Abdominal Radiology最新文献

Purpose: To explore the heterogeneity of the rectal cancer microenvironment (TME) using restricted spectrum imaging (RSI) and investigate its association with tumor stroma and Ki67 as key histopathologic indicators.

Materials and methods: In this prospective study, 66 patients with rectal cancer underwent pretreatment MRI with RSI. The optimal model format was determined by Bayesian Information Criterion (BIC). RSI3-derived parameters (RSI₃-C1, RSI₃-C2, RSI₃-C3) and ADC values were measured and correlated with stroma status, Ki67 expression, and clinicopathological features. The diagnostic performance of these quantitative imaging biomarkers was assessed using receiver operating characteristic (ROC) analysis.

Results: The three-compartment RSI model (RSI₃) was optimal for characterizing rectal cancer (△BIC = 0). RSI₃-C1, RSI₃-C2, and RSI₃-C3 showed significant differences between low-stroma and high-stroma groups (P < 0.05). RSI₃-C2 exhibited the highest accuracy in characterizing stroma status (AUC = 0.800, sensitivity = 79.2%, specificity = 71.4%). All RSI₃ parameters and ADC values differed significantly between low-Ki67 and high-Ki67 groups (P < 0.05). RSI₃-C1 demonstrated the highest accuracy in characterizing Ki67 status (AUC = 0.824, sensitivity = 90.0%, specificity = 69.4%). Significant differences were observed in RSI₃-C3 and ADC values for tumor differentiation (P < 0.05). RSI₃-C3 showed the highest accuracy in characterizing differentiation status (AUC = 0.721, sensitivity = 66.7%, specificity = 83.3%).

Conclusion: RSI₃-derived parameters show potential as non-invasive biomarkers for evaluating TME in rectal cancer. This innovative approach may improve decision-making, leading to better patient outcomes in rectal cancer management.

Objective: The T2* technique in Blood Oxygen Level Dependent Magnetic Resonance Imaging (BOLD-MRI) has been established as a non-invasive standard for quantifying tissue iron levels. This study aims to assess the feasibility of obtaining quantitative iron-sensitive information from conventional MRI T2-weighted imaging (T2WI) sequences, typically used for anatomical rather than quantitative assessments, and to explore its potential as a routine monitoring tool for renal iron levels in diabetic kidney disease (DKD).

Methods: A total of 142 patient imaging data from renal MRI scans were retrospectively analyzed. We measured the kidney and psoas major muscle signal intensity on T2WI sequences and calculated the kidney-to-muscle signal intensity ratio (K/M-SIR) to determine differences across patient groups. Relevant laboratory indices were collected to analyze the correlation between K/M-SIR and laboratory markers.

Results: We included 42 clinically confirmed DKD patients, 47 patients with diabetes but no DKD, and 53 healthy subjects. The K/M-SIR was 2.66 ± 0.49 in DKD patients, 2.94 ± 0.51 in diabetic patients without DKD, and 2.95 ± 0.55 in healthy subjects. There were statistically significant differences in K/M-SIR between DKD patients and healthy subjects (p = 0.008) and between DKD patients and diabetic patients without DKD (p = 0.009). K/M-SIR values were negatively correlated with laboratory indices such as glycated hemoglobin (HbA1c), microalbuminuria (MAU), albumin-to-creatinine ratio (ACR), and 24-hour urinary protein (24 h UP).

Conclusion: The kidney-to-muscle signal intensity ratio (K/M-SIR) derived from routine MRI T2WI sequences is valuable for diagnosing DKD and may serve as a reliable non-invasive marker for assessing renal iron deposition in DKD, potentially aiding in the diagnosis and monitoring of DKD severity.

Objectives: Using contrast-enhanced ultrasound (CEUS) and ultrasound resolution microscopy (URM) imaging, this study aimed to evaluate the relationship between microvascular parameters of small hepatocellular carcinoma (sHCC) (≤ 3 cm) and microscopic histological features, which include vessels encapsulating tumour clusters (VETC), microvascular invasion (MVI), and histological grade.

Methods: Sixteen patients with solitary resected sHCC were prospectively enrolled. CEUS and URM were performed one week before resection. All "ratio" refers to comparisons between the active area (where CEUS microbubble show visible motion track by URM) and the entire lesion. Blood vessel complexity (ratio), blood vessel density (ratio), area (ratio), flow velocity, blood vessel diameter, and perfusion index ("flow velocity" × "vessel ratio") were analysed using URM. The relationships between URM parameters and microscopic histological features (MVI, VETC, and histological grade) were analysed.

Results: There were 5 (31.3%), 8 (50%), and 7 (43.7%) cases of poorly differentiated, MVI-positive, and VETC-positive HCC, respectively. The mean velocity of the entire lesion was higher in the poorly differentiated group than that in the moderately differentiated group (p = 0.026). The complexity ratio (MVI-positive: 1.07 ± 0.03, MVI-negative: 1.03 ± 0.02, p = 0.012), area ratio (MVI-positive: 0.63 ± 0.18, MVI-negative: 0.39 ± 0.16, p = 0.017), and perfusion index (MVI-positive: 8.67 ± 1.88, MVI-negative: 6.42 ± 0.94, p = 0.009) were greater in MVI-positive HCCs. The density ratio (VETC-positive: 1.30 ± 0.19, VETC-negative: 1.10 ± 0.05, p = 0.006) was larger in VETC-positive HCCs.

Conclusion: Higher blood flow velocity and area of HCC lesions, and higher blood vessel complexity and density may be related to microscopic histological features. This relationship might provide a strategy of using URM for preoperative non-invasive diagnostic VETC, MVI, and histological grade in the future.

Purpose: This retrospective study aimed to confirm the safety and long-term efficacy of a single-session combined treatment approach with transcatheter arterial embolization (TAE) and microwave ablation (MWA) for inoperable small-to intermediate-sized hepatocellular carcinomas (HCC), focusing on their combined benefits for improving local control.

Materials and methods: All consecutive patients with up to 2 small-to-intermediate HCC lesions (≤ 5 cm) treated with a combined single-session MWA-TAE approach were enrolled between April 2020 and October 2023. All procedures were performed in two stages: TAE and MWA. Clinical and radiological follow-up was performed 3, 6, and 12 months after treatment.

Results: In the 21 enrolled patients (15 males, mean age 75.9 years), post-procedural contrast-enhanced CT scans confirmed a satisfactory ablation zone in all patients (100%), with minor peri-procedural complications reported in three patients (14%). At the last 12-month follow-up, one patient (8%) displayed local tumor progression, previously classified as LR-TR equivocal at the 6-month follow-up, and half of the patients (6 patients, 50%) exhibited distant tumor progression, predominantly in the form of intra-hepatic recurrence.

Conclusion: The combined approach of TAE and MWA is a promising method to enhance the percutaneous treatment of small to intermediate-sized HCCs with a resulting anatomic ablation area resembling a surgical sub-segmentectomy. This technique can potentially reduce the gap between percutaneous treatment and liver resection outcomes, allowing for a safe and effective option for oncological control in patients with > 3 cm lesions.

Purpose: To evaluate safety and oncologic efficacy of percutaneous microwave ablation (MWA) for treating clinically localized T1b (cT1b) renal cell carcinoma (RCC).

Methods: This single-center retrospective study was performed under a waiver of informed consent. Seventy-four consecutive patients (49M/25F) with 76 cT1b RCC (median tumor diameter 4.5 cm) were treated with percutaneous MWA between 5/2012 and 8/2020. Patients were stratified into two groups by technique, depending on whether antennas were repositioned for additional ablation or not. Primary efficacy, complications, and local tumor progression (LTP) were compared using the Wilcoxon rank sum and Fisher's exact tests. The Kaplan Meier method was used for survival analysis.

Results: Patients were elderly (median age 69.5), obese (median BMI 34.5), and comorbid (Charlson Comorbidity Index = 4). Most tumors were low-grade (grade 1-2) (67/89, 88%) and clear cell RCC was the most common histology (62/76, 82%). A median of three MWA antennas were powered at 65 W for 7 min for treatment. Renal masses were larger (4.6 vs 4.5 cm, p = 0.01) and procedure times longer (100 min vs 80.5 min, p = 0.04) for the antenna reposition cohort (n = 34, 45%). Primary efficacy and high-grade complication rates were 93% and 8%, respectively. The local tumor progression rate (LTP), at a median follow-up was 28.2 months, was 16%. Primary efficacy, low and high-grade complications, change in estimated glomerular filtration rate and LTP were similar between cohorts (p = 0.20-0.55).

Conclusion: Percutaneous MWA for cT1b RCC is safe in elderly and comorbid patients with acceptable oncologic efficacy. Repeat ablation is well-tolerated and can improve oncologic efficacy.

Background: There is a lack of staging systems in pediatric lymphoma to quantify the burden of the disease based on the anatomical extent of lymph nodal distribution.

Purpose: To evaluate the utility of a CECT-based semiquantitative lymph nodal scoring system in predicting histopathological type of childhood lymphoma and response to initial chemotherapy.

Materials and methods: Pre-treatment CECT of abdomen and thorax was performed in children with lymphoma and a Checklist-based reporting template was used to report the lymph nodal involvement. Based on the distribution of lymph nodes, a semi-quantitative scoring system was developed to cover all the locations of thorax and abdomen. Anatomical semiquantitative scoring was done for thorax (score 0-10), abdomen (scores 0-10), and a combined thoraco-abdominal score (0-20) was calculated. Also, the mean scores were compared in patients with complete response(CR) and Non-complete response(NCR) to primary treatment. Decrease in size of all the pathological nodes to < 10 mm in short axis and < 15 mm in long axis was defined as CR.

Results: Fifty patients were included with 35 cases of Hodgkin Lymphoma(HL) and 15 cases of Non-Hodgkin Lymphoma(NHL). Mean abdominal, thoracic, and combined lymph nodal scores were significantly lower in the pre-treatment scan in children with HL (3.5 ± 2.3, 3.3 ± 1.75,and6.89 ± 3.54) compared to NHL (4.8 ± 2.1,5.2 ± 2.8,and10.0 ± 3.96). The mean abdominal, thoracic, and combined lymph nodal scores in the pre-treatment scan was significantly higher in NCR group.

Conclusion: The lymph nodal burden, estimated by semiquantitative abdominal and thoracic scores is significantly higher in lymphoma patients with non-complete response.

Objective: To investigate the potential of multiparametric MRI clear cell likelihood scores (ccLS) for differentiating between fat-poor angiomyolipoma (AML) and clear cell renal cell carcinoma (ccRCC) in subcentimeter Lesions (1 cm or smaller).

Materials and methods: This retrospective study included consecutive patients with subcentimeter renal masses who underwent multiparametric MRI between September 2009 and September 2022 across three hospitals. Clinical and MRI findings were analyzed to differentiate between fat-poor AML and ccRCC. Lesions were categorized using the ccLS and receiver operating characteristic curve analysis was performed to assess ccLS performance.

Results: Thirty-eight patients (mean age: 52 years ± 12; 19 women) with 39 lesions were included. Of the 39 lesions [mean size: 9.1 mm ± 1.0 (range, 6.0-10.0 mm)], 20 (51%) were ccRCC and 19 (49%) were fat-poor AML. Compared to the ccRCC, subcentimeter fat-poor AMLs were more likely to show hypointensity on T2WI (P < 0.001), homogeneous enhancement (P = 0.010), the presence of microscopic fat (P = 0.036), and the absence of a pseudocapsule (P = 0.020). The diagnostic percentage of fat-poor AML was 47% for a ccLS of 1 or 2, and ccRCC accounted for 75% in the ccLS 4 or 5 category. The AUC for discrimination was 0.846 (95% CI: 0.695-0.941, P < 0.001), with a sensitivity of 75.00% (95% CI: 50.9-91.3) and a specificity of 89.47% (95% CI: 66.9-98.7).

Conclusion: Multiparametric MRI clear cell likelihood scores can potentially be used to differentiate between fat-poor AML and ccRCC in lesions 1 cm or smaller.

Purpose: We aimed to develop and validate a combined model integrating radiomic features derived from Contrast-Enhanced Ultrasound (CEUS) images and clinical parameters for preoperative prediction of CK19-positive status in hepatocellular carcinoma (HCC).

Methods: A total of 434 patients who underwent CEUS and surgical resection from January 2020 to December 2023 were included. Patients were randomly divided into a training cohort (n = 304) and a validation cohort (n = 130). Radiomic features were extracted from multiphase CEUS images, including two-dimensional ultrasound (US), arterial, portal venous, and delayed phases, and combined to derive a Radscore model. Subsequently, a Combined Model was constructed using the Radscore and clinical parameters. Model performance was assessed using calibration, discrimination, and clinical utility.

Results: Multivariate logistic regression analysis identified Radscore (OR = 10.054, 95% CI: 5.931-19.120, p < 0.001) and AFP levels > 200 ng/mL (OR = 5.027, 95% CI: 2.089-12.784, p < 0.001) as significant predictors in the combined model. The AUC (Area Under the Curve) for the Combined Model was 0.954 in the training cohort and 0.927 in the validation cohort, compared to 0.939 and 0.917 for the Radscore Model alone. Calibration curves demonstrated strong concordance between predicted and actual outcomes. Decision curve analysis (DCA) showed that both the Radscore Model and the Combined Model exhibited good net benefits across a wide range of threshold values in both the training and validation cohorts.

Conclusion: The Radscore based on CEUS, combined with the serum markers AFP > 200 ng/L to construct a Combined Model, shows good predictive performance for CK19 + hepatocellular carcinoma (HCC).

Background: Layering hyperintensity in the gallbladder is frequently observed on T1-weighted (T1w) magnetic resonance imaging (MRI), but its association with hepatobiliary disorders is not well understood.

Objective: This study aimed to evaluate the prevalence of T1w layering in the gallbladder and its correlation with ultrasound (US) findings and patient characteristics in a cohort with significant liver disease.

Methods: A single-center study from 2015 to 2022 included patients who underwent MRI and abdominal US within one week. Exclusion criteria were poor imaging quality and prior cholecystectomy. MRI findings were correlated with US and analyzed against patient characteristics.

Results: Among 415 patients (mean age 58.3 ± 14.8 years; mean BMI 28.0 ± 4.5 kg/m²), 67% had abnormal liver function tests, with high prevalences of cirrhosis (n = 260), transjugular intrahepatic portosystemic shunt (TIPS) (n = 233), and choledocholithiasis (n = 106). T1w layering was observed in 56% (n = 232) and associated with higher BMI (p = 0.001) and with cholecystolithiasis (p < 0.001), but not with age, sex, or liver disease indicators. T1w layering was predictive of gallbladder sludge on US (odds ratio 17.2, 95% confidence interval 9.87-31.44, p < 0.001), with a sensitivity of 92.7% but moderate specificity (57.9%).

Conclusion: T1w layering on MRI strongly predicts gallbladder sludge detected on US and is associated with increased BMI in this cohort of patients with liver disease. However, the moderate specificity requires cautious interpretation, and our findings suggest that T1w layering may serve as a complementary diagnostic tool.

Background/purpose: To evaluate the advantages of including versus excluding the tumor periphery and combining diffusion-weighted imaging (DWI) with T2-weighted imaging (T2w) for outcome predictions of preoperative radio(chemo)therapy in rectal cancer.

Methods: Four analysis strategies, based on two segmentation methods and two magnetic resonance imaging (MRI) sequences, were evaluated in 106 patients examined with pretreatment MRI. One segmentation method included the tumor periphery in the region of interest (ROI) encompassing the whole tumor (wROI), considered as the reference segmentation approach, and one included only the central part (cROI). Relevant radiomics imaging features were extracted from either T2w alone or from both T2w and DWI and used by a machine learning algorithm for the prediction of pathologic complete response (pCR), neoadjuvant rectal (NAR) score, and disease recurrence. The area under the curve (AUC) was the performance measure. AUCs were compared with a bootstrapping method based on 10⁴ bootstraps.

Results: cROI applied to both T2w and DWI provided the highest numerical prediction of pCR (AUC 0.76), however, not significantly superior to the other strategies (p ≥ 0.138). cROI applied to both T2w and DWI also yielded the highest numerical prediction of NAR score (AUC 0.84), showing advantages over wROI-based analysis strategies (AUC 0.66 and 0.69; p ≤ 0.008). When compared to cROI applied to T2w alone (AUC 0.73), the benefit was borderline statistically significant (p = 0.053). For prediction of disease recurrence, no differences were found between the analysis strategies.

Conclusions: Inclusion of the tumor periphery in radiomic analysis of magnetic resonance images does not improve predictions of the preoperative therapy response in patients with rectal cancer. Excluding tumor periphery while adding DWI to T2w improves prediction of the NAR score, although it does not affect pCR or recurrence prediction.