Value of magnetic resonance imaging-proton density fat fraction and FibroScan in quantitative evaluation of liver fat content in patients with chronic hepatitis B / 临床肝胆病杂志

Objective To investigate the value of magnetic resonance imaging-proton density fat fraction (MRI-PDFF) and FibroScan in the quantitative evaluation of liver fat content in patients with chronic hepatitis B (CHB). Methods A total of 96 patients with CHB who were hospitalized in Department of Hepatology, The Second Clinical Medical College of Guangzhou University of Chinese Medicine, from February 2017 to July 2020 were enrolled, and all patients were diagnosed based on liver pathological examination. MRI-PDFF and FibroScan were performed before surgery. According to the results of liver biopsy, the patients were divided into non-fatty liver disease group with 44 patients, mild fatty liver disease group with 33 patients, and moderate-to-severe fatty liver disease group with 19 patients. A one-way analysis of variance was used for comparison of normally distributed continuous data between multiple groups, and the least significant difference t -test was used for further comparison between two groups; the Kruskal-Wallis H test was used for comparison of non-normally distributed continuous data between multiple groups, and the Mann-Whitney U test was used for further comparison between two groups; Bonferroni correction was also performed. The receiver operating characteristic (ROC) curve was plotted to analyze the area under the ROC curve (AUC) of hepatic fat fraction (HFF) and controllable attenuation parameters (CAP) in the diagnosis of fatty liver disease and obtain their sensitivities, specificities, and optimal cut-off values. The intraclass correlation coefficient was used to investigate the consistency of MRI-PDFF data. Results The moderate-to-severe fatty liver disease group had a significant increase in MRI-PDFF HFF compared with the non-fatty liver disease group and the mild fatty liver disease group (all P < 0.05), and the mild fatty liver disease group had a significant increase in MRI-PDFF HFF compared with the non-fatty liver disease group( P < 0.05). The moderate-to-severe fatty liver disease group had a significant increase in FibroScan CAP compared with the non-fatty liver disease group and the mild fatty liver disease group (all P < 0.05), and the mild fatty liver disease group had a significant increase in FibroScan CAP compared with the non-fatty liver disease group ( P < 0.05). In the diagnosis of mild fatty liver disease, MRI-PDFF HFF had an AUC of 0.901 ( P < 0.001), a sensitivity of 90.9%, and a specificity of 82.7% at the optimal cut-off value of 5.1%, and in the diagnosis of moderate-to-severe fatty liver disease, MRI-PDFF HFF had an AUC of 0.972 ( P < 0.001), a sensitivity of 96.1%, and a specificity of 89.5% at the optimal cut-off value of 9.7%. In the diagnosis of mild fatty liver disease, FibroScan CAP had an AUC of 0.829 ( P < 0.001), a sensitivity of 77.3%, and a specificity of 78.8% at the optimal cut-off value of 258.5 dB/m, and in the diagnosis of moderate-to-severe fatty liver disease, FibroScan CAP had an AUC of 0.830 ( P < 0.001), a sensitivity of 76.6%, and a specificity of 78.9% at the optimal cut-off value of 285.5 dB/m. Conclusion Both MRI-PDFF and FibroScan can objectively evaluate the degree of fatty liver disease in patients with CHB. MRI-PDFF HFF and FibroScan CAP can be used as noninvasive markers for the quantitative analysis of CHB with hepatic steatosis, and MRI-PDFF HFF tends to have higher diagnostic efficiency.

Value of prostate specific antigen density in clinical decision-making for prostate imaging reporting and data system v2 category 3 lesions / 中国医学影像技术

Objective To explore the value of prostate specific antigen density (PSAD) in clinical decision making for patients with prostate imaging reporting and data system version 2 (PI-RADS v2) category 3 lesions.Methods Totally 54 patients with PI-RADS v2 category 3 lesions who underwent prostate biopsy before MRI were enrolled and divided into prostate cancer (PCa) group (n=11) and benign group (n=43) according to biopsy results.Then clinical data and imaging features,including total prostate specific antigen (TPSA),free prostate specific antigen (FPSA),FPSA/TPSA ratio (F/T),PSAD,prostate volume and the volume of index lesion were collected and statistically analyzed between the two groups.ROC curve was used to evaluate the diagnostic efficacy of PSAD in predicting malignant and benign lesions in patients with PI RADS v2 category 3 lesions.Results PSAD had statistical difference (P=0.006),whereas TPSA,FPSA,F/T,prostate volume and the volume of index lesion showed no statistical differences between PCa group and benign group (all P＞0.05).ROC curves showed that area under the curve was 0.771(P＜0.05).Using the optimal threshold of PSAD-0.25 ng/ml2,the sensitivity and specificity of PSAD in predicting PCa and benign lesions was 72.73 ％ (8/11) and 74.42％(32/43),respectively.Conclusion PSAD is an effective index to predict the risk of PCa in patients with PI-RADS v2 category 3 lesions.Using the threshold of PSAD=0.25 ng/ml2 to screen high risk patients for prostate biopsy,the positive rate could be improved and unnecessary biopsies could be avoided.

MSCT diagnosis of gastrointestinal foreign bodies and perforations / 中国医学影像技术

Objective To observe the value of MSCT in diagnosis of gastrointestinal foreign bodies and the resulting gastrointestinal perforations.Methods MSCT and clinical data of 30 patients with gastrointestinal foreign bodies,including 17 with gastrointestinal perforations were reviewed retrospectively.The location,morphology,density of foreign bodies,and the performances of gastrointestinal perforations were observed.Results All gastrointestinal foreign bodies could be displayed by MSCT in 30 patients.Toothpicks were the most common type of foreign bodies (12/30,40.00％),followed by fish bones (5/30,16.67％),jujube nuclei (3/30,10.00％),chicken bones (2/30,6.67％) and so on.Foreign bodies were found in small intestine in 15 patients (15/30,50.00％),in stomach in 7 (7/30,23.33％),in colon in 6 (6/30,20.00％) and in ileocecus in 2 patients (2/30,6.67％).High density foreign bodies were demonstrated on abdominal X-ray films in 11 patients (11/30,36.7 ％).Gastrointestinal perforations caused by toothpicks,fishbones and other sharp objects were observed in 14 patients (14/17,82.35 ％).Intestinal wall edema,peripheral exudation,foreign bodies "cross through the intestinal wall" and the surrounding small bubbles were found in perforation site or nearby.Conclusion MSCT can comprehensively display the location,shape and associated changes of gastrointestinal foreign bodies,with important diagnostic value for gastrointestinal perforations.

Use of coronary CT angiography in the diagnosis of patients with suspected coronary artery disease: findings and clinical indications / 老年心脏病学杂志（英文版）

Objective To investigate the clinical applications of coronary CT angiography in patients with suspected coronary artery disease and identify factors that affect CT findings. Methods Medical records of patients suspected of coronary artery disease over a period of 12 months from a tertiary teaching hospital were retrospectively reviewed. Patient age, sex (male/female), duration of symptoms and abnormal rates of coronary CT angiography scans were analysed to investigate the relationship among these parameters. The patients by age were duration of symptoms was also classified into five groups: less than one week, one week to one month, one to three months, three to six months and more than six months. Results Of the 880 patient records reviewed, 800 met the above study criteria. Five hundred and forty nine patients demonstrated abnormal CT findings (68.6%). There was no significant difference in the percentage of abnormal CT findings based on patient sex and the duration of symptoms (P = 0.14). The abnormal rates of coronary CT angiography, however, increased significantly with increasing age (P < 0.001); with patients over 65 years of age 2.5 times more likely to have an abnormal CT scan relative to a patient under 45 years. A significant difference was found between abnormal coronary CT angiography and the duration of symptoms (P = 0.012). Conclusions Our results indicate coronary CT angiography findings are significantly related to the patient age group and duration of symptoms. Clinical referral for coronary CT angiography of patients with suspected coronary artery disease needs to be justified with regard to the judicious use of this imaging modality.

Applied Value of Diffusion Tensor Imaging in Early Evaluation of Prognosis of Hypoxic-Ischemic Encephalopathy in New Infants / 实用放射学杂志

Objective To study the value of diffusion tensor imaging(DTI) in early assessment of prognosis of hypoxic-ischemicencephalopathy(HIE) in new infants. Methods 96 cases of full term infants with HIE underwent DTI examinations at 0～12 days and 6～36 months. Based on clinical diagnostic criteria, 96 cases were divided into three groups: mild, moderate and severe HIE groups. Fractional anisotropy(FA) values in the corpus callosum splenium and the posterior limb of internal capsules were measured. Results (1) Varying degrees of FA groups was significantly different from the same site, increased linearly with time,but the magni-tude of change was different;(2)When FA value of corpus callosum splenium in the cut-off point was ≥0.437,the sensitivity(SE) was 83.8% , the specificity(SP) was 18.6% , ROC area under the curve was 0.903 , 95% confidence interval was from 0.846 to 0.961,standard error was 0.029;when FA value of posterior limb of internal capsule in the cut-off point ≥0.391,SE was 86.5%, SP was 11.9% ,ROC area under the curve was 0.940,95% confidence interval was from 0.898 to 0.984,standard error was 0.022. Conclusion MR DTI examination is of significant value in evaluating early the prognosis of HIE in infants.

Experimental study of renal damage assessment after injection of iodine contrast medium: the role of blood oxygen level-dependent functional MRI with a 3.0 T system / 中华放射学杂志

Objective To evaluate blood oxygen level-dependent (BOLD) MRI on assessing renal damage after injection of iodine contrast medium with a 3.0 T system. Methods Routine MRI examination,including T1WI and T2WI, and BOLD MRI were performed in 29 SD rats with a 3.0 T system before the injection of iodine contrast agent and 20 min, 24 h, 48 h, 72 h after the injection, respectively. T2 * and R2 * ( = 1/T2 * ) measurements were obtained in the cortex, inner and outer medulla of kidney,respectively. The results obtained before contrast agent administration were considered as the self-controls.AVONA test were used for the comparison of R2 * values in different parts of both kidneys before contrast agent administration. Two-sample t test was used to compare R2 * values before and at each time point after contrast agent administration, and R2 * values in different parts of the kidneys. Results Before contrast agentadministration, R2 * values in outer medulla in both sides of kidney [R2 *left oM = (31.76 ± 2.73 ) / s,R2 * right OM = (32.77±3.07) /s] were higher than those in cortex [R2 * left c=(30.20±3.48) /s,R2 * right c = (28.84 ±3.11 )/s] and in inner medulla [ R2 * letf IM = (29.54 ± 2.42) /s, R2 * right IM =(28.37±2.80) /s ] ( F = 3.357 and 14.961, P＜ 0.05 ). There was no statistical significance in R2 *values in the three parts between left and right kidney, including cortex, outer and inner medulla (P＞0.05). After contrast agent administration, R2* values in outer medulla changed obviously, which reached to the peak values at 20 minutes after contrast agent administration [R2* left OM = ( 43.57 ± 3.84 )/s,R2*right OM= (44.58±3.13) /s] and dropped from 24 hours [R2*left OM = (42.07 ±4.82) /s,R2* right OM = (42.89±3.40) /s]. R2* values in inner medulla and cortex only presented slight changes.Conclusion R2* values reflected the changes of oxygen content in renal cortex and medulla quantitatively,which helped for detecting medullar ischemia and hypoxia. BOLD MR imaging could offer a feasible method for evaluating oxygen metabolism and renal injury in cortex and medulla.

Analysis of Image Quality of Diffusion Weighted Imaging in Liver Lesions / 实用放射学杂志

Objective To investigate the correlation between b value and image quality of diffusion weighted imaging(DWI).Methods DWI was performed in 20 healthy volunteers and 60 patients with liver lesions.Signal to noise ratio ( SNR ) and contrast to noise ratio ( CNR ) were calculated . Results The mean SNR was larger than 5 when b value was 100 s/mm2 or 300 s/mm2, while b value was 600 s/mm2 or 1100 s/mm2, SNR was less than 5. With b value increased, the influence of blood supply on ADC decreased, but the artifacts increased and CNR decreased, CNR of cystic lesions decrease more than that of solid lesions.Conclusion The gradient factor(b)between 300 s/mm2 and 600 s/mm2 is the most suitable in DWI.

Image Analysis of Benign Obstructive Jaundice on MRCP / 实用放射学杂志

Objective To investigate the qualitative diagnostic value of MRCP in patients with benign obstructive jaundice.Methods MRCP and conventional MR images were performed in 128 patients with benign obstructive jaundice on a superconductive MR scanner (Plilips medical systems Inc. Eclipse. 1.5T) . Final diagnosis was confirmed by surgical and histopathological findings in 123 patients and other 5 patients by follow-up.Results The accuracy of location diagnosis of MRCP was 100%; the qualitative diagnosis was 95.3%. The specificity, accuracy, sensitivity of the deadwood-sign for diagnosis of benign obstructive jaundice were 100%, 95.3%, 85.7% respectively. Conclusion The deadwood-sign was a specific indicator in MRCP of benign obstructive jaundice.