Percutaneous Thrombectomy in Patients with Occlusions of the Aortoiliac Segment: A Case Series.

OBJECTIVE: Thrombectomy of the aortoiliac segment remains a challenge for surgical and endovascular revision. This study aimed to evaluate the concept of percutaneous thrombectomy in patients with aortoiliac segment occlusions. MATERIALS & METHODS: Eighteen patients with aortoiliac occlusion who underwent percutaneous thrombectomy were retrospectively identified using the local picture archive and divided into the stent-graft (N = 10) and native vessels (N = 8) groups. The procedure was performed by placing a 12-24 French sheath adjacent to the distal end of the occluded vessel segment. The occlusion was passed with a balloon catheter which was retracted after inflation, to deliver the thrombus into the sheath. Technical success (reperfusion of the vessel and no residual thrombus/stenosis < 30%), complications and primary arterial patency were assessed. Follow-up included computed tomography angiography and evaluation of the clinical situation via telephone. RESULTS: Technical success was achieved in 38% (7/18) of patients after percutaneous thrombectomy alone and in 100% after additional procedures. The most common complication was peripheral embolism (44%, 8/18), which was treated successfully in all cases and was linked to a mismatch between the sheath and target vessel of ≥ 1 mm (P < .01). There were no significant differences in the incidence of complications between the two groups. Primary patency was 72% (13/18) with no significant difference between groups (P = .94). Follow-up CT scans were available for 13/18 patients (72%), with a mean follow-up time of 270 ± 146 days. All patients were contacted via phone (follow-up time, 653 ± 264 days). CONCLUSION: Percutaneous thrombectomy appears to be effective for revascularization of the aortoiliac segment, both in stent-grafts and in native vessels. The most common complication is peripheral embolism; however, the risk may be reduced by choosing an adequate sheath size.

Five-year outcomes of the Bi- versus Trimodular EndurantTM stent-graft in 100 patients with infrarenal abdominal aortic repair.

BACKGROUND: Recent studies on the Endurant™ endografts mainly compared outcomes of the bimodular stent-graft to other manufacturer's endografts or reported results for cases outside manufacturer's instructions for use (IFU), while data on the experience of standard endovascular aortic repair (EVAR) of infrarenal abdominal aortic aneurysms (AAA) inside manufacturer's IFU comparing the bi- with the trimodular device is limited. METHODS: Inclusion criteria were: 1) infrarenal aneurysms (>50 mm diameter) treated by EndurantTM II (END II) or EndurantTM IIs (END IIs) stent-graft inside manufacturer's IFU; 2) available CTA with 1 mm reconstruction of the entire aorta prior to intervention. Endpoints comparing the devices included technical success, 30-day mortality, rate of complications (bleeding with conversion to open repair, stent-graft stenosis/occlusion, acute distal embolism, infection or postprocedural necessity of dialysis), endoleaks and reinterventions (5-year follow-up). Aneurysm sac diameters were compared between baseline preinterventional CTA and last post-interventional CTA. RESULTS: One hundred patients (90% male, mean age 74 years) treated with END II (N.=66) or END IIs (N.=34) were included. Technical success was 99%. One procedure-related active bleeding occurred ending up in surgical conversion (END II N.=1). 30d mortality was 0%. No initial type I/III endoleaks were present. Re-interventions were required in 19/100 (19%) of patients (END II N.=10; END IIs N.=9, P=0.17). The outcome of EVAR including technical success, 30d mortality, rate of complications, endoleaks and re-interventions showed no significant differences comparing END II/IIs. CONCLUSIONS: Five-year outcomes of EVAR show consistently safe and effective results for either END II or IIs device.

Radiation-Free Thoracic Endovascular Aneurysm Repair with Fiberoptic and Electromagnetic Guidance: A Phantom Study.

PURPOSE: To evaluate the feasibility and accuracy of a radiation-free implantation of a thoracic aortic stent graft employing fiberoptic and electromagnetic tracking in an anthropomorphic phantom. MATERIALS AND METHODS: An anthropomorphic phantom was manufactured based on computed tomography (CT) angiography data from a patient. An aortic stent graft application system was equipped with a fiber Bragg gratings and 3 electromagnetic sensors. The stent graft was navigated in the phantom by 3 interventionalists using the tracking data generated by both technologies. One implantation procedure was performed. The technical success of the procedure was evaluated using digital subtraction angiography and CT angiography (before and after the intervention). Tracking accuracy was determined at various anatomical landmarks based on separately acquired fluoroscopic images. The mean/maximum errors were measured for the stent graft application system and the tip/end of the stent graft. RESULTS: The procedure resulted in technical success with a mean error below 3 mm for the entire application system and <2 mm for the position of the tip of the stent graft. Navigation/implantation and handling of the device were rated sufficiently accurate and on par with comparable, routinely used stent graft application systems. CONCLUSIONS: The study demonstrates successful stent graft implantation during a thoracic endovascular aortic repair procedure employing advanced guidance techniques and avoiding fluoroscopic imaging. This is an essential step in facilitating the implantation of stent grafts and reducing the health risks associated with ionizing radiation during endovascular procedures.

Automated segmentation and quantification of the healthy and diseased aorta in CT angiographies using a dedicated deep learning approach.

OBJECTIVES: To develop and validate a deep learning-based algorithm for segmenting and quantifying the physiological and diseased aorta in computed tomography angiographies. METHODS: CTA exams of the aorta of 191 patients (68.1 ± 14 years, 128 male), performed between 2015 and 2018, were retrospectively identified from our imaging archive and manually segmented by two investigators. A 3D U-Net model was trained on the data, which was divided into a training, a validation, and a test group at a ratio of 7:1:2. Cases in the test group (n = 41) were evaluated to compare manual and automatic segmentations. Dice similarity coefficient (DSC), mean surface distance (MSD), and Hausdorff surface distance (HSD) were extracted. Maximum diameter, effective diameter, and area were quantified and compared between both segmentations at eight anatomical landmarks, and at the maximum area of an aneurysms if present (n = 14). Statistics included error calculation, intraclass correlation coefficient, and Bland-Altman analysis. RESULTS: A DSC of 0.95 [0.94; 0.95] and an MSD of 0.76 [0.06; 0.99] indicated close agreement between segmentations. HSD was 8.00 [4.47; 10.00]. The largest absolute errors were found in the ascending aorta with 0.8 ± 1.5 mm for maximum diameter and at the coeliac trunk with - 30.0 ± 81.6 mm2 for area. Results for absolute errors in aneurysms were - 0.5 ± 2.3 mm for maximum diameter, 0.3 ± 1.6 mm for effective diameter, and 64.9 ± 114.9 mm2 for area. ICC showed excellent agreement (> 0.9; p < 0.05) between quantitative measurements. CONCLUSIONS: Automated segmentation of the aorta on CTA data using a deep learning algorithm is feasible and allows for accurate quantification of the aortic lumen even if the vascular architecture is altered by disease. KEY POINTS: • A deep learning-based algorithm can automatically segment the aorta, mostly within acceptable margins of error, even if the vascular architecture is altered by disease. • Quantifications performed in the segmentations were mostly within clinically acceptable limits, even in pathologically altered segments of the aorta.

Retrograde Revascularization of Tibial Arteries in Patients with Critical Limb Ischemia: Plantar-Arch Versus Transpedal Approach.

PURPOSE: To compare retrograde plantar-arch and transpedal-access approach for revascularization of below-the-knee (BTK) arteries in patients with critical limb ischemia (CLI) after a failed antegrade approach. MATERIALS AND METHODS: Retrospectively we identified 811 patients who underwent BTK revascularization between 1/2014 and 1/2020. In 115/811 patients (14.2%), antegrade revascularization of at least 1 tibial artery had failed. In 67/115 (58.3%), patients retrograde access to the target vessel was achieved via the femoral access and the plantar-arch (PLANTAR-group); and in 48/115 patients (41.7%) retrograde revascularization was performed by an additional retrograde puncture (TRANSPEDAL-group). Comorbidities, presence of calcification at pedal-plantar-loop/transpedal-access-site, and tibial-target-lesion was recorded. Endpoints were technical success (PLANTAR-group: crossing the plantar-arch; TRANSPEDAL-group: intravascular placement of the pedal access sheath), procedural success [residual stenosis <30% after plain old balloon angioplasty (POBA)], and procedural complications limb salvage and survival. Correlations between calcification at access site/tibial-target-lesion and technical/procedural-success were tested. RESULTS: Technical success was achieved in 50/67 (75%) patients of the PLANTAR-group and in 39/48 (81%) patients of the TRANSPEDAL-group (p=0.1). Procedural success was obtained in 23/67 (34%) patients of the PLANTAR-group and in 25/48 (52%) patients of the TRANSPEDAL-group (p=0.04). In 14/49 (29%) cases with calcification at the pedal-plantar loop, technical success was not achieved (p=0.04), and in 33/44 (75%) patients with calcification at the tibial-target-lesion, procedural success was not attained (PLANTAR-group) (p=0.026). In the TRANSPEDAL-group, correlations between calcification at access site/tibial-target-lesion and technical/procedural-success were not observed (p=0.2/p=0.4). In the PLANTAR-group, minor complications occurred in 13/67 (19%) and in the TRANSPEDAL-group in 4/48 patients (8%) (p=0.08). Limb salvage at 12 (18) months was 90% (82%) (PLANTAR-group; 95%CI 15.771-18.061) and 84% (76%) (TRANSPEDAL-group; 95%CI 14.475-17.823) (Log-rank p=0.46). Survival at 12 (18) months was 94% (86%) (PLANTAR-group; 95%CI 16.642-18.337) and 85% (77%) (TRANSPEDAL; 95%CI 14.296-17.621) (Log-rank p=0.098). CONCLUSION: Procedural success was significantly higher using the transpedal-access approach. Calcifications at pedal-plantar loop and target-lesion significantly influenced technical/procedural failure using the plantar-arch approach. No significant difference between both retrograde techniques in terms of feasibility, safety, and limb salvage/survival was found.

Heating of an Aortic Stent for Coarctation Treatment During Magnetic Particle Imaging and Magnetic Resonance Imaging-A Comparative In Vitro Study.

PURPOSE: To evaluate heating of a redilatable stent for the treatment of aortic coarctation in neonates and small children in the new imaging modality magnetic particle imaging and established magnetic resonance imaging. MATERIALS AND METHODS: The cobalt-chromium stent (BabyStent, OSYPKA AG, Rheinfelden, Germany) has a stent design which allows for redilatation and adjustment of the diameter from 6 to 16 mm for a use in aortic coarctation. The stent loses its radial integrity while opening at predetermined breaking points at a diameter of 14 mm or 16 mm, respectively. We measured the temperature increase in the stent at different diameters during 7-min magnetic particle imaging and magnetic resonance imaging scans with fiber optic thermometers under static conditions surrounded by air. In magnetic particle imaging, stents with diameters from 6 to 16 mm were tested while in magnetic resonance imaging only stents with diameters of 6 mm and 14 mm were investigated exemplarily. RESULT: In magnetic particle imaging, the measured temperature differences increased up to 4.7 K with growing diameters, whereas the opened stents with discontinuous struts at 14 and 16 mm showed only minimal heating of max. 0.5 K. In contrast to magnetic particle imaging, our measurements showed no heating of the stents during magnetic resonance imaging under identical conditions. CONCLUSION: The BabyStent did show only slight heating in magnetic particle imaging and no detectable temperature increase in magnetic resonance imaging.

Mechanical rotational thrombectomy in long femoropopliteal artery and bypass occlusions: risk factors for periprocedural peripheral embolization.

PURPOSE: We aimed to examine lesion characteristics influencing technical outcome and periprocedural peripheral embolization (PPE) during percutaneous mechanical rotational thrombectomy (PMT) of long femoropopliteal artery and bypass occlusions. METHODS: Retrospectively, 65 consecutive patients (43 male patients, mean age 70±12 years; Rutherford category I-III), undergoing PMT (Rotarex®, Straub Medical AG) with acutely/subacutely occluded femoropopliteal arteries/bypasses were included. Occlusions (mean length, 217±98 mm) were treated by PMT followed by percutaneous transluminal angioplasty (PTA) plus drug-coated balloon or PTA plus stenting/stentgrafting. Technical success was defined as residual stenosis <30%. Follow-up included duplex ultrasound and ankle-brachial index (ABI) after 12 months. Endpoints were technical success, complications, improvement of Rutherford category, ABI, and patency (re-stenosis <50%). The influence of lesion length, duration, and thrombus density (measured in preinterventional computed tomography angiography) on technical success and PPE was analyzed. RESULTS: Technical success was 18% (12/65) after PMT alone, 92% (60/65) after additional means. Four patients (6%) underwent bypass surgery and one patient (2%) amputation. PPE occurred in 11% (7/65). During the 12-month follow-up, three patients (5%) were lost to follow-up. ABI increased from baseline 0.5±0.12 to 0.81±0.14 (p = 0.001) and Rutherford category increased by at least one level in 57 patients at 12-month follow-up (clinical success, 88%). At 12 months, primary patency was 57.4% (95% CI, 45.8%-68.9%) and secondary patency was 75.0% (95% CI, 59.8%-72.3%). As risk factors for PPE, we identified lesion length >200 mm (15%; 6/39; OR 4.5; 95% CI, 0.5-40; p = 0.014) and thrombus density ≤45 HU (20%; 2/10; OR 3.0; 95% CI, 0.2-38.9; p = 0.05). No significant relation between risk factors and technical success was found. CONCLUSION: PMT followed by PTA or implantation of stent (grafts) appears to be effective and safe for revascularization of acute/subacute long occlusions. Thrombus density <45 HU and lesion length above 20 cm represent risk factors for PPE during PMT.

Magnetic Particle Imaging: In vitro Signal Analysis and Lumen Quantification of 21 Endovascular Stents.

PURPOSE: Endovascular stents are medical devices, which are implanted in stenosed blood vessels to ensure sufficient blood flow. Due to a high rate of in-stent re-stenoses, there is the need of a noninvasive imaging method for the early detection of stent occlusion. The evaluation of the stent lumen with computed tomography (CT) and magnetic resonance imaging (MRI) is limited by material-induced artifacts. The purpose of this work is to investigate the potential of the tracer-based modality magnetic particle imaging (MPI) for stent lumen visualization and quantification. METHODS: In this in vitro study, 21 endovascular stents were investigated in a preclinical MPI scanner. Therefore, the stents were implanted in vessel phantoms. For the signal analysis, the phantoms were scanned without tracer material, and the signal-to-noise-ratio was analyzed. For the evaluation of potential artifacts and the lumen quantification, the phantoms were filled with diluted tracer agent. To calculate the stent lumen diameter a calibrated threshold value was applied. RESULTS: We can show that it is possible to visualize the lumen of a variety of endovascular stents without material induced artifacts, as the stents do not generate sufficient signals in MPI. The stent lumen quantification showed a direct correlation between the calculated and nominal diameter (r = 0.98). CONCLUSION: In contrast to MRI and CT, MPI is able to visualize and quantify stent lumina very accurately.

Accuracy evaluation of patient-specific 3D-printed aortic anatomy.

INTRODUCTION: 3D printing has a wide range of applications in medicine. In surgery, this technique can be used for preoperative planning of complex procedures, production of patient specific implants, as well as training. However, accuracy evaluations of 3D vascular models are rare. OBJECTIVES: Aim of this study was to investigate the accuracy of patient-specific 3D-printed aortic anatomies. METHODS: Patients suffering from aorto-iliac aneurysms and with indication for treatment were selected on the basis of different anatomy and localization of the aneurysm in the period from January 1st 2014 to May 27th 2016. Six patients with aorto-iliac aneurysms were selected out of the database for 3D-printing. Subsequently, computed tomography (CT) images of the printed 3D-models were compared with the original CT data sets. RESULTS: The mean deviation of the six 3D-vascular models ranged between -0.73 mm and 0.14 mm compared to the original CT-data. The relative deviation of the measured values showed no significant difference between the 3D-vascular and the original patient CT-data. CONCLUSION: Our results showed that 3D printing has the potential to produce patient-specific 3D vascular models with reliable accuracy. This enables the use of such models for the development of new endovascular procedures and devices.

Post-dilatation of an interwoven nitinol stent using a paclitaxel-coated balloon for revascularization of complex femoro-popliteal lesions.

To evaluate technical success, safety and efficacy of post-dilatation of an interwoven nitinol stent using a paclitaxel-coated balloon (PCB) for revascularization of complex femoro-popliteal lesions. Thirty patients (26 male, mean age 70 ± 7 years) suffering from peripheral artery disease (PAD) (Rutherford category II-III) underwent revascularization of chronic total occlusions (n = 22, 73%) or severe stenosis (n = 8, 27%) of the femoro-popliteal segment. Mean lesion length was 251 ± 85 mm. Lesions were treated by pre-dilatation (POBA), implantation of a helical interwoven stent and post-dilatation with a PCB. Technical success was defined as residual stenosis < 30%. Follow-up included clinical visits, duplex ultrasound and ABI at 6 and 12 months. Endpoints were patency (re-stenosis < 50%), complications, improvement of Rutherford category and ABI. Regarding patency two sub-groups were compared: long-("LL"; < 25 cm, n = 12, mean 175 ± 38 mm) and ultra-long lesions ("ULL"; ≥ 25 cm, n = 13, mean 322 ± 43 mm). Technical success was 100%. In 1/30 patients (3.3%), a minor complication occurred (embolism). The overall primary and secondary patency rates at 12 months were 80.0% (95% CI 72.5-96.9%) and 92.0% (95% CI 84.7-100%). In the LL-sub-group, primary patency was 100%, and in the ULL-sub-group, primary patency was 61.5% (95% CI 51.8-92.3%) (p = 0.056), and secondary patency 84.6% (95% CI 71.3-100%), respectively. Rutherford category increased by at least one category in 92% of patients, ABI increased from 0.52 ± 0.13 (baseline) to 0.9 ± 0.14 (12 months) (p = 0.001). Five patients underwent target lesion revascularization during follow-up (bypass: n = 1, endovascular: n = 4). No death was observed during follow-up. Post-dilatation of an interwoven nitinol stent using a paclitaxel-coated-balloon proved to be safe and effective with promising outcomes in long- and ultra-long lesions up to 12 months of follow-up.

Patient-Reported Nonadherence with Glaucoma Therapy.

Purpose: Effective glaucoma therapy relies to a great extent on the patients' ability to regularly self-administer eye drops. This study aimed to assess self-reported nonadherence and to identify potential barriers to adherence in glaucoma patients. Methods: Participants completed a 16-item questionnaire, designed to examine nonadherence rate and assess the therapy experience. Inclusion criteria stipulated treatment duration of at least 1 year. Nonadherence was defined as missing ≥5% of the prescribed pressure-lowering eye drops doses. Results: In total, 201 glaucoma patients aged 24-88 years were included. Mean treatment duration was 9.4 years. Nonadherence was reported by 30.3% of participants and 69.7% were reported to be adherent. Individuals who experienced side effects reported higher levels of nonadherence than those who did not (37.6% vs. 18.4%; P = 0.004). Eye drops with preservatives were used by 84.1% of participants, 11.9% were on combined preservative and preservative-free treatment, and 4.0% on preservative-free medication only. Self-reported nonadherence levels were 32.0%, 25.0%, and 12.5%, respectively, for each of these groups. Men reported higher rates of nonadherence than women (36.8% vs. 24.5%; P = 0.066). Age, social status, history of migration, severity of disease, and fear of blindness were not associated with significant differences in nonadherence levels. Conclusions: Nonadherence with glaucoma therapy is a significant barrier to therapeutic success for approximately one-third of patients. Nonadherence may be reduced if side effects are avoided. Preservative-free products may provide adherence benefits. The patient experience should be a key consideration when selecting appropriate treatments, to reduce nonadherence and optimize outcomes.

Comparison of the Revenue Situation in Interventional Radiology Based on the Example of Peripheral Artery Disease in the Case of a DRG Payment System and Various Internal Treatment Charges.

PURPOSE: Calculation of process-orientated costs for inpatient endovascular treatment of peripheral artery disease (PAD) from an interventional radiology (IR) perspective. Comparison of revenue situations in consideration of different ways to calculate internal treatment charges (ITCs) and diagnosis-related groups (DRG) for an independent IR department. MATERIALS AND METHODS: Costs (personnel, operating, material, and indirect costs) for endovascular treatment of PAD patients in an inpatient setting were calculated on a full cost basis. These costs were compared to the revenue situation for IR for five different scenarios: 1) IR receives the total DRG amount. IR receives the following DRG shares using ITCs based on InEK shares for 2) "Radiology" cost center type, 3) "OP" cost center type, 4) "Radiology" and "OP" cost center type, and 5) based on DKG-NT (scale of charges of the German Hospital Society). RESULTS: 78 patients (mean age: 68.6 ±â€Š11.4y) with the following DRGs were evaluated: F59A (n = 6), F59B (n = 14), F59C (n = 20) and F59 D (n = 38). The length of stay for these DRG groups was 15.8 ±â€Š12.1, 9.4 ±â€Š7.8, 2.8 ±â€Š3.7 and 3.4 ±â€Š6.5 days Material costs represented the bulk of all costs, especially if new and complex endovascular procedures were performed. Revenues for neither InEK shares nor ITCs based on DKG-NT were high enough to cover material costs. Contribution margins for the five scenarios were 1 = €â€Š1,539.29, 2 = €â€Š-1,775.31, 3 = €â€Š-2,579.41, 4 = €â€Š-963.43, 5 = €â€Š-2,687.22 in F59A, 1 = €â€Š-792.67, 2 = €â€Š-2,685.00, 3 = €â€Š-2,600.81, 4 = €â€Š-1,618.94, 5 = €â€Š-3,060.03 in F59B, 1 = €â€Š-879.87, 2 = €â€Š-2,633.14, 3 = €â€Š-3,001.07, 4 = €â€Š-1,952.33, 5 = €â€Š-3,136.24 in F59C and 1 = €â€Š703.65, 2 = €â€Š-106.35, 3 = €â€Š-773.86, 4 = €â€Š205.14, 5 = €â€Š-647.22 in F59 D. InEK shares return on average €â€Š150 - 500 more than ITCs based on the DKG-NT catalog. CONCLUSION: In this study positive contribution margins were seen only if IR receives the complete DRG amount. InEK shares do not cover incurred costs, with material costs representing the main part of treatment costs. Internal treatment charges based on the DKG-NT catalog provide the worst cost coverage. KEY POINTS: · Internal treatment charges based on the DKG-NT catalog provide the worst cost coverage for interventional radiology at our university hospital.. · Shares from the InEK matrix such as the cost center "radiology" or "OP" as revenue for IR are not sufficient to cover incurred costs. A positive contribution margin is achieved only in the case of a compensation method in which IR receives the total DRG amount.. CITATION FORMAT: · Vogt FM, Hunold P, Haegele J et al. Comparison of the Revenue Situation in Interventional Radiology Based on the Example of Peripheral Artery Disease in the Case of a DRG Payment System and Various Internal Treatment Charges. Fortschr Röntgenstr 2017; 190: 348 - 357.

Initial Experience with the E-liac® Iliac Branch Device for the Endovascular Aortic Repair of Aorto-iliac Aneurysm.

PURPOSE: Occlusion of internal iliac arteries during endovascular treatment (EVAR) of abdominal aortic (AAA) and common iliac artery aneurysms might be associated with ischemic pelvic complications. This study evaluates technical and clinical success, safety and mid-term results of a novel iliac branch device (IBD) for revascularization of the internal iliac artery (IIA) during EVAR. MATERIALS AND METHODS: Retrospectively, we identified 21 men (mean age 73.3 ± 6.2 years) treated for aorto-iliac aneurysms by use of a novel IBD (E-liac®, Jotec Hechingen, Germany). We analyzed safety (30-day survival), technical (no type I and III endoleaks, "EL"), clinical (no ischemic complications) success, mid-term patency of this IBD, peri-procedural complications, occurrence of type II ELs, rate of re-interventions and additional treatment of the revascularized IIA for landing zone preparation. RESULTS: Twenty-three IBDs were implanted. Aneurysms of the ipsilateral IIA were present in 6/23 IIAs (26.1%). Super-selective branch embolization was performed in these patients and the landing zone for the iliac sidebranch stent-graft was within the superior gluteal artery. Mean follow-up was 341 days (range 4-1103 days). Technical success and 30-day survival were 100%. Clinical success was 95.2%. Primary patency of the IBDs was 100% at 12 months. Peri-procedural complications occurred in 3/21 patients (14.3%), none of them related to the IBD. AAA-related type II ELs were found in 6 patients (28.6%), IBD-related ELs in 4/23 IBDs (17.4%) (two type Ib, two type II endoleaks). Overall re-intervention rate was 23.8%, IBD-related 8.7%. CONCLUSION: Utilization of the E-liac® IBD is safe and effective for the treatment of aorto-iliac aneurysms.

Initial experience with the E-ventus® stent-graft for endovascular treatment of visceral artery aneurysms.

BACKGROUND: To evaluate the safety and efficacy of a novel balloon-expandable stent-graft for endovascular treatment of visceral artery aneurysms (VAA). METHODS: Between 9/2014 and 1/2017 seven patients (69±15 years) with true (N.=4) and false (N.=3) VAAs were treated by implantation of balloon-expandable stent-grafts (E-ventus®, Jotec, Hechingen, Germany) using a transfemoral (N.=2) or transbrachial (N.=5) vascular access. The stent-graft was placed without prior passing of the landing zone with a sheath. In 3 of 7 patients (42.9%) additional coil or plug embolization was performed to prevent retrograde VAA perfusion. Endpoints were technical success (defined as delivery and implantation of the stent-graft in the intended position with complete exclusion of the VAA), peri-procedural complications and patency. RESULTS: Mean diameters of true VAAs (splenic artery: N.=2, common hepatic artery: N.=1, celiac trunk: N.=1) were 26±9 and of false (common hepatic artery: N.=2, gastroduodenal artery: N.=1) 29±14 mm. False aneurysms presented as emergencies with active bleeding. Technical success was 100%. One peri-procedural complication was noted: pseudoaneurysm of the accessed brachial artery. After a mean follow-up of 187 days 6/7 stent-grafts (85.7%) were patent. One patient (fVAA) died two days after the emergency procedure owing to multi-organ failure which was assessed to be non-procedure-related. Another patient (fVAA) died 7 months from the procedure owing to cancer. CONCLUSIONS: Endovascular treatment of true and false visceral artery aneurysms by use of the E-ventus® stent-graft is safe and effective. Flexibility of the stent-graft and shaft allows for implantation without passing the lesion with a sheath, enabling treatment of distal as well as complex visceral lesions. Long-term results regarding patency in a larger patient cohort are needed to confirm these findings.

Accuracy of pre-interventional computed tomography angiography post-processing software and extravascularly calibrated devices to determine vessel diameters: comparison with an intravascularly located calibrated catheter.

Background Accurate vessel sizing might affect treatment outcome of endovascular therapy. Purpose To compare accuracy of peripheral vessel diameter measurements using pre-interventional computed tomography angiography post processing software (CTA-PPS) and extravascularly located calibrated devices used during digital subtraction angiography (DSA) with an intravascular scaled catheter (SC). Material and Methods In 33 patients (28 men, mean age = 72 ± 11 years) a SC was used during DSA of the femoro-popliteal territory. Simultaneously, one scaled radiopaque tape (SRT) was affixed to the lateral thigh, one scaled radiopaque ruler (SRR) was positioned on the angiography table. For each patient, diameters of five anatomic landmarks were measured on DSA images after calibration using different scaled devices and CTA-PPS. Diameters were compared to SC (reference) and between groups of non-obese (NOB) and obese (OB) patients. Results In total, 660 measurements were performed. Compared to the reference, SRT overestimated the diameter by 1.2% (range = -10-12, standard deviation [SD] = 4.1%, intraclass correlation coefficient [ICC] = 0.992, 95% confidence interval [CI] = 0.989-0.992, P = 0.01), the SRR and CTA-PPS underestimated it by 21.3% (range = 1-47, SD = 9.4%, ICC = 0.864, 95% CI = 0.11-0.963, P = 0.08) and 3.2% (range = 17-38, SD = 9.7%, ICC = 0.976, 95% CI = 0.964-0.983, P = 0.01), respectively. Underestimation using the SRR was greatest in the proximal superficial-femoral artery (31%) and lowest at the P2 level of the popliteal artery (15%). In the NOB group, diameter overestimation of the SRT was 0.8% (range = 4-7, SD = 4.2%, B = 0.071, 95% CI = 0.293-0.435, P = 0.08) compared to the OB group of 1.6% (range = -7-4, SD = 2.9%, B = 0.010, 95% CI = 0.474-0.454, P = 0.96). Diameter underestimation of the SRR was 17.3% (range = 13-21, SD = 3.1%, B = 0.946, 95% CI = 0.486-1.405, P = 0.002) in the NOB group, 23.3% (range = 11-36, SD = 6.6%, B = 0.870, 95% CI = 0.268-1.472, P = 0.007) in the OB group. Conclusion For calibrated measurements SRT and CTA-PPS prove accurate compared to the reference, while SRR does not. Obesity has a significant impact on underestimation of diameter if SRR is used.

Reliability of the pronator quadratus fat pad sign to predict the severity of distal radius fractures.

AIM: To evaluate the reliability of pronator quadratus fat pad sign to detect distal radius fracture and to predict its severity. METHODS: Retrospectively we identified 89 consecutive patients (41 female, mean age 49 ± 18 years) who had X-ray (CR) and computed tomography (CT) within 24 h following distal forearm trauma. Thickness of pronator quadratus fat pad complex (PQC) was measured using lateral views (CR) and sagittal reconstructions (CT). Pearson's test was used to determine the correlation of the PQC thickness in CR and CT. A positive pronator quadratus sign (PQS) was defined as a PQC > 8.0 mm (female) or > 9.0 mm (male). Frykman classification was utilized to assess the severity of fractures. RESULTS: Forty-four/89 patients (49%) had a distal radius fracture (Frykman I n = 3, II n = 0, III n = 10, IV n = 5, V n = 2, VI n = 2, VII n = 9, VIII n = 13). Mean thickness of the PQC thickness can reliably be measured on X-ray views and was 7.5 ± 2.8 mm in lateral views (CR), respectively 9.4 ± 3.0 mm in sagittal reconstructions (CT), resulting in a significant correlation coefficient of 0.795. A positive PQS at CR was present in 21/44 patients (48%) with distal radius fracture and in 2/45 patients (4%) without distal radius fracture, resulting in a specificity of 96% and a sensitivity of 48% for the detection of distal radius fractures. There was no correlation between thickness of the PQC and severity of distal radius fractures. CONCLUSION: A positive PQS shows high specificity but low sensitivity for detection of distal radius fractures. The PQC thickness cannot predict the severity of distal radius fractures.

Simultaneous Antegrade-Retrograde Subintimal Revascularization of a Femoropopliteal Chronic Total Occlusion by a Reentry Device-Facilitated Puncture of a Retrogradely Inserted Balloon.

PURPOSE: To report a rendezvous technique for subintimal revascularization of a chronic total occlusion (CTO) of the superficial femoral artery (SFA). TECHNIQUE: This maneuver is appropriate after failure to cross a long SFA CTO via intra- and subintimal approaches from the ipsilateral femoral as well as retrograde posterior tibial artery (PTA) access sites. After predilation of the subintimal space from the femoral access, a reentry device was placed at the level of the first popliteal artery segment. A balloon was delivered via the retrograde PTA access and inflated at the corresponding level of the reentry device. The balloon was punctured with the needle of the reentry device under fluoroscopic control, and a 0.014-inch guidewire was placed within the punctured balloon. The balloon and the antegrade guidewire were retracted from the retrograde access while the guidewire was gently pushed from the femoral site. Conventional balloon angioplasty of the SFA occlusion was performed via the femoral access, followed by overlapping stent-graft implantation. Complete revascularization of the CTO was documented. CONCLUSION: In selected cases a transfemoral reentry device-assisted puncture of a retrogradely inserted balloon within the subintimal space may facilitate a rendezvous and revascularization if standard techniques to cross long CTOs have failed.