Abdominal Radiology最新文献

Objectives

Low-keV virtual monoenergetic images on dual-energy CT (DECT) enhance iodine attenuation in inflamed appendiceal walls, but the role in differentiating complicated from uncomplicated appendicitis remains unclear. This is particularly relevant given the shift toward nonoperative management of uncomplicated appendicitis.

Methods

Consecutive adult patients with pathologically confirmed acute appendicitis who underwent preoperative rapid-kVP-switching DECT and appendectomy within 24 h were retrospectively included. Two radiologists reviewed DECT images, including a finding of appendiceal wall enhancement defects, using three series: 50-keV monoenergetic, 120-kVp-equivalent, and combined series, with discrepancies resolved by a third radiologist. Diagnostic performance of three series for differentiating complicated from uncomplicated appendicitis was assessed. Detection rates of appendiceal wall enhancement defects and radiologist confidence among three series were compared.

Results

Among 155 patients (50 men, mean age 47.4±19.0 years), 59 had complicated appendicitis. The combined 50-keV/120-kVp-equivalent series provided balanced sensitivity (83.1%) and specificity (86.5%), with an accuracy of 85.2% in differentiating uncomplicated and complicated appendicitis. Although 50-keV images revealed the most wall enhancement defects (48/122; 39.3%), radiologists’ confidence was significantly higher using the combined series (91.8% vs. 72.1%, p < 0.001).

Conclusions

Low-keV virtual monoenergetic DECT, when combined with 120-kVP-equivalent images, improved the detection of appendiceal wall enhancement defects and increased radiologist confidence in differentiating complicated from uncomplicated appendicitis in adult patients with acute appendicitis.

Magnetic Resonance Urography (MRU) is a comprehensive, non-invasive imaging technique that offers detailed anatomical and functional assessment of the urinary system without radiation exposure. It is particularly valuable in pediatric, pregnant, and renally impaired patients, and in those with CT contrast allergies. Multiparametric MRU sequences can evaluate congenital anomalies, functional obstruction, urothelial tumors, and postoperative anatomy. Advancements in imaging technology such as respiratory gating, compressed sensing, and motion correction, have significantly improved image quality and patient comfort. The introduction of the Vesical Imaging Reporting and Data System (VI-RADS) has standardized bladder cancer staging, aiding in inter-reader reproducibility and treatment planning. This review outlines MRU technique, protocol optimization, artifact mitigation strategies, and specific pediatric and oncologic applications. Illustrative cases highlight the versatility of MRU in clinical practice. With advanced MRI techniques, increasing expertise among radiologists and familiarity among urologists, MRU is emerging as a first-line modality in select urologic conditions.

Objective

To assess the clinical presentation of aortic penetration by inferior vena cava (IVC) filters, as well as common management strategies and clinical outcomes.

Methods

A systematic search of the literature was conducted to identify studies pertaining to aortic penetration by IVC filters published between January 1967 and April 2025.

Results

A total of 35 reports regarding aortic penetration by IVC filters were identified, including a total of 53 patients and 11 types of IVC filters. The median time from filter placement to the diagnosis of aortic penetration was 5.0 years (interquartile range: 1.7, 8.0 years). Of the 53 patients, 28 (52.8%) were symptomatic, 19 (35.9%) were asymptomatic, and 6 (11.3%) had unknown symptomatology. The most frequently reported symptom was abdominal pain (30.2%). Fifteen patients were reported to have experienced one or more of the following complications: aortic pseudoaneurysm (n = 7), arterial thrombosis (n = 5), retroperitoneal hematoma (n = 4), arteriovenous fistula (n = 2), and aortic dissection (n = 1). Of the 53 patients, 36 (67.9%) underwent filter retrieval (endovascular retrieval, n = 24; surgical retrieval, n = 12), 9 (18.0%) underwent repair of the perforated aorta without filter removal, 6 (11.3%) received conservative management, and 2 (4.0%) died of retroperitoneal hematoma.

Conclusions

Aortic penetration by IVC filters is uncommon but potentially life-threatening. Symptomatic patients account for nearly half of all penetrations. For patients demonstrating concomitant penetration into adjacent tissues or visceral organs, surgical retrieval may provide the best option. In asymptomatic patients with no radiologically evident concomitant injuries, endovascular retrieval has been demonstrated to serve as a relatively safe and feasible alternative management strategy.

Purpose

To compare liver parenchymal enhancement and tumor washout on portal and delayed phases between rapid kVp-switching dual-energy CT (DECT) with a low-iodine-dose (LID) contrast medium protocol (350 mg/kg) and conventional single-energy CT (SECT) with a standard-iodine-dose protocol (525 mg/kg), in patients referred for primary liver cancer.

Materials and methods

All consecutive patients referred for primary liver cancer assessment who underwent both SECT with standard iodine dose and DECT with LID protocol were retrospectively reviewed. Relative Liver Enhancement (RLE) and parenchymal contrast-to-noise ratio (pCNR) on portal venous (PVP) and delayed phases were compared between 50 keV virtual monochromatic DECT and SECT images. A sub-analysis at 77 keV was also performed. Quantitative tumor enhancement (QTE) and tumoral contrast-to-noise ratio (tCNR) were compared between techniques in a subset of patients bearing LI-RADS 5 liver tumors.

Results

Seventy-seven patients (mean age 66±9 years) were included and 154 CT scans were analyzed (February 2023-October 2023). RLE and pCNR were significantly higher on 50-keV DECT than on SECT during both PVP (RLE: 1.68 ± 0.45 vs. 0.82 ± 0.18; pCNR: 2.90 ± 1.01 vs. 2.54 ± 0.76; all p < 0.01) and delayed phases (RLE: 1.17 ± 0.41 vs. 0.61 ± 0.19; pCNR: 1.84 ± 0.90 vs. 1.61 ± 0.67; p < 0.05). At 77 keV, RLE and pCNR were similar to SECT. Among thirty-one LR-5 tumors (n = 17 patients), QTE and tCNR were significantly greater on 50-keV DECT than SECT across all phases including PVP (-29.48 ± 16.4 vs. -13.38 ± 11.98 p < 0.001) and delayed phase (-23.48 ± 13.43 vs. -8.14 ± 10.49 p < 0.001).

Conclusion

Rapid kVp-switching DECT at 50-keV DECT VMIs improves liver and tumor contrast on PVP and delayed phase despite a 33% iodine dose reduction, supporting its use in cirrhotic patients.

Purpose

The purpose of this study was to evaluate the clinical effectiveness of MultiVane (MV) sequence, which is a motion correction technique using rotating blades, for patients with uterine endometrial cancer.

Materials and methods

This study enrolled 42 patients with histopathologically confirmed uterine endometrial cancer, who underwent preoperative MRI including sagittal T2-weighted images (T2WI) and contrast-enhanced T1-weighted images (CE-T1WI) acquired using both turbo spin-echo (TSE) and MV sequences with approximately matched acquisition times. Two experienced radiologists independently evaluated all sagittal images. First, the readers assessed the degree of motion artifacts and measured the signal intensity of the tumor and myometrium to calculate the signal-to-noise ratio (SNR) and tumor-to-myometrium contrast ratio (CR). Second, the readers assessed the depth of myometrial invasion on sagittal T2WI and CE-T1WI acquired using TSE and MV sequences. Image quality and diagnostic performance for assessing myometrial invasion were compared between TSE and MV sequences.

Results

Motion artifacts were significantly improved on MV sequence than on TSE sequence (p < 0.01). The SNR and CR were not significantly different between TSE and MV sequences (p > 0.05). Sensitivities, specificities, accuracies, and area under the curve for the diagnosis of myometrial invasion were slightly increased on MV sequence than on TSE sequence, but these differences were not statistically significant (p > 0.05).

Conclusion

MV sequence contributes to the improvement of motion artifacts in the female pelvis without degrading SNR and CR of endometrial cancer and myometrium compared to TSE sequence. MV sequence did not significantly improve the diagnostic performance for assessing myometrial invasion in endometrial cancer, possibly due to the limited imaging plane and small sample size.

Purpose

Polycystic liver disease is the most prevalent extrarenal manifestation of autosomal dominant polycystic kidney disease (ADPKD). Non-obstructive asymptomatic common bile duct (CBD) dilatation has been observed anecdotally on CT scans, but CT is not optimal for biliary visualization. Here, we measured CBD diameter on T2-weighted MRI in ADPKD subjects to determine if CBD dilatation is associated with ADPKD.

Methods

CBD diameter was measured retrospectively on ADPKD subjects (n = 254) and on age- and sex-matched controls without ADPKD (n = 254) who underwent abdominal MRI. CBD diameter in these groups was compared and correlated with clinical, laboratory and magnetic resonance imaging (MRI) features, including organ volumes and cyst burden.

Results

CBD median diameter [interquartile range, IQR, 25%, 75%] was 22% larger in ADPKD compared to controls (5.6 [4.7, 6.9] mm vs. 4.6 [3.9, 5.4] mm, p < 0.001). CBD diameter measurements had excellent inter-observer agreement (Intraclass correlation coefficient = 0.92). Thirteen (5.1%) ADPKD subjects had a CBD diameter ≥ 10 mm compared to 1 (0.4%) control subject (p < 0.001). Multivariable analysis found the presence of PKD1 or PKD2 mutation (beta = 1.5, P < 0.001) and age (beta = 0.04, p < 0.001) to be associated with increased CBD diameter and serum albumin associated with decreased CBD diameter (beta=-0.39, p < 0.001).

Conclusion

ADPKD subjects had 22% larger CBD diameters than in non-ADPKD controls and were more likely to have CBD dilatation ≥ 10 mm without CBD obstruction. Awareness of this association of non-obstructive CBD dilatation with ADPKD may limit unnecessary diagnostic testing.

Purpose

This study aimed to evaluate the value of contrast-enhanced ultrasound (CEUS) in the differential diagnosis of gallbladder cholesterol polyps and adenomas.

Methods

Sixty-seven patients with gallbladder polyps (GBPs) measuring ≥ 10 mm in diameter were consecutively enrolled. All patients underwent two-dimensional ultrasound, color Doppler flow imaging (CDFI), and CEUS before surgical treatment. The size of gallbladder, gallbladder contraction function, gallstones and cholecystitis were also included in the analysis.

Results

Among the 59 patients in the final analysis, 43 cases (72.9%) were diagnosed as gallbladder cholesterol polyps and 16 cases (27.1%) as gallbladder adenomas, all confirmed by pathology. Compared with the cholesterol polyp group, the adenoma group exhibited significantly larger lesion size, a higher prevalence of solitary lesions, and more frequent regular morphology or nodular surface with homogeneous internal echotexture. A majority of cases showed positive CDFI findings. Additionally, the adenoma group demonstrated earlier enhancement onset, greater enhancement intensity, more frequent branch vessels in the arterial phase, and a lower incidence of cholecystitis. No significant differences were found between the two groups in terms of age, sex, lesion basal width, gallbladder volume, cholecystolithiasis, or gallbladder contraction function. Logistic regression analysis identified solitary lesions, higher enhancement degree, presence of branch vessels in the arterial phase, and smooth or nodular surface morphology post-enhancement as independent risk factors for gallbladder adenomas.

Conclusion

CEUS is effective in evaluating GBP perfusion and clearly delineating lesion morphology. Morphological and perfusion characteristics in CEUS could provide valuable differentiation between gallbladder cholesterol polyps and adenomas. These findings may enhance diagnostic accuracy and help reduce unnecessary surgical intervention for large (≥ 10 mm) gallbladder cholesterol polyps.

Purpose

This study evaluates the predictive ability of multiparametric dual-energy computed tomography (multi-DECT) radiomics for tumor budding (TB) grade and prognosis in patients with colorectal cancer (CRC).

Methods

This study comprised 510 CRC patients at two institutions. The radiomics features of multi-DECT images (including polyenergetic, virtual monoenergetic, iodine concentration [IC], and effective atomic number images) were screened to build radiomics models utilizing nine machine learning (ML) algorithms. An ML-based fusion model comprising clinical-radiological variables and radiomics features was developed. The assessment of model performance was conducted through the area under the receiver operating characteristic curve (AUC), while the model’s interpretability was assessed by shapley additive explanation (SHAP). The prognostic significance of the fusion model was determined via survival analysis.

Results

The CT-reported lymph node status and normalized IC were used to develop a clinical-radiological model. Among the nine examined ML algorithms, the extreme gradient boosting (XGB) algorithm performed best. The XGB-based fusion model containing multi-DECT radiomics features outperformed the clinical-radiological model in predicting TB grade, demonstrating superior AUCs of 0.969 in the training cohort, 0.934 in the internal validation cohort, and 0.897 in the external validation cohort. The SHAP analysis identified variables influencing model predictions. Patients with a model-predicted high TB grade had worse recurrence-free survival (RFS) in both the training (P < 0.001) and internal validation (P = 0.016) cohorts.

Conclusion

The XGB-based fusion model using multi-DECT radiomics could serve as a non-invasive tool to predict TB grade and RFS in patients with CRC preoperatively.

Objectives

To evaluate the value of dual-layer spectral detector CT (DLCT) for predicting Ki-67 proliferation status and p53 mutations in pancreatic ductal adenocarcinoma (PDAC).

Materials & methods

This retrospective study included untreated patients with pathologically confirmed PDAC who underwent DLCT between June 2019 and September 2023. Independent relevant clinical-radiological features and quantitative parameters for predicting Ki-67 proliferation status and p53 mutations were identified using multivariate logistic regression analysis. The diagnostic performances of independent variables were evaluated using receiver operating characteristic curves.

Results

We included 92 patients (60.19 ± 11.22 years old, 61 males). There were 40 patients with high Ki-67 expression (Ki-67 ≥ 25%) and 43 patients positive for p53 mutation. The radiologists showed substantial or near-perfect inter- and intra-observer agreement in evaluating quantitative parameters. Normalised iodine concentration in the arterial phase (nICa) was the only independent predictor of Ki-67 proliferation status (p < 0.001; adjusted odds ratio [OR], 2.33; 95% confidence interval [CI]: 1.46, 3.74; cut-off, 0.0910) and p53 mutations (p < 0.001; adjusted OR, 1.35; 95% CI: 1.07, 1.71; cut-off, 0.0905) according to the multivariate logistic analysis. nICa showed satisfactory performance when using the chosen rounded cut-off value of 0.090 (easily applicable in clinical practice) in predicting Ki-67 proliferation (area under the receiver operating characteristic curve [AUC], 0.812; sensitivity, 87.5%; specificity, 75.0%) and p53 mutations (AUC, 0.731; sensitivity, 76.7%; specificity, 69.4%).

Conclusion

The DLCT parameter nICa enables simultaneous and non-invasive prediction of both Ki-67 proliferation status and p53 mutations in PDAC with satisfactory diagnostic efficacy.

Objectives

To evaluate the safety, tolerability, and efficacy of ultrasound-guided percutaneous biopsy of penile masses.

Methods

A retrospective review of an institutional biopsy database was used to identify ultrasound-guided percutaneous biopsies of the penis performed between September 2004 and April 2025. Relevant clinical history, pre-biopsy imaging, biopsy technique, sedation plan, complications, final pathology, peri-procedural pain scores, and administered medications were recorded. Safety, tolerability, and efficacy of ultrasound-guided percutaneous biopsy of the penis were assessed.

Results

There were 15 patients who underwent 16 ultrasound-guided percutaneous penile mass biopsies. Procedures were performed as core-needle biopsies (CNB) using 18- or 20-gauge devices (n = 9), as fine needle aspiration (FNA) using 25-gauge needles (n = 5), or as a combination of 25-gauge FNA and 20-gauge CNB (n = 2). Most biopsies were performed using local anesthetic only (9/16, 56%), or local anesthetic in conjunction with moderate sedation (7/16, 44%). One patient received a dorsal penile nerve block in addition to moderate sedation. The procedures were well-tolerated, with only a single patient reporting periprocedural pain scores above 2. No major complications occurred. A single patient developed a small-to-moderate hematoma which was managed conservatively. Most cases yielded diagnostic tissue (14/16, 87.5%). In the two cases with nondiagnostic tissue, no malignancy was discovered on subsequent workup.

Conclusion

Ultrasound-guided percutaneous biopsy is a safe, well-tolerated, and efficacious procedure that should be considered a viable technique for sampling penile masses.