滑动多层技术的二维快速小角度激发成像序列在直肠癌腹部转移诊断中的应用价值

The value of fast low-angle shot 2-dimensional sequence with sliding multi-slice technique in the detection of abdominal metastasis of rectal cancer

目的探讨采用滑动多层（SMS）技术的二维快速小角度激发成像（FLASH-2D）序列在直肠癌腹部转移灶诊断中的价值。方法由2名放射科医师回顾性分析15例经手术病理证实的直肠癌患者资料，15例均接受SMSFLASH-2DMRI和多层螺旋CT（MSCT）检查（4例进行了2次检查）。以SMS和MSCT及6个月内所有随诊检查的最终一致意见作为疾病诊断的参考标准。采用Kappa。检验评价2种检查方法对于直肠癌肝转移、淋巴结转移和骨转移诊断的一致性和不同观察者对疾病诊断的一致性，并比较2种方法对各种转移病灶诊断的灵敏度。结果2名医师采用SMS技术都发现了60个病灶中的56个转移灶，灵敏度均为93．33％（56／60）；采用MSCT均发现了50个病灶，灵敏度均为83．33％（50／60）。对于肝转移灶的诊断，2名医师采用SMS诊断的灵敏度分别为97．44％（38／39）和100％（39／39）；采用MSCT诊断的灵敏度均为100％（39／39）。对于淋巴结转移的诊断，SMS诊断的灵敏度为85．71％（12／14）和71．43％（10／14）；MSCT分别为78．57％（11／14）和71．43％（10／14）。对骨转移灶的诊断，SMS的灵敏度分别为85．71％（6／7）和100％（7／7）；MSCT分别为0（0／7）和14．29％（1／7）。结论SMSFLASH-2D序列在对直肠癌肝转移和淋巴结转移诊断上有和MSCT相同的能力，对于骨转移灶的诊断则明显较MSCT敏感。

Objective To evaluate the potential of a sliding multi-slice （SMS）fast low-angbe shot 2-dimensional（FLASH-2D） sequence for abdominal lesion detection in patients with rectal cancer. Methods Nineteen paired SMS MRI（FLASH-2D sequnce） and MSCT examinations of the whole abdomen and pelvis in 15 patients （four of them were examined twice） with rectal cancer were retrospectively analyzed by two radiologists. While the lesion-based agreement between the two methods and the diagnostic agreement between two observers were tested by means of Kappa statistics, the sensitivities of SMS FLASH-2D and MSCT to detect liver metastases, lymph node metastases and bone metastases were calculated. Standard of reference consisted of a consensus evaluation of SMS, MSCT and all available follow-up examinations after a period of 6 months. Results Using SMS FLASH-2D cumulatively, both observers detected 56 of all 60 lesions respectively resulting in same sensitivities of 93.33% （56/60）. Using MSCT, both observers detected 50 lesions, resulting in same sensitivities of 83.33% （50/60） respectively. The sensitivities of SMS FLASH-2D to detect hepatic metastases were 97.44% （38/39） and 100% （39/39） for both observers respectively, compared to 100 % （39/39）and 100% （39/39）for MSCT. The sensitivities for lymph node metastases were 85.71% （12/14） and 71.43% （10/14） for SMS FLASH-2D compared to 78.57% （11/14 ） and 71.43% （10/14） for MSCT. The sensitivities for bone metastases were 85.71% （6/7） and 100% （7/7） for SMS FLASH 2D compared to 0 （0/7） and 14. 29% （1/7） for MSCT. Conclusion SMS FLASH- 2D imaging and MSCT exhibit equal ability of detecting lymph node and liver metastases, but SMS FLASH 2D seems better than MSCT in dectecting bone metastases.