Management of Renal Artery-Inferior Vena Cava Fistula Following Nephrectomy for Penetrating Trauma

Background: Renal artery to inferior vena cava fistula is a rare event postnephrectomy. We report a case of an adult male in whom a renal artery to inferior vena cava fistula was detected on non-invasive studies following nephrectomy for penetrating trauma. Case Report: A fistula between the right renal artery and inferior vena cava was confirmed with diagnostic angiography. The fistula was successfully embolized using microcoils. Discussion: This case highlights the importance of exploring retroperitoneal hematomas secondary to penetrating trauma.

Radiation Dose and Fluoroscopy Time of Diagnostic Angiography in Patients with Spinal Dural Arteriovenous Fistula

Purpose Spinal dural arteriovenous fistulas (SDAVFs) represent the most common indication for a spinal angiography. The diagnostic reference level (DRL) for this specific endovascular procedure is still to be determined. This single-center study provides detailed dosimetrics of diagnostic spinal angiography performed in patients with SDAVFs. Methods Retrospective analysis of all diagnostic spinal angiographies between December 2011 and January 2021. Only patients with an SDAVF who had baseline magnetic resonance angiography (MRA), diagnostic digital subtraction angiography (DSA), treatment and follow-up at this institution were included. Dose area product (DAP, Gy cm2) and fluoroscopy time were compared between preoperative and postoperative angiographies, according to SDAVF locations (common versus uncommon), MRA results at baseline (positive versus negative) and DSA protocols (low-dose, mixed-dose, normal-dose). The 75th percentile of the DAP distribution was used to define the local DRL. Results A total of 62 spinal angiographies were performed in 25 patients with SDAVF. Preoperative angiographies (30/62, 48%) yielded a significantly higher DAP and longer fluoroscopy time when compared to postoperative angiographies (32/62, 53%) (p < 0.01). The local DRL was 329.41 Gy cm2 for a nonspecific (n = 62), 395.59 Gy cm2 for a preoperative and 138.6 Gy cm2 for a postoperative spinal angiography. Preoperative angiography of uncommonly located SDAVFs yielded a significantly longer fluoroscopy time (p = 0.02). The MRA-based fistula detection had no significant impact on dosimetrics (p > 0.05). A low-dose protocol yielded a 61% reduction of DAP. Conclusion The results of the present study suggest novel DRLs for spinal angiography in patients with SDAVF. Dedicated low-dose protocols enable radiation dose optimization in these procedures.

Radiation Exposure During Diagnostic and Therapeutic Angiography of Carotid-cavernous Fistula

Purpose The aim of this study was to determine local diagnostic reference levels (DRLs) during endovascular diagnostics and therapy of carotid-cavernous fistulas (CCF). Methods In a retrospective study design, DRLs, achievable dose (AD) and mean values were assessed for all patients with CCF undergoing diagnostic angiography (I) or embolization (II). All procedures were performed with the flat-panel angiography system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the type of CCF and the type of procedure. Results In total, 86 neurointerventional procedures of 48 patients with CCF were executed between February 2010 and July 2021. The following DRLs, AD and mean values could be determined: (I) DRL 215 Gy ∙ cm2, AD 169 Gy ∙ cm2, mean 165 Gy ∙ cm2; (II) DRL 350 Gy ∙ cm2, AD 226 Gy ∙ cm2, mean 266 Gy ∙ cm2. Dose levels of embolization were significantly higher compared to diagnostic angiography (p < 0.001). No significant dose difference was observed with respect to the type of fistula or the embolization method. Conclusion This article reports on diagnostic and therapeutic DRLs in the management of CCF that could serve as a benchmark for the national radiation protection authorities. Differentiation by fistula type or embolization method does not seem to be useful.

Digital variance angiography allows about 70% decrease of DSA-related radiation exposure in lower limb X-ray angiography

Our aim was to investigate whether the previously observed higher contrast-to-noise ratio (CNR) and better image quality of Digital Variance Angiography (DVA) - compared to Digital Subtraction Angiography (DSA) - can be used to reduce radiation exposure in lower limb X-ray angiography. This prospective study enrolled 30 peripheral artery disease patients (mean ± SD age 70 ± 8 years) undergoing diagnostic angiography. In all patients, both normal (1.2 µGy/frame; 100%) and low-dose (0.36 µGy/frame; 30%) protocols were used for the acquisition of images in three anatomical regions (abdominal, femoral, crural). The CNR of DSA and DVA images were calculated, and the visual quality was evaluated by seven specialists using a 5-grade Likert scale. For investigating non-inferiority, the difference of low-dose DVA and normal dose DSA scores (DVA30-DSA100) was analyzed. DVA produced two- to three-fold CNR and significantly higher visual score than DSA. DVA30 proved to be superior to DSA100 in the crural region (difference 0.25 ± 0.07, p < 0.001), and there was no significant difference in the femoral (− 0.08 ± 0.06, p = 0.435) and abdominal (− 0.10 ± 0.09, p = 0.350) regions. Our data show that DVA allows about 70% reduction of DSA-related radiation exposure in lower limb X-ray angiography, providing a potential new radiation protection tool for the patients and the medical staff.

Abstract 1122‐000160: Transvenous Embolization Technique: A Modern Strategy for Anterior Ethmoidal Dural Arteriovenous Fistulas

Introduction : Ethmoidal dural arteriovenous fistulae (AVF) are rare intracranial lesions and account for 2–3% of all dAVF. They are often supplied by the ethmoidal or falcine branches of the ophthalmic artery and typically drain into a cortical vein then into the superior sagittal sinus (SSS). Current available treatment options include surgical resection and endovascular embolization via transarterial and transvenous routes. Prior studies have solely compared surgical and transarterial endovascular treatment approaches. Reports of the transvenous approach remain scarce in the literature. Methods : We performed a retrospective review for anterior ethmoidal (AE)‐dAVFs treated with transvenous embolization by our practice between August 2018 and August 2021. Four patients with 5 dAVFs were identified. We describe the presentation, treatment, and outcome of these cases. Results : We describe four patients with AE‐dAVF. Case 1 is a 33‐year‐old man with a previously treated basal ganglia arteriovenous malformation achieving cure. He was lost for follow up for three years and returned with symptoms of peri‐orbital headache and blurry vision. Diagnostic angiography revealed a dAVF arising from the cribriform plate with arterial supply derived from bilateral AE arteries and venous drainage via a common cortical frontal interhemispheric vein to the anterior third of the SSS. Transvenous embolization was achieved and liquid embolic was injected into the vein with retrograde penetration to the fistulous point. Follow‐up angiography revealed obliteration of the dAVF. Case 2 is a 23‐year‐old man with chronic headache who was found to have a right sided ethmoidal dAVF arising from the right ophthalmic artery for which he underwent successful embolization through a transarterial approach. Follow‐up angiography demonstrated occlusion of the treated fistula and new left sided ethmoidal AVF arising from the left ophthalmic artery with a single draining cerebral vein which drains into the anterior third of the SSS. Transvenous embolization was achieved via coiling. Follow up angiography also showed complete occlusion of the dAVF. Case 3 was a 67‐year‐old woman who presented with a Cognard type III right ethmoidal dAVF with arterial feeders through surpra‐orbital branches of the right ophthalmic artery, draining into a frontal cortical vein leading to the SSS. The patient underwent transvenous embolization using coils. Case 4 was a 64‐year‐old woman who presented with scalp tenderness. Diagnostic angiography revealed a left AE‐dAVF. Transvenous embolization with complete occlusion was achieved using a combination of liquid embolic and coil embolization. No adverse events were encountered during or after embolization, but long‐term outcome has yet to be collected for cases 3 and 4. There were no neurologic procedural complications. Conclusions : This small case series shows that transvenous embolization is a feasible, effective, and safe alternative to surgery. Larger prospective studies are needed to further validate this treatment approach in patients with ethmoidal dAVF.

Current Approach to Planning Angiography and MAA Administration

Transarterial radioembolization of primary and secondary hepatic malignancies utilizing yttrium-90 microspheres is a commonly performed treatment by interventional radiologists. Traditionally performed as a two-part procedure, a diagnostic angiography is performed 1 to 3 weeks prior to treatment with the injection of technetium-99m-macroaggregated albumin followed by planar scintigraphy in the nuclear medicine department. Careful attention must be paid to the details during the diagnostic angiography to ensure the delivery of a safe and optimal dose to the diseased liver and to minimize radiation-induced damage to both unaffected liver and adjacent structures. In this article, we will review the steps and considerations that must be made during the angiography planning and discuss current and future areas of research.

Radiation exposure in the endovascular therapy of cranial and spinal dural arteriovenous fistula in the last decade: a retrospective, single-center observational study

Purpose This study aims to determine local diagnostic reference levels (DRLs) in the endovascular therapy (EVT) of patients with cranial and spinal dural arteriovenous fistula (dAVF). Methods In a retrospective study design, DRLs and achievable dose (AD) were assessed for all patients with cranial and spinal dAVF undergoing EVT (I) or diagnostic angiography (II). All procedures were performed at the flat-panel angiography-system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the region of fistula and the type of procedure. Results In total, 264 neurointerventional procedures of 131 patients with dAVF (94 cranial, 37 spinal) were executed between 02/2010 and 12/2020. The following DRLs, AD, and mean values could be determined: for cranial dAVF (I) DRL 507.33 Gy cm2, AD 369.79 Gy cm2, mean 396.51 Gy cm2; (II) DRL 256.65 Gy cm2, AD 214.19 Gy cm2, mean 211.80 Gy cm2; for spinal dAVF (I) DRL 482.72 Gy cm2, AD 275.98 Gy cm2, mean 347.12 Gy cm2; (II) DRL 396.39 Gy cm2, AD 210.57 Gy cm2, mean 299.55 Gy cm2. Dose levels of EVT were significantly higher compared to diagnostic angiographies (p < 0.001). No statistical difference in dose levels regarding the localization of dAVF was found. Conclusion Our results could be used for establishing DRLs in the EVT of cranial and spinal dAVF. Because radiation exposure to comparably complex interventions such as AVM embolization is similar, it may be useful to determine general DRLs for both entities together.

True Mycotic Aneurysms: A Report of Three Patients with Internal Carotid Artery Aneurysm and Mucormycosis, and Literature Review

Background Aneurysm formation of internal carotid arteries (ICA) in patients with mucormycosis is a scarce phenomenon. However, the prevalence of rhino-cerebral mucormycosis has been reported to increase after the coronavirus disease 2019 (COVID-19) pandemic. Methods Three patients with stroke and subarachnoid hemorrhage due to ICA aneurysm after the involvement of adjacent paranasal sinuses with mucormycosis were presented. All patients were recruited from Namazi and Khalili hospitals affiliated with Shiraz University of Medical Sciences in Iran from April 2021 to May 2021. Results They had a history of diabetes and corticosteroid use. Also, one of them was treated with imatinib. Two out of three patients were infected with SARS-CoV-2 infection before developing mucormycosis. Two patients had diagnostic angiography before endovascular intervention. One patient did not undergo any therapeutic intervention due to total artery occlusion, whereas the other patient experienced a successful parent artery occlusion by coiling, and only this patient survived. Although all patients received antifungal treatment and surgical debridement, two of them died. Conclusions In the patients with rhino-cerebral mucormycosis evolving of aneurysm should be promptly and meticulously investigated by magnetic resonance angiography (MRA) and computed tomography angiography (CTA). As this type of aneurysms was very fast-growing, as soon as the involvement of sphenoid sinus was detected, the possibility of ICA aneurysm formation should always be kept in mind. If the patient developed an aneurysm, prompt intensive antifungal therapy and therapeutic endovascular interventions such as stenting, coiling, or sacrificing should be considered as soon as possible to optimize outcomes.

Intracoronary acetylcholine testing among 746 consecutive Japanese patients with angina-like chest pain and unobstructed coronary artery disease

Background Intracoronary acetylcholine (ACh) testing is useful for the detection of epicardial spasm (ES) and coronary microvascular spasm (CMS). Objectives We retrospectively analysed the incidence of ES and CMS in consecutive Japanese patients with unobstructed coronary artery disease. Methods From January 1991 to February 2019, we performed intracoronary ACh testing of 1864 patients. Among these patients, a total of 746 consecutive patients (254 women, mean age 64±11 years) who underwent first diagnostic angiography for suspected myocardial ischaemia and had unobstructed coronary arteries (&lt; 50%) were enrolled. ES was defined as ≥ 90% stenosis and usual chest symptoms and ischaemic ECG changes, while CMS was defined as &lt; 75% stenosis and usual chest symptoms and ischaemic ECG changes. Results We performed intracoronary ACh testing on both coronary arteries in 96% (716/746) of all subjects. Overall, ES was found in 329 patients (44%), whereas CMS was revealed in 40 patients (5%) including 4 patients with coexisting ES. In patients with ES, women made up 22%, and approximately three-quarters of the patients had resting chest pain. In contrast, women composed 65% (26/40) of those with CMS, and 15 patients with CMS had another chest symptom. CMS was frequently observed in the LCA but not the RCA. Electrical cardioversion was necessary for two patients. Conclusions CMS was recognized in only 5% of consecutive Japanese patients with unobstructed coronary artery disease, whereas ES was revealed in 44% of those patients. CMS was often observed in women and in the LCA.

Angioplasty of Flow‐Limiting Stenosis Reduces Aortic and Brachial Blood Pressure in Patients With Peripheral Artery Disease

Background Arterial hypertension affects cardiovascular outcome in patients with peripheral artery disease (PAD). We hypothesized that angioplasty of peripheral arterial stenoses decreases aortic (aBP) and brachial blood pressure (bBP). Methods and Results In an index cohort (n=30), we simultaneously measured aBP, bBP, augmentation index (AIx), and aortic pulse wave velocity (PWV) before and after angioplasty of the iliac and femoropopliteal arteries; diagnostic angiography served as a control. In an all‐comer registry cohort (n=381), we prospectively measured bBP in patients scheduled for angioplasty of the iliac, femoral, and crural arteries or diagnostic angiography. Systolic aBP decreased after iliac (Δ−25 mmHg; 95% CI, −30 to −20; P <0.0001) and femoropopliteal angioplasty (Δ−12 mmHg; 95% CI, −17 to −5; P <0.0001) as compared with diagnostic angiography. Diastolic aBP decreased after iliac (Δ−9 mmHg; 95% CI, −13 to −1; P =0.01) but not femoropopliteal angioplasty. In parallel, AIx significantly dropped, whereas PWV remained stable. In the registry cohort, systolic bBP decreased after angioplasty of the iliac (Δ−17 mmHg; 95% CI, −31 to −8; P =0.0005) and femoropopliteal arteries (Δ−10 mmHg; 95% CI, −23 to −1; P =0.04) but not the crural arteries, as compared with diagnostic angiography. Diastolic bBP decreased after iliac (Δ−10 mmHg; 95% CI, −17 to −2; P =0.01) and femoropopliteal angioplasty (Δ−9 mmHg; 95% CI, −15 to −1; P =0.04). Multivariate analysis identified baseline systolic bBP and site of lesion as determinants of systolic bBP drop after endovascular treatment. Conclusions Angioplasty of flow‐limiting stenoses in patients with peripheral artery disease lowers aortic and brachial blood pressure with more pronounced effects at more proximal lesion sites and elevated baseline systolic blood pressure. These data indicate a role of endovascular treatment to acutely optimize blood pressure in patients with peripheral artery disease. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT02728479.