Case report: Deep vein arterialization for limb salvage in a patient with subacute limb ischemia.

BACKGROUND: Successful revascularization of the lower extremity is key to avoiding amputation in patients with subacute limb ischemia. Percutaneous deep vein arterialization (DVA) is a novel endovascular technique which allows the shunting of blood through an arteriovenous fistula and native vein into the lower limb, typically employed in no-option chronic limb-threatening ischemia. METHOD: We present a case illustrating the unconventional use of DVA for limb salvage in a patient presenting with subacute limb ischemia refractive to surgical treatment, endovascular revascularization, and medical therapy. RESULT AND CONCLUSION: The arteriovenous anastomosis allowed for the reconstitution of arterial inflow to the patient's foot, thereby avoiding major limb amputation. CONCLUSION: The conventional knowledge that DVA neo-conduits require maturation limiting its role in the treatment of subacute limb ischemia is challenged. However, further research is needed to establish its role and effectiveness for subacute limb ischemia.

Comparative Study of Ablation Zone of EMPRINT HP Microwave Device with Contemporary 2.4 GHz Microwave Devices in an Ex Vivo Porcine Liver Model.

(1) Background: Percutaneous microwave ablation (MWA) is an accepted treatment of non-operative liver cancer. This study compares the ablation zones of four commercially available 2.45 GHz MWA systems (Emprint, Eco, Neuwave, and Solero) in an ex vivo porcine liver model. (2) Methods: Ex vivo porcine livers (n = 85) were obtained. Two ablation time setting protocols were evaluated, the manufacturer's recommended maximum time and a 3 min time, performed at the manufacturer-recommended maximum power setting. A total of 236 ablation samples were created with 32 (13.6%) samples rejected. A total of 204 samples were included in the statistical analysis. (3) Results: For single-probe protocols, Emprint achieved ablation zones with the largest SAD. Significant differences were found in all comparisons for the 3 min time setting and for all comparisons at the 10 min time setting except versus Neuwave LK15 and Eco. Emprint produced ablation zones that were also significantly more spherical (highest SI) than the single-probe ablations from all other manufacturers. No statistical differences were found for ablation shape or SAD between the single-probe protocols for Emprint and the three-probe protocols for Neuwave. (4) Conclusions: The new Emprint HP system achieved large and spherical ablation zones relative to other 2.45 GHz MWA systems.

Clinicopathological and treatment response characteristics of updated rhabdomyosarcoma histomolecular subtypes: An Asian population-based study.

AIM: New histomolecular subtypes of rhabdomyosarcoma have recently been defined but their corresponding clinical characteristics are not well described. Also, these clinical phenotypes vary greatly by age and ethnicity but have not been profiled in Asian populations. Thus, we sought to determine the landscape of rhabdomyosarcoma subtypes in a national Asian cohort and compare clinical characteristics among age groups and molecular subtypes. METHODS: We performed a retrospective population-based study of all rhabdomyosarcoma patients in Singapore public hospitals from 2004 to 2014 (n = 67), and assigned histomolecular subtypes according to the updated 2020 WHO classification of soft tissue tumors following central pathology review and molecular profiling. RESULTS: Age-specific prevalence followed a tri-modal peak. There were significantly more embryonal and alveolar (p = 0.032) and genitourinary (non-bladder/prostate) tumors (p = 0.033) among children. Older age was associated with complete resection among spindle cell/sclerosing tumors (p = 0.027), with the omission of chemotherapy among embryonal tumors (p = 0.001), and with poorer survival among embryonal and alveolar tumors (p = 0.026, p = 0.022, respectively). Overall survival differed with stage, group, and surgical resection, adjusted for age group (p = 0.004, p = 0.001, p = 0.004, respectively). Spindle-cell/sclerosing tumors showed an indolent phenotype with a significantly lower incidence of nodal metastasis (p = 0.002), but two of 15 patients with MYOD1 mutations had a contrastingly aggressive disease. CONCLUSION: Disease and treatment response profiles of rhabdomyosarcoma subtypes vary significantly between adults and children, especially surgical resectability. In our Asian population, poorer outcomes were observed in adults with embryonal and alveolar tumors, while activating mutations influence the behavior of otherwise favorable spindle cell/sclerosing tumors.

Irreversible electroporation of the pancreas - A decade on.

Irreversible electroporation (IRE) employs the use of an electric field to cause irreversible permeability of the cell membrane, inducing apoptosis. The use of IRE for locally advanced pancreatic cancer (LAPC) was first described in 2012. The crucial advantage of IRE compared with other devices employing thermal ablation is the safety around vital structures such as vessels and ducts. This makes it an attractive option for use in the pancreas due to the close proximity of multiple major vascular structures, biliary ducts, and adjacent gastrointestinal organs. Over the past decade, IRE has established itself as a useful treatment adjunct and may soon become the standard of care, particularly for LAPC. This article will explore the current evidence and provide a concise summary of pertinent issues, including patient selection, preoperative management, clinical outcomes, radiological response and future prospects of IRE in pancreatic cancer.

Impact and the delivery of loco-regional treatment for hepatocellular carcinoma during the COVID-19 pandemic.

Hepatocellular carcinoma (HCC) is the second most lethal tumour, with therapies broadly divided into curative and palliative intent. Unfortunately, the majority of HCCs were found to be unresectable at diagnosis. Advances in novel loco-regional therapies have given patients with unresectable HCC a vital chance for disease control and survival. However, the COVID-19 pandemic has greatly shaped and impacted treatment protocols and delivery for HCC patients. This review article aims to describe the impact of the COVID-19 pandemic on the delivery of loco-regional treatment modalities for HCC and compare treatment trends between the pre -pandemic and pandemic eras. Treatment of HCC involves complex collaboration between clinical professionals within their local and global healthcare institutions. The COVID-19 pandemic has had a profound impact on the treatment of HCC. The delivery of loco-regional treatment for HCC will need to adapt to each healthcare system's unique structure.

Percutaneous Ablation of Metastatic Lymph Nodes: An Insight from the Comparison of Efficacy and Safety Between Cryoablation and Radiofrequency Ablation.

PURPOSE: To retrospectively compare efficacy and safety of computed tomography (CT)-guided percutaneous ablation of metastatic lymph nodes (LN) between cryoablation (CA) and radiofrequency ablation (RFA). MATERIALS AND METHODS: A bi-central institutional database research identified 28 patients (42 metastatic LNs) who underwent percutaneous CT-guided ablation. RFA group included 18 patients/26 tumors; CA group included 10 patients/16 tumors. Contrast-enhanced CT or MRI was used for post-ablation follow-up. Patient and tumor characteristics, technical and clinical success on a per tumor and a per patient basis and complication rates were recorded, evaluated and compared between the 2 groups. RESULTS: Both RFA and CA groups had the same median tumor size (2.00 vs. 2.20 cm, p = 0.257), the same median follow-up time (20.50 vs. 20.00 months, p = 0.923) and the same median length of hospital stay (1.00 vs. 1.00 days, p = 0.283). CA group had a higher median procedure time (110.50 vs. 52.00 min, p = 0.001). On a per lesion basis, the overall complete response post-ablation was 88.46% (23/26 lesions) in the RFA and 93.75% (15/16 lesions) in the CA group; no association was revealed between local tumor control and ablation technique (p = 0.709). No complications were recorded in both Groups. On a per patient basis, CA had a longer disease-free interval (24.00 vs. 14.50, p = 0.012) which, however, did not affect the overall survival between the two techniques (26.0 vs. 22.0, p = 0.099 for CA and RFA respectively). CONCLUSION: Our limited data suggest that CT-guided RFA and CA are equally effective on terms of efficacy and safety for the treatment of metastatic lymph nodes.

Intravascular ultrasound correlation of unenhanced magnetic resonance venography in the context of pelvic deep venous disease.

OBJECTIVE: In the present retrospective, assessor-blinded cross-sectional study, we compared the diagnostic efficacy of the relaxation-enhanced angiography without contrast and triggering (REACT) protocol for magnetic resonance venography (MRV) and intravascular ultrasound (IVUS). METHODS: All patients without prior lower limb vascular stenting who had undergone MRV with the REACT protocol and IVUS at our institution from January 2018 to May 2020 were included. The REACT protocol for MRV comprises three main phases: the adiabatic-based T2-preparation module, the non-volume-selective short tau inversion recovery pulse sequence, and the three-dimensional, modified two-point chemical-shift water-fat separated turbo-field echo pulse sequence. The IVUS findings served as the reference standard for stenosis and were used in the diagnostic efficacy analysis of the REACT protocol for MRV. The REACT protocol MRV images were reviewed by three board-certified interventional radiologists, and an interrater analysis was performed. RESULTS: A total of 33 patients (110 segments with IVUS correlation; 18 men [54.5%] and 15 women [45.5%]) were included. Most patients were Chinese (63.6%), and 24 had had bilateral deep venous disease (72.7%). The mean patient age was 59.0 years (range, 26.0-79.5 years). Moderate agreement was found between the three radiologists' diagnoses of iliac vein pathology using the REACT protocol for MRV (κ = 0.524; 95% confidence interval [CI], 0.426-0.623; P < .001). Compared with IVUS, REACT protocol MRV achieved a sensitivity of 96.10% (95% CI, 89.03%-99.19%), specificity of 78.79% (95% CI, 61.09%-91.02%), positive predictive value of 91.36% (95% CI, 84.54%-95.33%), and negative predictive value of 89.66% (95% CI, 73.81%-96.38%). Overall, 78.5% agreement was noted between the REACT protocol MRV and IVUS findings. Good agreement between the index test and reference standard was noted (κ = 0.779; 95% CI, 0.645-0.907; P ≤ .05). CONCLUSIONS: REACT protocol MRV has the potential to be a highly sensitive and specific screening tool to diagnose deep venous disease.

Trends of interventional radiology procedures during the COVID-19 pandemic: the first 27 weeks in the eye of the storm.

OBJECTIVES: While the Novel Coronavirus (COVID-19) pandemic looks to persist, institutions promote delaying procedures. Understanding trends and demands of interventional radiology (IR) procedures in the infected and COVID-free populations are needed in long-term planning. We detail IR procedure trends in the first 27 weeks of the pandemic and compare with the pre-pandemic era. METHODS: In this IRB approved retrospective electronic case review, all IR patients in our institution from 1 January to 9 July 2020, the same period in 2019 pre-pandemic and the Severe Acute Respiratory Syndrome (SARS-CoV) outbreak were included. IR procedures were classified using Interventional Radiology-Procedure Acuity Scale (IR-PAS) and category of IR procedures. Along with descriptive frequencies, the Mann-Whitney U test and Chi-square test of independence were performed. RESULTS: During the pandemic, 3655 IR procedures were performed compared to 3851 procedures pre-pandemic. No statistically significant difference in weekly IR caseloads across IR-PAS tiers between both periods (p = .088) and category of procedure (p = .054) were noted. General intervention procedures remained the largest proportion and musculoskeletal procedures the minority, in both periods. More general intervention radiology and oncology procedures were performed during the COVID-19 pandemic compared to the SARS-CoV outbreak. Thirty-four (0.93%) IR procedures were performed on 30 COVID-19 patients. There was no IR procedure-related COVID-19 cross-transmission. CONCLUSIONS: Demand for IR procedures among COVID-free patients remains high, and IR procedures involving COVID-19 represents a fraction of the IR caseload. A sustainable model in providing timely IR services to COVID-free patients needs to be considered.

Use of single-question screening for erectile dysfunction: a study of at-risk Asian men in primary health care.

This study assesses the validity of a single-question screener for erectile dysfunction (ED) in men at risk in comparison to a standard validated tool - the five-item version of the International Index of Erectile Function (IIEF-5). A total of 174 men with at least one risk factor for ED were studied, with 58.0% and 10.9% of the study respondents meeting the criteria for their erectile impairment by IIEF-5 and single-question screener respectively. Our results suggest that in spite of high feasibility, a simplified, single-question screener has low sensitivity in capturing ED prevalence, even in an at-risk population, within the Asian context.

Neuronal defects an etiological factor in congenital pelviureteric junction obstruction?

INTRODUCTION: Congenital pelviureteric junction obstruction (PUJO) is one of the most frequent causes of neonatal hydronephrosis. Obstruction at the PUJ has potential severe adverse outcomes, such as renal damage. While pyeloplasty has been established as the definitive treatment, the exact pathophysiology of congenital PUJO remains unknown. Recent research has proposed neuronal innervation defects as an etiological factor in congenital PUJO. We aim to study the expression of various neuronal markers in PUJO specimens compared with controls, and evaluate whether severity of renal disease or dysfunction pre-operatively is related to expression of neuronal markers in resected PUJO specimens. MATERIALS AND METHODS: All consecutive patients who underwent dismembered pyeloplasty at KK Women's and Children's Hospital, Singapore, for intrinsic PUJO from 2008 to 2012 were included. Patients with other co-occurring renal pathologies were excluded. Controls were obtained from nephrectomy patients with Wilm's tumor or other benign renal conditions during the same period. Specimens were stained immunohistochemically with neuronal markers protein gene product 9.5 (PGP9.5), synaptophysin, and S-100, and with CD-117, a marker for interstitial cells of Cajal (Table). Levels of expression of the markers were assessed semiquantitatively (decreased, increased or no change) in comparison with controls by two independent observers. Pre-operative data of patients' renal anatomical (ultrasonography measurements of renal pelvis size) and functional parameters (differential renal function measured using MAG-3 renal scans) were obtained. DISCUSSION: Thirty-eight PUJO specimens (38 renal units) and 20 controls were studied. Mean patient age at pyeloplasty was 25.3 months (2.9-167.6 months). Median pre-operative pelvic size was 25.0 mm (17.0-50.0 mm). Both PUJO specimens and controls showed great heterogeneity in distribution of innervation. All four immunohistochemical markers were not predictive of significant pre-operative renal pelvis dilation or pre-operative diminished renal function of the operated kidney. CONCLUSIONS: There exists marked variability in expression of neuronal markers synaptophysin, PGP9.5, and S-100, and CD-117 in PUJO specimens compared with controls. Our results show no clinical significance of the expression of neuronal markers in predicting degree of pre-operative renal pelvis dilation or differential renal function. The heterogeneity of expression of neuronal markers in PUJO specimens and controls in our population is at variance with prior studies. The etiology of PUJO is likely to be complex and multifactorial.

Undescended testis: 513 patients' characteristics, age at orchidopexy and patterns of referral.

OBJECTIVE: Undescended testis (UDT) affects 1-6% of males. Current recommendations are to correct maldescent by 1 year of age. We identify the population characteristics of children referred and managed for UDT, age at referral and orchidopexy, and patterns of referral. DESIGN, SETTING AND PATIENTS: Retrospective 5-year review of all patients operated for UDT from 2007 to 2011 in our institution. Patient demographics, neonatal diagnosis of UDT, age at referral, referral source and age at first orchidopexy were recorded. Data are reported as median (range). RESULTS: There were 513 boys with 576 undescended gonads; 450 (88%) had unilateral UDT. Congenital (present at birth) UDT was diagnosed in 287 (56%) children. Seventy-nine (15%) were premature births, 41 (8%) had associated major genitourinary abnormalities. Median age at referral was 1.1 (0-16.2) years; median age at first orchidopexy was 1.6 (0-17.2) years. When corrected for age, those with a history of prematurity and associated major genitourinary malformations were referred and operated on earlier. There was no difference in age at referral and orchidopexy when comparing unilateral versus bilateral maldescent, and palpability of UDT. Of those with congenital UDT, 70% were operated at beyond 1 year of age. Those referred from public tertiary hospitals were younger than those referred from community clinics (p<0.0001) and private healthcare institutions (p=0.003). CONCLUSIONS: Despite early diagnosis in many patients with UDT, most are referred and operated after 1 year of age, even in congenital UDT. Premature babies, those with major genitourinary anomalies, and those seen in public tertiary hospitals are referred earlier. Community health initiatives must emphasise prompt referral to allay the impact of delayed surgery.