Digital Variance Angiography in Selective Lower Limb Interventions.

PURPOSE: To evaluate the potential benefits of digital variance angiography (DVA) in selective lower limb angiography and to compare the performance of 2 DVA algorithms (conventional DVA1 and the recently developed DVA2) to that of digital subtraction angiography (DSA). MATERIALS AND METHODS: From November 2019 to May 2020, 112 iodinated contrast media (ICM) and 40 carbon dioxide (CO2) angiograms were collected from 15 and 13 peripheral artery disease patients, respectively. The DVA files were retrospectively generated from the same unsubtracted source file as DSA. The objectively calculated contrast-to-noise ratio (CNR) and the subjective visual image quality of DSA, DVA1, and DVA2 images were statistically compared using the Wilcoxon signed-rank test. The images were evaluated by 6 radiologists (R.P.T., S.V., A.M.K., S.S.A., O.E., and J.S.) from 2 centers using a 5-grade Likert scale. RESULTS: Both DVA algorithms produced similar increase (at least 2-fold) in CNR values (P < .001) and significantly higher image quality scores than DSA, independent of the contrast agent used. The overall scores with ICM were 3.61 ± 0.05 for DSA, 4.30 ± 0.04 for DVA1, and 4.33 ± 0.04 for DVA2 (each P < .001 vs DSA). The scores for CO2 were 3.10 ± 0.14 for DSA, 3.63 ± 0.13 for DVA1 (P < .001 vs DSA), and 3.38 ± 0.13 for DVA2 (P < .05 vs DSA). CONCLUSIONS: DVA provides higher CNR and significantly better image quality in selective lower limb interventions irrespective of the contrast agent used. Between DVA algorithms, DVA1 is preferred because of its identical or better image quality than DVA2. DVA can potentially help the interventional decision process and its quality reserve might allow dose management (radiation/ICM reduction) in the future.

Are X-ray Safety Glasses Alone Enough for Adequate Ocular Protection in Complex Radiological Interventions?

ABSTRACT: The maximum annual radiation ocular dose limit for medical staff has been reduced to 20 mSv in the current European directive 2013/59/Euratom. This multi-centric study aims at reporting the protected and unprotected eye lens doses in different fluoroscopically guided interventions and to evaluate any other factors that could influence the ocular dose. From July 2018 to July 2019, ocular radiation doses of six interventionists of four departments during complex interventions were recorded with a thermoluminescent dosimeter in front of and behind radiation protection glasses to measure the protected and unprotected doses. The position of personnel, intervention type, fluoroscopy time, total body dose and use of pre-installed protection devices like lead acrylic shields were also systematically recorded. Linear regression analysis was used to estimate the doses at 2 y and 5 y. The annual unprotected/protected ocular doses of six interventionists were 67/21, 32.7/3.3, 27.4/5.1, 7/0, 21.8/2.2, and 0/0 mSv, respectively. The unprotected dose crossed the 20-mSv annual limits for four interventionists and protected dose for one less experienced interventionist. The estimated 5-y protected ocular dose of this interventionist was 101.318 mSv (95%CI 96.066-106.57), also crossing the 5-y limit. The use of a lead acrylic shield was observed to have a significant effect in reducing ocular doses. The annual unprotected and protected ocular doses for interventionists dealing with complex interventions could cross the present permitted yearly limit. The measurement of significant protected ocular dose behind the radiation protection glasses emphasizes the additional indispensable role of pre-installed radiation protection devices and training in reducing radiation doses for complex procedures.

Role of Endoluminal Techniques in the Management of Acute Type B Aortic Dissection and Intramural Haematoma.

Twenty-five years ago, optimal medical management was the mainstay of treatment in acute type B aortic dissection (TBAD) and intramural haematoma (IMH), with surgery being reserved for cases with rupture or critical branch vessel ischaemia. Less invasive endoluminal management of TBAD and IMH has developed rapidly over the past two and a half decades, thus changing the treatment algorithm in these patients. Today the focus has shifted to primary management with a combination of endoluminal intervention and optimal medical treatment. The purpose of this article is to describe the various interventional techniques, discuss the indications for intervention, and present the results in the current literature regarding clinical (rupture, branch vessel ischaemia) as well as morphological response (aortic remodelling), complications, and morbidity/mortality associated with endoluminal intervention.

Urgent Endovascular Treatment for Non-traumatic Descending Thoracic Aortic Rupture.

PURPOSE: To evaluate the efficacy of endovascular repair of non-traumatic rupture of the descending thoracic aorta. MATERIALS AND METHODS: From January 2011 to August 2017, 22 consecutive patients (16 men, mean age 73.7 years, range 63-92 years) with non-traumatic rupture of the descending thoracic aorta were treated endovascularly. Thirty-day mortality as well as procedure-related morbidity including stroke, renal, pulmonary and spinal complications were retrospectively assessed. Median follow-up was 29 months (range 6-65 months). RESULTS: Nine patients had type B dissections, and 13 had atherosclerotic aortic aneurysms. The technical success was 100%; 86.3% of patients (19/22) were treated percutaneously. Thirteen patients (59%) received a single endograft, 8 (36%) received 2 endografts, and 1 received 3 endografts. The endograft diameters ranged between 28 and 46 mm. Two dissection patients received additional distal bare metal true lumen stents. Eleven patients required additional drainage of thoracic hematoma. Three primary percutaneous sites (15.7%) required surgical revision. No spinal cord ischemic or renal complications were observed. Stroke was observed in 2 patients (9%), both with full coverage of left subclavian artery origin. Four patients (18%) required tracheostomy with prolonged respiratory support (range 10-15 days). The median intensive care unit stay was 5 days (range 1-27 days). The 30-day mortality was 18.1% (4/22). CONCLUSION: Endoluminal repair of non-traumatic rupture of the descending thoracic aorta can be performed percutaneously. It showed a 30-day mortality of 18.1%, and no spinal cord injury or renal complications were observed in surviving patients at follow-up. LEVEL OF EVIDENCE: Level 4, case series.

Will X-ray Safety Glasses Become Mandatory for Radiological Vascular Interventions?

PURPOSE: The annual permissible radiation ocular lens dose has been reduced to 20 millisieverts (mSv) in the current European directive 2013/59/Euratom. The aim of this study was to evaluate the personal radiation dose for vascular interventions with special focus on ocular lens dose. MATERIALS AND METHODS: From May 2016 to October 2016, the personal radiation doses of two interventionists and four technicians were prospectively recorded during 206 vascular interventions. The position of personnel, intervention type and fluoroscopy time were recorded. Parameters evaluated were total body dose measured by film dosimeter, hand dose measured by ring thermoluminescent dosimeter (TLD) and ocular lens dose measured by TLD placed in front of the safety glasses. Linear regression analysis was used to estimate the dose at 2 and 5 years. RESULTS: The ocular lens dose, hand and total body dose of the two interventionists were 11/5, 56/47 and 0.6 mSv each, respectively. The estimated 5-year ocular dose was 113.08 mSv (95% CI 38.2-187.97)/40.95 (95% CI 16.9-64.7). Similarly, hand dose was 608.4 mSv (95% CI 442.78-774.38)/514.47 (95% CI 329.83-699.10) and body dose 6.07 mSv (95% CI 4.70-8.22)/5.12 (95% CI 3.65-6.59), respectively. Amongst four technicians, only the first assistant showed recordings of 0.3 mSv body dose, 2 mSv ocular lens dose and 5 mSv hand dose. CONCLUSION: The yearly ocular lens dose, particularly for interventionists dealing with complex interventions, could cross the permitted yearly limit set by the new Euratom directive. Therefore, X-ray safety glasses would become mandatory for complex radiological vascular interventions. LEVEL OF EVIDENCE: Level III, non-randomized controlled cohort/follow-up study.

Retrospective Evaluation of Percutaneous Access for TEVAR and EVAR: Time to Make it the Standard Approach?

Introduction To evaluate the safety of percutaneous endovascular aortic repair and the relationship of access site characteristics to complications Materials and Methods All patients undergoing percutaneous TEVAR, EVAR and FEVAR procedures from January 2010 to May 2016 were retrospectively analysed for incidence of complications and their relationship to various access site characteristics like access artery size, degree of vessel calcification, skin to artery distance and sheath to artery ratio. Hemostasis occurring within 15 min after suture closure with or without manual compression was defined as primary hemostasis. Results 92 patients with 142 femoral access sites were included in the study. Median follow-up was 28.13 months (range 2.5 - 76.7 months, Mean 32.39, SD - 21.66 months). Introducer system size ranged from 12F to 25F. Primary haemostasis was achieved in 97.1 % (138/142) of the total femoral access sites. Four access sites (2.8 %) had to be closed surgically; in all 4 cases the introducer systems was ≥ 18F. Two of these access sites had been operated upon previously. Late complications including inguinal hematoma (n = 7), wound infection (n = 1), scrotal hematoma (n = 1), pseudoaneurysm (n = 4) and late bleeding (n = 4) occurred in 17 access sites (11.9 %), of which 13 were managed conservatively. On account of the low complication rate, no correlation between the evaluated variables and observed complications could be established. Conclusion Percutaneous endovascular aortic repair is feasible and safe irrespective of the size of the introducer sheath and the nature of aorto-iliac pathology. The technical success rate is high and the incidence of complications is low. Early complications are most often associated with sheath sizes ≥ 18 F. The majority of the late complications can be treated conservatively. Key points: · Percutaneous endovascular aortic repair is feasible and safe.. · Technical success rate is high and complication rate is low.. · Vascular closure device failure in the occasional patient may necessitate surgical intervention.. Citation Format · Thomas RP, Kowald T, Schmuck B et al. Retrospective Evaluation of Percutaneous Access for TEVAR and EVAR: Time to Make it the Standard Approach?. Fortschr Röntgenstr 2017; 189: 347 - 355.