[Recommendations for the specialist further training of nursing personnel on intensive care units in the treatment of abdominal aortic aneurysms: results of a modified Delphi procedure with experts]. / Empfehlungen zur Fachweiterbildung von Pflegefachpersonen der Intensivstation bei der Behandlung des Bauchaortenaneurysmas: Ergebnisse eines modifizierten Delphi-Verfahrens mit Expert:innen.

INTRODUCTION: The medical development in the previous 15 years and the changes in treatment reality of the comprehensive elective treatment of abdominal aortic aneurysms necessitate a re-evaluation of the quality assurance guidelines of the Federal Joint Committee in Germany (QBAA-RL). In the current version this requires a specialist further training quota for nursing personnel in intensive care wards of 50%. The quota was determined in 2008 based on expert opinions, although a direct empirical evidence base for this does not exist. METHODS: Representatives from the fields of patient representation, physicians, nursing personnel and other relevant interface areas were invited to participate in a modified Delphi procedure. Following a comprehensive narrative literature search, a survey and focus group discussions with national and international experts, a total of three anonymized online-based voting rounds were carried out for which previously determined key statements were assessed with a 4­point Likert scale (totally disagree up to totally agree). In addition, the expert panel had also defined a recommendation for a minimum quota for the specialist training of nursing personnel on intensive care wards in the treatment of abdominal aortic aneurysms, whereby an a priori agreement of 80% of the participants was defined as the consensus limit. RESULTS: Overall, 37 experts participated in the discussions and three successive voting rounds (participation rate 89%). The panel confirmed the necessity of a re-evaluation of the guideline recommendations and recommended the introduction of a shift-related minimum quota of 30% of the full-time equivalent of nursing personnel on intensive care wards and the introduction of structured promotional programs for long-term elevation of the quota. CONCLUSION: In this national Delphi procedure with medical and nursing experts as well as representatives of patients, the fundamental benefits and needs of professional specialist qualifications in the field of intensive care medicine were confirmed. The corresponding minimum quota for specialist further training of intensive care nursing personnel should generally apply without limitations to specific groups. The expert panel stipulates a shift-related minimum quota for intensive care nursing personnel with specialist training of 30% of the nursing personnel on intensive care wards and the obligatory introduction of structured and transparent promotion programs for the long-term enhancement.

Intraoperative Extravascular Ultrasound in the Identification of Flow-Limiting Dissections after Balloon Angioplasty in the Femoropopliteal Segment.

Background: The BIO REACT study is designed to investigate the incremental value of Extravascular UltraSound (EVUS) added to conventional angiography, compared to conventional angiography only for the identification of Flow-Limiting Dissections (FLD) and to evaluate the safety and efficacy of the REsponse Adapted Combination Therapy (REACT) for the treatment of femoropopliteal lesions. Methods: The primary endpoints were the specificity and sensitivity of EVUS added to angiography for the detection of FLD. Secondary endpoints were primary patency of the REACT therapy within 12 months, fCD-TLR, freedom from MAE, major target limb amputations (mTLA) and survival rates within 24 months. Results: A total of 150 patients were included. EVUS added to angiography had an overall sensitivity of 29% and specificity of 93% for the detection of FLD. There was no PSVR cut-off offering a clinically acceptable trade-off between meaningful sensitivity and specificity values for the detection of FLD. At 12 months, treatment with the REACT resulted in primary patency and fCD-TLR of 81.6% and 94.3%, respectively. In addition, freedom from MAE was 94.3% at 12 months. At 24 months, the survival rate was 94.0%. No mTLA was reported up to the 24-month follow-up. Conclusions: The addition of DUS to angiography showed limited value for detecting FLD in femoropopliteal artery disease.

Danger Zones of the Gluteal Anatomy: Improving the Safety Profile of the Gluteal Fat Grafting.

INTRODUCTION: Knowledge of the vascular anatomy is critical to performing safe gluteal surgery. To date, only the course of the main blood vessels within the muscles has been outlined. These findings are based on MRI and CTA images that do not conform to a topographically standardized and normalized probability distribution. OBJECTIVES: The aim of this study was to develop a three-dimensional mapping of the gluteal zones of high vascular density in relation to anatomical landmarks. MATERIALS AND METHODS: This single-center retrospective cohort analysis comprised all consecutive patients who underwent cone-beam computed tomography (CBCT) scans between January 2016 and October 2021. The location of blood vessels in the gluteal region was allometrically normalized in relation to anatomical landmarks. Moreover, the caliber and area of the blood vessels were assessed. RESULTS: CBCT scans of 32 patients with an average age of 64 ± 12 years (range 34-87 years) were included. Fifty-three percent were female. The median [IQR] caliber of the intramuscular gluteal vessels was 1.47 [1.15-1.88] mm, significantly greater than that of the subcutaneous vessels 1.09 [0.72-1.44] mm (p < 0.001). Vascular density was higher intramuscularly, as 4.5% of the area of the muscle was occupied by blood vessels, as opposed to 0.3% in the adipose tissue. CONCLUSION: The analysis of the CBCT scans showed a higher vascular density and larger vessels intramuscularly. We, therefore, recommend the injection of autologous fat merely to the subcutaneous plane. LEVEL OF EVIDENCE II: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Viabahn stent graft for arterial injury management: safety, technical success, and long-term outcome.

BACKGROUND: The Viabahn stent graft has emerged as an integral tool for managing vascular diseases, but there is limited long-term data on its performance in emergency endovascular treatment. This study aimed to assess safety, technical success, and long-term efficacy of the Viabahn stent graft in emergency treatment of arterial injury. METHODS: We conducted a retrospective single tertiary centre analysis of patients who underwent Viabahn emergency arterial injury treatment between 2015 and 2020. Indication, intraoperative complications, technical and clinical success, and major adverse events at 30 days were evaluated. Secondary efficacy endpoints were the primary and secondary patency rates assessed by Kaplan-Meier analysis. RESULTS: Forty patients (71 ± 13 years, 19 women) were analyzed. Indications for Viabahn emergency treatment were extravasation (65.0%), arterio-venous fistula (22.5%), pseudoaneurysm (10.0%), and arterio-ureteral fistula (2.5%). No intraoperative adverse events occurred, technical and clinical success rates were 100%. One acute stent graft occlusion occurred in the popliteal artery on day 9, resulting in a 30-day device-related major-adverse-event rate of 2.5%. Median follow-up was 402 days [IQR, 43-1093]. Primary patency rate was 97% (95% CI: 94-100) in year 1, and 92% (95% CI: 86-98) from years 2 to 6. One stent graft occlusion occurred in the external iliac artery at 18 months; successful revascularization resulted in secondary patency rates of 97% (95% CI: 94-100) from years 1 to 6. CONCLUSION: Using Viabahn stent graft in emergency arterial injury treatment had 100% technical and clinical success rates, a low 30-day major-adverse-event rate of 2.5%, and excellent long-term patency rates.

Quantitative Flow Measurements of Pelvic Venous Vasculature Using 4D Flow MRI.

RATIONALE AND OBJECTIVES: To evaluate 4D Flow magnetic resonance imaging (MRI) sequences for quantitative flow measurements of the pelvic venous vasculature. MATERIALS AND METHODS: A prospective study of healthy volunteers was performed. After informed consent all subjects underwent 4D flow sequences at a 3 T MRI scanner with different isotropic resolution and different velocity encoding (Venc) settings: (sequence #1) voxel size (VS) 1.63 mm3, Venc 50 cm/s; (sequence #2) VS 1.63 mm3, Venc 100 cm/s and (sequence #3) VS 2.03 mm3, Venc 50 cm/s. Perfusion parameters were calculated for all venous vessel segments starting at the level of the inferior vena cava and extending caudally to the level of the common femoral vein. For reference, arterial flow was calculated using 1.63 mm3 isotropic resolution with a Venc of 100 cm/s. RESULTS: Ten healthy subjects (median age 28 years, interquartile range [IQR]: 26.25-28 years) were enrolled in this study. Median scanning time was 12:12 minutes (IQR 10:22-13:32 minutes) for sequence #1, 11:02 minutes (IQR 9:57-11:19 minutes) for sequence #2 and 6:10 minutes (IQR 5:44-6:47 minutes) for sequence #3. Flow measurements were derived from all sequences. The venous pelvic vasculature showed similar perfusion parameters compared to its arterial counterpart, for example the right common iliac arterial segment showed a perfusion of 8.32 ml/s (IQR: 6.94-10.68 ml/s) versus 7.29 ml/s (IQR: 4.70-8.90 ml/s) in the corresponding venous segment (P = 0.218). The venous flow measurements obtained from the three investigated sequences did not reveal significant differences. CONCLUSION: 4D Flow MRI is suitable for quantitative flow measurement of the venous pelvic vasculature. To reduce the scanning time without compromising quantitative results, the resolution can be decreased while increasing the Venc. This technique may be utilized in the future for the diagnosis and treatment response assessment of iliac vein compression syndromes.

Optimization of Y-90 Radioembolization Imaging for Post-Treatment Dosimetry on a Long Axial Field-of-View PET/CT Scanner.

BACKGROUND: PET imaging after yttrium-90 (Y-90) radioembolization is challenging because of the low positron fraction of Y-90 (32 × 10-6). The resulting low number of events can be compensated by the high sensitivity of long axial field-of-view (LAFOV) PET/CT scanners. Nevertheless, the reduced event statistics require optimization of the imaging protocol to achieve high image quality (IQ) and quantification accuracy sufficient for post-treatment dosimetry. METHODS: Two phantoms (NEMA IEC and AbdoMan phantoms, mimicking human liver) filled with Y-90 and a 4:1 sphere (tumor)-to-background ratio were scanned for 24 h with the Biograph Vision Quadra (Siemens Healthineers). Eight patients were scanned after Y-90 radioembolization (1.3-4.7 GBq) using the optimized protocol (obtained by phantom studies). The IQ, contrast recovery coefficients (CRCs) and noise were evaluated for their limited and full acceptance angles, different rebinned scan durations, numbers of iterations and post-reconstruction filters. The s-value-based absorbed doses were calculated to assess their suitability for dosimetry. RESULTS: The phantom studies demonstrate that two iterations, five subsets and a 4 mm Gaussian filter provide a reasonable compromise between a high CRC and low noise. For a 20 min scan duration, an adequate CRC of 56% (vs. 24 h: 62%, 20 mm sphere) was obtained, and the noise was reduced by a factor of 1.4, from 40% to 29%, using the full acceptance angle. The patient scan results were consistent with those from the phantom studies, and the impacts on the absorbed doses were negligible for all of the studied parameter sets, as the maximum percentage difference was -3.89%. CONCLUSIONS: With 2i5s, a 4 mm filter and a scan duration of 20 min, IQ and quantification accuracy that are suitable for post-treatment dosimetry of Y-90 radioembolization can be achieved.

Selective Internal Radiotherapy (SIRT) and Chemosaturation Percutaneous Hepatic Perfusion (CS-PHP) for Metastasized Uveal Melanoma: A Retrospective Comparative Study.

Even with liver-targeted therapies, uveal melanoma with hepatic metastasis remains a challenge. The aim of this study was to compare the outcome of patients treated with either SIRT or CS-PHP. We included 62 patients with hepatic metastasized uveal melanoma (n = 34 with SIRT, receiving 41 cycles; n = 28 with CS-PHP, receiving 56 cycles) that received their treatments between 12/2013 and 02/2020 at a single center. We evaluated their response according to the RECIST 1.1, as well as progression-free survival (PFS) and overall survival (OS), after the initiation of the first cycle of the liver-directed treatment using Cox regression, adjusted via propensity score analysis for confounders, including the amount of hepatic involvement. The disease control rate was 18% for SIRT and 30% for CS-PHP. The median (range) of PFS was 127.5 (19-1912) days for SIRT and 408.5 (3-1809) days for CS-PHP; adjusted Cox regression showed no significant difference (p = 0.090). The median (range) of OS was 300.5 (19-1912) days for SIRT and 516 (5-1836) days for CS-PHP; adjusted Cox regression showed a significant difference (p = 0.006). In our patient cohort, patients treated with CS-PHP showed a significantly longer OS than patients treated with SIRT. CS-PHP might therefore be preferable for patients with liver-dominant metastatic uveal melanoma.

Noninvasive and invasive imaging of lower-extremity acute and chronic venous thrombotic disease.

The spectrum of venous thromboembolic (VTE) disease encompasses both acute deep venous thrombosis (DVT) and chronic postthrombotic changes (CPC). A large percentage of acute DVT patients experience recurrent VTE despite adequate anticoagulation, and may progress to CPC. Further, the role of iliocaval venous obstruction (ICVO) in lower-extremity VTE has been increasingly recognized in recent years. Imaging continues to play an important role in both acute and chronic venous disease. Venous duplex ultrasound remains the gold standard for diagnosing acute VTE. However, imaging of CPC is more complex and may involve computed tomography, magnetic resonance, contrast-enhanced ultrasound, or intravascular ultrasound. In this narrative review, we aim to discuss the full spectrum of venous disease imaging for both acute and chronic venous thrombotic disease.

Endovascular treatment of symptomatic hepatic venous outflow obstruction post major liver resection.

PURPOSE: To evaluate efficacy, safety, and outcomes of endovascular treatment of hepatic vein stenosis post major liver resection. METHODS: A retrospective data analysis was performed including all interventional treatments of hepatic vein stenosis post major liver resection since 2010. Post procedural course and clinical parameters including amount of ascites accumulation and relevant laboratory values were assessed during the follow-up period. Primary and primary assisted hepatic venous patency time were calculated. RESULTS: Twelve patients (median age 55.5, IQR 49.75 to 61.5 years) undergoing a total of 16 interventions were included. Interventions were primary stent placement (n = 3), primary balloon angioplasty (n = 8), three re-interventions and two aborted interventions (no significant pressure gradient). Technical success was 100% (16/16). Permanent reduction and / or complete resolution of ascites was achieved in 72% (8/11). Laboratory parameters related to liver function did not show significant improvement after intervention. Median follow-up period was 6 months (IQR: 1.5 to 18 months). The median primary patency time for patients with balloon angioplasty was 11 months (IQR: 1.375 to 22.25 months) and assisted patency time was 13.25 months (IQR: 4.5 to 22.25 months). The median primary patency time for patients with angioplasty and stent placement was 1 months (IQR: 1.0 to 1.5 months) and assisted patency time was 2.0 months (IQR: 1.5 to 2.5months). CONCLUSION: An endovascular approach for the treatment of hepatic venous stenosis post major liver resection is safe and efficient to reduce and / or resolve refractory ascites. However, liver function parameters seem not to be improved by the procedure. Stent placement can be a reasonable option in patients with significant residual stenotic disease post angioplasty.

Balloon angioplasty versus stent placement for the treatment of portal vein stenosis in children: a single center experience.

PURPOSE: To evaluate the safety and efficacy of percutaneous interventional treatment of portal vein stenosis in children. MATERIAL AND METHODS: A retrospective analysis of all interventional treatments for portal vein stenosis in pediatric patients at a single institution from 2010 to 2021 was conducted. Platelet count, spleen size and portal vein flow velocity were assessed during the follow-up period. Primary and primary assisted patency time were determined. RESULTS: A total of ten children (median age 28.5 months, interquartile range (IQR): 2.75-52.5 months) with portal vein stenosis after Mesorex-Shunt (n = 4), liver transplantation (n = 3) and other etiologies (n = 3) underwent 15 interventional procedures. There were five reinterventions and one discontinued intervention. The technical success rate was 93.3% (14/15) and clinical success of treated patients was 100% (14/14). Median follow-up was 18 months (IQR: 13.5-81 months). The median primary patency time for stent placement was 70 months (IQR: 13.5-127.25 months). For balloon angioplasty, the median primary patency time was 9 months (IQR 7.25-11.5 months), while the median assisted primary patency time was 14 months (IQR: 12 to 15 months). Platelet count, spleen size and portal vein flow velocity reliably corresponded to recurrence of portal vein stenosis in asymptomatic patients during follow-up. CONCLUSION: Interventional treatment is a safe and efficient method to treat portal vein stenosis with long patency times, regardless of etiology. Primary stent placement shows a higher primary patency time than balloon angioplasty. Implementation of stent placement as the primary interventional method may improve patency times and reduce the need for repeat reinterventions in pediatric patients.

Improving Bioactive Characteristics of Small Diameter Polytetrafluoroethylene Stent Grafts by Electrospinning: A Comparative Hemocompatibility Study.

Polytetrafluoroethylene (PTFE) is a commonly used biomaterial for the manufacturing of vascular grafts and several strategies, such as coatings, have been explored to improve the hemocompatibility of small-diameter prostheses. In this study, the hemocompatibility properties of novel stent grafts covered with electrospun PTFE (LimFlow Gen-1 and LimFlow Gen-2) were compared with uncoated and heparin-coated PTFE grafts (Gore Viabahn®) using fresh human blood in a Chandler closed-loop system. After 60 min of incubation, the blood samples were examined hematologically and activation of coagulation, platelets, and the complement system were analyzed. In addition, the adsorbed fibrinogen on the stent grafts was measured and the thrombogenicity was assessed by SEM. Significantly lower adsorption of fibrinogen was measured on the surface of heparin-coated Viabahn than on the surface of the uncoated Viabahn. Furthermore, LimFlow Gen-1 stent grafts showed lower fibrinogen adsorption than the uncoated Viabahn®, and the LimFlow Gen-2 stent grafts showed comparable fibrinogen adsorption as the heparin-coated Viabahn®. SEM analysis revealed no sign of thrombus formation on any of the stent surfaces. LimFlow Gen-2 stent grafts covered with electrospun PTFE exhibited bioactive characteristics and revealed improved hemocompatibility in terms of reduced adhesion of fibrinogen, activation of platelets, and coagulation (assessed by ß-TG and TAT levels) similar to heparin-coated ePTFE prostheses. Thus, this study demonstrated improved hemocompatibility of electrospun PTFE. The next step is to conduct in vivo studies to confirm whether electrospinning-induced changes to the PTFE surface can reduce the risk of thrombus formation and provide clinical benefits.

Quantification of Facial Fat Compartment Variations: A Three-Dimensional Morphometric Analysis of the Cheek.

BACKGROUND: Cheek contour is a main determinant of facial attractiveness. The aim of this study was to evaluate the relationship between age, sex, and body mass index (BMI) and cheek fat volume in a large cohort to better understand and treat facial aging. METHODS: The authors performed a retrospective review of the archives of the Department of Diagnostic and Interventional Radiology, University Hospital of Tübingen. Epidemiologic data and medical history were assessed. Cheek superficial and deep fat compartment volumes were measured on magnetic resonance images. Statistical analyses were performed using SPSS and SAS statistical software. RESULTS: A total of 87 patients with a mean age of 46 years (range, 18 to 81 years) were included. The superficial and deep fat compartment volumes of the cheek increased with BMI ( P < 0.001 and P = 0.005), but there was no significant relationship between age and volume. The ratio of superficial versus deep fat did not change with age. No significant difference of the superficial or deep fat compartments was found between men and women in a regression analysis ( P = 0.931 and P = 0.057). CONCLUSIONS: Cheek fat volume measurements on magnetic resonance imaging scans using reconstruction software suggest that the fat volume of the cheek increases with BMI but does not change significantly with age. Further studies are needed to elucidate the role of age-related changes of bone structures or sagging of the fat compartments.

Atherosclerotic plaque composition and specific endovascular considerations in the end stage renal disease patients: a narrative review.

Background and Objective: Vascular calcification (VC) and resulting vascular disease is one of the major causes of cardiovascular morbidity and mortality in patients with chronic kidney disease (CKD). CKD itself is increasingly recognized as a risk factor for cardiac and peripheral arterial disease (PAD). This paper examines the atherosclerotic plaque composition and specific endovascular considerations in the end stage renal disease (ESRD) patients. The literature was reviewed regarding the current status of medical and interventional management arteriosclerotic disease in patients with CKD. Lastly, three representative cases displaying typical endovascular treatment options are provided. Methods: A literature search was performed in PubMed covering publications up to September 2021 as well as discussion with experts in the field. Key Content and Findings: The high prevalence of atherosclerotic lesions in patients with chronic renal failure and high (re-)stenosis cause problems in the medium and long term as vascular calcium load represents one of the most widely encountered predictors of failure of endovascular treatment of PAD and future cardiovascular events (e.g., coronary calcium score). Patients with CKD also suffer from a greater risk for major vascular adverse events in general and worse revascularization outcomes following peripheral vascular intervention. A correlation between calcium burden and drug-coated balloon (DCB) performance has been established for PAD necessitating the need for different tools to cope with vascular calcium such as endoprosthesis or braided stents. Patients with CKD are at a higher risk of developing contrast-induced nephropathy (CIN). In addition to recommendations such as the administration of intravenous fluids, carbon dioxide (CO2) angiography is one option to potentially provide an effective and safe alternative both to iodine-based contrast media allergy and to the use of iodine-based contrast media in patients with CKD. Conclusions: Management and endovascular procedures of patients with ESRD are complex. In the course of time, new endovascular therapy methods have been developed such as directional atherectomy (DA) and the so-called "pave-and-crack" technique to deal with high vascular calcium burden. Besides interventional therapy, vascular patients with CKD benefit from aggressive medical management.

Best crossing of peripheral chronic total occlusions.

Together with colleagues from different disciplines, including cardiologists, interventional radiologists and vascular surgeons, committee members of the of the German Society of Angiology (Deutsche Gesellschaft für Angiologie [DGA]), developed a novel algorithm for the endovascular treatment of peripheral chronic total occlusive lesions (CTOs). Our aim is to improve patient and limb related outcomes, by increasing the success rate of endovascular procedures. This can be achieved by adherence to the proposed crossing algorithm, aiding the standardization of endovascular procedures. The following steps are proposed: (i) APPLY Duplex sonography and if required 3D techniques such as computed tomography or magnetic resonance angiography. This will help you to select the optimal access site. (ii) EVALUATE the CTO cap morphology and distal vessel refilling sites during diagnostic angiography, which are potential targets for a retrograde access. (iii) START with antegrade wiring strategies including guidewire (GW) and support catheter technology. Use GW escalation strategies to penetrate the proximal cap of the CTO, which may usually be fibrotic and calcified. (iv) STOP the antegrade attempt depending on patient specific parameters and the presence of retrograde options, as evaluated by pre-procedural imaging and during angiography. (v) In case of FAILURE, consider advanced bidirectional techniques and reentry devices. (vi) In case of SUCCESS, externalize the GW and treat the CTO. Manage the retrograde access at the end of the endovascular procedure. (vii) STOP the procedure if no progress can be obtained within 3 hours, in case of specific complications or when reaching maximum contrast administration based on individual patient's renal function. Consider radiation exposure both for patients and operators. In this manuscript we systematically follow and explain each of the steps (i)-(vi) based on practical examples from our daily routine. We strongly believe that the integration of this algorithm in the daily practice of endovascular specialists, can improve vessel and patient specific outcomes.

Crossing Algorithm for Infrainguinal Chronic Total Occlusions: An Interdisciplinary Expert Opinion Statement.

A crossing algorithm was developed for the endovascular treatment of peripheral chronic total occlusive lesions (CTOs) to educate, guide, and appropriately influence clinical practice aiming at harmonization and standardization of endovascular procedures. The following steps are proposed: One, duplex sonography and if required computed tomography or magnetic resonance angiography for the selection of the optimal access site. Two, angiographic evaluation of the proximal/distal cap morphology, presence of collaterals at the origin of the proximal cap and at the distal vessel refilling site. In addition, evaluation of distal vessels, including their diameters and quality, and the presence of calcification or stents within the occlusion zone. Three, antegrade wiring strategies, guidewire (GW) and support catheter technology, as well as GW escalation strategies. Stop the antegrade attempt depending on clinical indication for peripheral artery disease treatment and the presence of retrograde options. Four, retrograde access site, support catheter, or sheath insertion and wiring technology from distally. Five, considering strategy change when progress cannot by achieved, using advanced bidirectional techniques and re-entry devices. Six, in case of successful GW passage from retrograde, GW externalization and treatment from antegrade. Management of the retrograde access by internal or external hemostasis at the end of the procedure. Alternatively, stop the procedure if no progress can be obtained within 3 hours or in case of specific complications. By establishing the algorithm in the daily routine of endovascular specialists, improvements in vessel- and patient-specific outcomes are anticipated. In addition, future research, and continuous collaboration between experts is warranted.

Non-contrast MR angiography of pelvic arterial vasculature using the Quiescent interval slice selective (QISS) sequence.

To evaluate Quiescent Interval Slice Selective (QISS) balanced steady-state free precession (bSSFP) and QISS fast low-angle shot (FLASH) sequences for non-contrast Magnetic Resonance Angiography (MRA) of iliac arteries regarding image quality and diagnostic confidence in order to establish these sequences in daily clinical practice. A prospective study of healthy subjects (n = 10) was performed. All subjects underwent the QISS MRI protocol with bSSFP und FLASH sequences. Vessel contrast-to-background ratio (VCBR) were measured in pre-defined vessel segments. Image quality and diagnostic confidence was assessed using a Likert scale (five-point scale). Inter-reader agreement was determined using Cohen's kappa coefficient (κ). Ten healthy subjects (median age 29 years, IQR: 26.25 to 30 years) were included in this prospective study. Median MR examination time was 2:05 min (IQR 1:58 to 2:16) for QISS bSSFP and 4:11 min (IQR 3:57 to 4:32) for QISS FLASH. Both sequences revealed good VCBR in all examined vessel segments. VCBR (muscle tissue) were marginally higher for FLASH sequences (e.g., 0.82 vs. 0.78 in the right femoral artery, p = 0.035*), while bSSFP sequence showed significantly higher VCBR (fat tissue) in the majority of examined arterials vessels (e.g., 0.78 vs. 0.62 in right femoral artery, p = 0.001*). The image quality and diagnostic confidence of both sequences were rated as good to excellent. Moderate to good inter-reader agreement was found. QISS MRA using bSSFP and FLASH sequences are diagnostic for visualization of iliac arterial vasculature. The QISS bSSFP sequence might offer advantages due to the markedly shorter exam time and superior visualization of smaller vessels. The QISS FLASH sequence seems to be a robust alternative for non-contrast MRA since it is less sensitive to magnetic field inhomogeneities.

Functional MRI to quantify perfusion changes of a renal allograft after embolization of an arteriovenous fistula.

Acute allograft injury was observed in a 37-year-old woman within a few weeks after kidney transplantation. Neither renal ultrasound nor computerized tomography (CT) and magnetic resonance (MR) angiography revealed any anomaly. An MR protocol was then performed including arterial spin labeling and intravoxel incoherent motion diffusion weighted imaging. Both arterial spin labeling and the perfusion fraction in the diffusion weighted imaging showed decreased perfusion compared to reference values. The patient subsequently underwent angiography, where an arteriovenous fistula in the upper calix of the transplant kidney was detected and immediate embolization was performed. A second functional MR, performed one week later, demonstrated a 40% increase in organ perfusion. We conclude that functional MR with arterial spin labeling and intravoxel incoherent motion have the potential to provide complementary information of clinical value to conventional imaging for monitoring renal allografts.

Safety and Efficacy of Rotational Thrombectomy for Treatment of Arterial Occlusions of the Lower Extremities: A Large Single-Center Retrospective Study.

PURPOSE: To evaluate the safety and efficacy of rotational thrombectomy (RT) in a large single-center real-world cohort for total vascular occlusions of the lower extremity. MATERIALS AND METHODS: The clinical records and images of all patients between 2010 and 2020 treated via RT (Rotarex, BD) were assessed. Patient demographics, clinical data, procedural characteristics, and outcome parameters were documented. In total, 397 procedures in 293 patients were included (mean age 69.8 ±â€Š12.0 years; 64.8 % male). Occlusions were acute (47.5 %), subacute and acute-on-chronic (22.2 %), and chronic (30.3 %). The target lesions were the iliac artery (7.1 %), iliac/femoropopliteal (5.0 %), femoropopliteal (59.4 %), femoropopliteal/below-the-knee (27.0 %), below-the-knee (1.5 %), and after bypass surgery (14.9 %). Lesion length was > 20 cm in 61.5 % of cases. RESULTS: Clinically successful revascularization was achieved in 90.4 % of cases. Additional thrombolysis was necessary for 32.0 % of procedures. The arithmetic mean ankle-brachial index increased from 0.33 ±â€Š0.29 to 0.81 ±â€Š0.25 (p < 0.0001). Bypass grafts were less likely to be fully treatable and required additional lysis (p < 0.001). The overall primary patency (no clinically driven target lesion revascularization) was 93.2 %, 88.8 %, 79.1 %, and 72.4 % at 1, 3, 6, and 12 months, respectively. Adverse events occurred in 46.1 % of cases, of which peripheral embolization (22.4 %) was most frequent, requiring interventional treatment in 67.4 % of cases. RT was directly associated with 7.1 % (n = 28) of complications, which consisted of perforations 2.8 %, arteriovenous fistula 1.3 %, and dissections 2.0 %. CONCLUSION: Rotational thrombectomy is a safe and efficient method for the treatment of occlusions of the arterial circulation of the lower extremity with bypass occlusions having a higher propensity for residual thrombi requiring further lysis therapy. KEY POINTS: · Rotational thrombectomy was safe and efficacious for treating occlusions of the lower extremities.. · Rotational thrombectomy was associated with 7.1 % of complications.. · Distal embolization occurred in 22.4 % of cases with 67.4 % requiring interventional treatment.. · Primary patency was 93.2 %, 88.8 %, 79.1 %, 72.4 % after 1, 3, 6, and 12 months, respectively.. CITATION FORMAT: · Artzner C, Martin I, Hefferman G et al. Safety and Efficacy of Rotational Thrombectomy for Treatment of Arterial Occlusions of the Lower Extremities: A Large Single-Center Retrospective Study. Fortschr Röntgenstr 2023; 195: 406 - 415.