Xiao-ming Zhang

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.

CT and MR imaging patterns for pancreatic carcinoma invading the extrapancreatic neural plexus (Part II): Imaging of pancreatic carcinoma nerve invasion

Computed tomography (CT) and magnetic resonance imaging (MRI) are excellent modalities which have the ability to detect, depict and stage the nerve invasion associated with pancreatic carcinoma. The aim of this article is to review the CT and MR patterns of pancreatic carcinoma invading the extrapancreatic neural plexus and thus provide useful information which could help the choice of treatment methods. Pancreatic carcinoma is a common malignant neoplasm with a high mortality rate. There are many factors influencing the prognosis and treatment options for those patients suffering from pancreatic carcinoma, such as lymphatic metastasis, adjacent organs or tissue invasion, etc. Among these factors, extrapancreatic neural plexus invasion is recognized as an important factor when considering the management of the patients.

Anatomic pathways of peripancreatic fluid draining to mediastinum in recurrent acute pancreatitis: visible human project and CT study.

Background In past reports, researchers have seldom attached importance to achievements in transforming digital anatomy to radiological diagnosis. However, investigators have been able to illustrate communication relationships in the retroperitoneal space by drawing potential routes in computerized tomography (CT) images or a virtual anatomical atlas. We established a new imaging anatomy research method for comparisons of the communication relationships of the retroperitoneal space in combination with the Visible Human Project and CT images. Specifically, the anatomic pathways of peripancreatic fluid extension to the mediastinum that may potentially transform into fistulas were studied. Methods We explored potential pathways to the mediastinum based on American and Chinese Visible Human Project datasets. These drainage pathways to the mediastinum were confirmed or corrected in CT images of 51 patients with recurrent acute pancreatitis in 2011. We also investigated whether additional routes to the mediastinum were displayed in CT images that were not in Visible Human Project images. Principal Findings All hypothesized routes to the mediastinum displayed in Visible Human Project images, except for routes from the retromesenteric plane to the bilateral retrorenal plane across the bilateral fascial trifurcation and further to the retrocrural space via the aortic hiatus, were confirmed in CT images. In addition, route 13 via the narrow space between the left costal and crural diaphragm into the retrocrural space was demonstrated for the first time in CT images. Conclusion This type of exploration model related to imaging anatomy may be used to support research on the communication relationships of abdominal spaces, mediastinal spaces, cervical fascial spaces and other areas of the body.

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.

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.

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.

MRI Findings of Otic and Sinus Barotrauma in Patients with Carbon Monoxide Poisoning during Hyperbaric Oxygen Therapy

Background and Purpose To study the MRI findings of otic and sinus barotrauma in patients with carbon monoxide(CO) poisoning during hyperbaric oxygen (HBO) therapy and examine the discrepancies of otic and sinus abnormalities on MRI between barotrauma and acute otitis media with effusion. Materials and Methods Eighty patients with CO-poisoning diagnosed with otic and sinus barotrauma after HBO therapy were recruited. Brain MRI was performed to predict delayed encephalopathy. Over the same period, 88 patients with acute otitis media with effusion on MRI served as control. The abnormalities of the middle ear and paranasal sinuses on MRI were noted and were compared between groups. Nine patients with barotrauma were followed up by MRI. Results In the barotrauma group, 92.5% of patients had bilateral middle ear abnormalities on MRI, and 60% of patients had both middle ear cavity and mastoid cavity abnormalities on MRI in both ears. Both rates were higher than those in the control group (p = 0.000). In the two groups, most abnormalities on MRI were observed in the mastoid cavity. The rate of sinus abnormalities of barotrauma was 66.3%, which was higher than the 50% in the control group (p = 0.033). In the nine patients with barotrauma followed up by MRI, the otic barotrauma and sinus abnormalities had worsened in 2 patients and 5 patients, respectively. Conclusion MRI is able to depict the abnormalities of otic and sinus barotrauma in patients with CO-poisoning during HBO therapy and to differentiate these from acute otitis media with effusion.

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.