US of the Penis: Beyond Erectile Dysfunction.

High-frequency US, with a linear transducer and gray-scale, color, and spectral Doppler US techniques, is the primary imaging modality for evaluation of the penis. It can allow delineation of anatomy and assessment of dynamic blood flow; it is easily available and noninvasive or minimally invasive; it is cost effective; and it is well tolerated by patients. US assessment after pharmacologic induction of erection is an additional tool in assessing patients with suspected vasculogenic impotence, and also in selected patients with penile trauma and suspected Peyronie disease. Penile injuries, life-threatening infections, and vascular conditions such as priapism warrant rapid diagnosis to prevent long-term morbidities due to clinical misdiagnosis or delayed treatment. US can facilitate a timely diagnosis in these emergency conditions, even at the point of care such as the emergency department, which can facilitate timely treatment. In addition, color and spectral Doppler US are valuable applications in the follow-up of patients treated with endovascular revascularization procedures for vasculogenic erectile dysfunction. Image optimization and attention to meticulous techniques including Doppler US is vital to improve diagnostic accuracy. Radiologists should be familiar with the detailed US anatomy, pathophysiologic characteristics, scanning techniques, potential pitfalls, and US manifestations of a wide spectrum of vascular and nonvascular penile conditions to suggest an accurate diagnosis and direct further management. The authors review a range of common and uncommon abnormalities of the penis, highlight their key US features, discuss differential diagnosis considerations, and briefly review management. ©RSNA, 2024 Supplemental material is available for this article.

Intraprocedural, Intra-Arterial CT Foot Perfusion Examination for Assessment of Endovascular Therapy in Patients With Critical Limb Ischemia: A Prospective Pilot Study.

BACKGROUND: Current techniques to evaluate computed tomography (CT) foot perfusion in patients with critical limb ischemia use high contrast doses and cannot be used during endovascular procedures. CT perfusion of the foot with intra-arterial contrast injection during endovascular treatment in a hybrid angiography CT suite might solve these problems. PURPOSE: The main objective of this study was to evaluate whether intra-arterial CT foot perfusion using a hybrid CT angiosystem is feasible during endovascular treatment for critical limb ischemia. MATERIAL AND METHODS: This prospective pilot study investigated intraprocedural, intra-arterial CT perfusion of the foot using a hybrid CT angiosystem in 12 patients before and after endovascular treatment for critical limb ischemia. Time to peak (TTP) and arterial blood flow were measured before and after treatment and compared using a paired t test. RESULTS: All 24 CT perfusion maps could be calculated adequately. The contrast volume used for one perfusion CT scan was 4.8 ml. The mean TTP before treatment was 12.8 seconds (standard deviation [SD] 2.8) and the mean TTP posttreatment was 8.4 seconds (SD 1.7), this difference being statistically significant (p=.001). Tendency toward increased blood flow after treatment, 340 ml/min/100 ml (SD 174) vs 514 ml/min/100 ml (SD 366) was noticed (p=.104). The mean effective radiation dose was 0.145 mSv per scan. CONCLUSION: Computed tomography perfusion of the foot with low contrast dose intra-arterial contrast injection during endovascular treatment in a hybrid angiography CT suite is a feasible technique. CLINICAL IMPACT: Intra-arterial CT foot perfusion using a hybrid CT-angiography system is a feasible new technique during endovascular therapy for critical limb ischemia to assess the results of the treament. Future research is necessary in defining endpoints of endovascular treatment and establishing its role in limb salvage prognostication.

Randomized Controlled Trial Comparing Drug-coated Balloon Angioplasty versus Conventional Balloon Angioplasty for Treating Below-the-Knee Arteries in Critical Limb Ischemia: The SINGA-PACLI Trial.

Background There is a paucity of randomized trials demonstrating superior efficacy of drug-coated balloon angioplasty (DCBA) compared with conventional percutaneous transluminal angioplasty (PTA) for below-the-knee arterial disease in patients with -critical limb ischemia. Purpose To compare DCBA versus PTA for below-the-knee lesions in participants with critical limb ischemia through 12 months. Materials and Methods In this prospective, randomized, two-center, double-blind superiority study, participants with critical limb ischemia with rest pain or tissue loss with atherosclerotic disease in the native below-the-knee arteries were randomly assigned (in a one-to-one ratio) to DCBA or PTA after stratification for diabetes and renal failure between November 2013 and October 2017. The primary efficacy end point was angiographic primary patency at 6 months analyzed on an intention-to-treat basis. Secondary end points through 12 months were composed of major adverse events including death and major amputations, wound healing, limb salvage, clinically driven target-lesion revascularization, and amputation-free survival. Primary and binary secondary end points, analyzed by using generalized-linear model and time-to-event analyses, were estimated with Kaplan-Meier survival curves and hazard ratios (Cox regression). Results Seventy participants (mean age, 61 years ± 10 [standard deviation]; 43 men) in the DCBA group and 68 (mean age, 64 years ± 10; 50 men) in the PTA group were evaluated. The percentage of patients with angiographic primary patency at 6 months was 43% (30 of 70) in the DCBA group and 38% (26 of 68) in the PTA group (P = .48). Through 12 months, the percentage of deaths was similar: 21% in the DCBA group and 16% in the PTA group (P = .43). Amputation-free survival rate assessed with Kaplan-Meier curves differed through 12 months: 59% (41 of 70) in the DCBA group compared with 78% (53 of 68) in the PTA group (P = .01). Conclusion In participants with critical limb ischemia, the drug-coated balloon angioplasty group and the conventional percutaneous transluminal angioplasty group had similar primary patency rates at 6 months after treatment of below-the-knee arteries. Amputation-free survival rates through 12 months were higher in the percutaneous transluminal angioplasty group. © RSNA, 2021 Online supplemental material is available for this article.

Systematic Review and Meta-Analysis of Prophylactic Transarterial Embolization for High-Risk Bleeding Peptic Ulcer Disease.

The present systematic review determined the role of transarterial embolization (TAE) as a prophylactic treatment in bleeding peptic ulcers after initial successful endoscopic hemostasis. PubMed and Ovid Medline databases were searched from inception until July 2019 for studies that included patients deemed high-risk based on Forrest Classification, Rockall score ≥ 5, or endoscopic evaluation in addition to those who underwent prophylactic TAE after initial successful endoscopic hemostasis. Meta-analysis was performed to compare patients who underwent endoscopic therapy (ET) and TAE with those who underwent ET alone. The primary outcomes measured included rates of rebleeding, reintervention, and 30-day mortality. Secondary outcome measures evaluated length of hospitalization, technical success rates, and complications associated with TAE. Of 916 publications, 5 were eligible for inclusion; 310 patients with high-risk peptic ulcer bleeding underwent prophylactic TAE, and 255 were compared against a control group of 580 patients that underwent standard treatment with ET alone. Patients who underwent ET with TAE had lower 30-day rebleeding rates (odds ratio [OR], 0.35; 95% confidence interval [CI] 0.15-0.85; P = .02; I2 = 50%). The ET with TAE group had a lower 30-day mortality rate (OR, 0.28; 95% CI, 0.10-0.83; P = .02; I2 = 58%). There was no difference in pooled reintervention rates (OR, 0.68; 95% CI, 0.43-1.08; P = .10; I2 = 0%) and length of hospitalization (mean difference, -0.32; 95% CI, -1.88 to 1.24; P = .69; I2 = 0%). Technical success rate of prophylactic TAE was 90.5% (95% CI, 83.09-97.98; I2 = 75.9%). Pooled proportion of overall complication rate was 0.18% (95% CI, 0.00-1.28; I2 = 0%). Prophylactic TAE has lower rebleeding and mortality with a good success rate and low complications. Prophylactic TAE after primary ET may be recommended for selected patients with high-risk bleeding ulcers; however, further studies should be performed to establish this as a routine tool in patients with bleeding peptic ulcer disease.

Effect of short-term low molecular weight heparin on patency following successful salvage of arteriovenous access with recurrent thrombosis.

AIM: This study aims to investigate the effect of low molecular weight heparin (LMWH) in maintaining the patency of arteriovenous (AV) access with recurrent thrombosis. METHODS: Following successful thrombectomy, 66 patients with recurrent thrombosis were included in the study. The primary, assisted primary and secondary patency rates of patients who received LMWH (n = 24) were compared with those who did not receive anticoagulant (n = 42) using Kaplan-Meier analysis. Cox-regression analysis was performed to investigate potential predictors of patency rates. RESULTS: The mean dose of enoxaparin used was 40 ± 13.1 mg or 0.74 ± 0.2 mg/kg daily for a median duration of 14 (IQR 7,28) days. The mean trough anti-Xa concentrations measured after two doses of LMWH was 0.17 ± 0.13 IU/mL. Kaplan-Meier analyses for mean primary, assisted primary and secondary patency rates of LMWH vs no anticoagulation groups were 149 (95% CI: 91 - 207) vs 87 (95% CI: 42-132) days (P < .006), 230 (95% CI: 142-320) vs 107 (95% CI: 62-150) days (P = .01) and 438 (299-579) vs 294 (95% CI: 197-392) days (P = .08) respectively. LMWH remained a significant protective predictor of primary (HR: 0.49; 95% CI: 0.25-0.86; P = .02) and assisted primary patency rates (HR: 0.51; 95% CI: 0.27-0.98; P = .04) after adjusting for patient age, access age, type of AV access, presence of peripheral vascular disease and haemoglobin levels. CONCLUSION: LMWH may improve short and mid-term patency rates for AV accesses with recurrent thrombosis.

Outcomes of endovascular salvage of clotted arteriovenous access and predictors of patency after thrombectomy.

OBJECTIVE: This study aimed to report the outcomes of endovascular salvage of clotted arteriovenous (AV) accesses and to determine potential predictors of poor patency rates after thrombectomy. METHODS: Records of hemodialysis patients who underwent endovascular salvage of clotted AV access were reviewed retrospectively. Technical and clinical success rates, complication rates, and 3- and 6-month patency rates were determined. Multivariate analysis was performed to determine the predictors of patency after thrombectomy. RESULTS: A total of 294 patients underwent endovascular salvage of clotted AV access during the study period; 156 patients had arteriovenous fistula, whereas the remaining 138 were arteriovenous grafts (AVGs). The technical and clinical success rates were 96.3% and 93.2%; the major and minor complication rates were 0.7% and 9.9%. Post-thrombectomy primary, assisted primary, and secondary patency rates were 62.9%, 76.2%, and 77.6% at 3 months and 43.9%, 59.5%, and 61.6% at 6 months. The patency rates were significantly better for arteriovenous fistula than for AVG except for 6-month assisted primary and secondary patency. Multivariate Cox regression analysis showed that prior thrombosis within 90 days was significantly associated with loss of primary patency (hazard ratio [HR], 1.90; 95% confidence interval [CI], 1.21-2.98; P < .01), assisted primary patency (HR, 2.42; 95% CI, 1.42-4.13; P < .01), and secondary patency (HR, 2.52; 95% CI, 1.40-4.53; P < .01). Having an AVG was also negatively associated with primary patency. CONCLUSIONS: Most clotted AV accesses can be salvaged by endovascular technique. Recurrent thrombosis within 90 days is associated with poor short- and long-term patency even after successful endovascular reinterventions.

Outcome and Distal Access Patency in Subintimal Arterial Flossing with Antegrade-Retrograde Intervention for Chronic Total Occlusions in Lower Extremity Critical Limb Ischemia.

PURPOSE: To report the outcome and distal access patency of the Subintimal Arterial Flossing with Antegrade-Retrograde Intervention (SAFARI) technique for chronic total occlusion (CTO) in critical limb ischemia (CLI). MATERIALS AND METHODS: From January 2009 to June 2015, 220 SAFARI procedures were performed for 200 limbs in 191 patients (108 males [56.5%]; median age, 70 years old; range, 36 to 97 years old) with CLI (9.4% were Fontaine classification 3; and 90.6% were Fontaine classification 4). Distal access was obtained from the distal superficial femoral artery (n = 6), popliteal artery (n = 49), anterior tibial artery (n = 56), dorsalis pedis (n = 51), peroneal artery (n = 12), posterior tibial artery (n = 45), and lateral plantar artery (n = 1). Distal access hemostasis was obtained with internal balloon tamponade in 71.4% (n = 157). Outcome measurements were technical success, freedom from major amputation and complications. Preprocedural angiograms of clinically driven repeat interventions were reviewed in 73 cases for distal access patency. RESULTS: Technical success was achieved in 80.5% (n = 177). Reasons for technical failure include inability to obtain distal access (n = 3), cross the occlusion retrogradely (n = 16), re-enter the true lumen (n = 9), and achieve antegrade blood flow after the procedure (n = 15). Freedom from major amputation for technically successful procedures was 84.7%, 82.9%, and 81.9% at 6, 12, and 24 months, respectively. There were 3 cases of distal access bleeding with 1case that required coil embolization. The distal access remained patent in 80.8% of observable cases with repeated endovascular intervention. CONCLUSIONS: Distal retrograde arterial access (SAFARI) technique is safe and effective in the treatment of CTOs in the context of CLI, after failure of antegrade revascularization.

"Angioplasty-First" Approach for Limb Salvage in Asian Patients with Critical Limb Ischemia: Outcomes from 3,303 Angioplasties on 2,402 Limbs in a Single Tertiary Hospital.

PURPOSE: To review outcomes of patients with critical limb ischemia (CLI) who underwent conventional percutaneous transluminal angioplasty (PTA) as first-line treatment for revascularization. MATERIALS AND METHODS: Retrospective review of 3,303 angioplasty procedures on 2,402 limbs in 1,968 patients with CLI was conducted. Mean patient age was 68 years ± 11, and 1,057 patients (54%) were male. Diabetes mellitus (DM) was present in 1,736 patients (88%), and end-stage renal disease (ESRD) in 579 (29%). A majority of patients (90%) had tissue loss. Limb salvage rates were generated by Kaplan-Meier plot. Univariate and multivariate Cox regression analysis was conducted to investigate associations between clinical predictors and time-to-event outcome. RESULTS: Limb salvage rates at 1, 3, 5, and 10 years were 75%, 73%, 72%, and 62%, respectively, and overall survival rates were 79%, 64%, 56%, and 34%, respectively. In multivariable Cox regression analysis with the outcome of major amputation, significant predictors included age < 69 years (P = .032), Malay race (P = .029), DM (P < .001), history of cerebral vascular disease (P = .003), ESRD (P < .001), Rutherford classification (P = .042), repeat intervention (P = .034), and number of straight-line flows (P < .001) and plantar arch integrity (P < .001) on completion angiography. Significant associations with mortality were age < 69 years (P < .001), male sex (P = .030), Malay race (P = .027), history of ischemic heart disease (P < .001), ESRD (P < .001), and repeat intervention (P < .001). CONCLUSIONS: PTA as first-line revascularization for patients with CLI is safe and effective. Further studies are suggested to validate the outcome predictive model.

Preparing IR for COVID-19: The Singapore Experience.

This paper describes country-wide special measures undertaken for interventional radiology staff during the current coronavirus disease 2019 (COVID-19) pandemic. Although each interventional radiology service around the world faces unique challenges, the principles outlined in this article will be useful when designing or strengthening individual practices and integrating them within wider hospital and national measures. Moving beyond the current outbreak, these measures will be useful for any future infectious diseases which are likely to arise.

Diagnostic Ultrasound Services During the Coronavirus Disease (COVID-19) Pandemic.

OBJECTIVE. Nosocomial transmission of coronavirus disease (COVID-19) to frontline health care workers is well known, and health care workers may inadvertently become vectors for onward transmission. Ultrasound (US) service providers are at significant risk because scanning usually requires prolonged close patient contact. The bulky US equipment may also facilitate fomite transmission of disease. With increasing use of point-of-care and portable diagnostic US services, the risk is substantial. CONCLUSION. Our experience and protocols may help service providers with their own effective response against COVID-19.

Case 265: Lemmel Syndrome or Biliary Obstruction Due to a Periampullary Duodenal Diverticulum.

History A 70-year-old man presented to the emergency department with fever, chills, rigors, and upper abdominal discomfort. Physical examination revealed jaundice and mild right upper quadrant tenderness. Laboratory tests revealed an increased C-reactive protein level of 133 mg/L (normal range, 0.2-0.9 mg/L), a white blood cell count of 11.69 ×109/L (normal range, 4-10 ×109/L), and an obstructive pattern on liver function tests, with a total bilirubin level of 3.5 mg/dL (59.9 µmol/L) (normal range, 0.4-1.9 mg/dL [6.8-32.5 µmol/L]), an alkaline phosphatase level of 716 U/L (11.9 µkat/L) (normal range, 39-99 U/L [0.65-1.65 µkat/L]), and an aspartate aminotransferase level of 88 U/L (1.47 µkat/L) (normal range, 12-42 U/L [0.20-0.70 µkat/L]). Serum amylase level was within normal limits at 84 U/L (1.40 µkat/L) (normal range, 38-149 U/L [0.63-2.48 µkat/L]). A clinical diagnosis of hepatobiliary sepsis due to ascending cholangitis was made. Relevant medical history included gastric carcinoma treated with a Billroth II surgical procedure 17 years earlier that was performed in conjunction with cholecystectomy. In addition, there were episodes of ascending cholangitis 6-12 months prior to the current admission that were managed conservatively with antibiotics at another institution. Blood cultures were positive for Klebsiella oxytoca. Administration of intravenous antibiotics was started, and CT examination of the abdomen was performed. Because a previous Billroth II procedure had been performed, the patient underwent percutaneous transhepatic cholangiography.

Case 265.

History A 70-year-old man presented to the emergency department with fever, chills, rigors, and upper abdominal discomfort. Physical examination revealed jaundice and mild right upper quadrant tenderness. Laboratory tests revealed an increased C-reactive protein level of 133 mg/L (normal range, 0.2-0.9 mg/L), a white blood cell count of 11.69 ×109/L (normal range, 4-10 ×109/L), and an obstructive pattern on liver function tests, with a total bilirubin level of 3.5 mg/dL (59.9 µmol/L) (normal range, 0.4-1.9 mg/dL [6.8-32.5 µmol/L]), an alkaline phosphatase level of 716 U/L (11.9 µkat/L) (normal range, 39-99 U/L [0.65-1.65 µkat/L]), and an aspartate aminotransferase level of 88 U/L (1.47 µkat/L) (normal range, 12-42 U/L [0.20-0.70 µkat/L]). Serum amylase level was within normal limits at 84 U/L (1.40 µkat/L) (normal range, 38-149 U/L [0.63-2.48 µkat/L]). A clinical diagnosis of hepatobiliary sepsis due to ascending cholangitis was made. Relevant medical history included gastric carcinoma treated with a Billroth II surgical procedure 17 years earlier that was performed in conjunction with cholecystectomy. In addition, there were episodes of ascending cholangitis 6-12 months prior to the current admission that were managed conservatively with antibiotics at another institution. Blood cultures were positive for Klebsiella oxytoca. Administration of intravenous antibiotics was started, and CT examination of the abdomen was performed ( Fig 1 ). Because a previous Billroth II procedure had been performed, the patient underwent percutaneous transhepatic cholangiography ( Fig 2 ). Figure 1a: (a) Arterial phase axial CT image at the level of the pancreatic head. (b) Portal venous phase coronal reformatted CT image shows the upper abdomen. Figure 1b: (a) Arterial phase axial CT image at the level of the pancreatic head. (b) Portal venous phase coronal reformatted CT image shows the upper abdomen. Figure 2: Fluoroscopic image obtained with percutaneous transhepatic cholangiography during the most recent admission.

Paclitaxel-coated balloon in the treatment of recurrent dysfunctional arteriovenous access, real-world experience and longitudinal follow up.

AIM: Dysfunctional arteriovenous (AV) access remains a significant cause of morbidity and hospital admission for patients with end stage renal failure on haemodialysis. This study was performed to evaluate the impact of paclitaxel-coated Balloon (PCB) on the patency of AV access with recurrent stenoses. METHODS: We retrospectively studied haemodialysis patients who presented to our centre with recurrent AV access dysfunction and compared intervention-free patency using plain balloon versus PCB. RESULTS: A total of 147 patients were followed up longitudinally. Intervention-free patency was better following PCB compared to previous intervention using plain balloons (6.4 ± 5.8 versus 4.0 ± 3.7, P < 0.01). The 3- and 6-month patency rates after PCB were significantly better compared to standard plain angioplasty balloon: 69.4% versus 52.4%, P < 0.01 and 42.9% versus 15.6%, P < 0.01 respectively. Kaplan-Meier survival analysis of circuit patency demonstrated the superiority of PCB over plain balloon angioplasty in both arteriovenous fistula and arteriovenous graft (P < 0.01 and P = 0.01 respectively) although the patency of arteriovenous fistula remained significantly better than arteriovenous graft following interventions with PCB (P < 0.01). Age of AV access and the number of previous interventions were found to be significant predictors of patency following PCB intervention. CONCLUSION: Arteriovenous access intervention with PCB was shown to be superior compared to plain balloon in the treatment of both non-thrombosed and thrombosed AV accesses in our multi-ethnic population.

Hemodialysis Arteriovenous Fistula and Graft Stenoses: Randomized Trial Comparing Drug-eluting Balloon Angioplasty with Conventional Angioplasty.

Purpose To compare lesion primary patency and restenosis rates between drug-eluting balloon (DEB) percutaneous transluminal angioplasty (PTA) and conventional balloon PTA (cPTA) in the treatment of arteriovenous fistula (AVF) and arteriovenous graft (AVG) stenosis. Materials and Methods In this prospective study, 119 participants (mean age, 59.2 years; 79 men, 40 women) with failing AVFs (n = 98) or AVGs (n = 21) were randomly assigned to undergo either DEB PTA (n = 59) or cPTA (n = 60) from January 2012 to May 2013. Primary end points were lesion primary patency and restenosis rates at 6 months; secondary outcomes were anatomic and clinical success after PTA, circuit primary patency at 6 months and 1 year, and lesion primary patency at 1 year. Statistical analysis was performed by using the Kaplan-Meier product limit estimator, and hazard ratio was calculated by using Cox proportional hazards regression. Complication rates were assessed in both groups. Results Estimated lesion primary patency in the DEB PTA and cPTA arms was 0.81 and 0.61, respectively, at 6 months (P = .03) and 0.51 and 0.34, respectively, at 1 year (P = .04). Estimated circuit primary patency in the DEB PTA and cPTA arms was 0.76 and 0.56, respectively, at 6 months (P = .048) and 0.45 and 0.32, respectively, at 1 year (P = .16). Restenosis rate was 34.0% (16 of 47) for DEB PTA and 62.9% (22 of 35) for cPTA at 6 months (P = .01). No major complications were noted. Conclusion Drug-eluting balloon angioplasty was effective in prolonging lesion primary patency of dialysis access stenoses at 6 months and 1 year. © RSNA, 2018.

A pilot study on adjunctive use of parametric colour-coded digital subtraction angiography in endovascular interventions of haemodialysis access.

BACKGROUND: Two-dimensional digital subtraction angiography (DSA) is the gold standard for angiographic evaluation of dysfunctional haemodialysis access. We aim to investigate the utility of parametric colour coded DSA in providing hemodynamic analysis during haemodialysis access interventions. METHODS: We retrospectively studied 20 patients who underwent access intervention and applied parametric colour-coding on selected DSA acquisitions before and after percutaneous transluminal angioplasty (PTA). The difference in time to peak (dTTP) contrast enhancement and time attenuation curve (TAC) of pre- and post-stenotic regions of interest (ROIs) were obtained and compared after treatment. RESULTS: Improvements were seen in mean percent of stenosis after PTA (p < 0.0001) for all cases. Median dTTP improved from 0.52 (IQR 0.26, 0.8) to 0.25 (IQR 0, 0.26) seconds (p = 0.001). Median 50% contrast washout time improved from 0.77 (IQR 0.39, 1.17) to 0.42 (IQR 0.23, 0.59) seconds (p = 0.031). Significant correlation was seen for dTTP vs. percent of stenosis (r = 0.723, p = 0.043) pre-PTA and for change in dTTP vs. percent change in stenosis post-PTA (r = 0.786, p = 0.021) for inflow lesions. Such correlation was however not seen in outflow lesions. CONCLUSIONS: Adjunctive use of parametric colour-coded DSA may provide potentially useful hemodynamic information during vascular access interventions. Larger prospective studies are needed to validate our findings.

Diagnosis and Management of Complications from Percutaneous Biliary Tract Interventions.

Complications related to percutaneous biliary tract interventions (PBTIs) can range from access site discomfort to life-threatening vascular complications. These complications are relatively uncommon, and most of them are self-limiting. However, major complications for which an increased level of patient care and/or a prolonged hospital stay are required and that may lead to death-albeit rarely-can occur. Some of the most common complications related to PBTI include pain, infection, bile leakage, and catheter blockage. These conditions can be easily recognized by using the patient's clinical history and laboratory examination results. However, the more uncommon complications, such as life-threatening hemobilia, acute pancreatitis, and catheter and stent fractures, may have nonspecific clinical manifestations, and the underlying pathologic condition may be found only when it is being sought specifically. It is important that diagnostic and interventional radiologists be aware of the wide spectrum of PBTI-related complications, as early recognition and treatment may prevent catastrophic situations. In addition, knowledge of the different treatment options is essential for guidance in interventional radiology procedures such as transarterial control of hemobilia, imaging-guided direct percutaneous embolization of pseudoaneurysms, and percutaneous treatment of catheter- and stent-related complications such as fractures. The authors review a wide spectrum of complications associated with PBTI and the percutaneous management of these conditions. They also highlight valuable lessons learned from morbidity and mortality rounds at a high-volume tertiary care center. ©RSNA, 2017.

Current role of selective internal radiation with yttrium-90 in liver tumors.

An expert panel met to review the evidence for selective internal radiation therapy (SIRT) using yttrium-90 microspheres in hepatocellular carcinoma and metastases from colorectal cancer and neuroendocrine tumors. There is now convincing evidence for the safety and efficacy of SIRT in these situations albeit mostly from retrospective cohort studies. There are a number of ongoing prospective randomized controlled clinical trials investigating the role of SIRT in liver tumors; however, data from these trials are still several years away (although the SIRFLOX study has been recently published). In this evolving environment, published evidence and the authors' experience were used to summarize the current and potential role of SIRT in the management of hepatocellular carcinoma of intermediate or advanced stage and in liver-dominant metastatic colorectal cancer and metastatic neuroendocrine tumors.

Randomized clinical trial of cutting balloon angioplasty versus high-pressure balloon angioplasty in hemodialysis arteriovenous fistula stenoses resistant to conventional balloon angioplasty.

PURPOSE: To compare the efficacy and safety of cutting balloon angioplasty (CBA) versus high-pressure balloon angioplasty (HPBA) for the treatment of hemodialysis autogenous fistula stenoses resistant to conventional percutaneous transluminal angioplasty (PTA). MATERIALS AND METHODS: In a prospective, randomized clinical trial involving patients with dysfunctional, stenotic hemodialysis arteriovenous fistulas (AVFs), patients were randomized to receive CBA or HPBA if conventional PTA had suboptimal results (ie, residual stenosis > 30%). A total of 516 patients consented to participate in the study from October 2008 to September 2011, 85% of whom (n = 439) had technically successful conventional PTA. The remaining 71 patients (mean age, 60 y; 49 men) with suboptimal PTA results were eventually randomized: 36 to the CBA arm and 35 to the HPBA arm. Primary and secondary target lesion patencies were determined by Kaplan-Meier analysis. RESULTS: Clinical success rates were 100% in both arms. Primary target lesion patency rates at 6 months were 66.4% and 39.9% for CBA and HPBA, respectively (P = .01). Secondary target lesion patency rates at 6 months were 96.5% for CBA and 80.0% for HPBA (P = .03). There was a single major complication of venous perforation following CBA. The 30-day mortality rate was 1.4%, with one non-procedure-related death in the HPBA group. CONCLUSIONS: Primary and secondary target lesion patency rates of CBA were statistically superior to those of HPBA following suboptimal conventional PTA. For AVF stenoses resistant to conventional PTA, CBA may be a better second-line treatment given its superior patency rates.

Severe acute respiratory syndrome: 11 years later--a radiology perspective.

OBJECTIVE: Severe acute respiratory syndrome (SARS) was a highly virulent atypical pneumonia caused by a novel coronavirus that resulted in a pandemic in 2003. Singapore was one of the most severely affected countries, and SARS took a heavy toll on our health care system. The lessons learned during the pandemic have shaped our national contagion response plan and have proved valuable in subsequent epidemics. We describe the lessons learned for the radiology department. CONCLUSION: Our experience with SARS has shaped and changed our daily practice of radiology.