弥散成像技术在软组织恶性肿瘤和炎症性病变鉴别中的应用价值

Application value of diffusion weighted imaging in the Differential diagnosis between soft tissue malignant tumors and inflammatory lesions

目的探讨弥散加权成像(DWI)技术在软组织恶性肿瘤和炎症性病变鉴别中的应用价值。方法对42例软组织包块患者,应用GEsigna 1.5T核磁扫描仪进行常规MRI检查和增强扫描,DWI采用SE-EPI技术,所有患者均经手术治疗或穿刺诊断,经病理结果或其他资料证实,对所有患者病变部位进行ADC值测量,并对ADC值进行比较研究。结果共检测出软组织肿块45个,其中有32例经病理证实,其余10例患者结合其他资料得到证实。恶性肿瘤患者23例,其中脂肪肉瘤8例,纤维肉瘤7例,腺泡状软组织肉瘤3例,滑膜肉瘤3例,恶性纤维组织细胞瘤2例,均表现为不规则的软组织包块,且周围边界不清晰,信号不均匀,未强化低信号区增强扫描无强化,DWI低信号。脓肿19例,其中细菌性脓肿9例,结核性脓肿8例,滑膜炎2例,均表现为肌间隙和关节囊长T1、T2信号,周围软组织明显肿胀,脓肿壁增强扫描均匀强化,而脓肿腔则无明显强化现象发生。脓肿在b值下弥散序列呈高信号15例,等信号4例;而肿瘤实质部分呈高信号19例,等信号4例。ADC值差异显著(t=4.28,P<0.05)。结论弥散成像技术能够结合常规序列帮助临床医生对软组织恶性肿瘤和软组织炎症性病变进行鉴别诊断,不仅减少了不必要的创伤性治疗,还在一定程度上节省了医疗资源,值得临床推广应用。

Objective To study the application value of diffusion weighted imaging technique in the differential diagnosis between soft tissue malignant tumors and inflammatory lesions. Methods Forty-two cases of patients with soft tissue mass underwent conventional MR/ scanning and enhanced scanning by GEsigna 1.5T magnetic resonance scanner, with DWI using SE-EPI technology. All patients were diagnosed by operation or biopsy. All patients＇ ADC value was measured. Results The soft tissue masses were detected in 45 cases, of which 32 cases were confirmed by pathology, and the other 10 patients was confirmed in combination with other data. Of all 42 patients, 23 were diagnosed as malignant tumor, including 8 cases of liposarcoma, 7 cases of fibmsarcoma, 3 cases of alveolar soft tissue sarcoma, 3 cases of synovial sarcoma, and 2 cases of malignant fibrous histiocytoma, and all were showed as irregular soft tissue mass, unclear surrounding boundary, uneven signal, no enhancement in unenhanced low signal zone, and low signal in DWI ; 19 were abscess, including 9 cases of bacterial abscess, 8 cases of tuberculous abscess, and 2 patients with synovitis, and all were showed as long T1, T2 signal in muscle gap and joint capsule, the surrounding soft tissue swelling, and abscess wall enhancement by homogeneous enhancement, but no obvious enhancement in the abscess cavity. Abscess in the b value diffusion sequences was showed high signal in 15 cases, equal signal in 4 cases; while the solid part of the tumors showed high signal in 19 cases, equalsignal in 4 cases, with a significant different ADC value between them （ t = 4. 28, P 〈 0. 05 ）. Conclusion Diffusion weighted imaging techniques in combination with conventional sequences can help clinicians in the differential diagnosis of malignant soft tissue tumor and soft tissue inflammation. It can not only reduce unnecessary traumatic treatment, but also to a certain extent, save medical resources, indicating it is worthy of clinical application.