Comparing Radiomics features of tumour and healthy liver tissue in a limited CT dataset: A machine learning study

IntroductionLiver cancer lesions on Computed Tomography (CT) withholds a great amount of data, which is not visible to the radiologists and radiographer. Radiomics features can be extracted from the lesions and used to train Machine Learning (ML) algorithms to predict between tumour and liver tissue. The purpose of this study was to investigate and classify Radiomics features extracted from liver tumours and normal liver tissue in a limited CT dataset.MethodsThe Liver Tumour Segmentation Benchmark (LiTS) dataset consisting of 131 CT scans of the liver with segmentations of tumour tissue and healthy liver was used to extract Radiomic features. Extracted Radiomic features included size, shape, and location extracted with morphological and statistical techniques according to the International Symposium on Biomedical Imaging manual. Relevant features was selected with chi2 correlation and principal component analysis (PCA) with tumour and healthy liver tissue as outcome according to a consensus between three experienced radiologists. Logistic regression, random forest and support vector machine was used to train and validate the dataset with a 10-fold cross-validation method and the Grid Search as hyper-parameter tuning. Performance was evaluated with sensitivity, specificity and accuracy.ResultsThe performance of the ML algorithms achieved sensitivities, specificities and accuracy ranging from 96.30% (95% CI: 81.03%–99.91%) to 100.00% (95% CI: 86.77%–100.00%), 91.30% (95% CI: 71.96%–98.93%) to 100.00% (95% CI: 83.89%–100.00%)and 94.00% (95% CI: 83.45%–98.75%) to 100.00% (95% CI: 92.45%–100.00%), respectively.ConclusionML algorithms classifies Radiomics features extracted from healthy liver and tumour tissue with perfect accuracy. The Radiomics signature allows for a prognostic biomarker for hepatic tumour screening on liver CT.Implications for practiceDifferentiation between tumour and liver tissue with Radiomics ML algorithms have the potential to increase the diagnostic accuracy, assist in the decision-making of supplementary multiphasic enhanced medical imaging, as well as for developing novel prognostic biomarkers for liver cancer patients.     

Detection of metallic objects on digital radiographs with convolutional neural networks: A MRI screening tool

IntroductionScreening for metallic implants and foreign bodies before magnetic resonance imaging (MRI) examinations, are crucial for patient safety. History of health are supplied by the patient, a family member, screening of electronic health records or the picture and archive systems (PACS). PACS securely store and transmits digital radiographs (DR) and related reports with patient information. Convolutional neural networks (CNN) can be used to detect metallic objects in DRs stored in PACS. This study evaluates the accuracy of CNNs in the detection of metallic objects on DRs as an MRI screening tool.MethodsThe musculoskeletal radiographs (MURA) dataset consisting of 14.863 upper extremity studies were stratified into datasets with and without metal. For each anatomical region: Elbow, finger, hand, humerus, forearm, shoulder and wrist we trained and validated CNN algorithms to classify radiographs with and without metal. Algorithm performance was evaluated with area under the receiver-operating curve (AUC), sensitivity, specificity, predictive values and accuracies compared with a reference standard of manually labelling.ResultsSensitivities, specificities and area under the ROC-curves (AUC) for the six anatomic regions ranged from 85.33% (95% CI: 78.64%–90.57%) to 100.00% (95% CI: 98.16%–100.00%), 75.44% (95% CI: 62.24%–85.87%) to 93.57% (95% CI: 88.78%–96.75%) and 0.95 to 0.99, respectively.ConclusionCNN algorithms classify DRs with metallic objects for six different anatomic regions with near-perfect accuracy. The rapid and iterative capability of the algorithms allows for scalable expansion and as a substitute MRI screening tool for metallic objects.Implications for practiceAll CNNs would be able to assist in metal detection of digital radiographs prior to MRI, an substantially decrease screening time.     

Deep Learning Based on MR Imaging for Predicting Outcome of Uterine Fibroid Embolization

PurposeTo develop and validate a deep learning model based on routine magnetic resonance (MR) imaging obtained before uterine fibroid embolization to predict procedure outcome.Materials and MethodsClinical data were collected on patients treated with uterine fibroid embolization at the Hospital of the University of Pennsylvania from 2007 to 2018. Fibroids for each patient were manually segmented by an abdominal radiologist on a T1-weighted contrast-enhanced (T1C) sequence and a T2-weighted sequence of MR imaging obtained before and after embolization. A residual convolutional neural network (ResNet) model to predict clinical outcome was trained using MR imaging obtained before the procedure.ResultsInclusion criteria were met by 727 fibroids in 409 patients. At clinical follow-up, 85.6% (n = 350) of 409 patients (590 of 727 fibroids; 81.1%) experienced symptom resolution or improvement, and 14.4% (n = 59) of 409 patients (137 of 727 fibroids; 18.9%) had no improvement or worsening symptoms. The T1C trained model achieved a test accuracy of 0.847 (95% confidence interval [CI], 0.745–0.914), sensitivity of 0.932 (95% CI, 0.833–0.978), and specificity of 0.462 (95% CI, 0.232–0.709). In comparison, the average of 4 radiologists achieved a test accuracy of 0.722 (95% CI, 0.609–0.813), sensitivity of 0.852 (95% CI, 0.737–0.923), and specificity of 0.135 (95% CI, 0.021–0.415).ConclusionsThis study demonstrates that deep learning based on a ResNet model achieves good accuracy in predicting outcome of uterine fibroid embolization. If further validated, the model may help clinicians better identify patients who can most benefit from this therapy and aid clinical decision making.     

Applying patient characteristics,stent-graft selection,and pre-operative computed tomographic angiography data to a machine learning algorithm: Is endoleak prediction possible?

IntroductionThis study aims to predict endoleak after endovascular aneurysm repair (EVAR) using machine learning (ML) integration of patient characteristics, stent-graft configuration, and a selection of vessel lengths, diameters and angles measured using pre-operative computed tomography angiography (CTA).MethodsWe evaluated 1-year follow-up CT scans (arterial and delayed phases) in patients who underwent EVAR for the presence or absence of an endoleak. We also obtained data on the patient characteristics, stent-graft selection, and preoperative CT vessel morphology (diameter, length, and angle). The extreme gradient boosting (XGBoost) for the ML system was trained on 30 patients with endoleaks and 81 patients without. We evaluated 5217 items in 111 patients with abdominal aortic aneurysms, including the patient characteristics, stent-graft configuration and vascular morphology acquired using pre-EVAR abdominal CTA. We calculated the area under the curve (AUC) of our receiver operating characteristic analysis using the ML method.ResultsThe AUC, accuracy, 95% confidence interval (CI), sensitivity, and specificity were 0.88, 0.88, 0.79–0.97, 0.85, and 0.91 for ML applying XGBoost, respectively.ConclusionsThe diagnostic performance of the ML method was useful when factors such as the patient characteristics, stent-graft configuration and vessel length, diameter and angle of the vessels were considered from pre-EVAR CTA.Implications for practiceBased on our findings, we suggest that this is a potential application of ML for the interpretation of abdominal CTA scans in patients with abdominal aortic aneurysms scheduled for EVAR.     

Safety and Efficacy of Baseline Antiplatelet Treatment in Patients Undergoing Mechanical Thrombectomy for Ischemic Stroke: Antiplatelets Before Mechanical Thrombectomy

PurposeTo investigate the safety and efficacy of baseline antiplatelet treatment in patients with acute ischemic stroke (AIS) undergoing mechanical thrombectomy (MT).Materials and MethodsBaseline use of antiplatelet medication before MT for (AIS) may provide benefit on reperfusion and clinical outcome but could also carry an increased risk of intracranial hemorrhage (ICH). All consecutive patients with AIS and treated with MT with and without intravenous thrombolysis (IVT) between January 2012 and December 2019 in all centers performing MT nationwide were reviewed. Data were prospectively collected in national registries (eg, SITS-TBY and RES-Q). Primary outcome was functional independence (modified Rankin Scale 0–2) at 3 months; secondary outcome was ICH.ResultsOf the 4,351 patients who underwent MT, 1,750 (40%) and 666 (15%) were excluded owing to missing data from the functional independence and ICH outcome cohorts, respectively. In the functional independence cohort (n = 2,601), 771 (30%) patients received antiplatelets before MT. Favorable outcome did not differ in any antiplatelet, aspirin, and clopidogrel groups when compared with that in the no-antiplatelet group: odds ratio (OR), 1.00 (95% CI, 0.84–1.20); OR, 1.05 (95% CI, 0.86–1.27); and OR, 0.88 (95% CI, 0.55–1.41), respectively. In the ICH cohort (n = 3,685), 1095 (30%) patients received antiplatelets before MT. The rates of ICH did not increase in any treatment options (any antiplatelet, aspirin, clopidogrel, and dual antiplatelet groups) when compared with those in the no-antiplatelet group: OR, 1.03 (95% CI, 0.87–1.21); OR, 0.99 (95% CI, 0.83–1.18); OR, 1.10 (95% CI, 0.82–1.47); and OR, 1.43 (95% CI, 0.87–2.33), respectively.ConclusionsAntiplatelet monotherapy before MT did not improve functional independence or increase the risk of ICH.     

The Value of Preprocedural MR Imaging in Genicular Artery Embolization for Patients with Osteoarthritic Knee Pain

PurposeTo determine the value of preprocedural MR imaging in genicular artery embolization (GAE) for patients with osteoarthritic knee pain.Materials and MethodsThis single-center study retrospectively analyzed 28 knees in 18 patients who underwent GAE for intractable knee pain < 1 month after MR imaging. The pain experienced in each knee was evaluated on a 100-mm visual analog scale (VAS) at baseline and 1- and 3-month after GAE. “GAE responders” were defined as knees that exhibited greater than 30% reduction of VAS pain scores from baseline at both follow-up visits. Musculoskeletal radiologists evaluated MR images of the affected knee compartment regarding cartilage defects, osteophytes, subchondral cysts, bone marrow lesions (BMLs), meniscal injury, and joint effusion. The performances of Kellgren–Lawrence (KL) grading and MR findings in predicting GAE responders was estimated based on receiver operating characteristic curves.ResultsThe mean VAS pain score was 84.3 mm. BML (area under the curve [AUC], 0.860; P < .001), meniscal injury (AUC, 0.811; P = .003), and KL grading (AUC, 0.898; P < .001) were significantly associated with GAE outcome. To predict GAE responders, KL grade ≤ 2 yielded a sensitivity of 87.5% and a specificity of 60.9%, BML grade ≤ 1 yielded a sensitivity of 75.0% and a specificity of 69.6%, and meniscal injury grade ≤ 2 yielded a sensitivity of 83.3% and a specificity of 72.7%.ConclusionsLarge BMLs and severe meniscal injuries on MR imaging, as well as high KL grades, indicated poor responses to GAE.     

Diagnostic Performance of CT-Guided Bone Biopsies in Patients with Suspected Osteomyelitis of the Appendicular and Axial Skeleton with a Focus on Clinical and Technical Factors Associated with Positive Microbiology Culture Results

PurposeTo assess diagnostic performance of CT-guided percutaneous needle bone biopsy (CTNBB) in patients with suspected osteomyelitis and analyze whether certain clinical or technical factors were associated with positive microbiology results.Materials and MethodsAll CTNBBs performed in a single center for suspected osteomyelitis of the appendicular and axial skeleton during 2003–2018 were retrospectively reviewed. Specific inclusion criteria were clinical and radiologic suspicion of osteomyelitis. Standard of reference was defined using outcome of surgical histopathology and microbiology culture and clinical and imaging follow-up. Technical and clinical data (needle size, comorbidities, clinical factors, laboratory values, blood cultures) were collected. Logistic regression was performed to assess associations between technical and clinical data and microbiology biopsy outcome.ResultsA total of 142 CTNBBs were included (46.5% female patients; age ± SD 46.10 y ± 22.8), 72 (50.7%) from the appendicular skeleton and 70 (49.3%) from the axial skeleton. CTNBB showed a sensitivity of 42.5% (95% confidence interval [CI], 32.0%–53.6%) in isolating the causative pathogen. A higher rate of positive microbiology results was found in patients with intravenous drug use (odds ratio [OR] = 5.15; 95% CI, 1.2–21.0; P = .022) and elevated white blood cell count ≥ 10 × 10⁹/L (OR = 3.9; 95% CI, 1.62–9.53; P = .002). Fever (≥ 38°C) was another clinical factor associated with positive microbiology results (OR = 3.6; 95% CI, 1.3–9.6; P = .011).ConclusionsCTNBB had a low sensitivity of 42.5% for isolating the causative pathogen. Rate of positive microbiology samples was significantly higher in patients with IV drug use, elevated white blood cell count, and fever.     

Image-Guided Ablation of Recurrent or Unresectable Intrahepatic Cholangiocarcinoma

PurposeTo assess the safety and effectiveness of image-guided ablation of recurrent or unresectable intrahepatic cholangiocarcinoma (ICC).Materials and MethodsIn this retrospective study, 25 patients (14 women; age, 36–84 years) underwent 37 image-guided liver tumor ablation procedures to treat 47 ICCs (May 2004 to January 2022). At initial diagnosis, 20 patients had Stage 1 or 2 disease and 5 had Stage 3 or 4 disease. Before ablation, 19 (76.0%) of the 25 patients had progressed through prior treatments, including resection (n = 11), chemotherapy (n = 11), transarterial embolization (n = 3), or radiotherapy (n = 1); 6 (24.0%) of the 25 patients were treatment naïve. Ablation modality selection was based on patient and tumor characteristics and operator preference. Primary outcomes included local progression–free survival (LPFS) and overall survival (OS) after ablation. Statistical analysis included Kaplan-Meier (KM) survival analyses and Cox proportional hazards models.ResultsThe mean ablated tumor size was 2.0 cm ± 1.2 (range, 0.5–5.0 cm). The 1-, 2-, and 5-year LPFS rates were 84.0% (95% CI, 72.9–96.8), 73.0% (95% CI, 59.0–90.4), and 59.5% (95% CI, 41.6–85.1), respectively. The 1-, 2-, and 5-year secondary LPFS rates were 89.5% (95% CI, 80.2–99.9), 81.9% (95% CI, 69.4–96.6), and 75.6% (95% CI, 60.2–94.9). The 1-, 2-, and 5-year LPFS rates for tumors ≤2 cm in size were all 95.8% (95% CI, 88.2–100.0). The 1-, 2-, and 5-year OS rates were 78.5% (95% CI, 63.5–97.2), 68.4% (95% CI, 51.3–91.1), and 43.5% (95% CI, 23.5–80.5). Larger tumor size was associated with decreased time to local progression (hazard ratio, 1.93; P = .012).ConclusionsPercutaneous ablation provided favorable intermediate to long-term disease control for patients with recurrent or inoperable cholangiocarcinoma.     

Value of SPECT/CT in the diagnosis of avascular necrosis of the head of femur: A meta-analysis

IntroductionTo evaluate the diagnostic value of single photon emission computed tomography/computed tomography (SPECT/CT) in patients with avascular necrosis (AVN) of the femoral head.MethodsA search of the databases PubMed, ScienceDirect, and Google Scholar was undertaken using targeted index word. Studies satisfying inclusions and exclusions criteria were identified and additional related literature sources were considered. Analysis included pooled sensitivity and specificity, odds ratio (OR), and receiver operating characteristic (ROC) analysis.ResultsSeven studies were identified that specifically related to the diagnostic accuracy of SPECT/CT in the detection or characterisation of AVN of the femoral head. These were included in the meta-analysis. The pooled sensitivity and specificity were 94% (95% confidence interval of 87–97%) and 75% (95% confidence interval of 68–81%) respectively, the OR was 44.5 (with a 95% confidence interval of 18.2–108.6), and the area under the SROC was 93.73% (with a 95% confidence interval of 89.2%–98.3%).ConclusionThis meta-analysis provides strong evidence of the high diagnostic efficacy of SPECT/CT in the evaluation of AVN of the femoral head.Implications for practiceIn the absence of or contraindication to MRI, SPECT/CT is able to provide a suitable alternative for diagnosis of AVN of the head of femur.     

Safety and Effectiveness of Yttrium-90 Radioembolization around the Time of Immune Checkpoint Inhibitors for Unresectable Hepatic Metastases

PurposeTo assess the safety and effectiveness of yttrium-90 radioembolization and checkpoint inhibitor immunotherapy within a short interval for the treatment of unresectable hepatic metastases.Materials and MethodsThis single-institution retrospective study included 22 patients (12 men; median age, 65 y ± 11) with unresectable hepatic metastases and preserved functional status (Eastern Cooperative Oncology Group performance status 0/1) who received immunotherapy and radioembolization within a 15-month period (median, 63.5 d; interquartile range, 19.7–178.2 d) from February 2013 to March 2018. Primary malignancies were uveal melanoma (12 of 22; 54.5%), soft tissue sarcoma (3; 13.6%), cutaneous melanoma (3; 14%), and others (4; 18.2%). Studies were reviewed to March 2019 to assess Common Terminology Criteria for Adverse Events grade 3/4 toxicities, disease progression, and death.ResultsThere were no grade 4 toxicities within 6 mo of radioembolization. Grade 3 hepatobiliary toxicities occurred in 3 patients (13.6%) within 6 months, 2 from rapid disease progression and 1 from a biliary stricture. Two patients (9.1%) experienced clinical toxicities, including grade 4 colitis at 6 months and hepatic abscess at 3 months. Median overall survival (OS) from first radioembolization was 20 mo (95% confidence interval [CI], 12.5–27.5 mo), and median OS from first immunotherapy was 23 months (95% CI, 15.9–30.1 mo). Within the uveal melanoma subgroup, the median OS from first radioembolization was 17.0 months (95% CI, 14.2–19.8 mo). Median time to progression was 7.8 months (95% CI, 3.3–12.2 mo), and median progression-free survival was 7.8 mo (95% CI, 3.1–12.4 mo).ConclusionsCheckpoint immunotherapy around the time of radioembolization is safe, with a low incidence of toxicity independent of primary malignancy.     

Yttrium-90 Radiation Segmentectomy in Oligometastatic Secondary Hepatic Malignancies

PurposeTo evaluate the safety and efficacy of yttrium-90 (⁹⁰Y) radiation segmentectomy (RS) in the treatment of oligometastatic secondary hepatic malignancies.Materials and MethodsThis institutional review board–approved retrospective study evaluated 16 patients with oligometastatic secondary hepatic malignancies who were treated with RS. The median patient age was 61.9 years (range, 38.6–85.7 years). Of the 16 patients, 11 (68.8%) presented with solitary lesions. The median index tumor size was 3.1 cm (95% CI, 2.3–3.9). Primary outcomes were evaluation of clinical and biochemical toxicities using National Cancer Institute Common Terminology Criteria for Adverse Events, version 5.0, and imaging response using Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary outcomes were time to progression (TTP) and overall survival (OS) as estimated by the Kaplan-Meier method.ResultsClinical Grade 3 toxicities were limited to 1 (6.7%) patient who experienced fatigue, abdominal pain, nausea, and vomiting. Biochemical Grade 3 toxicities occurred in 1 (6.7%) patient who experienced lymphopenia. No Grade 4 clinical or biochemical toxicities were identified. Disease control was achieved in 14 (93.3%) of 15 patients. The median TTP of the treated tumor was 72.9 months (95% CI, 11.2 to no estimate). The median OS was 60.9 months (95% CI, 24.7 to no estimate).Conclusions⁹⁰Y RS displayed an excellent safety profile and was effective in achieving a high disease control rate in the treatment of oligometastatic secondary hepatic malignancies.     

Safety and Effectiveness of Advanced Retrieval Techniques for Inferior Vena Cava Filters Compared with Standard Retrieval Techniques: A Systematic Review of the Literature and Meta-Analysis

PurposeTo investigate the pooled safety and effectiveness of advanced retrieval techniques for inferior vena cava (IVC) filters compared with standard retrieval techniques through a systematic review of the literature and meta-analysis.Materials and MethodsA systematic search of retrievable IVC filters between 1980 and 2020 was conducted. Studies were included if both standard and advanced retrieval techniques were utilized in the same cohort, retrieval success rates and adverse event rates were described for each technique, and advanced techniques were employed after the failure of standard techniques. Study heterogeneity was assessed by the I² statistic. The outcomes included retrieval success rates and adverse event rates for standard and advanced retrieval techniques.ResultsOf 1,631 articles, 21 (1%) studies met inclusion criteria. The study heterogeneity was high with an I² of 98%. The pooled random-effects outcomes included an overall standard retrieval success rate of 76% (95% confidence interval [CI], 65%–84%), with minor and major adverse event rates of 1% (95% CI, 0%–1%) and 1% (95% CI, 0%–1%), respectively. The overall pooled advanced retrieval success rates were 90% (95% CI, 82%–94%), with minor and major adverse event rates of 5% (95% CI, 2%–9%) and 4% (95% CI, 2%–6%), respectively. The standard retrievals were 16% less likely (risk ratio) to be successful (95% CI, 32% less likely to 4% more likely; P = .11). The major and minor adverse event rates were 88% and 84% less likely in standard retrievals compared with advanced retrievals, respectively (95% CI, 86%–94%; P < .0001; 95% CI, 70%–91%; P < .0001).ConclusionsAdvanced retrieval techniques for IVC filters permit a higher retrieval success rate with low adverse event rates in cases of standard retrieval failure.     

Predictors for Nonhome Patient Discharge following Lower Extremity Arterial Interventions

PurposeTo identify the variables associated with patient discharge disposition to optimize postprocedural care and discharge planning following lower extremity arterial interventions for peripheral artery disease (PAD).Materials and MethodsThe 2014–2017 American College of Surgeons National Surgical Quality Improvement Program database was queried using current procedural terminology codes for endovascular infrainguinal interventions for PAD. The main outcome variable of interest was nonhome discharge. Covariates included patient sociodemographic variables, age quartile (upper quartile, ≥77 years), comorbidities (diabetes, renal disease, bleeding disorder, congestive heart failure [CHF], and chronic obstructive pulmonary disease), presence of an open wound before a procedure, type of procedure, operative time, symptom severity, American Society of Anesthesiologists class, and baseline functional status. Univariate analysis and multivariate logistic regression were performed on Stata/SE 15.1.ResultsA total of 3,190 patients met the inclusion criteria, of whom 664 (20.8%) had nonhome discharge. Multivariate regression revealed that age (odds ratio [OR], 1.9 for the upper age quartile [>77 years]; 95% confidence interval [CI], 1.46–2.50), operative time (OR, 1.2 per increase in quartile; 95% CI, 1.09–1.30), preoperative wound (OR, 1.5; 95% CI, 1.24–1.90), renal failure (OR, 1.7; 95% CI, 1.30–2.14), CHF (OR, 2.2; 95% CI, 1.51–3.24), symptom severity (OR, 1.7; 95% CI, 1.46–1.98), and independent functional status (OR, 0.74; 95% CI, 0.59–0.92; P = .007) were associated with nonhome discharge. All P values were ≤.001 unless otherwise stated.ConclusionsProlonged procedural time, the presence of preprocedural wound and patient comorbidities, symptomatology, and baseline functional status may be used to identify patients who will require a nonhome discharge and early discharge planning.     

Clinical Utility of Transient Elastography in the Management of Patients with Budd-Chiari Syndrome Undergoing Endovascular Intervention

PurposeTo quantify liver stiffness measurement (LSM) changes after endovascular intervention for Budd-Chiari syndrome (BCS) and evaluate whether LSM changes predict restenosis after endovascular intervention.Materials and MethodsPatients with BCS who underwent endovascular intervention and had at least 2 LSM values available after the intervention were included. ΔLSM was the difference between LSMs estimated at the last and second last hospital visits. In patients with restenosis, 2 LSM values before restenosis were included. ΔLSM% was calculated as the ratio of ΔLSM to the LSM at the second last visit and expressed as a percentage. Odds ratio (OR) with confidence interval (CI) and area under the receiver operating characteristic curves (AUROCs) were calculated for the predictors of restenosis.ResultsThe median baseline and postinterventional 1-week, 3-month, 6-month, and 12-month LSM values were 47.2 kPa (33.8–68.4 kPa), 29.2 kPa (24.5–43.0 kPa), 26.2 kPa (18.6–38.9 kPa), 20.9 kPa (13.3–29.8 kPa), and 17.3 kPa (11.8–25.4 kPa), respectively. Of the 118 patients, including 67 men, restenosis developed in 10 patients after a median (interquartile range) duration of 19 months (11–46 months). ΔLSM% was higher (more positive) in patients with restenosis than in those without restenosis (44.7 [8.3–134.3] vs ?6.6 [?19.4 to 14.9], P = .001). ΔLSM% was a significant predictor of restenosis with an OR of 1.032 (95% CI, 1.015–1.050; P < .001). The AUROC for ΔLSM% was 0.831 (95% CI, 0.750–0.893; P = .001), and a ΔLSM% increment of 13.2% predicted restenosis with a sensitivity and specificity of 80.0% and 74.1%, respectively.ConclusionsLSM gradually decreases after endovascular intervention, and transient elastography is a promising test for detecting restenosis after the endovascular treatment of patients with BCS.     

Safety and Efficacy of Percutaneous Translumbar Inferior Vena Cava Catheters: A Systematic Review and Meta-Analysis

PurposeTo examine the reported adverse events associated with inferior vena cava (IVC) catheterization and investigate the reasons for discrepancies between reports.Materials and MethodsCochrane Library trials register, PubMed, Embase, and Scopus databases were systematically searched for studies that included any terms of IVC and phrases related to catheters or central access. Of the 5,075 searched studies, 137 were included in the full-text evaluation. Of these, 37 studies were included in the systematic review, and the adverse events reported in 16 of these 37 identified studies were analyzed. An inverse-variance random-effects model was used to conduct the meta-analysis. Outcomes were summarized by the incidence rate (IR) and 95% CI.ResultsCompared with that of catheters <10 F in size (IR, 0.08; 95% CI, 0.03–0.12), the incidence of catheter-related infections per 100 catheter days was 0.2 more for catheters ≥10 F in size (IR, 0.28; 95% CI, 0.25–0.31). In addition, dual-lumen catheters showed 0.13 more malfunction per 100 catheter days (IR, 0.27; 95% CI, 0.16–0.37) than that shown by single-lumen catheters (IR, 0.14; 95% CI, 0.09–0.19). Both differences were statistically significant. Other adverse events were malposition (IR, 0.04; 95% CI, 0.04–0.05), fracture (IR, 0.01; 95% CI, 0.00–0.02), kinking (IR, 0.01; 95% CI, 0.00–0.01), replaced catheter (IR, 0.2; 95% CI, 0.1–0.31), removal (IR, 0.13; 95% CI, 0.1–0.16), IVC thrombosis (IR, 0.01; 95% CI, 0.00–0.03), and retroperitoneal hematoma (IR, 0.01; 95% CI, 0.00–0.01), all per 100 catheter days.ConclusionsTranslumbar IVC access is an option for patients with exhausted central veins. Small-caliber catheters cause fewer catheter-related infections, and single-lumen catheters function longer.     

Stereotactic Body Radiotherapy for Stage I Renal Cell Carcinoma: National Treatment Trends and Outcomes Compared to Partial Nephrectomy and Thermal Ablation

PurposeTo assess use of stereotactic body radiotherapy (SBRT) for stage I renal cell carcinoma (RCC) and compare outcomes with thermal ablation and partial nephrectomy (PN).Materials and MethodsThe 2004–2015 National Cancer Database was investigated for histopathologically proven stage I RCC treated with PN, cryoablation, radiofrequency (RF) or microwave (MW) ablation, or SBRT. Patients were propensity score–matched to account for potential confounders, including patient age, sex, race, comorbidities, tumor size, histology, grade, tumor sequence, administration of systemic therapy, treatment in academic vs nonacademic centers, treatment location, and year of diagnosis. Overall survival (OS) was evaluated with Kaplan-Meier plots, log-rank tests, and Cox proportional hazards models.ResultsA total of 91,965 patients were identified (SBRT, n = 174; PN, n = 82,913; cryoablation, n = 5,446; RF/MW ablation, n = 3,432). Stage I patients who received SBRT tended to be older women with few comorbidities treated at nonacademic centers in New England states. After propensity score matching, a cohort of 636 patients was obtained with well-balanced confounders between treatment groups. In the matched cohort, OS after SBRT was inferior to OS after PN and thermal ablation (PN vs SBRT, hazard ratio [HR] = 0.29, 95% confidence interval [CI] 0.19–0.46, P < .001; cryoablation vs SBRT, HR = 0.40, 95% CI 0.26–0.60, P < .001; RF/MW ablation vs SBRT, HR = 0.46, 95% CI 0.31–0.67, P < .001). Compared with PN, neither cryoablation nor RF/MW ablation showed significant difference in OS (cryoablation vs PN, HR = 1.35, 95% CI 0.80–2.28, P = .258; RF/MW ablation vs PN, HR = 0.64, 95% CI 0.95–2.55, P = .079).ConclusionsCurrent SBRT protocols show lower OS compared with thermal ablation and PN, whereas thermal ablation and PN demonstrate comparable outcomes.     

Comparison between Antegrade versus Retrograde Ureteral Stent Placement for Malignant Ureteral Obstruction

PurposeTo compare the technical success of antegrade uteral stent (AUS) and retrograde ureteral stent (RUS) placements in patients with malignant ureteral obstruction (MUO) and to determine the predictors of technical failure of RUS.Materials and MethodsThis study retrospectively included 61 AUS placements (44 patients) performed under fluoroscopic guidance and 76 RUS placements (55 patients) performed under cystoscopic guidance in patients with MUO from January 2019 to December 2020. Technical success rates of the 2 techniques were compared using inverse probability of treatment weighting (IPTW) analysis. Logistic regression was used to identify predictive factors for technical failures.ResultsTechnical success was achieved in 98.4% of the AUS group and 47.4% of the RUS group. After stabilized IPTW, the technical success rate was higher in the AUS group than in the RUS group (adjusted risk difference, 49.4%; 95% confidence interval [CI], 35.4%–63.1%). The independent predictors for technical failure of the RUS procedure were age of ≥65 years (odds ratio [OR], 5.56; 95% CI, 1.73–21.27), ureteral orifice invasion (OR, 4.21; 95% CI, 1.46–13.46), and extrinsic cancer (OR, 15.58; 95% CI, 2.92–111.81).ConclusionsThe technical success rate of AUS placement was higher than that of RUS placement in patients with MUO. RUS failure was associated with age of ≥65 years, cancer with ureteral orifice invasion, and extrinsic ureteral obstruction.