Non-inferiority, randomised, open-label clinical trial on the effectiveness of transurethral microwave thermotherapy compared to prostatic artery embolisation in reducing severe lower urinary tract symptoms in men with benign prostatic hyperplasia: study protocol for the TUMT-PAE-1 trial.

BACKGROUND: One-fourth of men older than 70 years have lower urinary tract symptoms (LUTS) that impair their quality of life. Transurethral resection of the prostate (TURP) is considered the gold standard for surgical treatment of LUTS caused by benign prostatic hyperplasia (BPH) that cannot be managed conservatively or pharmacologically. However, TURP is only an option for patients fit for surgery and can result in complications. Transurethral microwave thermotherapy (TUMT) and prostatic artery embolisation (PAE) are alternative minimally invasive surgical therapies (MISTs) performed in an outpatient setting. Both treatments have shown to reduce LUTS with a similar post-procedure outcome in mean International Prostate Symptom Score (IPSS). It is however still unknown if TUMT and PAE perform equally well as they have never been directly compared in a randomised clinical trial. The objective of this clinical trial is to assess if PAE is non-inferior to TUMT in reducing LUTS secondary to BPH. METHODS: This study is designed as a multicentre, non-inferiority, open-label randomised clinical trial. Patients will be randomised with a 1:1 allocation ratio between treatments. The primary outcome is the IPSS of the two arms after 6 months. The primary outcome will be evaluated using a 95% confidence interval against the predefined non-inferiority margin of + 3 points in IPSS. Secondary objectives include the comparison of patient-reported and functional outcomes at short- and long-term follow-up. We will follow the patients for 5 years to track long-term effect. Assuming a difference in mean IPSS after treatment of 1 point with an SD of 5 and a non-inferiority margin set at the threshold for a clinically non-meaningful difference of + 3 points, the calculated sample size was 100 patients per arm. To compensate for 10% dropout, the study will include 223 patients. DISCUSSION: In this first randomised clinical trial to compare two MISTs, we expect non-inferiority of PAE to TUMT. The most prominent problems with MIST BPH treatments are the unknown long-term effect and the lack of proper selection of candidates for a specific procedure. With analysis of the secondary outcomes, we aspire to contribute to a better understanding of durability and provide knowledge to guide treatment decisions. TRIAL REGISTRATION: ClinicalTrials.gov NCT05686525. Registered on January 17, 2023, https://clinicaltrials.gov/study/NCT05686525 .

Transarterial Embolization of Geniculate Arteries Reduces Pain and Improves Physical Function in Knee Osteoarthritis-A Prospective Cohort Study.

Knee osteoarthritis (OA) affects millions worldwide, leading to pain and reduced quality of life. Conventional treatments often fail to provide adequate relief, necessitating new therapeutic approaches. This study evaluated the efficacy and safety of genicular artery embolization (GAE) using permanent microspheres in patients with mild-to-moderate knee OA. In this prospective, single-center study, 17 participants underwent GAE. KOOS (Knee injury and Osteoarthritis Outcome Score), WOMAC (The Western Ontario and McMaster Universities Arthritis Index), and IPAQ (International Physical Activity Questionnaire) scores, along with physical performance tests, medication use, and dual-energy X-ray absorptiometry (DEXA) scans, were assessed at baseline and at multiple follow-up points over six months. The primary endpoint, VAS at six months, showed significant improvement (median reduction from 66 mm to 40 mm, p = 0.0004). All pain and function scores, as well as physical performance tests, improved significantly. No clinically relevant changes in medication use or DEXA parameters were observed after six months. Only minor, self-limiting adverse events occurred. This study indicates that GAE is a promising minimally invasive treatment for knee OA, providing significant pain relief and functional improvement. However, further long-term, randomized trials are needed to confirm these findings and establish optimal patient selection criteria.

Copenhagen Mesenteric stent study (COMESS)-a randomized trial of stent versus covered stent treatment for chronic mesenteric ischemia.

BACKGROUND: Current management of mesenteric ischemia is primarily endovascular stent treatment. Typical CMI symptoms are postprandial abdominal pain, food fear, weight loss, and diarrhea. Revascularization is often necessary, as mesenteric ischemia may progress to bowel necrosis and death if left untreated. This study aims to compare the outcome using bare metal stent (BMS) or covered stent (CS) in the endovascular treatment of chronic and acute on chronic mesenteric ischemia. METHODS: This is an investigator-driven, prospective, randomized, single-blinded, and single-center, national cohort study at the Copenhagen University Hospital, Denmark. A total of 98 patients with chronic mesenteric ischemia (CMI) and acute-on-chronic mesenteric ischemia (AoCMI) will be randomized to treatment with either BeSmooth BMS (Bentley Innomed GmbH) or BeGraft CS (Bentley Innomed GmbH). Randomization occurs intraoperatively after lesion crossing. DISCUSSION: There is currently no published data from prospective controlled trials regarding the preferred type of stent used for the treatment of chronic and acute-on-chronic mesenteric ischemia. This trial will evaluate the short- and long-term outcome of BMS versus CS when treating CMI and AoCMI, as well as the benefit of a more intense postoperative surveillance program. TRIAL REGISTRATION: ClinicalTrials.gov NCT05244629. Registered on February 8, 2022.

Efficacy of High-Dose Dexamethasone in Reducing the Symptoms of Postembolization Syndrome Following Prostatic Artery Embolization: Results of a Double-Blind Randomized Controlled Trial.

PURPOSE: To evaluate the efficacy of a single perioperative dose of dexamethasone in reducing postembolization syndrome following prostatic artery embolization. MATERIALS AND METHODS: We conducted a single-center double-blind randomized controlled trial from March 2021 to May 2022 (NCT04588857). Participants were randomized to receive either i.v. 24 mg dexamethasone or saline. The primary outcome measures were temperature, pain, and quality of life in the first 5 days following prostatic artery embolization. Sample size of 60 patients was needed for the assessment of primary outcomes. Participants were followed for 6 months and assessed for a variety of secondary outcome measures including inflammatory markers and lower urinary tract symptoms severity. RESULTS: Due to lack of clinical effect and mild symptoms in the control group, the trial was terminated early. 31 participants (16 dexamethasone vs. 15 control) were enrolled and analyzed. A difference in mean temperature was observed on day 1 (37.23 ± 0.64 °C control vs 36.74 ± 0.41 °C dexamethasone, p = 0.02, 95% CI 0.09-0.89). Difference in pain (score out of 10) was seen only on day 5 (1.48 ± 1.2 control vs. 2.9 ± 2.24 dexamethasone, p = 0.04, 95% CI - 2.78-- 0.04). A difference in C-reactive protein values was observed on day 2 (108 [54-161] mg/l control vs 10 [5-33] mg/l dexamethasone, p < 0.01). No significant differences in other outcomes were observed. No side effects were recorded. CONCLUSIONS: Twenty-four milligrams of dexamethasone bolus is safe but does not reduce postembolization syndrome following prostatic artery embolization.

Iodine density mapping for the diagnosis of acute bowel ischemia using fast kV-switching dual-energy CT.

PURPOSE: To evaluate the diagnostic capabilities of a supplementary color ramped iodine density map compared to virtual monoenergetic images (VMIs) at 74 keV in the diagnosis of acute bowel ischemia (ABI). METHODS: Data for this study were prospectively gathered and retrospectively evaluated. Patients referred to the Department of Diagnostic Radiology between October 2020 and August 2022 on the suspicion of ABI and underwent surgery < 12 h following fast kV-switching venous phase abdominal dual-energy CT (DECT) were consecutively included. Images were evaluated by two board-certified radiologists and two radiology residents. First round included only 74 keV VMIs resembling conventional 120 kVp images, and the second round included a supplementary iodine density map. Readers were asked to register presence of ABI as well as their confidence in their diagnosis based on a 5-point Likert scale. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for each observer with the surgical findings as the gold-standard. McNemar's and Wilcoxon signed-rank test were used to compare registrations and diagnostic confidence across assessment rounds. RESULTS: A total of 29 patients resulting in 31 DECT scans were included. Fourteen cases of ischemic/necrotic bowel were reported following surgery. Sensitivity and NPV were decreased with the use of supplementary iodine map images compared to 120 kVp-like images without supplementary iodine map images for three of four observers (round 1 range: 71.4-92.9% and 78.0-94.8%; round 2 range: 57.1-78.6% and 70.1-83.3%, respectively), while specificity and PPV were increased for three of four observers (round 1 range: 64.7-94.1% and 67.4-93.1%; round 2 range: 88.2-94.1% and 73.8-91.1%, respectively). However, no significant difference in ABI diagnosis or diagnostic confidence was found (p-value range: 0.07-1.00 and 0.23-0.58, respectively). CONCLUSION: No significant difference for the diagnosis of ABI was found using supplementary iodine mapping. Our study may suggest a trend of increased specificity and decreased sensitivity, hence, the use of supplementary iodine mapping should be carefully considered.

Cutaneous vascular calcifications in patients with chronic kidney disease and calcific uremic arteriolopathy: a cross-sectional study.

INTRODUCTION: Calcific uremic arteriolopathy is a life-threatening cutaneous condition in patients with chronic kidney disease. Often, clinical diagnosis is accompanied by histopathologic evaluations demonstrating vascular calcium deposits. We aimed to investigate the presence of cutaneous calcifications in non-lesional tissue in patients with chronic kidney disease, and the relation to systemic vascular calcification. METHODS: We investigated the presence of cutaneous vascular calcifications in non-lesional skin biopsies from patients with current or previous calcific uremic arteriolopathy and patients with different stages of chronic kidney disease without calcific uremic arteriolopathy, and explored their association with vascular calcification in other vascular beds. Systemic vascular calcification was examined by mammography and lumbar X-ray. RESULTS: Thirty-nine adults were enrolled (current or previous calcific uremic arteriolopathy, n = 9; end-stage chronic kidney disease, n = 12; chronic kidney disease stage 3b-4, n = 12; healthy controls, n = 6). All calcific uremic arteriolopathy patients had end-stage kidney disease. Cutaneous vascular calcifications were not present in any of the non-lesional skin punch biopsies. Breast arterial calcification was demonstrated in patients with calcific uremic arteriolopathy (75%) and chronic kidney disease (end-stage 67% and stage 3b-4 25%, respectively), but in none of the controls. All chronic kidney disease patients had systemic calcification on lumbar X-ray (median score 21, 22, and 15 in patients with calcific uremic arteriolopathy, end-stage kidney disease and chronic kidney disease stage 3b-4). The serum calcification propensity was significantly different between groups. DISCUSSION: Despite a high burden of systemic vascular calcification, cutaneous calcium deposits in non-lesional tissue could not be demonstrated histopathologically in patients with chronic kidney disease (with or without current or previous calcific uremic arteriolopathy). Further studies to determine whether these findings are representative or attributed to other factors are warranted.

Learning insertion of a Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA) catheter: Is clinical experience necessary? A prospective trial.

BACKGROUND: Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an emerging and potentially life-saving procedure, necessitating qualified operators in an increasing number of centres. The procedure shares technical elements with other vascular access procedures using the Seldinger technique, which is mastered by doctors not only in endovascular specialties but also in trauma surgery, emergency medicine, and anaesthesiology. We hypothesised that doctors mastering the Seldinger technique (experienced anaesthesiologist) would learn the technical aspects of REBOA with limited training and remain technically superior to doctors unfamiliar with the Seldinger technique (novice residents) given similar training. METHODS: This was a prospective trial of an educational intervention. Three groups of doctors were enroled: novice residents, experienced anaesthesiologists, and endovascular experts. The novices and the anaesthesiologists completed 2.5 h of simulation-based REBOA training. Their skills were tested before and 8-12 weeks after training using a standardised simulated scenario. The endovascular experts, constituting a reference group, were equivalently tested. All performances were video recorded and rated by three blinded experts using a validated assessment tool for REBOA (REBOA-RATE). Performances were compared between groups and with a previously published pass/fail cutoff. RESULTS: Sixteen novices, 13 board-certified specialists in anaesthesiology, and 13 endovascular experts participated. Before training, the anaesthesiologists outperformed the novices by 30 percentage points of the maximum REBOA-RATE score (56% (SD 14.0) vs 26% (SD 17%), p<0.01). After training, there was no difference in skills between the two groups (78% (SD 11%) vs 78 (SD 14%), p = 0.93). Neither group reached the endovascular experts' skill level (89% (SD 7%), p<0.05). CONCLUSION: For doctors mastering the Seldinger technique, there was an initial inter-procedural transfer of skills advantage when performing REBOA. However, after identical simulation-based training, novices performed equally well to anaesthesiologists, indicating that vascular access experience is not a prerequisite to learning the technical aspects of REBOA. Both groups would need more training to reach technical proficiency.

Evaluation of thin-slice abdominal DECT using deep-learning image reconstruction in 74 keV virtual monoenergetic images: an image quality comparison.

PURPOSE: To compare noise, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR) and image quality using deep-learning image reconstruction (DLIR) vs. adaptive statistical iterative reconstruction (ASIR-V) in 0.625 and 2.5 mm slice thickness gray scale 74 keV virtual monoenergetic (VM) abdominal dual-energy CT (DECT). METHODS: This retrospective study was approved by the institutional review board and regional ethics committee. We analysed 30 portal-venous phase abdominal fast kV-switching DECT (80/140kVp) scans. Data were reconstructed to ASIR-V 60% and DLIR-High at 74 keV in 0.625 and 2.5 mm slice thickness. Quantitative HU and noise assessment were measured within liver, aorta, adipose tissue and muscle. Two board-certified radiologists evaluated image noise, sharpness, texture and overall quality based on a five-point Likert scale. RESULTS: DLIR significantly reduced image noise and increased CNR as well as SNR compared to ASIR-V, when slice thickness was maintained (p < 0.001). Slightly higher noise of 5.5-16.2% was measured (p < 0.01) in liver, aorta and muscle tissue at 0.625 mm DLIR compared to 2.5 mm ASIR-V, while noise in adipose tissue was 4.3% lower with 0.625 mm DLIR compared to 2.5 mm ASIR-V (p = 0.08). Qualitative assessments demonstrated significantly improved image quality for DLIR particularly in 0.625 mm images. CONCLUSIONS: DLIR significantly reduced image noise, increased CNR and SNR and improved image quality in 0.625 mm slice images, when compared to ASIR-V. DLIR may facilitate thinner image slice reconstructions for routine contrast-enhanced abdominal DECT.

Focus on Radiation Protection Improves Both Correct Behavior and Procedural Performance During Simulation-Based Training - A Randomized Comparison.

BACKGROUND: To explore whether simulation-based endovascular training with focus on radiation safety could improve correct behavior without jeopardizing the learning of procedural skills. METHODS: Twenty-four residents without previous endovascular experience completed 10 clinical scenarios on a virtual-reality endovascular simulator with software for peripheral endovascular interventions. Participants were randomized to receive feedback (n = 12) or not (n = 12) on radiation protection (RP) performance after each case. Expert assessments were done at the first, second, fourth, seventh, and 10th case on RP and endovascular skills (ES). Automatic simulator metrics on procedure time, contrast dose, handling errors, and estimated radiation exposure to patient and operator were registered. Outcome metrics were analyzed by two-way mixed analysis of variance pairwise comparisons with independent t-tests. Correlations were explored using Pearson's r for internal consistency reliability. RESULTS: The RP performance was similar in both groups at their first attempt (P = 0.61), but the feedback group significantly outperformed the control group over time (P < 0.001 for all comparisons). The feedback group was however slower to learn the ES at start (P = 0.047 at second performance), but after 7 attempts no difference was shown (P = 0.59). The feedback group used more time (19.5 vs. 15.3 min; P = 0.007) but less contrast (60 vs. 100 mL; P < 0.001). The number of errors was the same in both groups, but all metrics regarding radiation exposure favored the feedback group (P-values from 0.001 to 0.008). CONCLUSIONS: Simulation-based training (SBT) is effective to acquire basic endovascular intervention skills and concurrently learn RP behavior when feedback on radiation culture is provided.

Characterizing incidental mass lesions in abdominal dual-energy CT compared to conventional contrast-enhanced CT.

BACKGROUND: Incidental findings are common in abdominal computed tomography (CT) and often warrant further investigations with economic implications as well as implications for patients. PURPOSE: To evaluate the potential of dual-energy CT (DECT) in the identification and/or characterization of abdominal incidental mass lesions compared to conventional contrast-enhanced CT. MATERIAL AND METHODS: This retrospective study from a major tertiary hospital included 96 patients, who underwent contrast-enhanced abdominal DECT. Incidental lesions in adrenals, kidneys, liver, and pancreas were evaluated by two board-certified abdominal radiologists. Observer 1 only had access to standard CT reconstructions, while observer 2 had access to standard CT as well as DECT reconstructions. Disagreements were resolved by consensus review and used as a reference for observers using McNemar's test. RESULTS: Observers 1 and 2 identified a total of 40 and 34 findings, respectively. Furthermore, observer 1 registered 13 lesions requiring follow-up, of which seven (two renal and five adrenal lesions) were resolved following consensus review using DECT (P = 0.008). The inter-observer agreement was near perfect (κ = 0.82). CONCLUSION: DECT has the potential to improve the immediate characterization of incidental findings when compared to conventional CT for abdominal imaging.

Quantitative and qualitative assessments of deep learning image reconstruction in low-keV virtual monoenergetic dual-energy CT.

OBJECTIVES: To evaluate a novel deep learning image reconstruction (DLIR) technique for dual-energy CT (DECT) derived virtual monoenergetic (VM) images compared to adaptive statistical iterative reconstruction (ASIR-V) in low kiloelectron volt (keV) images. METHODS: We analyzed 30 venous phase acute abdominal DECT (80/140 kVp) scans. Data were reconstructed to ASIR-V and DLIR-High at four different keV levels (40, 50, 74, and 100) with 1- and 3-mm slice thickness. Quantitative Hounsfield unit (HU) and noise assessment were measured within the liver, aorta, fat, and muscle. Subjective assessment of image noise, sharpness, texture, and overall quality was performed by two board-certified radiologists. RESULTS: DLIR reduced image noise by 19.9-35.5% (p < 0.001) compared to ASIR-V in all reconstructions at identical keV levels. Contrast-to-noise ratio (CNR) increased by 49.2-53.2% (p < 0.001) in DLIR 40-keV images compared to ASIR-V 50 keV, while no significant difference in noise was identified except for 1 and 3 mm in aorta and for 1-mm liver measurements, where ASIR-V 50 keV showed 5.5-6.8% (p < 0.002) lower noise levels. Qualitative assessment demonstrated significant improvement particularly in 1-mm reconstructions (p < 0.001). Lastly, DLIR 40 keV demonstrated comparable or improved image quality ratings when compared to ASIR-V 50 keV (p < 0.001 to 0.22). CONCLUSION: DLIR significantly reduced image noise compared to ASIR-V. Qualitative assessment showed that DLIR significantly improved image quality particularly in thin sliced images. DLIR may facilitate 40 keV as a new standard for routine low-keV VM reconstruction in contrast-enhanced abdominal DECT. KEY POINTS: • DLIR enables 40 keV as the routine low-keV VM reconstruction. • DLIR significantly reduced image noise compared to ASIR-V, across a wide range of keV levels in VM DECT images. • In low-keV VM reconstructions, improvements in image quality using DLIR were most evident and consistent in 1-mm sliced images.

Selective arterial embolization of renal angiomyolipomas: A 10-year experience.

Objectives: To study safety and efficacy of selective endovascular trans-arterial embolization (TAE) of renal angiomyolipoma (AML) in a 10-year period at a regional tertiary referral center in Denmark. Patients and methods: All 56 patients who underwent TAE of renal AML at Departments of Urology and Radiology, Copenhagen University Hospital - Rigshospitalet, Denmark, from 2009 to 2020 were included. Seven without preoperative and postoperative imaging were excluded, leaving 49 patients for analysis. From national electronic medical records, we retrieved patient characteristics, surgical data, and follow-up data. Tumor size at the time of embolization and during follow-up was compared using Student's paired t test. Estimated glomerular filtration rate (eGFR) pre- and post-embolization were compared using Wilcoxon rank sum test. Results: We included 49 patients of whom 4 had two tumors treated in the same TAE procedure. Median age was 50 years (interquartile range [IQR]: [29-67 years]), and the median follow-up time was 4.6 years [IQR: 3.0-6.7 years]. Post-embolization syndrome (PES) was experienced in 27 patients, and non-PES in 5 patients. Median length of hospital stay was 0 days [IQR, 0-1]. Postoperative Everolimus immunosuppressive treatment was offered to seven patients. Median tumor size was 6.0 cm [IQR: 4.6-7.9 cm] and was significantly reduced to 3.7 cm [IQR: 2.5-5.2 cm] after treatment (p < 0.001). Kidney function was not affected by TAE. Three deaths, not related to AML, were noted during follow-up. Conclusion: Embolization of AML was in this cohort effective to significantly reduce tumor size without serious adverse events and loss of renal function. TAE is a safe and efficacious treatment and the preferred minimally invasive treatment option of AML.

Prostatic artery embolization in men with severe hemophilia a: a case report of two patients.

BACKGROUND: This is the first case report describing the peri- and postoperative hemostasis plans in two men with severe hemophilia A (HA) who underwent prostatic artery embolization (PAE) for symptomatic benign prostatic hyperplasia (BPH). CASE PRESENTATION: Two patients with severe HA and lower urinary tract symptoms (LUTS) not responding to medical therapy underwent PAE at our institution. In both patients, intermittent administration of decreasing doses of extended half-life recombinant factor VIII (EHL rFVIII) concentrate from 30 min before to 7 days after the PAE resulted in good hemostatic control. In addition to EHL rFVIII, tranexamic acid was administered in the same timeframe to augment the action of EHL rFVIII and to account for possible mucosal bleeding from the urinary tract. Both patients reported a minor localized hematoma at the femoral puncture site in the right groin, that resolved spontaneously. No other bleeding complications were observed. CONCLUSIONS: The procoagulant effects of the chosen dosing of EHL rFVIII showed sufficient to perform a technically successful embolization. At 6 months follow-up, both patients had significant reduction in self-reported urinary symptoms and were content with the outcome.

Assessment of Liver Fat: Dual-Energy CT versus Conventional CT with and without Contrast.

We assessed the correlation between liver fat percentage using dual-energy CT (DECT) and Hounsfield unit (HU) measurements in contrast and non-contrast CT. This study included 177 patients in two patient groups: Group A (n = 125) underwent whole body non-contrast DECT and group B (n = 52) had a multiphasic DECT including a conventional non-contrast CT. Three regions of interest were placed on each image series, one in the left liver lobe and two in the right to measure Hounsfield Units (HU) as well as liver fat percentage. Linear regression analysis was performed for each group as well as combined. Receiver operating characteristic (ROC) curve was generated to establish the optimal fat percentage threshold value in DECT for predicting a non-contrast threshold of 40 HU correlating to moderate-severe liver steatosis. We found a strong correlation between fat percentage found with DECT and HU measured in non-contrast CT in group A and B individually (R2 = 0.81 and 0.86, respectively) as well as combined (R2 = 0.85). No significant difference was found when comparing venous and arterial phase DECT fat percentage measurements in group B (p = 0.67). A threshold of 10% liver fat found with DECT had 95% sensitivity and 95% specificity for the prediction of a 40 HU threshold using non-contrast CT. In conclusion, liver fat quantification using DECT shows high correlation with HU measurements independent of scan phase.

Center experience and other determinants of patient radiation exposure during prostatic artery embolization: a retrospective study in three Scandinavian centers.

OBJECTIVES: To evaluate the effects of center experience and a variety of patient- and procedure-related factors on patient radiation exposure during prostatic artery embolization (PAE) in three Scandinavian centers with different PAE protocols and levels of experience. Understanding factors that influence radiation exposure is crucial in effective patient selection and procedural planning. METHODS: Data were collected retrospectively for 352 consecutive PAE procedures from January 2015 to June 2020 at the three centers. Dose area product (DAP (Gy·cm2)) was selected as the primary outcome measure of radiation exposure. Multiple patient- and procedure-related explanatory variables were collected and correlated with the outcome variable. A multiple linear regression model was built to determine significant predictors of increased or decreased radiation exposure as reflected by DAP. RESULTS: There was considerable variation in DAP between the centers. Intended unilateral PAE (p = 0.03) and each 10 additional patients treated (p = 0.02) were significant predictors of decreased DAP. Conversely, increased patient body mass index (BMI, p < 0.001), fluoroscopy time (p < 0.001), and number of digital subtraction angiography (DSA) acquisitions (p < 0.001) were significant predictors of increased DAP. CONCLUSIONS: To minimize patient radiation exposure during PAE radiologists may, in collaboration with clinicians, consider unilateral embolization, pre-interventional CTA for procedure planning, using predominantly anteroposterior (AP) projections, and limiting the use of cone-beam CT (CBCT) and fluoroscopy. KEY POINTS: • Growing center experience and intended unilateral embolization decrease patient radiation exposure during prostatic artery embolization. • Patient BMI, fluoroscopy time, and number of DSA acquisitions are associated with increased DAP during procedures. • Large variation in radiation exposure between the centers may reflect the use of CTA before and CBCT during the procedure.

Pressure Difference Estimation in Non-stenotic Carotid Bifurcation Phantoms Using Vector Flow Imaging.

Local pressure differences estimated using vector flow imaging (VFI) and direct catheterization in seven carotid bifurcation phantoms were compared with simulated pressure fields. VFI correlated strongly with simulated peak pressure differences (r = 0.99, p < 0.00001), with an average overestimation of 12.3 Pa (28.6%). The range between the lowest and highest pressure difference of VFI underestimated simulations by 4.6 Pa (8.06%; r = 0.99, p < 0.0001). The catheter method exhibited no correlation (r = -0.09, p = 0.85). Ten repeated measurements on one phantom revealed a small standard deviation (SD) for VFI (SD = 8.4%, mean estimated SD = 11.5%), but not for the catheter method (SD = 785.6%). An in vivo peak systolic pressure difference of 97.9 Pa (estimated SD = 30%) was measured using VFI in one healthy individual. This study indicates that VFI pressure difference estimation is feasible in phantoms and in vivo and realistic estimates of the SD can be attained from the data.

Efficacy of dexamethasone in reducing the postembolisation syndrome in men undergoing prostatic artery embolisation for benign prostatic hyperplasia: protocol for a single-centre, randomised, double-blind, placebo-controlled trial-the 'DEXAPAE' study.

INTRODUCTION: Postembolisation syndrome (PES) is the most common side effect of vascular embolisation of solid organs. Although prophylactic corticosteroids are known to reduce the incidence and severity of PES, no trials investigating their efficacy have been conducted in men undergoing prostatic artery embolisation (PAE). We postulate that steroids can have a similar effect in reducing PES after PAE. This paper describes the rationale and detailed protocol for a randomised controlled trial evaluating the efficacy of dexamethasone (DEXA) in reducing PES after PAE. METHODS AND ANALYSIS: In this single-centre, randomised, double-blind, placebo-controlled trial, we will enrol 60 individuals undergoing PAE for benign prostatic hyperplasia. Participants will be randomised to receive IV DEXA (24 mg) or placebo (saline). The primary outcomes will be postprocedural fever, pain and quality of life. The secondary outcomes will include postprocedural nausea, postprocedural medicine usage, laboratory parameters (C reactive protein, prostate-specific antigen) and early PAE results. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Danish Committee on Health Research Ethics in the Capital Region (H-20025910). The results from this trial will be disseminated through publication in peer-reviewed journals and national and international presentations. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov identifier: NCT04588857; EudraCT number: 2020-000915-53.

Transthoracic Vector Flow Imaging in Pediatric Patients with Valvular Stenosis - A Proof of Concept Study.

Purpose Continuous wave Doppler ultrasound is routinely used to detect cardiac valve stenoses. Vector flow imaging (VFI) is an angle-independent real-time ultrasound method that can quantify flow complexity. We aimed to evaluate if quantification of flow complexity could reliably assess valvular stenosis in pediatric patients. Materials and Methods Nine pediatric patients with echocardiographically confirmed valvular stenosis were included in the study. VFI and Doppler measurements were compared with transvalvular peak-to-peak pressure differences derived from invasive endovascular catheterization. Results Vector concentration correlated with the catheter measurements before intervention after exclusion of one outlier (r=-0.83, p=0.01), whereas the Doppler method did not (r=0.49, p=0.22). The change in vector concentration after intervention correlated strongly with the change in the measured catheter pressure difference (r=-0.86, p=0.003), while Doppler showed a tendency for a moderate correlation (r=0.63, p=0.07). Conclusion Transthoracic flow complexity quantification calculated from VFI data is feasible and may be useful for assessing valvular stenosis severity in pediatric patients.

Current Status of Trans-Arterial Embolization in Pain Management of Musculoskeletal Inflammatory Conditions - An Evidence-Based Review.

OBJECTIVE: To summarize the literature on trans-arterial embolization in inflammatory musculoskeletal conditions, focusing on efficacy and safety. MATERIALS AND METHODS: PRISMA guidelines were followed. A systematic literature search revealed 19 studies, with a total of 394 participants, eligible for inclusion. RESULTS: The included studies consisted of case reports/series and non-randomized interventional studies, with knee osteoarthritis and adhesive capsulitis of the shoulder as the most frequent conditions. In all studies except one, pain was reduced up to four years after treatment. All adverse events were transient. Due to high heterogeneity, meta-analysis was not possible. CONCLUSION: The included early studies showed encouraging results regarding efficacy and safety. However, randomized, placebo-controlled trials are warranted.