Objective To evaluate the value of differential diagnosis between benign and malignant thyroid lesions by susceptibility weighted imaging(SWI).Methods 53 patients with 20 malignant thyroid lesions and 71 benign thyroid lesions confirmed by surgery and pathology were analyzed retrospectively.All cases received conventional MRI and SWI preoperatively.Location,volume,SWI parameters including signal to noise ratio(SNR),contrast noise ratio(CNR)and intratumor susceptibility hypointensity (ITSHIA)datas in benign and malignant lesions were compared and analyzed.Results There was no statistical significance between benign and malignant thyroid lesions in the location,volume,SNR and CNR(χ2 or t =0.014,0.286,0.927,1.169;P =0.907,0.778,0.368,0.259 respectively).The maximum diameter (1.90 mm±0.32 mm),degree of maximum diameter(1.33±0.47),frequence(1.40±0.20)and area ratio(1.09±0.28)for benign thyroid lesions were less than those for malignant lesions(3.39 mm±0.79 mm,2.25±0.44,1.40±0.68,1.70±0.47)respectively (t or Z =12.629,5.788,3.41 5,5.795;P =0.000,0.000,0.001,0.000).Conclusion SWI semiquantitative assessment of pathlogical vascularity is useful in differential diagnosis of benign and malignant thyroid lesions.

PurposeTo evaluate the significance of ultrasonic elastography strain ratio, MRI and the combination of both in diagnosis of breast tumor.Materials and MethodsFifty-four cases with single breast tumor underwent preoperative ultrasound elasticity imaging and MRI. Accuracy of ultrasound elastography strain rate ratio (SRR) of the tumor and surrounding normal breast tissue was measured by quantitative ultrasound elastography, and its combination with MRI were analyzed. ResultsThere was signiifcant differences on SRR between the benign group and the malignant group (2.24±1.28vs 4.96±1.73, t=2.648,P<0.05). Optimal threshold of ultrasonic elastography SRR in differential diagnosis of breast benign from malignant tumor was 2.41 determined by ROC curve. The accuracy of SRR, MRI and the combination of both in differentiating benign from malignant breast tumor was 81.48% (44/54), 85.19% (46/54) and 96.30%(52/54), respectively. There was no statistic difference between SRR and MRI in diagnostic accuracy (χ2=0.267,P>0.05). Combined both had higher diagnosis accuracy when compared with SR and MRI separately (χ2=6.000 and 3.967,P<0.05).Conclusion Ultrasonic elastography strain ratio is accurate and objective in differentiating benign from malignant breast tumors. It is a valuable quantitative index in clinical practice. Moreover, SRR combined with MRI can reduce the misdiagnosis rate.

Objective To investigate the association of MRI features with HER-2 expression in non-mass-like breast carcinoma. Methods 74 patients with breast cancers diagnosed by pathology underwent MRI prior to surgery,and all lesions were non-mass-like enhancement on dynamic contrast-enhanced MRI.The expression of HER-2 in tumor tissue was detected by immunohistochemical staining.Chi-square test,Fisher’s exact test and spearman rank correlation were used to evaluate the correlations between the morphological characteristics, dynamic enhanced MR parameters,ADC value and HER-2 expression.Results The tumor size was correlated positively with the expression degree of HER-2 (r=0.341,P =0.003).The ADC value was also correlated positively with the positive expression degree of HER-2 (r=0.31 7,P =0.006).However,the time to peak was correlated negatively with that (r =-0.244,P =0.036).No significant correlations between the distribution/internal enhancement manner,the type of time signal intensity curve and HER-2 expression were found (all P >0.05).Conclusion Tumor size,time to peak and ADC value are correlated with the expression of HER-2 in non-mass-like breast carcinoma,which is helpful for the treatment plan and prognosis evaluation for this cancer.

Objective To determine the utility of single energy CT value and spectrum energy curve in identifying different cause of diffuse spleen enlargement.Methods 43 patients confirmed by either surgical pathology,aspiration biopsy or clinical comprehensive diagnosis and follow-up were assessed,including lymphoma with spleen infiltration(lymphoma group,n=18) and cirrhotic splenomegaly(liver cirrhosis group,n=25).All patients underwent upper abdomen CT scans in GSI mode and the GSI data were transferred to the Workstation AW 4.6 to acquire single energy CT value(40-140 keV,10 keV's interval) and spectrum energy curve of the spleen on the venous phase.All single energy CT values and the slope of curves were comparatively analyzed through independent-samples t test.The diagnostic efficiency were evaluated by ROC analysis.Results Under 40-140 keV energy range,single energy CT values were significantly lower in the lymphoma group than in the liver cirrhosis group(all P＜0.05).The spectrum energy curve were both types of decreasing.Under 40-90 keV,100-140 keV energy range,the slop of curves in the lymphoma group(2.42 ± 0.70,0.27± 0.08) were also significantly lower than in the liver cirrhosis group (3.11 ± 0.62,0.34± 0.07),respectively(all P ＜0.05).When the slope of curve under 40-90 keV energy range was selected as a diagnostic indicator,the area under the curve(AUC) would reach 0.77.If threshold value of 1.39 was taken,the sensitivity and specificity would be equal to 86 ％ and 64 ％,respectively.Conclusion Single energy CT value and spectrum energy curve are helpful for differentiation of lymphoma with spleen infiltration from cirrhotic splenomegaly.

Objective To investigate the characteristics of multimodal MRI of breast cancer with different molecular subtypes and the correlation between each molecular type and MRI findings. Methods Multimodality MRI date of 87 patients with breast cancer confirmed by pathology were retrospectively analyzed. According to the expression of estrogen receptors(ER),progesterone receptors(PR)and human epidermal growth factor receptor-2 (HER-2),the tumors were classified into triple-negative breast cancer,HER-2 overexpression,Luminal A and Lu-minal B subtypes. The MRI features of breast cancers of different molecular subtypes were compared. Results Among the 87 cases of breast cancer,luminal type A accounted for 29.9%(26/87),luminal type B accounted for 36.8%(32/87),HER-2 type accounted for 19.5%(17/87),and triple-negative type accounted for 13.8%(12/87). The average ADC value is 0.97 × 10-3 mm2/s;those whose irregular or edge burr like mass were more often Lu-minal type MRI,triple-negative breast cancer showed the edge smooth,clear boundary,annular enhancement, more easily showed enhanced mode of TIC type Ⅲ. The mean ADC values of type Luminal and HER-2 over-expres-sion were lower than the mean ADC values of the triple-negative type. Conclusion The different molecular sub-types of breast cancer MRI morphologic and hemodynamic characteristics and the value of ADC has certain charac-teristics. The MRI features of breast cancer can be predicted to analyze the molecular typing,providing a reference for clinical treatment.

Objective To investigate the value of molecular probe USPIO-PEG-sLeX in metastasis model of nasopharyngeal carcinoma. Methods According to the pathological results of transplanted tumors of nude mice with nasopharyngeal carcinoma,the tumor-bearing mice were divided into metastatic group and non-metastatic group.T2 ? values of the transplanted tumors at four different time points were measured before and after the injection of USPIO-PEG-sLeX(t0＝plain scan,t1＝scan immediately after enhancement,t2＝1 hour post-enhancement scan,t3＝2 hours post-enhancement scan).ΔT2 ? and enhancing rates at t1 ,t2,t3 were calculated.Results The plain T2 ? values of the metastatic group and the non-metastatic group were 22.25±8.08 and 27.01±9.45,respectively.There was no significant difference between the two groups at t0 (P＞0.05).The T2 ? values at t1,t2 and t3 were 11.57±4.02 and 24.82±7.84,10.09±4.88 and 24.15±8.74,12.46±5.63,23.42±7.12 respectively in the metastatic and non-metastatic groups,differences were statistically significant (P values were 0.005,0.008 and 0.01 9,respectively).ΔT2 ? values at time t1 ,t2 and t3 in nude mice in the metastatic and non-metastatic groups were 10.69±6.23,3.86±2.20,12.1 7±8.67 and 2.87±1.37,9.80±3.03,4.32±2.28 respectively.The differences were statistically significant (P values were 0.027,0.048 and 0.043,respectively).The enhancement rates at t1,t2 and t3 in nude mice in metastatic and non-metastatic groups were 45.98±14.03,7.10±5.18,5 1.1 5±22.70 and 1 1.04±6.01 ,44.05 ±13.92,12.09 ±7.54,respectively,with statistically significant differences (P values were 0.001,0.005 and 0.007,respectively).After two-way repeated-measures analysis of variance,there was a statistically significant difference in T2 ? values between the metastatic and non-metastatic groups (P＝0.02＜0.05).There was a statistically significant difference in T2 ? values at different times (P＝0.001＜0.05).There was an interaction between the metastatic and non-metastatic groups and the scan time (P＝0.043＜0.05).Conclusion USPIO-PEG-sLeX molecular probe can non- invasively monitor E-selectin expression,and has a good application prospect in monitoring the metastasis of nasopharyngeal carcino-ma xenograft models.