3 Tesla magnetic resonance imaging in patients with cardiac implantable electronic devices: a single centre experience.

AIMS: Three Tesla (T) magnetic resonance imaging (MRI) provides critical imaging information for many conditions. Owing to potential interactions of the magnetic field, it is largely withheld from patients with cardiac implantable electronic devices (CIEDs). Therefore, we assessed the safety of 3T MRI in patients with '3T MRI-conditional' and 'non-3T MRI-conditional' CIEDs. METHODS AND RESULTS: We performed a retrospective single-centre analysis of clinically indicated 3T MRI examinations in patients with conventional pacemakers, cardiac resynchronization devices, and implanted defibrillators from April 2020 to May 2022. All CIEDs were interrogated and programmed before and after scanning. Adverse events included all-cause death, arrhythmias, loss of capture, inappropriate anti-tachycardia therapies, electrical reset, and lead or generator failure during or shortly after MRI. Changes in signal amplitude and lead impedance were systematically assessed. Statistics included median and interquartile range. A total of 132 MRI examinations were performed on a 3T scanner in 97 patients. Thirty-five examinations were performed in patients with 'non-3T MRI-conditional' CIEDs. Twenty-six scans were performed in pacemaker-dependent patients. No adverse events occurred during or shortly after MRI. P-wave or R-wave reductions ≥ 50 and ≥ 25%, respectively, were noted after three (2.3%) scans, all in patients with '3T MRI-conditional' CIEDs. Pacing and shock impedance changed by ± 30% in one case (0.7%). Battery voltage and stimulation thresholds did not relevantly change after MRI. CONCLUSION: Pending verification in independent series, our data suggest that clinically indicated MRI scans at 3T field strength should not be withheld from patients with cardiac pacemakers or defibrillators.

First experience with Walrus balloon guide catheter in a whole-body flow model.

PURPOSE: Flow arrest using a balloon guide catheter (BGC) in mechanical thrombectomy (MT) due to large vessel occlusion has been associated with better outcomes. Known limitations of currently commercially available BGCs are incompatibility with large bore aspiration catheters (AC) and lack of distal flexibility. Walrus presents variable stiffness and compatibility with large bore AC. The goal of this study is to describe the first experience with Walrus in a realistic stroke simulation model. METHODS: A full-length modular vascular model under physiological conditions was used. 8F+-Walrus inner-diameter (ID) 0.087in 95 cm combined with 6F-Sofia AC ID 0.070in 131 cm and an 8F-Flowgate2 BGC ID 0.084in 95 cm with a 5F-Sofia AC ID 0.055in 125 cm were used to perform aspiration MT. User surveys, access to target and occlusion site, technique, time of delivery, anatomical change, and catheter kick-back were assessed. RESULTS: Seven neuroradiologists with average of 10 years-experience in MT performed primary aspiration using the above-mentioned combinations in three different anatomies (N = 41). All operators would likely (29%) or very likely (71%) use again Walrus in combination with large bore AC and the majority (86%) found its navigability easier than with other BGCs. Time to reach final BGC position and catheter kick-back did not differ significantly among anatomies or catheter combinations (p > 0.05). However, Walrus was more likely to reach ICA petrous segment (p < 0.05) and intracranial occlusion with AC (p < 0.01). CONCLUSION: The Walrus combined with large bore AC presented significantly better distal access and navigability for primary aspiration in an in vitro stroke model.

How Much of the Thrombectomy Related Improvement in Functional Outcome Is Already Apparent at 24 Hours and at Hospital Discharge?

BACKGROUND: Early neurological status has been described as predictor of functional outcome in patients with anterior circulation stroke after mechanical thrombectomy. It remains unclear to what proportion the improvement of functional outcome at day 90 is already apparent at 24 hours and at hospital discharge and how later factors impact outcome. METHODS: All patients enrolled in the German Stroke Registry (June 2015-December 2019) with anterior circulation stroke and availability of baseline data and neurological status were included. A mediation analysis was conducted to investigate the effect of successful recanalization (Thrombolysis in Cerebral Infarction scale score ≥2b) on good functional outcome (modified Rankin Scale score ≤2 at day 90) with mediation through neurological status (National Institutes of Health Stroke Scale [NIHSS] at 24 hours and at hospital discharge). RESULTS: Three thousand fifty-seven patients fulfilled the inclusion criteria, thereof 2589 (85%) with successful recanalization and 1180 (39%) with good functional outcome. In a multivariate logistic regression analysis, probability of good outcome was significantly associated with age (odds ratio [95% CI], 0.95 [0.94-0.96]), prestroke modified Rankin Scale (0.48 [0.42-0.55]), admission-NIHSS (0.96 [0.94-0.98]), 24-hour NIHSS (0.83 [0.81-0.84]), diabetes (0.56 [0.43-0.72]), proximal middle cerebral artery occlusions (0.78 [0.62-0.97]), passes (0.88 [0.82-0.95]), Alberta Stroke Program Early CT Score (1.07 [1.00-1.14]), successful recanalization (2.39 [1.68-3.43]), intracerebral hemorrhage (0.51 [0.35-0.73]), and recurrent strokes (0.54 [0.32-0.92]). Mediation analysis showed a 20 percentage points (95% CI' 17-24 percentage points) increase of probability of good functional outcome after successful recanalization. Fifty-four percent (95% CI' 44%-66%) of the improvement in functional outcome was explained by 24-hour NIHSS and 75% (95% CI' 62%-90%) by NIHSS at hospital discharge. CONCLUSIONS: Fifty-four percent of the improvement in functional outcome after successful recanalization is apparent in NIHSS at 24 hours, 75% in NIHSS at hospital discharge. Other unknown factors not apparent in NIHSS at the 2 time points investigated account for the remaining effect on long term outcome, suggesting, among others, clinical relevance of delayed neurological improvement and deterioration. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT03356392.

Long-term survival of an adolescent glioblastoma patient under treatment with vinblastine and valproic acid illustrates importance of methylation profiling.

Glioblastoma (GBM) is an exceptionally aggressive brain tumor with a dismal prognosis, demanding fast and precise classification as a base for patient-specific treatment strategies. Here, we report on an adolescent patient with a histologically bona fide GBM that shows a molecular methylation profile suggesting a low-grade glioma-like subgroup. Despite an early relapse, intolerance of temozolomide, and change of treatment strategy to vinblastine and valproic acid (VPA), the patient is now in good clinical condition after more than 5 years since initial diagnosis. This case stresses the merit of methylation array data for clinical prognosis and treatment planning.

ADAM8 affects glioblastoma progression by regulating osteopontin-mediated angiogenesis.

Glioblastoma multiforme (GBM) is the most aggressive type of brain cancer with a median survival of only 15 months. To complement standard treatments including surgery, radiation and chemotherapy, it is essential to understand the contribution of the GBM tumor microenvironment. Brain macrophages and microglia particularly contribute to tumor angiogenesis, a major hallmark of GBM. ADAM8, a metalloprotease-disintegrin strongly expressed in tumor cells and associated immune cells of GBMs, is related to angiogenesis and correlates with poor clinical prognosis. However, the specific contribution of ADAM8 to GBM tumorigenesis remains elusive. Knockdown of ADAM8 in U87 glioma cells led to significantly decreased angiogenesis and tumor volumes of these cells after stereotactic injection into striate body of mice. We found that the angiogenic potential of ADAM8 in GBM cells and in primary macrophages is mediated by the regulation of osteopontin (OPN), an important inducer of tumor angiogenesis. By in vitro cell signaling analyses, we demonstrate that ADAM8 regulates OPN via JAK/STAT3 pathway in U87 cells and in primary macrophages. As ADAM8 is a dispensable protease for physiological homeostasis, we conclude that ADAM8 could be a tractable target to modulate angiogenesis in GBM with minor side-effects.

Increased urinary bladder volume improves the detectability of urinary stones at the ureterovesical junction in non-enhanced computed tomography (NECT).

OBJECTIVES: To evaluate the influence of the urinary bladder volume on the detectability of urolithiasis at the ureterovesical junction (UVJ) using a low-dose CT (LD-CT) with iterative reconstruction (IR) and a standard-dose CT (SD-CT) without IR in a large cohort. METHODS: Four hundred patients (278 males (69.5%), mean 44.6 ± 14.7 years) with urolithiasis at the UVJ were investigated either by an LD-CT with IR (n = 289, 72%) or an SD-CT without IR (n = 111, 28%) protocol. The detectability of distal urolithiasis was assessed by a dichotomous assessment (definite or questionable) by two radiologists in consensus and by a quantitative analysis of the signal density distribution across a line drawn parallel to the distal ureter. Based on the resulting graph, minimum/maximum density values and mean/maximum upslopes and downslopes were derived and calculated automatically. In all patients, the total bladder volume was calculated by a slice-by-slice approach on axial CT images. RESULTS: Patients with definite stones showed significantly higher urinary bladder volumes compared to patients with questionable stones in both LD-CT and SD-CT (p < 0.01). These results were independent of stones' length and patients' BMI values. Using cutoffs of 92 ml for LD-CT and 69 ml for SD-CT, high positive predictive values/accuracy rates of 96%/85% (LD-CT) and 98%/86% (SD-CT) were observed to identify definite urinary stones. CONCLUSIONS: Urinary bladder volume has a significant impact on the detectability of distal urolithiasis. Moderate bladder filling by pre-CT hydration with subsequent CT scan at the time of high urge to void increases the detectability of urinary stones at the UVJ in clinical routine. KEY POINTS: • Urinary bladder volume significantly affects the detectability of distal urolithiasis • Higher bladder volumes are associated with improved detectability of distal urinary stones • Oral pre-CT hydration for urolithiasis is easily applicable and cost-effective.

Diagnostic prediction of complicated appendicitis by combined clinical and radiological appendicitis severity index (APSI).

OBJECTIVES: To develop a routinely applicable severity index for the management of acute appendicitis in adults using combined clinical and radiological parameters and retroperitoneal space planes (RSP). METHODS: Two hundred consecutive patients with histologically proven acute appendicitis and available presurgical CT scans were analysed retrospectively. Two radiologists assessed all CT scans for morphologic sings of appendicitis and six RSP. Clinical parameters were age, body temperature, C-reactive protein (CRP), white blood cell count, and duration of symptoms. Radiological parameters were appendix diameter and wall thickness, periappendiceal fat stranding and fluid, intraluminal and extraluminal air, thinning of appendiceal wall, caecal wall thickening, appendicolith and abscess formation. RESULTS: One hundred and three patients (51%) had histologically proven complicated appendicitis. Based on three clinical (age ≥52 years, body temperature ≥37.5°C, duration of symptoms ≥48 h) and four computed tomography (CT) findings (appendix diameter ≥14 mm, presence of periappendiceal fluid, extraluminal air, perityphlitic abscess), the APSI was developed using regression coefficients of multivariate logistic regression analyses with a maximum of 10 points. A score of ≥4 points predicted complicated appendicitis with a positive predictive value of 92% and a negative predictive value of 83%. Substantial to excellent interobserver agreement was found for the four radiological parameters of the APSI [intraclass correlation coefficient (ICC), 0.78-0.83]. The RSP evaluation presented no added value for the diagnosis of complicated appendicitis. CONCLUSIONS: Using APSI, an accurate and simple prediction of complicated appendicitis in adults was possible. The RSP count was not useful for the diagnosis of complicated appendicitis. KEY POINTS: • Appendicitis severity score provides an accurate and simple prediction of complicated appendicitis • Appendicitis severity score ≥4 accurately predicted complicated appendicitis (PPV 92%;NPV 83%) • Evaluation of retroperitoneal space planes was not useful in diagnosing complicated appendicitis.

Outcomes with General Anesthesia Compared to Conscious Sedation for Endovascular Treatment of Medium Vessel Occlusions: Results of an International Multicentric Study.

BACKGROUND: Optimal anesthetic strategy for the endovascular treatment of stroke is still under debate. Despite scarce data concerning anesthetic management for medium and distal vessel occlusions (MeVOs) some centers empirically support a general anesthesia (GA) strategy in these patients. METHODS: We conducted an international retrospective study of MeVO cases. A propensity score matching algorithm was used to mitigate potential differences across patients undergoing GA and conscious sedation (CS). Comparisons in clinical and safety outcomes were performed between the two study groups GA and CS. The favourable outcome was defined as a modified Rankin Scale (mRS) 0-2 at 90 days. Safety outcomes were 90-days mortality and symptomatic intracranial hemorrhage (sICH). Predictors of a favourable outcome and sICH were evaluated with backward logistic regression. RESULTS: After propensity score matching 668 patients were included in the CS and 264 patients in the GA group. In the matched cohort, either strategy CS or GA resulted in similar rates of good functional outcomes (50.1% vs. 48.4%), and successful recanalization (89.4% vs. 90.2%). The GA group had higher rates of 90-day mortality (22.6% vs. 16.5%, p < 0.041) and sICH (4.2% vs. 0.9%, p = 0.001) compared to the CS group. Backward logistic regression did not identify GA vs CS as a predictor of good functional outcome (OR for GA vs CS = 0.95 (0.67-1.35)), but GA remained a significant predictor of sICH (OR = 5.32, 95% CI 1.92-14.72). CONCLUSION: Anaesthetic strategy in MeVOs does not influence favorable outcomes or final successful recanalization rates, however, GA may be associated with an increased risk of sICH and mortality.

Evaluation of intracranial stenting in a simulated training and assessment environment for neuroendovascular procedures.

Purpose: Given the inherent complexity of neurointerventional procedures and the associated risks of ionizing radiation exposure, it is crucial to prioritize ongoing training and improve safety protocols. The aim of this study is to assess a training and evaluation in-vitro environment using a vascular model of M1 stenosis, within a clinical angiography suite, without relying on animal models or X-ray radiation. Materials and methods: Using a transparent model replicating M1 stenosis, we conducted intracranial stenting procedures with four different setups (Gateway & Wingspan, Gateway & Enterprise, Neurospeed & Acclino, and Pharos Vitesse). A video camera was integrated with the angiography system's monitor for real-time visualization, while a foot switch was employed to simulate live fluoroscopy. Three neuroradiologists with varying levels of expertise performed each procedure for three times. The total duration of fluoroscopy as well as the time from passing the stenosis with the wire to completion of the procedure were recorded using a dedicated software designed for this experimental setup. Results: Compared to the Gateway & Wingspan procedure, the total fluoroscopy time reduced significantly with the Gateway & Enterprise, Neurospeed & Acclino, and Pharos Vitesse procedures by 51.56 s, 111.33 s, and 144.89 s, respectively (p < 0.001). Additionally, physicians with under 2 years and over 5 years of experience reduced FT by 62.83 s and 106.42 s, respectively, (p < 0.001), compared to a novice physician. Similar trends were noted for the time of wire distal to stenosis, with significant reductions for Neurospeed & Acclino and Pharos Vitesse compared to both Gateway & Wingspan as well as Gateway & Enterprise (all p < 0.001). Conclusion: Procedures requiring wire exchange maneuvers exhibited nearly twice the fluoroscopy time in comparison to balloon-mounted stenting or stent-placement via PTA balloon catheters. The more experienced neuroradiologist demonstrated significantly quicker performance in line with expectations in a real-life clinical setting, when compared to the less experienced interventionalist. This in-vitro setup allowed the evaluation of alternative technical approaches and differences in experience of operators without the use of animal models or X-ray. The setup combines advantages of simulators and silicone vessel models in a realistic working environment.

Predictors of functional outcome after thrombectomy for M2 occlusions: a large scale experience from clinical practice.

Mechanical thrombectomy (MT) for acute ischemic stroke with medium vessel occlusions is still a matter of debate. We sought to identify factors associated with clinical outcome after MT for M2-occlusions based on data from the German Stroke Registry-Endovascular Treatment (GSR-ET). All patients prospectively enrolled in the GSR-ET from 05/2015 to 12/2021 were analyzed (NCT03356392). Inclusion criteria were primary M2-occlusions and availability of relevant clinical data. Factors associated with excellent/good outcome (modified Rankin scale mRS 0-1/0-2), poor outcome/death (mRS 5-6) and mRS-increase pre-stroke to day 90 were determined in multivariable logistic regression. 1348 patients were included. 1128(84%) had successful recanalization, 595(44%) achieved good outcome, 402 (30%) had poor outcome. Successful recanalization (odds ratio [OR] 4.27 [95% confidence interval 3.12-5.91], p < 0.001), higher Alberta stroke program early CT score (OR 1.25 [1.18-1.32], p < 0.001) and i.v. thrombolysis (OR 1.28 [1.07-1.54], p < 0.01) increased probability of good outcome, while age (OR 0.95 [0.94-0.95], p < 0.001), higher pre-stroke-mRS (OR 0.36 [0.31-0.40], p < 0.001), higher baseline NIHSS (OR 0.89 [0.88-0.91], p < 0.001), diabetes (OR 0.52 [0.42-0.64], p < 0.001), higher number of passes (OR 0.75 [0.70-0.80], p < 0.001) and intracranial hemorrhage (OR 0.26 [0.14-0.46], p < 0.001) decreased the probability of good outcome. Additional predictors of mRS-increase pre-stroke to 90d were dissections, perforations (OR 1.59 [1.11-2.29], p < 0.05) and clot migration, embolization (OR 1.67 [1.21-2.30], p < 0.01). Corresponding to large-vessel-occlusions, younger age, low pre-stroke-mRS, low severity of acute clinical disability, i.v. thrombolysis and successful recanalization were associated with good outcome while diabetes and higher number of passes decreased probability of good outcome after MT in M2 occlusions. Treatment related complications increased probability of mRS increase pre-stroke to 90d.

Remote Training of Neurointerventions by Audiovisual Streaming : Experiences from the European ESMINT-EYMINT E-Fellowship Program.

BACKGROUND: Remote access of trainees to training centers via video streaming (tele-observership, e­fellowship) emerges as an alternative to acquire knowledge in endovascular interventions. Situational awareness is a summary term that is also used in surgical procedures for perceiving and understanding the situation and projecting what will happen next. A high situational awareness would serve as prerequisite for meaningful learning success during tele-observerships. We hypothesized that live perception of the angiographical procedures using streaming technology is feasible and sufficient to gain useful situational awareness of the procedure. METHODS: During a European tele-observership organized by the European Society of Minimally Invasive Neurological Therapy (ESMINT) and its trainee association (EYMINT), a total of six neurointerventional fellows in five countries observed live cases performed by experienced neurointerventionalists (mentors) in six different high-volume neurovascular centers across Europe equipped with live-streaming technology (Tegus Medical, Hamburg, Germany). Cases were prospectively evaluated during a 12-month period, followed by a final questionnaire after completion of the course. RESULTS: A total of 102/161 (63%) cases with a 1:1 allocation of fellow and mentor were evaluated during a 12-month period. Most frequent conditions were ischemic stroke (27.5%), followed by embolization of unruptured aneurysms (25.5%) and arteriovenous malformations (AVMs) (15.7%). A high level of situational awareness was reported by fellows in 75.5% of all cases. After finishing the program, the general improvement of neurointerventional knowledge was evaluated to be extensive (1/6 fellows), substantial (3/6), and moderate (2/6). The specific fields of improvement were procedural knowledge (6/6 fellows), technical knowledge (3/6) and complication management (2/6). CONCLUSION: Online streaming technology facilitates location-independent training of complex neurointerventional procedures through high levels of situational awareness and can therefore supplement live hands-on-training. In addition, it leads to a training effect for fellows with a perceived improvement of their neurointerventional knowledge.

Bobble-head doll syndrome: therapeutic outcome and long-term follow-up in four children.

Bobble-head doll syndrome (BHDS) is a complex syndrome with the dominant symptom of repetitive anteroposterior head movement. Only 57 patients are quoted in the literature. The etiology of this syndrome remains unknown and no standard treatment has yet been established. We hereby report four cases treated at our department. All the patients presented a psychomotor retardation due to an obstructive hydrocephalus. All the patients were treated using neuroendoscopic techniques: two with ventriculocystostomy, and two with ventriculocystocisternostomy. Cyst decompression was achieved in all four cases and clinical recovery was evident in three of the four patients observed. After surgery, BHDS persisted longer the more the subsequent treatment was delayed. In this article, we provide a concise overview of the theories of pathogenesis, presentation, and management of this syndrome. Based on our own experience, we state that the method of choice should be the neuroendoscopy and this must be performed promptly after diagnosis is made.

Novel synthetic clot analogs for in-vitro stroke modelling.

PURPOSE: The increased demand for training of mechanical thrombectomy in ischemic stroke and development of new recanalization devices urges the creation of new simulation models both for training and device assessment. Clots properties have shown to play a role in procedural planning and thrombectomy device effectiveness. In this study, we analyzed the characteristics and applicability of completely synthetic, animal-free clots in the setting of an in-vitro model of mechanical thrombectomy for training and device assessment. METHODS: Synthetic clots based on agarose (n = 12) and silicone (n = 11) were evaluated in an in-vitro neurointervention simulation of mechanical thrombectomy with clot extraction devices. Calcified clots of mixed nature were simulated with addition of 3D printed structures. 9 clots were excluded due to insufficient vessel occlusion and failure to integrate with clot extraction device. Synthetic thrombi were characterized and compared using a categorical score-system on vessel occlusion, elasticity, fragmentation, adherence and device integration. RESULTS: Both agarose-based and silicone-based clots demonstrated relevant flow arrest and a good integration with the clot extraction device. Silicone-based clots scored higher on adherence to the vessel wall and elasticity. CONCLUSION: Selected synthetic clots can successfully be implemented in an in-vitro training environment of mechanical thrombectomy. The clots' different properties might serve to mimic fibrin-rich and red blood cell-rich human thrombi.

Volume of the amygdala is reduced in patients with narcolepsy - a structural MRI study.

OBJECTIVE: Based on the clinical observation that patients suffering from narcolepsy with cataplexy (NC) have cataplectic attacks when they experience positive emotions, it is therefore hypothesised that the abnormal processing of external emotional input through the limbic system, or motor dysregulation induced by emotions, takes place during these episodes. To date, imaging studies have failed to reveal consistent brain abnormalities in NC patients. METHODS: Considering the discrepancies in reported structural or functional abnormalities of the hypothalamus, amygdala, and nucleus accumbens, we used the MRI volumetry to determine the volumes of the amygdala and nucleus accumbens in a group of eleven patients with NC (5 males and 6 females, mean age 41.7 years ± 17.7). This data was compared to an equal number of examinations in healthy volunteers matched for age and gender. RESULTS: We found a decrease in the amygdalar volume of NC patients in both raw (p<0.001) and relative (p<0.01) data sets. The difference in amygdalar volume between healthy volunteers and NC patients was about 17%. In contrast to the amygdala, we did not find any differences in the volumes of nucleus accumbens. CONCLUSION: In the present MRI volumetric study, we found bilateral gray matter loss in the amygdala only.

Efficiency of Percutaneous Stent Angioplasty in Renal Artery Stenosis - 15 Years of Experience at a Single Center.

PURPOSE: To determine the therapeutic efficiency of percutaneous revascularization in renal artery stenosis (RAS), as well as the role of comprehensive factors such as patient selection and degree of artery stenosis, on clinical outcome. METHODS AND MATERIALS: 101 patients with hemodynamically relevant RAS underwent percutaneous angioplasty (PTA). 65.7 % were male (mean age: 64 years; range: 18-84). The clinical data was retrospectively analyzed. The serum creatinine (Cr), glomerular filtration rate (GFR), and blood pressure (BP) levels pre- and postprocedural, between 6 months and 1 year, were retrospectively collected and statistically analyzed. RESULTS: Follow-up data was available in 34 (33.7 %) and 28 patients (27.7 %) for Cr and MAP, respectively. A significant drop in mean arterial pressure (MAP) was observed on follow-up (mean -5.27 mmHg). Higher baseline Cr and MAP values showed a more pronounced drop in the follow-up (Cr: p 0.002; difference to baseline -0.25 mg/dL, 95 %CI:-0.36, -0.07 and BP p < 0.001; diff. to baseline -0.72 mmHg; 95 %CI: -1.4, -0.40). There was no association between comorbidities, gender, and degree of stenosis with renal and BP outcome. No significant improvement in renal function was observed on follow-up (mean Cr drop: -0.015 mg/dL). The age group 51-60 years showed a significant improvement in BP (p 0.030; diff. to baseline -19.2 mmHg; 95 %CI: -34, -4.3). There was a slight reduction in antihypertensive medication following angioplasty (0.2 fewer). Minor complications were recorded in five procedures (4.9 %). CONCLUSION: Percutaneous renal artery revascularization in the presence of atherosclerotic RAS is a safe procedure associated with a significant drop in post-procedural BP. No significant improvement in renal function was observed. Further prospective studies focused on patient selection are necessary. KEY POINTS: · Percutaneous stent angioplasty in renal artery stenosis is associated with a significant improvement in post-procedural blood pressure control.. · There is no improvement in renal function after percutaneous stent angioplasty for renal artery stenosis (RAS).. · Percutaneous stent angioplasty is a safe procedure.. CITATION FORMAT: · Guerreiro H, Avanesov M, Dinnies S et al. Efficiency of Percutaneous Stent Angioplasty in Renal Artery Stenosis - 15 Years of Experience at a Single Center. Fortschr Röntgenstr 2021; 193: 298 - 304.

Feasibility of a customizable training environment for neurointerventional skills assessment.

OBJECTIVE: To meet increasing demands to train neuroendovascular techniques, we developed a dedicated simulator applying individualized three-dimensional intracranial aneurysm models ('HANNES'; Hamburg Anatomic Neurointerventional Endovascular Simulator). We hypothesized that HANNES provides a realistic and reproducible training environment to practice coil embolization and to exemplify disparities between neurointerventionalists, thus objectively benchmarking operators at different levels of experience. METHODS: Six physicians with different degrees of neurointerventional procedural experience were recruited into a standardized training protocol comprising catheterization of two internal carotid artery (ICA) aneurysms and one basilar tip aneurysm, followed by introduction of one framing coil into each aneurysm and finally complete coil embolization of one determined ICA aneurysm. The level of difficulty increased with every aneurysm. Fluoroscopy was recorded and assessed for procedural characteristics and adverse events. RESULTS: Physicians were divided into inexperienced and experienced operators, depending on their experience with microcatheter handling. Mean overall catheterization times increased with difficulty of the aneurysm model. Inexperienced operators showed longer catheterization times (median; IQR: 47; 30-84s) than experienced operators (21; 13-58s, p = 0.011) and became significantly faster during the course of the attempts (rho = -0.493, p = 0.009) than the experienced physicians (rho = -0.318, p = 0.106). Number of dangerous maneuvers throughout all attempts was significantly higher for inexperienced operators (median; IQR: 1.0; 0.0-1.5) as compared to experienced operators (0.0; 0.0-1.0, p = 0.014). CONCLUSION: HANNES represents a modular neurointerventional training environment for practicing aneurysm coil embolization in vitro. Objective procedural metrics correlate with operator experience, suggesting that the system could be useful for assessing operator proficiency.

Clinico-radiological comparison and short-term prognosis of single acute pancreatitis and recurrent acute pancreatitis including pancreatic volumetry.

PURPOSE: The necrosis-fibrosis hypothesis describes a continuum between single attacks of acute pancreatitis (SAP), recurrent acute pancreatitis (RAP) and chronic pancreatitis (CP) with endocrine and exocrine pancreatic insufficiency. For prevention purposes we evaluated clinico-radiological parameters and pancreatic volumetry to compare SAP and RAP and provide prognostic relevance on short-term mortality, need for intervention and the hospitalization duration. MATERIALS AND METHODS: We retrospectively investigated 225 consecutive patients (150 males, range 19-97years) with acute pancreatitis (74%SAP, 26%RAP) according to the revised Atlanta classification. All patients received an intravenous contrast-enhanced CT after a median time of 5 (IQR 5-7) days after onset of symptoms. Two experienced observers rated the severity of AP by 3 CT scores (CTSI, mCTSI, EPIC). Moreover, total pancreatic volumes and additional parenchymal necrosis volumes were assessed, when appropriate. Clinical parameters were etiology of AP, lipase on admission, CRP 48 hours after admission (CRP48), and the presence of organ dysfunction, assessed by the modified Marshall score. The modified Marshall score included systolic blood pressure, serum creatinine, and the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2 ratio) and was assessed on admission and 48 hours after admission to find patients with persistent organ failure. Outcome parameters were total hospitalization duration, short-term mortality and need for intervention. RESULTS: Lipase, CRP48, etiology of AP, EPIC, PaO2/FiO2 ratio, and the presence of a pleural effusion differed significantly in both groups (p<0.05). In 109 patients with interstitial edematous AP, the total pancreatic volume was significantly smaller in patients with RAP compared to those with SAP (69±35cm3; (RAP) vs 106±45cm3; (SAP), p<0.001). All outcome parameters including the mortality rates (SAP vs. RAP: 15% vs. 7%) were comparable in both groups (p>0.05). In the necrotizing RAP group, only the necrotic volume correlated significantly with total hospitalization time (r = 0.72, p<0.001), whereas the systolic blood pressure was the only, but weak predictor for short-term mortality (ß-coefficient: -0.05, p = 0.03) and the need for intervention (ß-coefficient: -0.02, p = 0.048) in the total RAP group. In patients with SAP, the modified Marshall score was the strongest predictor of short-term mortality, followed by the mCTSI on multivariate logistic regression (Marshall score: ß-coefficient: 1.79, p<0.001; mCTSI: ß-coefficient: 0.40, p<0.001). CTSI was the best predictor for required intervention in necrotizing SAP (ß-coefficient: 0.46, p<0.001), followed by the volume of intrapancreatic necrosis (ß-coefficient: 0.17, p = 0.03). CONCLUSION: Total pancreatic volume differed significantly between interstitial RAP and SAP and intrapancreatic necrosis volume revealed prognostic value for the total hospitalization duration in necrotizing RAP. Although all outcome parameters were comparable between SAP and RAP, only systolic blood pressure and pancreatic volumetry were prognostic in RAP. In SAP, only the modified Marshall score and mCTSI revealed prognostic value for short-term mortality, whereas CTSI was predictive for the need for intervention.