Assessing hepatic steatosis by magnetic resonance in potential living liver donors.

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.

Reply to Perrella et al. Coming Back to the Basics. Comment on "Cangir et al. A CT-Based Radiomic Signature for the Differentiation of Pulmonary Hamartomas from Carcinoid Tumors. Diagnostics 2022, 12, 416".

We thank to Dr. Perrella and and his fellow authors for your kind letter and thoughtful comments [...].

Three in one: A case presented with multiloculated thymic cyst, thymic Hodgkin lymphoma and pericardial cyst.

Multiloculated thymic cyst is a cystic reaction of medullary epithelium to inflammatory process. In most cases, the exact cause of the inflammation is not known. Hodgkin lymphoma and multiloculated thymic cyst coexistence is a rare condition and may cause significant diagnostic difficulties. Herein, we present a rare case who underwent surgery for multiloculated thymic cyst and was subsequently diagnosed with Hodgkin lymphoma and had a concurrent pericardial cyst.

Evaluation of abdominal computed tomography findings in patients with COVID-19: a multicenter study

PURPOSE: To 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. METHODS: This 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. RESULTS: Ischemic 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. CONCLUSION: Abdominal 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.

Can CT Pelvimetry Be Used to Predict Circumferential Resection Margin Positivity in Laparoscopic Resection of Middle and Lower Rectum Cancer?

Background Previous studies have shown that pelvimetry can be valuable in predicting surgical difficulties in rectal cancer operations. However, its usability in predicting circumferential resection margin (CRM) involvement remains debatable. This study investigated the factors affecting CRM status and the importance of computed tomography (CT) pelvimetry in predicting CRM involvement in laparoscopic resection of middle and lower rectal cancer. Methodology In this study, we retrospectively investigated the data of 111 patients who underwent a laparoscopic operation for middle and lower rectum cancer at Ankara University Faculty of Medicine, Department of Surgical Oncology between January 2014 and January 2020. The predictive value of CT pelvimetry and other variables on the CRM status was analyzed. Results The following four pelvic parameters differed significantly between the genders: transverse diameter of the pelvic inlet (p = 0.024), anteroposterior diameter of the pelvic outlet (p = 0.003), transverse diameter of the pelvic outlet (p < 0.001), and pelvic depth (p < 0.001). The effect of pelvic anatomic parameters on CRM involvement was not found to be significant. It was found that tumor height from the anal verge (p = 0.004), tumor size (p < 0.001), and gender (p = 0.033) were significant risk factors for CRM involvement. Survival was poor in patients with male gender (p = 0.032), perineural invasion (p < 0.001), and grade 3 tumor. Conclusions In this study, no benefit was found in predicting CRM positivity from CT pelvimetry in the laparoscopic resection of middle and lower rectal cancer. Besides, tumor height from the anal verge, tumor size, and gender were important factors for CRM positivity. Although our study sheds light on this issue, prospective randomized studies with larger sample sizes are needed.

A CT-Based Radiomic Signature for the Differentiation of Pulmonary Hamartomas from Carcinoid Tumors.

Radiomics is a new image processing technology developed in recent years. In this study, CT radiomic features are evaluated to differentiate pulmonary hamartomas (PHs) from pulmonary carcinoid tumors (PCTs). A total of 138 patients (78 PCTs and 60 PHs) were evaluated. The Radcloud platform (Huiying Medical Technology Co., Ltd., Beijing, China) was used for managing the data, clinical data, and subsequent radiomics analysis. Two hand-crafted radiomics models are prepared in this study: the first model includes the data regarding all of the patients to differentiate between the groups; the second model includes 78 PCTs and 38 PHs without signs of fat tissue. The separation of the training and validation datasets was performed randomly using an (8:2) ratio and 620 random seeds. The results revealed that the MLP method (RF) was best for PH (AUC = 0.999) and PCT (AUC = 0.999) for the first model (AUC = 0.836), and PC (AUC = 0.836) in the test set for the second model. Radiomics tumor features derived from CT images are useful to differentiate the carcinoid tumors from hamartomas with high accuracy. Radiomics features may be used to differentiate PHs from PCTs with high levels of accuracy, even without the presence of fat on the CT. Advances in knowledge: CT-based radiomic holds great promise for a more accurate preoperative diagnosis of solitary pulmonary nodules (SPNs).

Biphasic split-bolus injection protocol for routine contrast-enhanced chest CT: comparison with conventional early-phase single bolus technique.

OBJECTIVES: To present a routine contrast-enhanced chest CT protocol with a split-bolus injection technique achieving combined early- and delayed phase images with a single aquisition, and to compare this technique with a conventional early-phase single-bolus chest CT protocol we formerly used at our institution, in terms of attenuation of great thoracic vessels, pleura, included hepatic and portal venous enhancement, contrast-related artifacts, and image quality. METHODS: A total of 202 patients, who underwent routine contrast-enhanced chest CT examination aquired with either conventional early-phase single-bolus technique (group A,n = 102) or biphasic split-bolus protocol (group B,n = 100), were retrospectively included. Attenuation measurements were made by two radiologists independently on mediastinal window settings using a circular ROI at the following sites: main pulmonary artery (PA) at its bifurcation level, thoracal aorta (TA) at the level of MPA bifurcation,portal vein (PV) at porta hepatis, left and right hepatic lobe, and if present, thickened pleura (>2 mm) at the level with the most intense enhancement. Respective normalized enhancement values were also calculated. Contrast-related artifacts were graded and qualitative evaluation of mediastinal lymph nodes was performed by both reviewers independently. Background noise was measured and contrast-to-noise ratios (CNRs) of the liver and TA were calculated. RESULTS: While enhancement of thoracic vessels and normalised MPA enhancement did not differ significantly between both groups (p > 0.05), enhancement and normalised enhancement of pleura, liver parenchyma and PV was significantly greater in group B (p < 0.001). Perivenous artifacts limiting evaluation were less frequent in group B than in A and mediastinal lymph nodes were judged to be evaluated worse in group A than in group B with an excellent agreement between both observers. No significant difference was detected in CNRTA (p = 0.633), whereas CNR liver was higher in group B (p < 0.001). CONCLUSION: Our split-bolus chest CT injection protocol enables simultaneous enhancement for both vascular structures and soft tissues, and thus, might raise diagnostic confidence without the need of multiple acquisitions. ADVANCES IN KNOWLEDGE: We think that this CT protocol might also be a promising alternative in lung cancer staging, where combined contrast-enhanced CT of the chest and abdomen is indicated. We therefore suggest to further evaluate its diagnostic utility in this setting, in particular in comparison with a late delayed chest-upper abdominal CT imaging protocol.

A comparison of the fusion model of deep learning neural networks with human observation for lung nodule detection and classification.

OBJECTIVES: To compare the diagnostic performance of a newly developed artificial intelligence (AI) algorithm derived from the fusion of convolution neural networks (CNN) versus human observers in the estimation of malignancy risk in pulmonary nodules. METHODS: The study population consists of 158 nodules from 158 patients. All nodules (81 benign and 77 malignant) were determined to be malignant or benign by a radiologist based on pathologic assessment and/or follow-up imaging. Two radiologists and an AI platform analyzed the nodules based on the Lung-RADS classification. The two observers also noted the size, location, and morphologic features of the nodules. An intraclass correlation coefficient was calculated for both observers and the AI; ROC curve analysis was performed to determine diagnostic performances. RESULTS: Nodule size, presence of spiculation, and presence of fat were significantly different between the malignant and benign nodules (p < 0.001, for all three). Eighteen (11.3%) nodules were not detected and analyzed by the AI. Observer 1, observer 2, and the AI had an AUC of 0.917 ± 0.023, 0.870 ± 0.033, and 0.790 ± 0.037 in the ROC analysis of malignity probability, respectively. The observers were in almost perfect agreement for localization, nodule size, and lung-RADS classification [κ (95% CI)=0.984 (0.961-1.000), 0.978 (0.970-0.984), and 0.924 (0.878-0.970), respectively]. CONCLUSION: The performance of the fusion AI algorithm in estimating the risk of malignancy was slightly lower than the performance of the observers. Fusion AI algorithms might be applied in an assisting role, especially for inexperienced radiologists. ADVANCES IN KNOWLEDGE: In this study, we proposed a fusion model using four state-of-art object detectors for lung nodule detection and discrimination. The use of fusion of deep learning neural networks might be used in a supportive role for radiologists when interpreting lung nodule discrimination.

Prognostic implications of visceral obesity on gastric adenocarcinoma: does it really matter?

PURPOSE: To evaluate the association of visceral adiposity measured on computed tomography (CT) in preoperative period with lymph node (LN) metastasis and overall survival in gastric adenocarcinoma patients. METHODS: Preoperative CT scans of 246 gastric adenocarcinoma patients who did not receive neoadjuvant chemoradiotherapy were evaluated. Visceral fat area (VFA), subcutaneous fat area (SFA) and Total fat area (TFA), VFA/TFA ratio were quantified by CT. VFA/TFA > 29% was defined as visceral obesity. The differentiation, t-stage, n-stage and the number of harvested-metastatic LNs were noted. The maximum thickness of tumor and localization were recorded from CT. Chi-square, Student's t-test, multiple Cox regression, Spearman's correlation coefficient, and Kaplan-Meier algorithm were performed. RESULTS: The overall survival (OS) rates and N-stage were not different significantly between viscerally obese and non-obese group (p = 0.994, p = 0.325). The number of metastatic LNs were weakly inversely correlated with VFA (r = -0.144, p = 0.024). Univariate analysis revealed no significant association between visceral obesity and OS or LN metastasis (p = 0.377, p = 0.736). In multivariate analyses, OS was significantly associated with poorly differentiation (HR = 1.72, 95% CI =1.04-2.84, p = 0.035), higher pathologic T and N stage (T4 vs T1 + T2 HR = 2.67, 95% CI =1.18-6.04, p = 0.019; T3 vs T1 + T2 HR = 1.98, 95% CI = 0.90-4.33, p = 0.089; N3b vs N0 HR = 2.97, 95% CI1.45-6.0, p = 0.003; N3 (3a+ 3b) vs N0 HR = 2.24 95% CI =1.15-4.36, p = 0.018). CONCLUSION: Visceral obesity may not be a prognostic factor in resectable gastric adenocarcinoma patients.

Complete resections of giant thorax masses and experienced difficulties.

INTRODUCTION: Thoracic giant masses do not have a clear definition. In some publications, giant thoracic mass definition is used in tumors whose long axis is> 10 cm and in other publications covering more than 50% of the hemithorax. In this study, demographic data of patients with a massive resectable giant thoracic mass and the difficulties and experiences experienced in the peroperative process were reviewed with a general perspective. MATERIALS AND METHODS: 14 giant intrathoracic masses operated at the department of Thoracic Surgery, School of Medicine, Ankara University were included in the study. The masses occupying more than half of the hemithorax and mediastinal lesions with a long axis of 15 cm or larger radiologically were included and evaluated. RESULT: 9 (64.3%) of our patients were male and 9 (35.7%) were female. The average age was 49.2 ± 17.1(between18-68). The tumor localizations of our patients were determined as 9 (64.2%) hemithorax and 5 (35.8%) mediastinal. When the radiological and intraoperative dimensions were examined separately, it was observed that the mean of long axis of CT image is average 18 ± 3.8 cm (between 12 cm and 26 cm), and the mean of long axis of specimen is average 18.14 ± 3.6 cm (between 15 cm and 23 cm). The heaviest mass was average 844 ± 473 g (350 g-2204 g). CONCLUSIONS: The surgical maneuvers and hence the excision of giant masses become difficult to operate due to the narrow localization of the masses and the frequent invasions of adjacent vascular structures and nerve tissues. However, complete resection of these slowly growing and generally encapsulated masses can provide the cure.

The Impact of Arterial Phase on the Detection of Cervical Lymph Node Metastasis From Papillary Thyroid Carcinoma: A Quantitative Evaluation on Multiphasic Computed Tomography.

OBJECTIVE: The purpose of this study was to assess the diagnostic performance of multiphasic computed tomography (CT) in the discrimination of metastatic lymph nodes (LNs) of papillary thyroid cancer by using quantitative parameters. METHODS: This study enrolled 272 pathologically proven metastatic and benign LNs. Multiphasic CT was utilized by using nonenhanced, arterial (25-second delay), and venous (80-second delay) phases. Mean tissue attenuation values (MAVs) of metastatic and benign LNs were measured, and normalized MAV (common carotid artery and paraspinal muscle) and wash-in and wash-out percentages were also calculated. RESULTS: The arterial phase showed the highest diagnostic performance in differentiation (area under the curve ± standard error, 0.97 ± 0.02; 95% confidence interval, 0.94-1.0; P < 0.001). Cutoff values for MAVs, normalized MAVs, and wash-in and wash-out percentages to predict metastatic LNs were calculated as 109 HU, 0.33, 1.93, 122.5, and -5.6 (sensitivity: 93.4%, 93.3%, 90.4%, 94.1%, and 97.8%, and specificity: 99.3%, 90.4%, 98.5%, 92.6%, and 99.3%, respectively). CONCLUSIONS: Early-phase enhanced CT and the use of quantitative parameters derived from multiphasic CT improve the detection of cervical lymph node metastasis from papillary thyroid cancer.

Partial anomalous pulmonary venous connection detected during right pneumonectomy.

Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital anomaly. Generally, it is seen on the right side and is associated with an atrial septal defect. Herein, we present a case of a 50-year-old male patient with a supracardiac type PAPVC detected during pneumonectomy for a right hilar mass. This is the second case report in the literature presenting surgical treatment of both lung cancer and PAPVC using pneumonectomy. Thoracic surgeons should be aware of this anomaly when they are planning to perform a major lung resection. If PAPVC and lung cancer are in the same lobe, anatomical lung resections including pneumonectomy can be safely performed.

The relation of CT quantified pancreatic fat index with visceral adiposity and hepatic steatosis.

OBJECTIVES: The purpose of this study was to investigate the relation between pancreatic steatosis and visceral adiposity. Furthermore, the study sought to explore the association between pancreatic steatosis, pancreas volume, hepatic steatosis, age, and sex in adults without prior history of pancreatic disease. The research also served to define a cut-off value of visceral fat tissue area (VFA) predicting fatty pancreas. MATERIAL AND METHODS: CT scans of 98 living-liver donor transplant patients without prior history of pancreatic disease were evaluated for the presence of fatty pancreas. Pancreas volume, VFA, subcutaneous-total FA, VFA/TFA ratios of the patients with and without fatty pancreas were quantified with a semi-automated model on CT. Coexistence of hepatic steatosis was also recorded. RESULTS: VFA, TFA and VFA/TFA were significantly greater in the fatty group (p<0.001, p<0.001, p<0.001; respectively), and pancreatic steatosis was moderately correlated with VFA, VFA/TFA and TFA with the highest correlation coefficient with VFA (r=-0.715, r=-0.605, r=-0.573, respectively; p<0.001 for all). A cut-off value of VFA ≥ 107.2 cm2 estimates pancreatic steatosis with a sensitivity and specificity of 90% (95% CI=77-96%) and 87.9% (95% CI=77%-94%), respectively. Pancreas volume was higher in the fatty-group with a mean value of 86.5±17.3 mL (range; 58-119.2 mL, p=0.097). In multiple logistic regression analyses, pancreatic steatosis was significantly associated with VFA and the male sex (OR=58.2, 95% CI=12.2-277.1, p<0.001; OR=11.4, 95% CI=2.1-63.4, p<0.001; respectively). 77.5% of the fatty pancreas subjects had co-existing hepatic steatosis. CONCLUSION: Pancreatic steatosis is related to higher VFA, VFA/TFA and hepatic steatosis. A cut-off value of VFA ≥ 107.2 cm2 may predict pancreatic steatosis.

Evaluation of Extramural Venous Invasion by Diffusion-Weighted Magnetic Resonance Imaging and Computed Tomography in Rectal Adenocarcinoma.

PURPOSE: The aim of this study is to evaluate the diagnostic contribution of diffusion-weighted magnetic resonance imaging (MRI) and computed tomography (CT) to distinguish extramural venous invasion (EMVI) in rectal adenocarcinoma. MATERIALS AND METHODS: Fifty-eight patients who had been diagnosed with rectal adenocarcinoma (30 patients with EMVI and 28 patients without EMVI) were enrolled in the study. Apparent diffusion coefficient (ADC) values of the tumour and the EMVI (+) vein, the lengths of the tumours were measured on MRI. The diameters of the superior rectal vein (SRV)-inferior mesenteric vein (IMV) and distant metastatic spread were evaluated on CT. The ability of these findings to detect EMVI was assessed using receiver operating characteristic (ROC) analysis. Pathology was accepted as the reference test for EMVI. RESULTS: Mean diameters of the SRV (4.9 ± 0.9 mm vs 3.7 ± 0.8 mm) and IMV (6.9 ± 0.8 mm vs 5.4 ± 0.9 mm) were significantly larger (P < .001) and tumour ADC values were significantly lower (0.926 ± 0.281 × 10-3 mm2/s vs 1.026 ± 0.246 × 10-3 mm2/s; P = .032) in EMVI (+) patients. Diameters of 3.95 mm for the SRV (area under the curve [AUC] ± standard error [SE]: 0.851 ± 0.051, P < .001, sensitivity: 93.3%, specificity: 67.9%) and 5.95 mm for the IMV (AUC ± SE: 0.893 ± 0.040, P < .001, sensitivity: 93.3%, specificity: 71.4%) and an ADC value of 0.929 × 10-3 mm2/s (AUC ± SE: 0.664 ± 0.072, P = .032 sensitivity: 76.7%, specificity: 57.1%) were found to be cutoff values, determined by ROC analysis, for detection of EMVI. Distant metastases were significantly more prevalent in EMVI (+) patients (P < .001). CONCLUSION: The measurement of ADC values and SRV-IMV diameters seems to have contribution for diagnosis of EMVI in rectal adenocarcinoma. EMVI (+) patients appear to have higher risks of distant metastases at diagnosis.

Backwash ileitis in ulcerative colitis: Are there MR enterographic features that distinguish it from Crohn disease?

OBJECTIVE: To reveal the MR enterography (MRE) findings that distinguish backwash ileitis (BWI) from terminal ileitis due to Crohn's disease (CD) and to determine the usability of barium studies manifestations (ileocecal valve (ICV) gaping, terminal ileum dilatation) in MRE for the diagnosis of BWI in ulcerative colitis (UC) patients by pointing at the diagnostic performance of these imaging findings. SUBJECTS-METHODS: The study population consisted of patients who were diagnosed as ulcerative colitis (UC), and underwent 1.5 T MRI between August 2011 and November 2017 to rule out small bowel involvement. The matched controls were comprised of Crohn's patients examined at the same period. Ileocolonoscopic/ histopathologic findings were accepted as reference standard. Mural/extramural changes in bowel segments, ileocecal valve (ICV) gaping, terminal ileum dilatation, restricted diffusion and anatomical extent of involvement were evaluated. In UC patients, the association between ICV gaping and terminal ileum dilatation and BWI was assessed by χ2 test. The diagnostic accuracy of these two findings in BWI was determined. RESULTS: Sixty patients were included in the study (30 UC; 30 CD; mean age, 43 years in both groups). Ileocecal valve gaping and terminal ileum dilatation were significantly more frequent among BWI patients (p < 0.001) in UC. Patients with BWI showed a higher rate of pancolitis (88.9%). Median terminal ileum wall thickness was found to be significantly greater in patients with CD (p < 0.001). CONCLUSION: In patients with definite diagnosis of UC, ileocecal valve gaping and terminal ileum dilatation suggest the development of BWI. However, these findings cannot be use to differentiate cause of terminal ileitis in patients with unconfirmed diagnosis and do not give reliable information about the causative factor of ileitis.