Tian-wu Chen

Tumor Volume of Resectable Adenocarcinoma of the Esophagogastric Junction at Multidetector CT: Association with Regional Lymph Node Metastasis and N Stage

PURPOSE To determine whether the volume of resectable adenocarcinoma of the esophagogastric junction (AEG) measured at multidetector computed tomography (CT) is associated with regional lymph node metastasis and N stage. MATERIALS AND METHODS The study was approved by the institutional ethics committee, and written informed consent was obtained from each participant. Two hundred sixteen patients with resectable AEG prospectively underwent contrast material-enhanced thoracoabdominal multidetector CT less than 2 weeks before curative resection. Gross tumor volume was retrospectively measured on CT scans. Univariate and multivariate analyses were performed to identify whether gross tumor volume is associated with regional lymph node metastasis. The Mann-Whitney U test was performed to compare gross tumor volume among N stages, with Bonferroni correction for multigroup comparisons. Receiver operating characteristic analysis was performed to determine if gross tumor volume could help classify N stage. RESULTS Univariate analysis showed that gross tumor volume is associated with regional lymph node metastasis (P < .0001). Multivariate analysis revealed that gross tumor volume is an independent risk factor of lymph node metastasis (P = .023, odds ratio = 2.791). The Mann-Whitney U test showed that gross tumor volume could help differentiate between stage N0 and stages N1-N2 or N1-N3 disease and between stages N1-N2 and stage N3 disease (P < .0001 for all). In patients with stage T1-T3 AEG, gross tumor volume could help differentiate between stage N0 and stages N1-N2 (cutoff, 15.23 cm(3)) or N1-N3 (cutoff, 17.16 cm(3)) disease and between stages N1-N2 and stage N3 disease (cutoff, 33.96 cm(3)). In patients with stage T3 AEG, gross tumor volume could help differentiate stage N0 from stages N1-N2 (cutoff, 18.41 cm(3)) or N1-N3 (cutoff, 19.30 cm(3)) disease and stages N1-N2 from stage N3 disease (cutoff, 33.96 cm(3)). CONCLUSION Gross tumor volume of AEG measured with multidetector CT is associated with regional lymph node metastasis and N stage.

Spleen size measured on enhanced MRI for quantitatively staging liver fibrosis in minipigs.

To investigate whether and how spleen size measured on magnetic resonance imaging (MRI) could be used to stage liver fibrosis.

Preliminary Study of MR Diffusion Tensor Imaging of the Liver for the Diagnosis of Hepatocellular Carcinoma

Objectives To evaluate the feasibility of differentiating between hepatocellular carcinomas (HCC) and healthy liver using diffusion tensor imaging (DTI). Material and Methods All subjects underwent an abdominal examination on a 3.0T MRI scanner. Two radiologists independently scored the image quality (IQ). An optimal set of DTI parameters was obtained from a group of fifteen volunteers with multiple b-values (100, 300, 500, and 800 s/mm2) and various diffusion-encoding directions (NED = 6, 9, and 12)using two way ANOVA analysis. Eighteen Patients with HCC underwent DTI scans with the optimized parameters. Fractional anisotropy(FA) and average apparent diffusion coefficient (ADC) values were measured. The differences of FA and ADC values between liver healthy region and HCC lesion were compared through paired t tests. Results There were no significant changes in liver IQ and FA/ADC values with increased NED(P >0.05), whereas the liver IQ and FA/ADC values decreased significantly with increased b-values(P <0.05). Good IQ, acceptable scan time and reasonable FA/ADC values were acquired using NED = 9 with b-value of (0,300) s/mm2. Using the optimized DTI sequence, ADC value of the tumor lesion was significantly lower than that of the healthy liver region (1.30 ± 0.34×10−3 vs 1.52 ± 0.27×10−3 mm2/s, P = 0.013), whereas the mean FA value of the tumor lesion (0.42 ± 0.11) was significantly higher than the normal liver region (0.32 ± 0.10) (P = 0.004). Conclusion Either FA or ADC value from DTI can be used to differentiate HCC from healthy liver. HCC lead to higher FA value and lower ADC value on DTI than healthy liver.

Quantitative Assessment of the Presence and Severity of Cirrhosis in Patients with Hepatitis B Using Right Liver Lobe Volume and Spleen Size Measured at Magnetic Resonance Imaging

Objective To determine whether right liver lobe volume (RV) and spleen size measured utilizing magnetic resonance (MR) imaging could identify the presence and severity of cirrhosis in patients with hepatitis B. Methods Two hundred and five consecutive patients with clinically confirmed diagnosis of cirrhosis due to hepatitis B and 40 healthy control individuals were enrolled in this study and underwent abdominal triphasic enhanced scans using MR imaging. Spleen maximal width (W), thickness (T) and length (L), together with RV and spleen volume (SV), were measured utilizing MR imaging. Spleen multidimensional index (SI) was obtained by multiplying previously acquired parameters W×T×L. Then statistical assessment was performed to evaluate the ability of these parameters, including RV, SV, RV/SV and SI, to identify the presence of cirrhosis and define Child-Pugh class of this disease. Results SV and SI tended to increase (r = 0.557 and 0.622, respectively; all P<0.001), and RV and RV/SV tended to decrease (r = −0.749 and −0.699, respectively; all P<0.001) with increasing Child-Pugh class of cirrhosis. All the parameters, including RV, SV, RV/SV and SI, might be the indicators used to discriminate the patients with liver cirrhosis from the control group, and to distinguish these patients between Child-Pugh class A and B, between B and C, and between A and C (area under receiver operating characteristic curve [AUC] = 0.609–0.975, all P<0.05). Among these parameters, RV/SV was the best noninvasive factor for the discrimination of liver cirrhosis between Child-Pugh class A and B (AUC = 0.725), between A and C (AUC = 0.975), and between B and C (AUC = 0.876), while SI was the best variable to distinguish the cirrhosis patients from the control group (AUC = 0.960, P<0.05). Conclusion RV/SV should be used to identify the severity of cirrhosis, while SI can be recommended to determine the presence of this disease.

The diameter of the originating vein determines esophageal and gastric fundic varices in portal hypertension secondary to posthepatitic cirrhosis

OBJECTIVE: The aim of this study was to determine whether and how the diameter of the vein that gives rise to the inflowing vein of the esophageal and gastric fundic varices secondary to posthepatitic cirrhosis, as measured with multidetector-row computed tomography, could predict the varices and their patterns. METHODS: A total of 106 patients with posthepatitic cirrhosis underwent multidetector-row computed tomography. Patients with and without esophageal and gastric fundic varices were enrolled in Group 1 and Group 2, respectively. Group 1 was composed of Subgroup A, consisting of patients with varices, and Subgroup B consisted of patients with varices in combination with portal vein-inferior vena cava shunts. The diameters of the originating veins of veins entering the varices were reviewed and statistically analyzed. RESULTS: The originating veins were the portal vein in 8% (6/75) of patients, the splenic vein in 65.3% (49/75) of patients, and both the portal and splenic veins in 26.7% (20/75) of patients. The splenic vein diameter in Group 1 was larger than that in Group 2, whereas no differences in portal vein diameters were found between groups. In Group 1, the splenic vein diameter in Subgroup A was larger than that in Subgroup B. A cut-off splenic vein diameter of 8.5 mm achieved a sensitivity of 83.3% and specificity of 58.1% for predicting the varices. For discrimination of the varices in combination with and without portal vein-inferior vena cava shunts, a cut-off diameter of 9.5 mm achieved a sensitivity of 66.7% and specificity of 60.0%. CONCLUSION: The diameter of the splenic vein can be used to predict esophageal and gastric fundic varices and their patterns.

Preliminary Study of MR Diffusion Tensor Imaging of Pancreas for the Diagnosis of Acute Pancreatitis

Objectives To evaluate the feasibility of differentiating between acute pancreatitis (AP) and healthy pancreas using diffusion tensor imaging (DTI) and correlate apparent diffusion coefficient (ADC) /fractional anisotropy (FA) values with the severity of AP. Material and Methods 66 patients diagnosed with AP and 20 normal controls (NC) underwent DTI sequences and routine pancreatic MR sequences on a 3.0T MRI scanner. Average ADC and FA values of the pancreatic were measured. Differences of FA and ADC values between the AP group and the NC group with AP and healthy pancreas were compared by two-sample independent t-test. The severity of AP on MRI was classified into subgroups using MR severity index (MRSI), where the mean FA and ADC values were calculated. Relationship among the FA values, ADC values and MRSI were analyzed using Spearmans rank correlation coefficients. Results The pancreatic mean ADC value in the AP group (1.68 ± 0.45×10−3mm2/s) was significantly lower than in the NC group (2.09 ± 0.55×10−3mm2/s) (P = 0.02); the same as mean FA value (0.39 ± 0.23 vs 0.54 ± 0.12, P = 0.00). In the subgroup analysis, the pancreatic ADC and FA value of edema AP patients was significantly higher than necrosis AP patients with P = 0.000 and P = 0.001respectively. In addition, as severity of pancreatitis increased according to MRSI, lower pancreatic ADC (r = -0.635) and FA value (r = -0.654) were noted. Conclusion Both FA and ADC value from DTI can be used to differentiate AP patients from NC. Both ADC and FA value of pancreas have a negative correlation with the severity of AP.

Common bile duct diameter in an asymptomatic population: A magnetic resonance imaging study

AIM To measure the common bile duct (CBD) diameter by magnetic resonance cholangiopancreatography (MRCP) in a large asymptomatic population and analyze its some affecting factors. METHODS This study included 862 asymptomatic subjects who underwent MRCP. The CBD diameter was measured at its widest visible portion on regular end-expiration MRCP for all subjects. Among these 862 subjects, 221 volunteers also underwent end-inspiration MRCP to study the effect of respiration on the CBD diameter. The age, sex, respiration, body length, body weight, body mass index (BMI), portal vein diameter (PVD), length of the extrahepatic duct and CBD, cystic junction radial orientation and location were recorded. The subjects were divided into 7 groups according to age. All of the above factors were compared with the CBD diameter on end-expiration MRCP. RESULTS Among the 862 subjects, the CBD diameter was 4.13 ± 1.11 mm (range, 1.76-9.45 mm) and was correlated with age (r = 0.484; P < 0.05), with a dilation of 0.033 mm per year. The upper limit of the 95% reference range was 5.95 mm, resulting in a reasonable upper limit of 6 mm for the asymptomatic population. Respiration and other factors, including sex, body length, body weight, BMI, PVD, length of the extrahepatic duct and CBD, cystic junction radial orientation and location, were not related to the CBD diameter. CONCLUSION We established a reference range for the CBD diameter on MRCP for an asymptomatic population. The CBD diameter is correlated with age. Respiration did not affect the non-dilated CBD diameter.

Liver Lobe Volumes and the Ratios of Liver Lobe Volumes to Spleen Volume on Magnetic Resonance Imaging for Staging Liver Fibrosis in a Minipig Model

Objective To investigate liver lobe volumes and the ratios of liver lobe volumes to spleen volume measured with magnetic resonance imaging (MRI) for quantitatively monitoring and staging liver fibrosis. Methods Animal study was approved by Institutional Animal Care and Use Committee. Sixteen minipigs were prospectively used to model liver fibrosis, and underwent abdominal gadolinium-enhanced MRI on 0, 5th, 9th, 16th and 21st weekend after modeling this disease staged by biopsy according to METAVIR classification system. On MRI, volume parameters including left lateral liver lobe volume (LLV), left medial liver lobe volume (LMV), right liver lobe volume (RV), caudate lobe volume (CV), and spleen volume (SV) were measured; and LLV/SV, LMV/SV, RV/SV and CV/SV were calculated. Statistical analyses were performed for staging this fibrosis. Results LLV and CV increased with increasing stage of fibrosis (r = 0.711, 0.526, respectively; all P < 0.05). RV and LMV increased from stage 0 to 2 and decreased from 2 to 4; and RV/SV decreased from 0 to 1, increased from 1 to 2, and decreased from 3 to 4 (all P > 0.05). LLV/SV, LMV/SV and CV/SV decreased from stage 0 to 4 (r = -0.566, -0.748 and -0.620, respectively; all P < 0.05). LLV, CV, LLV/SV, LMV/SV, RV/SV, and CV/SV could distinguish stage 0–1 from 2–4 and 0–2 from 3–4 (all P < 0.05). Among these parameters, LLV and LMV/SV could best classify stage ≥2 and ≥3, respectively (area under receiver operating characteristic curve = 0.893 and 0.946, respectively). Conclusion LLV and LMV/SV complement each other in staging liver fibrosis, and both parameters should be used to stage this disease.

Magnetic resonance-based total liver volume and magnetic resonance-diffusion weighted imaging for staging liver fibrosis in mini-pigs

AIM To determine whether and how magnetic resonance imaging (MRI)-based total liver volume (TLV) and diffusion weighted imaging (DWI) could predict liver fibrosis. METHODS Sixteen experimental mature mini-pigs (6 males, 10 females), weighing between 20.0 and 24.0 kg were prospectively used to model liver fibrosis induced by intraperitoneal injection of 40% CCl(4) dissolved in fat emulsion twice a week for 16 wk, and by feeding 40% CCl(4) mixed with maize flour twice daily for the subsequent 5 wk. All the survival animals underwent percutaneous liver biopsy and DWI using b = 300, 500 and 800 s/mm(2) followed by abdominal gadolinium-enhanced MRI at the 0, 5th, 9th, 16th and 21st weekend after beginning of the modeling. TLV was obtained on enhanced MRI, and apparent diffusion coefficient (ADC) was obtained on DWI. Hepatic tissue specimens were stained with hematoxylin and Massons trichrome staining for staging liver fibrosis. Pathological specimens were scored using the human METAVIR classification system. Statistical analyses were performed to determine whether and how the TLV and ADC could be used to predict the stage of liver fibrosis. RESULTS TLV increased from stage 0 to 2 and decreased from stage 3 (r = 0.211; P < 0.001). There was a difference in TLV between stage 0-1 and 2-4 (P = 0.03) whereas no difference between stage 0-2 and 3-4 (P = 0.71). TLV could predict stage ≥ 2 [area under receiver operating characteristic curve (AUC) = 0.682]. There was a decrease in ADC values with increasing stage of fibrosis for b = 300, 500 and 800 s/mm(2) (r = -0.418, -0.535 and -0.622, respectively; all P < 0.001). Differences were found between stage 0-1 and 2-4 in ADC values for b = 300, 500 and 800 s/mm(2), and between stage 0-2 and 3-4 for b = 500 or 800 s/mm(2) (all P < 0.05). For predicting stage ≥ 2 and ≥ 3, AUC was 0.803 and 0.847 for b = 500 s/mm(2), and 0.848 and 0.887 for b = 800 s/mm(2), respectively. CONCLUSION ADC for b = 500 or 800 s/mm(2) could be better than TLV and ADC for b = 300 s/mm(2) to predict fibrosis stage ≥ 2 or ≥ 3.

Patterns of Lymph Node Recurrence after Radical Surgery Impacting on Survival of Patients with pT1-3N0M0 Thoracic Esophageal Squamous Cell Carcinoma

The aim of this study was to investigate how patterns of lymph nodes recurrence after radical surgery impact on survival of patients with pT1-3N0M0 thoracic esophageal squamous cell carcinoma. One hundred eighty consecutive patients with thoracic esophageal squamous cell carcinoma underwent radical surgery, and the tumors were staged as pT1-3N0M0 by postoperative pathology. Lymph nodes recurrence was detected with computed tomography 3-120 months after the treatment. The patterns of lymph nodes recurrence including stations, fields and locations of recurrent lymph nodes, and impacts on patterns of survival were statistically analyzed. There was a decreasing trend of overall survival with increasing stations or fields of postoperative lymph nodes involved (all P<0.05). Univariate analysis showed that stations or fields of lymph nodes recurrence, and abdominal or cervical lymph nodes involved were prognostic factors for survival (all P<0.05). Cox analyses revealed that the field was an independent factor (P<0.05, odds ratio=2.73). Lymph nodes involved occurred predominantly in cervix and upper mediastinum (P<0.05). In conclusion, patterns of lymph node recurrence especially the fields of lymph nodes involved are significant prognostic factors for survival of patients with pT1-3N0M0 thoracic esophageal squamous cell carcinoma.