Search

PURPOSE: To determine the accuracy of magnetic resonance imaging-proton density fat fraction (MRI-PDFF) measurements for detecting liver fat content in potential living liver donors and to compare these results using liver biopsy findings. METHODS: A total of 139 living liver donors (men/women: 83/56) who underwent MRI between January 2017 and September 2021 were included in this analysis retrospectively. The PDFFs were measured using both MR spectroscopy (MRS) and chemical shift-based MRI (CS-MRI) for each donor in a blinded manner. RESULTS: Significant positive correlations were found between liver biopsy and MRS-PDFF and CS-MRI PDFF in terms of hepatic steatosis detection [r = 0.701, 95% confidence interval (CI): 0.604–0.798, r = 0.654, 95% CI: 0.544–0.765, P < 0.001, respectively). A weak level correlation was observed between liver biopsy, MRI methods, and vibration-controlled transient elastography attenuation parameters in 42 available donors. Based on receiver operating characteristic (ROC) analysis, MRS-PDFF and CS-MRI PDFF significantly distinguished >5% of histopathologically detected hepatic steatosis with an area under the ROC curve (AUC) of 0.837 ± 0.036 (P < 0.001, 95% CI: 0.766–0.907) and 0.810 ± 0.036 (P < 0.001, 95% CI: 0.739–0.881), respectively. The negative predictive values (NPVs) of MRS-PDFF and CS-MRI PDFF were 88.3% and 81.3%, respectively. In terms of distinguishing between clinically significant hepatic steatosis (≥10% on histopathology), the AUC of MRS-PDFF and CS-MRI were 0.871 ± 0.034 (P < 0.001 95% CI: 0.804–0.937) and 0.855 ± 0.036 (P < 0.001, 95% CI: 0.784–0.925), respectively. The NPVs of MRS-PDFF and CS-MRI were 99% and 92%, respectively. CONCLUSION: The methods of MRS-PDFF and CS-MRI PDFF provide a non-invasive and accurate approach for assessing hepatic steatosis in potential living liver donor candidates. These MRI PDFF techniques present a promising clinical advantage in the preoperative evaluation of living liver donors by eliminating the requirement for invasive procedures like liver biopsy.

PURPOSEIn Budd–Chiari syndrome (BCS), unevenly distributed parenchymal changes and perfusion abnormalities occur due to hepatic venous outflow obstruction. This study aimed to evaluate the changes in the liver parenchyma in BCS using the quantitative magnetic resonance (MR) techniques of MR elastography, T1 and T2 mapping, and diffusion imaging and correlate the quantitative MR parameters through biochemical results and prognostic indices.METHODSFourteen patients with BCS (seven men and seven women) were examined retrospectively. Liver stiffness (kPa), T1 relaxation times (ms) were achieved using the modified Look–Locker inversion recovery (MOLLI) 3(2)3(2)5 sequence and B1-corrected variable flip angle methods, T2 relaxation times (ms), and apparent diffusion coefficient (ADC) values (mm2/s) were measured using regions of interest placed in the same region in all quantitative methods. Measurements were repeated at the precontrast and postcontrast hepatobiliary phases. The reduction rate (RR; %) and adjusted postcontrast T1 (%) were calculated. The values obtained from different liver parenchyma areas (whole liver, caudate lobe, pathological T2 hyperintense tissue, and relatively preserved normal-appearing tissue) were compared using the Wilcoxon signed-rank test. Spearman’s correlation coefficient was used to investigate the correlation between quantitative MR parameters and biochemical parameters/ prognostic scores (Child–Pugh score, Clichy score, and Rotterdam index).RESULTSThe parenchymal stiffness and precontrast T1 values of the caudate lobe were significantly lower than those of the remainder of the parenchyma, whereas the adjusted postcontrast T1 percentages (MOLLI) were significantly higher (P ≤ 0.027). The parenchymal stiffness value, T1 and T2 values, percentages of RR (MOLLI), and adjusted postcontrast T1 values for the pathological tissue and relatively normal tissue were significantly different (P < 0.028). No significant difference was found in terms of ADC values between any of the distinct regions of the liver.A strong correlation was detected between the Child–Pugh score, Clichy score, and precontrast T1 values obtained through the MOLLI sequence (r = 0.867, P = 0.012, r = 0.821, P = 0.023, respectively). No correlation was found between the whole liver stiffness values and the laboratory parameters, fibrosis markers, prognostic indices, or MR parameters. A significant correlation was identified between creatinine levels and several T1 parameters and the T2 relaxation time (r ≥ 0.661, P ≤ 0.052).CONCLUSIONTissue stiffness and T1 relaxation values are high in the areas identified as fibrosis compared with those in the relatively preserved parenchyma. The T1 relaxation time can offer quantitative information for assessing segmental functional changes and prognosis in BCS.ion for assessing segmental functional changes and prognosis in BCS.

PURPOSETo evaluate the frequency of abdominal computed tomography (CT) findings in patients with coronavirus disease-2019 (COVID-19) and interrogate the relationship between abdominal CT findings and patient demographic features, clinical findings, and laboratory test results as well as the CT atherosclerosis score in the abdominal aorta.METHODSThis study was designed as a multicenter retrospective study. The abdominal CT findings of 1.181 patients with positive abdominal symptoms from 26 tertiary medical centers with a positive polymerase chain-reaction test for severe acute respiratory syndrome coronavirus 2 were reviewed. The frequency of ischemic and non-ischemic CT findings as well as the association between CT findings, clinical features, and abdominal aortic calcific atherosclerosis score (AA-CAS) were recorded.RESULTSIschemic and non-ischemic abdominal CT findings were detected in 240 (20.3%) and 328 (27.7%) patients, respectively. In 147 patients (12.4%), intra-abdominal malignancy was present. The most frequent ischemic abdominal CT findings were bowel wall thickening (n = 120; 10.2%) and perivascular infiltration (n = 40; 3.4%). As for non-ischemic findings, colitis (n = 91; 7.7%) and small bowel inflammation (n = 73; 6.2%) constituted the most frequent disease processes. The duration of hospital stay was found to be higher in patients with abdominal CT findings than in patients without any positive findings (13.8 ± 13 vs. 10.4 ± 12.8 days, P < 0.001). The frequency of abdominal CT findings was significantly higher in patients who did not survive the infection than in patients who were discharged after recovery (41.7% vs. 27.4%, P < 0.001). Increased AA-CAS was found to be associated with a higher risk of ischemic conditions in abdominal CT examinations.CONCLUSIONAbdominal symptoms in patients with COVID-19 are usually associated with positive CT findings. The presence of ischemic findings on CT correlates with poor COVID-19 outcomes. A high AA-CAS is associated with abdominal ischemic findings in patients with COVID-19.

Various benign and malignant pathologies/conditions can cause compression of the extrahepatic biliary system. Anatomical and/or topographic variations of the hepatic artery have long been recognized as a possible cause of the EBS compression. However, anatomical and/or topographic variations, other than the hepatic artery's, should also be considered during the evaluation of the EBS compression. We, herein, report a unique case of the distal common bile duct compression by tortuous and enlarged inferior pancreaticoduodenal artery branches due to severe stenosis of the celiac trunk orifice.

PURPOSEThis study aimed to retrospectively evaluate the apparent diffusion coefficient (ADC) histograms in predicting chemoradiotherapy (CRT) response in patients with locally advanced rectal cancer (LARC).METHODSA total of 51 patients who underwent surgery in our institution for rectal cancer following neoadjuvant CRT between November 2013 and July 2019 were enrolled. Conventional magnetic resonance (MR) and diffusion-weighted images obtained before and after CRT were evaluated retrospectively. All tumor-containing regions of interests were drawn in 3 selected axial images, and special software for histogram analysis was used to evaluate ADC distribution. ADC cutoff values from post-CRT ADC histogram were calculated from receiver operating characteristic (ROC) analysis for evaluating CRT response.RESULTSIn histopathological analysis, 5 patients (9.8%) had minimal response (group 1), 31 patients (60.8%) had partial response (group 2), and 15 patients (29.4%) had complete or almost complete response (group 3). In the ADC histogram, minimum, maximum, 10th, 25th, 50th, 75th, and 90th percentile, mean ADC values, and skewness values of groups 2 and 3 showed significant changes before and after CRT, but no difference was found within group 1 values. The mean, 25th, 50th, 75th percent ADC values after CRT and skewness, and kurtosis values were significantly different between group 1 and group 3. Skewness value from the ADC histogram in postCRT magnetic resonance imaging had the best diagnostic performance with an area under the ROC curve of 0.851 (P =.003) for detecting group 3. The skewness cutoff calculated from the ROC analysis was 0.210 for evaluating CRT response. The sensitivity and specificity of the cut-off value were 100% and 61.4%, respectively.CONCLUSIONThe ADC histogram analysis seems to have potential application in predicting response to neoadjuvant CRT in patients with locally advanced rectal cancer.

PURPOSEWe aimed to evaluate the spectrum of magnetic resonance cholangiopancreatography (MRCP) findings in patients with ectopic opening of the common bile duct (CBD) into the duodenal bulb and to determine the effectiveness of the MRCP technique in diagnosis.METHODSMorphologic and morphometric MRCP/MRI features in 16 patients and 36 controls were retrospectively analyzed by 2 radiologists. The frequency of MRCP findings was determined. The significance of the difference between the MRCP observations in patients and controls was evaluated statistically and the diagnostic effectiveness of MRCP was investigated.RESULTSHook-shaped ending of CBD and bulbar deformity were the most frequent morphologic findings seen on MRCP in the ectopic bulbar opening. Mean pylorus-papilla distance and mean CBD length were significantly shorter and the median diameter of CBD was significantly larger than the control group (patients: 28.6 ± 15.3 mm, 33.7 ± 12.8 mm, 8.6 (2-16) mm; controls: 66.7 ± 11.7 mm, 50.3 ± 14.4 mm, 3.2 (1.5-10) mm, P < .001, respectively). Receiver operating curve analysis showed sensitivity and specificity of MRCP in the diagnosis to be 87.5% and 100%, respectively, if any 3 of the 4 signs (hook-shaped ending of CBD, bulbar deformity, large, and short CBD) were present in a patient whose pylorus-papilla distance was

PURPOSENonalcoholic fatty liver disease (NAFLD) can progress to liver cirrhosis and is predicted to become the most frequent indication for liver transplantation in the near future. Noninvasive assessment of NAFLD is important for diagnosis and patient management. This study aims to prospectively determine the liver stiffness and T1 and T2 values in patients with NAFLD and to compare the diagnostic performance of magnetic resonance elastography (MRE) and mapping techniques in relation to the proton density fat fraction (PDFF).METHODSEighty-three patients with NAFLD and 26 participants with normal livers were imaged with a 1.5 T scanner. PDFF measurements obtained from the multiecho Dixon technique were used to quantify the liver fat. MRE, native T1 mapping (modified Look-Locker inversion recovery [MOLLI] schemes 5(3)3, 3(3)3(3)5, and 3(2)3(2)5 and the B1-corrected variable flip angle [VFA] method), and T2 mapping values were correlated with PDFF. The diagnostic performance of MRE and the mapping techniques were analyzed and compared.RESULTST1 values measured with the MOLLI schemes and the B1-corrected VFA (P < 0.001), and the stiffness values from MRE (P = 0.047) were significantly higher in the NAFLD group. No significant difference was found between the groups in terms of T2 values (P = 0.127). In differentiation of the NAFLD and control groups, the B1-corrected VFA technique had slightly higher accuracy and area under the curve (AUC) than the MOLLI schemes. In the NAFLD group, there was a good correlation between the PDFF, MOLLI 3(3)3(3)5 and 3(2)3(2)5, and VFA T1 measurements (r=0.732; r=0.735; r=0.716, P < 0.001, respectively).CONCLUSIONLiver T1 mapping techniques have the potential to distinguish steatotic from nonsteatotic livers, and T1 values seem to have a strong correlation with the liver fat content.

Magnetic resonance elastography (MRE) is a constantly advancing technique for assessment of stiffness of tissues with newer technology and sequences. It is being increasingly used for the assessment of liver fibrosis. In this article, we discuss the advantages of MRE over biopsy and noninvasive methods such as US elastography in the assessment of liver fibrosis. Image acquisition and interpretation of liver MRE is also discussed.

PURPOSE:We aimed to evaluate the frequency of bile duct branching pattern variations at the hepatic confluence in patients with pancreas divisum (PD).METHODS:A search was performed through the hospital database using the keyword “pancreas divisum” to identify patients. The magnetic resonance cholangiopancreatography (MRCP) images of 137 patients who were diagnosed with PD between August 2011 and November 2016 were retrospectively analyzed for the presence of bile duct variations. A control group of 137 patients without PD was established among patients investigated during the same period. Variations of the biliary tract were grouped into seven types according to the McSweeney et al. classification.RESULTS:Biliary tract variations were detected in 103 of a total of 274 patients. Fifty-eight PD patients (42.3%) and 45 control patients (32.8%) had bile duct variation at the hepatic confluence level. The patients with PD were more likely to have biliary tract variation compared with the control group; however, it was not statistically significant (P = 0.105). The most common variation in PD patients was type 3a variation (16.8%).CONCLUSION:MRCP studies showed atypical bile duct confluence pattern in nearly half of both PD patients and controls. There was no statistically significant difference in the frequency of anatomic variations at bile duct confluence in patients with PD versus those without PD. Derivation of these structures from different outpouchings in early embryological life may explain this insignificant difference.

PURPOSE:We aimed to draw attention to the lymph nodes at the inferior gluteal and ischioanal regions and evaluate the lesions accompanying them using 3.0 T magnetic resonance imaging (MRI).METHODS:In total, 22 patients (15 men, 7 women; mean age, 50±11.2 years; age range, 32–71 years) were included in this study. The patients’ medical records were reviewed. MRI data were reviewed on a picture archiving and communication system workstation by two radiologists in consensus. Lymph node location, laterality, number, and size were documented.RESULTS:The primary disorders causing the enlargement of inferior gluteal lymph nodes (n=16) were perianal fistula of cryptoglandular origin (n=5), perianal fistula associated with Crohn’s disease (n=2), decubitus ulcers (n=2), presacral abscess (n=1), non-Hodgkin lymphoma (n=2), prostate cancer invading urethra and anorectal junction (n=1), endometrium cancer invading the urethra and vagina (n=1), and anal cancer (n=2). The pathologies causing the enlargement of ischioanal lymph nodes (n=6) were perianal fistula of cryptoglandular origin (n=4), subcutaneous inflammation of gluteal region related to Crohn’s disease (n=1), and prostate cancer (n=1).CONCLUSION:The infectious and neoplastic lesions involving the anal canal, distal rectum, gluteal region, prostate, and urethra are the possible causes of inferior gluteal and ischioanal lymph node enlargement. Lymphoproliferative diseases can also affect these node groups. MRI is an important method to identify enlarged inferior gluteal and ischioanal lymph nodes and define associated findings.

PURPOSE:The aim of this study was to retrospectively assess the correlation between minimum apparent diffusion coefficient (ADCmin) values obtained from diffusion-weighted magnetic resonance imaging (MRI) and maximum standardized uptake values (SUVmax) obtained from positron emission tomography-computed tomography (PET-CT) in rectal cancer. MATERIALS AND METHODS: Forty-one patients with pathologically confirmed rectal adenocarcinoma were included in this study. For preoperative staging, PET-CT and pelvic MRI with diffusion-weighted imaging were performed within one week (mean time interval, 3±1 day). For ADC measurements, the region of interest (ROI) was manually drawn along the border of each hyperintense tumor on b=1000 s/mm2 images. After repeating this procedure on each consecutive tumor-containing slice to cover the entire tumoral area, ROIs were copied to ADC maps. ADCmin was determined as the lowest ADC value among all ROIs in each tumor. For SUVmax measurements, whole-body images were assessed visually on transaxial, sagittal, and coronal images. ROIs were determined from the lesions observed on each slice, and SUVmax values were calculated automatically. The mean values of ADCmin and SUVmax were compared using Spearman’s test. RESULTS:The mean ADCmin was 0.62±0.19×10-3 mm2/s (range, 0.368–1.227×10-3 mm2/s), the mean SUVmax was 20.07±9.3 (range, 4.3–49.5). A significant negative correlation was found between ADCmin and SUVmax (r=-0.347; P = 0.026). CONCLUSION:There was a significant negative correlation between the ADCmin and SUVmax values in rectal adenocarcinomas.

We present three patients with Behçet’s disease associated with intracardiac thrombus and pulmonary vascular involvement. One of these patients had also Budd-Chiari syndrome. All patients were treated with corticosteroid plus monthly intravenous cyclophosphamide as first line treatment and with no recurrences. Immunosuppressive therapy was successful in the treatment of intracardiac thrombus and also in the regression of pulmonary vascular thromboses in these patients. Intracardiac thrombus in Behçet’s disease is rarely seen. Behçet’s disease should be remembered in the differential diagnosis of the patients with intracardiac mass, especially in patients from the Mediterranean and Middle East populations.

Adrenal gland disorders can be asymptomatic and detected incidentally via imaging techniques such as ultrasound, computed tomography (CT), positron emission tomography, and magnetic resonance imaging. Fusion anomaly is a condition that can be attributed to errors in the developmental process and may be detected via these imaging modalities. We present a case of butterfly adrenal gland in a 61-year-old man with CT and magnetic resonance images. In our patient, this anomaly is also accompanied by unilateral renal agenesis and a diaphragmatic defect. Positron emission tomography-CT, contrast-enhanced CT, and magnetic resonance images are presented. To the best of our knowledge, this is the second case in which coexistence of unilateral renal agenesis and butterfly adrenal gland anomaly in an adult patient has been documented. Keywords: Butterfly adrenal gland, Unilateral renal agenesis