ObjectiveTo discuss the value of diffusion weighted imaging (DWI) in the diagnosis of placenta increta. MethodsThe clinical data of 42 patients with placenta increta admitted to Sichuan Provincial Hospital for Women and Children between May 2012 and January 2014 were retrospectively analyzed. All the patients were examined by prenatal magnetic resonance scans and DWI scans for subsequent comparison between ADC of the local convex placental region and ADC of the normal placental region and between the results of the two imaging methods. ResultsADC of the implantation area was significantly different from that of the normal placenta, so it could be used as a quantitative index. DWI had a higher sensitivity of diagnosis than conventional MRI. ConclusionCompared with conventional magnetic resonance imaging, DWI is more valuable in the clinical diagnosis of placenta increta, which provides a reliable basis for clinical treatment.
Objective To investigate the feasibility of imaging of bone marrow mesenchymal stem cells (BMMSCs) labeled with superparamagnetic iron oxide(SPIO) transplanted into coronary artery in vivo using magnetic resonance imaging (MRI), and the redistribution of the cells into other organs. Methods BMMSCs were isolated, cultured from bone marrow of Chinese mini swine, and double labeled with SPIO and CMDiI(Cell TrackerTM C-7001). The labeled cells were injected into left anterior descending coronary artery through a catheter. The injected cells were detected by using MRI at 1 week,3weeks after transplantation. And different organs were harvested and evaluated the redistribution of transplanted cells through pathology. Results The SPIO labeled BMMSCs injected into coronary artery could be detected through MRI and confirmed by pathology and maintained more than 3 weeks. The SPIO labeled cells could be clearly imaged as signal void lesions in the related artery. The pathology showed that the injected cells could be distributed into the area of related artery, and the cells injected into coronary artery could be found in the lung, spleen, kidney, but scarcely in the liver, the structures of these organs remained normal. Conclusion The SPIO labeled BMMSCs injected into coronary artery can be detected by using MRI, the transplanted cells can be redistributed into the non-targeted organs.
Objective To investigate the effects on myocardial perfusion of simultaneous antegrade/retrograde cardiopiegia （SARC） through a single coronary artery and coronary sinus （CS）. Methods SARC was conducted in isolated pig hearts through CS in conjunction with the left anterior descending （LAD）, the left circumflex （LCX）, or the right coronary artery （RCA） respectively. After injecting magnetic resonance （MR） contrast agent （gadolinium diethyienetriamine pentaacetic acid, Gd-DTPA） into arterial or venous route, the distribution of Gd-DTPA with magnetic resonance imaging（MRI） was monitored and the effluent from the venting coronary arteries to assess the efficacy of SARC for myocardial perfusion was measured. Results Injection of Gd-DTPA into a perfusing artery during SARC resulted in increased signal intensity not only in the territory of the perfusing artery but also in the areas normally served by the other two venting coronary arteries （including the right ventrieuiar free wall）. With Gd DTPA given into the CS during SARC, the myocardium in the territories of the two venting coronary arteries was lightened. Signal intensity of the myocardium in the perfusing artery territory and right ventricuiar free wall remained unchanged. Moreover, a significant amount of effluent was collected from the venting coronary arteries during SARC： the LAD 10.5-17.7 ml/min; LCX 9.7-15.2 ml/min, and RCA 4.7-7.8 ml/min. Conclusion SARC through a single coronary artery and CS can provide homogeneous perfusion to the entire heart and is sufficient to prevent ischemic injury in the myocardium normally supported by the venting coronary arteries.
目的 根据MRI颈脊髓信号异常平面决定椎板切除减压范围，观察侧块螺钉固定结合不同范围全椎板切除减压治疗在颈脊髓损伤的临床疗效。 方法 2008年9月-2011年12月收治颈脊髓损伤患者16例。其中男10例，女6例，高处坠落伤5例，车祸11例，MRI显示脊髓损伤信号改变波及2个节段3例，3个节段9例，4个节段4例，椎间盘损伤变性12例，椎间盘轻度突出4例，均诊断为颈脊髓损伤伴高位截瘫，均行后路手术治疗。根据手术方式将16位患者分为观察组（9例）及对照组（7例），均采用后路侧块螺钉固定结合全椎板切除减压治疗，观察组减压范围以MRI提示颈脊髓信号异常为中心，对照组减压范围均为颈3～颈7。比较两组治疗前后的ASIA评分改变。 结果 16例患者均得到随访，随访10～48个月，平均17个月，脊髓神经恢复功能按照ASIA运动评分，平均增长值：对照组（42.75 ± 12.56）高于观察组（20.52 ± 11.60），差异有统计学意义（P＜0.05）。观察组患者ASIA分级分布：术前A级4例，B级4例，C级1例，末次家庭随访时A级4例，B级3例，C级2例；对照组术前A级3例，B级3例，C级1例，末次家庭随访时A级2例，B级1例，C级2例，D级2例，对照组ASIA分级术前与术后比较，差异有统计学意义（P＜0.05）；观察组ASIA分级术前与术后比较，差异无统计学意义（P＞0.05）；比较两组ASIA分级改善率，对照组明显优于观察组（P＜0.05）。 结论 根据MRI提示的颈脊髓信号异常平面决定侧块螺钉固定及颈椎板切除范围治疗颈脊髓损伤疗效不佳，减压范围扩大至颈3-颈7疗效较好。
Objective To evaluate the clinical value of cardiac MRI for the diagnosis of viral myocarditis (VMC). Methods Such databases as PubMed (1950 to 2009), EMbase (1974 to 2009), and The Cochrane Library (December 2009) were searched to include clinical research reports of diagnosing viral myocarditis with MRI. QUADAS items were used to evaluate the quality of the included studies. The Meta-disc software was used to conduct merger analyses on sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio. The Heterogeneity test was performed and summary receiver operating characteristic curve (SROC) was completed. Results Five trials were included. The value of merger sensitivity, specificity, and diagnostic odds ratio (DOR) were 0.94, 0.69, 2.76, and 28.11, respectively. The area under of SROC curve (AUC) was 0.871 9. Conclusion The current evidence shows that cardiac MRI has high sensitivity (94%) and moderate specificity (69%) in the diagnosis of viral myocarditis. The positive rate in the viral myocarditis group is 28.11 times as high as that in the non-viral myocarditis group, so Cardiac MRI has good diagnostic values for viral myocarditis.
【摘要】 目的 探讨原发性中枢神经系统淋巴瘤(PCNSL)的CT及MRI表现特征,以提高术前对该病的影像诊断能力。方法 分析2008年1月—2009年8月华西医院16例经病理证实PCNSL患者的CT、MRI资料及病理资料。结果 病理检查均为B细胞来源的弥漫性大B细胞性淋巴瘤。16例PCNSL 29个病灶,单发11例(69%)，多发5例(31%)18个病灶。病灶好发部位依次是大脑半球临近蛛网膜下腔12个(41.4%)、脑室周围深部白质7个(24.1%)、胼胝体3个(10.3%)。有5例病变CT平扫表现为等或略高于脑实质密度影,无出血和钙化；MRI平扫75.9%(19/25)的病灶T1WI呈等低信号,T2WI等稍低信号,类似“脑膜瘤”样信号,均未见血管流空；增强后病灶大都均匀实质团块状或结节状强化,典型的可出现“尖角征”、“握拳征”,3例可见小囊变,呈“硬环征”。结论 CT对PCNSL的定性诊断作用有限,MRI具有一定特征性表现者,多可作出正确的诊断,但确诊有赖于病理。