Objective To evaluate the role of apparent diffusion coefficients (ADC) in assesment of response to chemotherapy in patients with gastrointestinal liver metastasis. MethodsTen patients with liver metastasis （8 from colorectal cancer， 1 from gastric cancer， 1 from esophageal cancer） at Peking University People’s Hospital from April 2006 to April 2007 were included. All of them received chemotherapy （FOLFOX6： 4 cases， XELOX： 3 cases, and FOLFIRI： 1 case in 8 cases of colorectal liver metastases; ECF: 1 case of gastric liver metastases; DCF: 1 case of esophageal liver metastasis）. ADC were calculated after MR duffusionweight imaging exmination (GE MEDICAL SYSTEMS HD EXCITE 1.5 T) 1 month pre-and post-chemotherapy, respectively. Tumour response to chemotherapy was assessed by RECIST criteria. ResultsTumors with low pretreatment ADC (lt;9.04×10－4 mm2/s) responded better to chemotherapy than that with high ADC (gt;9.04×10－4 mm2/s); pretreatment ADC of cases (6/10) were remarkable lower than those of cases (4/10)， P＝0.033. Increased ADC after onemonth chemotherapy in patients with liver metastasis predicted a better response. ConclusionsLow pretreatment ADC is predictive of better response to chemotherapy. An increased ADC after treatment predicts a better response to chemotherapy.
ObjectiveTo compare the effectiveness of T2 weighted image (T2WI) and some compounded MRI techniques, including T2WI combined with magnetic resonance spectroscopy (T2WI+MRS), T2WI combined with diffusion weighted imaging (T2WI+DWI) and T2WI combined with dynamic contrast-enhancement [T2WI+(DCE-MRI)] respectively, with 1.5 T MR scanner in diagnosing prostate cancer through a blinding method. MethodsBetween March 2011 and April 2013, two observers diagnosed 59 cases with a blinding method. The research direction of radiologist A was to diagnose prostate cancer. The observers diagnosed and scored the cases with T2WI, T2WI+(DCE-MRI), T2WI+MRS, T2WI+DWI and compositive method respectively. The data were statistically analyzed with receiver operating characteristic (ROC) curve. ResultsAccording to the ROC curve, both observers got the sequence of area under curve (AUC) as T2WI+DWI > T2WI+(DCE-MRI) > T2WI+MRS > T2WI. On the basis of the result from observer A, the AUC from each technique was similar. The AUC of T2+DWI was slightly bigger than others. The specificity of single T2WI was the lowest; the sensitivity of T2WI was slightly higher. The AUC of the compositive method was marginally larger than T2WI+DWI. According to the result from observer B, the AUC of T2WI+DWI was obviously larger than the others. The AUC of single T2WI was much smaller than the other techniques. The single T2WI method had the lowest sensitivity and the highest specificity. The AUC of T2WI+DWI was slightly larger than the compositive method. The AUC of T2WI+(DCE-MRI), T2WI+MRS, single T2WI methods from observer A was obviously higher than those from the score of observer B. The AUC of T2WI+DWI from the two observers was similar. ConclusionThe method of combined T2WI and functional imaging sequences can improve the diagnosing specificity when a 1.5 T MR scanner is used. T2WI+DWI is the best method in diagnosing prostate cancer with least influence from the experience of observers in this research. The compositive method can improve the diagnosis of prostate cancer effectively, but when there are contradictions between different methods, the T2WI+DWI should be considered as a key factor.
ObjectiveTo investigate the significance of apparent diffusion coefficient (ADC value) for pretrea-tment prediction of short-term treatment effect in patients with hepatocellular carcinoma (HCC) who underwent transca-theter arterial chemoembolization (TACE). MethodsA total of twelve HCC patients with twenty-three HCC lesions who underwent TACE in our hospital from May. 2014 to May. 2015 were enrolled prospectively, to explore the difference between pre-and post-TACE in diameter of tumor, ADC value of HCC lesions, ADC value of liver parenchyma, and analyze the predictive significance of ADC value of HCC lesions for TACE in treatment of HCC. ResultsThere were no statistical difference between pre-and post-TACE in diameter of HCC lesions and ADC value of liver parenchyma (P=0.635, P=0.473), but the ADC value of HCC lesions was higher after TACE than pre-TACE (P=0.003). After TACE, the area of necrosis in HCC lesions was≥50% in 17 lesions (73.9%, good effect group), and <50% in 6 lesions (26.1%, poor effect group). Compared with poor effect group, ADC values of HCC lesions in good effect group were both higher before and after TACE (P<0.050). Area under ROC curve (AUC value) of ADC value in HCC lesions before TACE for predicting the effect of TACE was 0.690 (95% CI:0.510-0.879), with the sensitivity and specificity of 82.3% (95% CI:65.5%-93.2%) and 53.8% (95% CI:25.1%-80.8%) respectively, and the demarcation point for good effect and poor effect was 1.24×103 mm2/s. ConclusionThis preliminary study demonstrates that the ADC value of HCC lesions before TACE may be a useful indicator to predict early response of TACE in treatment of HCC.
ObjectiveTo analyze findings of 3.0 T diffusion weighted magnetic resonance (MR) in hepatic alveolar echinococcosis and evaluate potential role of apparent diffusion coefficients (ADC) in hepatic alveolar echinococcosis. MethodsThe clinical data of 26 patients with hepatic alveolar echinococcosis from November 2013 to January 2015 in this hospital were analyzed retrospectively. Hepatic MR scannings with diffusion weighted imaging (DWI) sequences (b-value=0, 600, 1 000, and 1 200 s/mm2) were performed in 26 patients with hepatic alveolar echinococcosis. The data of all the patients were stored to the PACS. The lesion features including type, size, distribution, location, and calcification (on the CT) were assessed by two deputy radiologists. TheADCvalues of marginal area, centre area, surrounding area of liver parenchyma tissue were measured at different b values (0, 600, 1 000, and 1 200 s/mm2) and compared. Results①There were 26 patients with a total of 29 lesions, of which involved multiple liver segments, 21 (72%) lesions located in the right lobe, 4 lesions involved simultaneously the left and right lobes. Twenty-four lesions invaded the hepatic vein or portal vein, 20 lesions invaded the intrahepatic bile duct, 10 lesions invaded the right adrenal gland. Seven patients occurred hilar and retroperitoneal lymph nodes metastases, 5 patients occurred pulmonary metastasis, 3 patients occurred brain metastasis, while 3 patients occurred lung and brain metastases simultaneously. ②There were 20 liquefied necrotic lesions, of which 5 lesions marginal area had multiple small round cysts in T2WI, 15 were only solid and without small cyst; The DWI of the centre area in 12 lesions showed a high signal, 8 lesions showed a low signal. There were 9 solid lesions, of which 2 lesions marginal area had multiple small round cysts in T2WI, 7 lesions marginal area were only solid and without cyst in T2WI. The DWI of the solid lesions showed a low signal, there was a "ring" high signal in the edge of lesions. ③At the same b value, theADCvalue of the centre area in the liquefied necrosis lesions were significantly higher than that in the solid lesions (P<0.01). At different b values, theADCvalue of the surrounding liver parenchyma tissue was significantly lower than that of the marginal area (P<0.01) and the centre area (P<0.01) in the liquefied necrosis lesions; theADCvalue of the centre area was significantly higher than that of the marginal area or surrounding liver parenchyma tissue (P<0.05, P<0.01) in the solid lesions. ConclusionsDWI could clearly distinguish structure and composition of hepatic alveolar echinococcosis and has a higher value in distinguishing from other liver dieases. The averageADCvalue of centre area in liquefied necrotic lesions is higher than that in solid lesions.
Objective To explore the differential diagnosis significance of 3.0T MRI united-sequences examination in the diagnosis of benign and malignant breast lesions. Methods A total of 67 breast lesions of 59 patients were collected prospectively, which be treated at the Sichuan Provincial People’s Hospital during July 2015 to January 2017. All patients were underwent bilateral breast 3.0T magnetic resonance plain scan, diffusion weighted imaging, and dynamic enhanced scan successively before surgical operation. Analysis of morphological features of the benign and malignant breast lesions, the time-signal intensity curve (TIC), the apparent diffusion coefficient (ADC), and the combination diagnosis of them were performed. Results Of all 59 patients, 67 lesions were confirmed by histopathology, including 18 benign lesions and 49 malignant lesions. The morphological features (including margin, shape, border, and evenness), the types of TIC of dynamic enhancement, and ADC value between the benign lesions and malignant lesions were statistically significant (P<0.05). The sensitivity and specificity of Fischer scoring system was 89.8% (44/49) and 61.1% (11/18) respectively. The sensitivity and specificity of TIC types was 83.7% (41/49) and 77.8% (14/18) respectively. The diagnostic threshold of ADC value was 1.012×10–3 mm2/s, with the sensitivity and specificity for the diagnosis was 91.8% (45/49) and 83.3% (15/18) respectively. The sensitivity and specificity of the combination of Fischer scoring system and TIC type for diagnosis between benign and malignant breast lesions was 95.9% (47/49) and 72.2% (13/18) respectively. The sensitivity and specificity of the combination of Fischer scoring system, TIC type, and ADC value for benign and malignant breast lesions was 98.0% (48/49) and 83.3% (15/18) respectively. Conclusion The combination of Fischer scoring system, TIC type, and diffusion-weighted imaging for the differential diagnosis between benign lesions and malignant lesions was more effective than single imaging method.
Supported lipid bilayers (SLBs) have been widely used in biomedical and bioengineering research in vitro because its structure and function are similar to natural cell membrane. A fluorescence recovery after photobleaching (FRAP) technique was used to measure the lateral diffusion of the SLBs composed of 1, 2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and 1, 2-dioleoyl-sn-glycero-3-［(N-(5-amino-1-carboxyp-entyl) iminodiacetic acid)］ (DGS-NTA) on the glass slide, and the effects of the DOPC-to-DGS-NTA ratio, small unilamellar vesicles (SUV) producing method, sizes of bleaching areas and concentrations of loading proteins on the SLBs fluidity and diffusion coefficient were studied systematically in this paper. The results demonstrated that: (1) SUV made by probe sonication exhibited more uniform and smaller size compared with that made by film extrusion, but the whole process of SLBs formation must not be exposed to air. (2) The fluorescence recovery rate and diffusion coefficient of the SLBs decreased with the increasing bleaching area size. With the mole ratio of DOPC to DGS-NTA decreasing from 98∶2 to 84∶16, the fluidity and fluorescence recovery degree decreased gradually, and the SLBs would lose its fluidity if the ratio reached to 82∶18. (3) The average fluorescence intensity of SLBs increased linearly with the loading protein concentration (10–40 nmol·L–1), and the protein showed good mobility on the SLBs. The study would provide a good platform of bio-membrane for further research on interactions among cell membrane molecules and subsequent signals response.
ObjectiveTo compare the value of apparent diffusion coefficients (ADCs) of MR-DWI at different b values in evaluating the progression of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE).MethodsAll of 168 patients with HCC who met the inclusion and exclusion criteria and received the TACE for the first time in the Characteristic Medical Center of PAPF were collected retrospectively, who were divided into a stable group and progressive group according to the results of MRI evaluation at the 6th month after the TACE treatment. The clinical and imaging data of the two groups were compared before the TACE treatment. The Cox proportional hazard regression model was used to analyze the risk factors for the disease progression after the TACE treatment. The receiver operating characteristic curve (ROC) was used to analyze the predicting of efficacy evaluation of TACE by the ADC values at different b values.ResultsCompared with the stable group, the proportions of hepatitis B cirrhosis history, portal vein tumor thrombus, and arteriovenous fistula were higher (P<0.05), and the BCLC stage and Child Pugh grade were worse (P<0.05), and the ADC values were higher (P<0.05) in the progressive group. The results of Cox analysis showed that the ADC values at b=600 and 800 s/mm2 before the TACE, history of hepatitis B cirrhosis, portal vein tumor thrombus, arteriovenous fistula, advanced BCLC stage and Child-Pugh grade were the risk factors for the progression at the 6th month after the TACE treatment. When the b value was 800 s/mm2, the ADC value had the highest efficacy in predicting the outcome of patients (area under ROC curve was 0.746), and the best diagnostic cut-off point was 1.20×10–3 mm2/s, the sensitivity was 73.3% and the specificity was 71.8%.ConclusionADC value of MR-DWI could predict progression after TACE in patients with HCC, and ADC value of 800 s/mm2 has a better predictive value for them.