研究

[目的]比较MRI与CT对鼻咽癌侵犯范围检查的差异性和对T分期的影响。[方法]回顾性分析84例治疗前同时或短时间内（不超过2周）行CT和MRI检查并经病理活检证实是鼻咽癌的患者资料，用χ^2检验比较两种检查方法对各解剖部位的检出率。按’92鼻咽癌分期标准，分别以CT加临床体检和MRI加临床体检对患者进行临床分期．用χ^2检验比较这两种方法划分的各期病例数的分布情况。[结果]CT和MRI诊断颅底骨质破坏的发生率分别为11．9％和41．7％，两种检查方法比较有显著性差异（χ2=18．970，P±0．000）。CT和MRI诊断海绵窦受侵犯的发生率分别为8.3％和20．2％，两种检查方法比较差异有显著性（χ2=4．861，P=0．027）。对于T分期，用CT和MRI划分的各期病例数分布情况比较有显著性差异（χ2=16．416，P=0．001）。有31例（36．9％）在CT与MRI之间发生了T分期改变，MRI所划分的中晚期患者（Ⅲ期和Ⅳa期）比CT增多。[结论]MRI对鼻咽癌侵犯颅底骨质和海绵窦的检出率高于CT。MRI可使鼻咽癌的T分期升级。

Impact of Computed Tomography and Magnetic Reso-nance Imaging on Staging for Nasopharyngeal Carci-noma

[Purposel To compare the differences between computed tomography （CT） and magnetic resonance imaging（MRI） on defecting disease extent and the effect of T staging in nasopharyngeal carcinoma （NPC）. [Methods] Eighty-four cases with nasopharyngeal carcinoma pathologically proved who performed CT and MRI examination at the same time or during a short time （no more than two weeks） before the treatment were retrospectively analyzed. χ2 test was used to compare the detective rate of every anatomical position by these two kinds of imaging methods. According to the ＇92 staging standard of NPC, the patients were staged by CT plus clinical examination and by MRI plus clinical examination. χ2 test was used to compare the composition of various stages divided by these two kinds of imaging methods. [Results ] The incidence rates of cranial bone damage diagnosed by CT and MRI were 11.9% and 41.7% respectively, with statistical significance（χ2=18.970, P=0.000）. The incidence rates of encroachment of cavernous sinus diagnosed by CT and MRI were 8.3% and 20.2% respectively, which was of statistical significance （χ2=4.861,P=0.027）. To the T staging, the composition of various stages divided by these two kinds of imaging methods was of statistical significance （χ2=16.416, P=0.001）.There were 31 patients （36.9%） whose T stages changed between CT and MRI, while there were more advanced stage patients （Ⅲ and Ⅳa） diagnosed by MRI than those by CT. [Conclusion] The detecting rates of cranial bone damage and encroachment cavernous sinus detected by MRI are higher than those by CT. MRI can elevate the T staging for NPC.