Increased aortic repair in Germany correlates with reduction of death caused by aortic aneurysms but not aortic dissections.

INTRODUCTION: We asked if there is a significant correlation between the increasing trend in aortic repair (AR) and decreasing aortic aneurysm (AA) and aortic dissection (AD) mortality? Therefore, we retrospectively analyzed all aortic repairs in patients with AA and AD and its correlation with disease-specific death rates and hospitalizations for ruptured AA and AD in Germany. METHODS: We retrieved the number of cases hospitalized for AA and AD as well as the procedures in these cases from the Federal Bureau of Statistics (DRG statistics) and death rates from the national mortality statistic published by the Federal Statistical Office in Germany for the years 2006-2017. RESULTS: From 2006 to 2017, the total number of hospitalized cases admitted with principal diagnosis of AA increased by 25.8% and that of AD by 56.7%. That of cases with the principal diagnosis of ruptured AA (rAA) remained unchanged (-2.5%) and that with rAD increased by 54.6%. The number of (open and endovascular) procedures in cases hospitalized for AA increased by 39.4% and for AD by 126.4%. The age-adjusted death rates in Germany for AA decreased from 4.0 to 2.9 per 100,000 inhabitants and that for AD increased from 1.0 to 1.4. The decrease in death attributed to AA cases can be described by linear regression as y = -0.0003*y + 6.7076 (p < 0.0001). Accepting this association between increased elective procedures and reduced AA mortality, each/all 1000 procedures save 0.3 lives per 100,000 inhabitants. CONCLUSION: Despite increasing numbers of AR for AA and AD, only the mortality rate for all AAs decreased, while we did not observe a decrease in overall mortality of AD in Germany.

Thrombectomy in ischemic stroke patients with alberta stroke program early computed tomography score 4-5 and 0-3: Factors associated with favorable outcome.

OBJECTIVES: Recently published results of the ANGEL-ASPECT and SELECT2 trials suggest that stroke patients presenting with low Alberta Stroke Program Early Computed Tomography Score (ASPECTS) benefit from mechanical thrombectomy. Purpose of this retrospective study was to identify factors that are associated with a favorable outcome in patients with low ASPECTS of 4-5 and 0-3 undergoing mechanical thrombectomy. MATERIAL AND METHODS: All patients reported in the quality registry of the German Society for Neuroradiology that were treated between 2018 and 2020 were analyzed. Favorable outcome was defined as a National Institute of Health Stroke Scale (NIHSS) score of less than 9 at dismissal. Successful recanalization was defined as Thrombolysis in Cerebral Infarction (mTICI) ≥ 2b. Multivariable logistic regression analyses were performed to assess the association of baseline and treatment variables with favorable outcome. RESULTS: 621 patients were included in the analysis, thereof 495 with ASPECTS 4-5 and 126 with ASPECTS 0-3. In patients with ASPECTS 4-5patients with favorable outcome had less severe neurological symptoms at admission with median NIHSS of 15 vs. 18 (p<0.001), had less often wake-up strokes (44% vs. 81%, p<0.001), received more often iv-lysis (37% vs. 30%, p<0.001), had more often conscious sedation (29% vs. 16%, p<0.001), had a higher rate of successful recanalization (94% vs. 66% and lower times from groin puncture to recanalization. In multivariate regression analysis lower NIHSS at admission (aOR 0.87, CI 0.89-0.91) and successful recanalization (aOR 3.96, CI 2-8.56) were associated with favorable outcome. For ASPECTS 0-3, patients with favorable outcome had lower median NIHSS at admission (16 vs. 18 (p<0.001), lower number of passes (1 vs. 3, p=0.003) and a higher rate of successful recanalization (94% vs. 66%, p<0.001) and lower times from groin puncture to recanalization. In multivariate regression analysis lower NIHSS at admission (aOR 0.87, CI 0.81-0.94) and successful recanalization, (aOR 11.19, CI 3.19-55.53), were associated with favorable outcome. CONCLUSION: Full recanalization with low groin punction to recanalization times and low number of passes were associated with favorable outcome in patients with low ASPECTS.

Radiation Dose in Prostatic Artery Embolization Using Cone-Beam CT and 3D Roadmap Software.

PURPOSE: To evaluate the radiation dose in patients undergoing prostatic artery embolization (PAE) using cone-beam CT and 3-dimensional (3D) guidance software. MATERIALS AND METHODS: In this single-center retrospective study, 100 patients with benign prostatic hyperplasia (mean prostate volume, 83.6 mL ± 44.2; 69.4 ± 9.6 years of age; body mass index, 26.5 ± 4.2) were treated using PAE between October 2016 and April 2018. Informed consent was obtained from all participants included in the study. All patients received at least 1 intraprocedural cone-beam CT per side for evaluation of the vessel anatomy and software rendering of 3D guidance for catheter guidance. Digital subtraction angiography (DSA) was performed in the distal branches only. The total dose area product (DAP), along with the DAP attributed to fluoroscopy, DSA, and cone-beam CT, were assessed. RESULTS: Bilateral embolization was achieved in 83 patients (83%). The average total DAP was 134.4 Gy ⋅ cm2 ± 69.5 (range, 44.7-410.9 Gy ⋅ cm2). Fluoroscopy, DSA, and cone-beam CT accounted for 35.5 Gy ⋅ cm2 ± 21.3 (range, 8.6-148.6 Gy ⋅ cm2) or 26.4% (percentage of total DAP), 58.2 Gy ⋅ cm2 ± 48.3 (range, 10.3-309.3 Gy ⋅ cm2) or 43.3%, and 40.7 Gy ⋅ cm2 ± 14.5 (range, 15.9-86.3 Gy ⋅ cm2) or 30.3%, respectively. Average procedure time was 89.4 ± 27.0 minutes, and the average fluoroscopy time was 30.9 ± 12.2 minutes. CONCLUSIONS: Intraprocedural cone-beam CT in combination with 3D guidance software allows for identification and catheterization of the prostatic artery in PAE. Furthermore, the results of this trial indicate that this study protocol may lead to a low overall radiation dose.

Presepsin and Inflammatory Markers Correlate With Occurrence and Severity of Nonocclusive Mesenteric Ischemia After Cardiovascular Surgery.

OBJECTIVES: To prospectively evaluate the relationship of established inflammatory markers and presepsin on nonocclusive mesenteric ischemia and to correlate presepsin levels to the occurrence and severity of nonocclusive mesenteric ischemia. DESIGN: Patients were prospectively enrolled and blood samples taken, followed by a retrospective evaluation of laboratory values and angiographic findings. The study was ethics committee approved. SETTINGS: Patients with clinical suspicion of nonocclusive mesenteric ischemia underwent catheter angiography of the superior mesenteric artery. Images were assessed by two experienced radiologists on consensus basis using a previously published standardized reporting system (Homburg-Nonocclusive Mesenteric Ischemia-Score). Two groups were formed according to the severity of nonocclusive mesenteric ischemia, mild and severe, patients without clinical signs of nonocclusive mesenteric ischemia formed the reference group. These data were correlated to inflammatory blood markers assessed pre- and postoperatively: C-reactive protein, leucocytes, procalcitonin, and presepsin as well as outcome data. PATIENTS: Between January 2010 and March 2011, a total of 839 patients undergoing cardiovascular surgery participated in this study. MEASUREMENTS AND MAIN RESULTS: Mild nonocclusive mesenteric ischemia was diagnosed in 4.5%, and severe nonocclusive mesenteric ischemia in 3.2%. Median postoperative presepsin concentrations were significantly greater in mild and severe nonocclusive mesenteric ischemia than in non-nonocclusive mesenteric ischemia. Statistics showed that postoperative presepsin better discriminated mild and severe nonocclusive mesenteric ischemia than any other tested biomarker. CONCLUSIONS: Elevated postoperative plasma presepsin concentrations are an independent predictor of mild and severe nonocclusive mesenteric ischemia. The established inflammatory blood markers significantly correlate with the development and severity of nonocclusive mesenteric ischemia.

Mortality in endovascular and open abdominal aneurysm repair - trends in Germany.

BACKGROUND: We analysed trends in mortality of endovascular (EVAR) and open aortic repair (OAR) in patients hospitalized for abdominal aortic aneurysms (AAA) in Germany from 2005 to 2015. PATIENTS AND METHODS: We used national statistics published by the Federal Statistical Office in Germany to calculate mortality rate of patients hospitalized with ruptured (rAAA, n = 2,448 in 2005, n = 2,180 in 2015) and non-ruptured (iAAA, n = 11,626 in 2005, n = 14,205 in 2015) AAA. RESULTS: Considering only those who were treated with EVAR or OAR, treatment rates of iAAA with EVAR increased to 78.2 % in males and 72.6 % in females in 2015 and treatment rates of rAAA to 36.9 % and 40.7 %, respectively. In cases with iAAA, death rates associated with EVAR decreased in males from 2.1 to 1.1 % (p = 0.0005) in the period from 2005 to 2015 but not in females (1.8 % in 2005 and 2.3 % in 2015, p = 0.8511). Similar trends are seen in cases with rAAA (males 30.1 % and 24 %, p = 0.1034, females 36.4 to 37.3 %, p = 0.8511). Death rates associated with OAR increased in males from 4.7 % in 2005 to 5.7 % in 2015 (p = 0.0103) and tended to increase in females from 6.8 to 8.2 % (p = 0.1476). In cases of rAAA, there were no changes. EVAR treatment rates increased in cases with iAAA in both genders with age, as well as in males with rAAA, but not in females. OAR associated death rates increased with age in rAAA (from around 30 % in the sixth/seventh decade of life to almost 80 % in cases with patients over the age of 90) and in iAAA (from 1.1 to 20 %). CONCLUSIONS: The general increase in EVAR procedures in males and females hospitalized for rAAA and iAAA went along with a decrease in in-hospital mortality in males treated with EVAR for iAAA only and an increasing mortality in males treated with OAR for iAAA.

Endovascular treatment of renal artery stenosis in Germany: a retrospective analysis of the DEGIR registry 2018-2021.

PURPOSE: To provide an overview of endovascular treatment of renal artery stenosis (RAS) using the data of the Deutsche Gesellschaft für interventionelle Radiologie (DeGIR) quality management system. MATERIALS AND METHODS: A retrospective analysis was performed. Pre-, peri- and postprocedural data, technical success rates, complication rates, and clinical success rates at dismissal were examined. RESULTS: Between 2018 and 2021, 2134 angiography examinations of the renal arteries were performed: diagnostic angiography in 70 patients (3 %), balloon angioplasty in 795 (37 %), stent implantation in 1166 (55 %) and miscellaneous procedures in 103 (5 %). The lesion length was less than or equal to 5 mm in 1837 patients (87 %), between 5 and 10 mm in 197 (9 %), and between 10 and 20 mm in 62 (3 %). The degree of stenosis was less than 50 % in 156 patients (7 %), greater than 50 % in 239 (11 %), and greater than 70 % in 1472 (70 %). Occlusion was treated in 235 patients (11 %). Symptoms at discharge resolved in 600 patients (29 %), improved in 1012 (49 %), were unchanged in 77 (4 %), and worsened in 5 (0.2 %). Complications were reported in 51 patients (2.5 %) and the mortality rate was 0.15 %. CONCLUSION: A substantial number of patients with RAS and occlusions were treated by radiologists in Germany, with high technical success rates and low complication rates. The indication should be determined carefully as the current European guidelines for the treatment of RAS suggest that only carefully selected groups of patients will benefit from recanalizing treatment. KEY POINTS: · Carefully selected patient groups may benefit from endovascular treatment of renal artery stenosis.. · Analysis of the DEGIR quality management database shows that treatment of renal artery stenosis was performed by radiologists in Germany with high technical success rates and low complication rates.. · Recanalization even led to symptom improvement in a large proportion of patients with occlusions..

The status of academic interventional radiologists in Germany with focus on gender disparity: how can we do better?

PURPOSE: The aim was to characterize the framework conditions in academic interventional radiology (IR) in Germany with focus on differences between genders. MATERIALS AND METHODS: After IRB approval, all members of The German Society for Interventional Radiology and Minimally Invasive Therapy (n = 1,632) were invited to an online survey on work and research. Statistical comparisons were undertaken with the Fisher's exact test, Wilcoxon rank sum test or Pearson's Chi-squared test. RESULTS: From 267 available questionnaires (general response rate 16.4%), 200 were fully completed. 40% of these (78/200) were involved in research (71% men vs. 29% women, p < 0.01) and eligible for further analysis. Of these, 6% worked part-time (2% vs. 17%, p < 0.05). 90% of the respondents spent less than 25% of their research during their paid working hours, and 41% performed more than 75% of their research during. leisure time. 28% received exemption for research. 88% were (rather) satisfied with their career. One in two participants successfully applied for funding, with higher success rates among male applicants (90% vs. 75%) and respondents with protected research time (93% vs. 80%). Compared to men, women rated their entrance in research as harder (p < 0.05), their research career as more important (p < 0.05), felt less noticed at congresses (93% vs. 53%, p < 0.01), less confident (98% vs. 71%, p < 0.01), and not well connected (77% vs. 36%, p < 0.01).  CONCLUSION: Women and men did research under the same circumstances; however, women were underrepresented. Future programs should generally focus on protected research time and gather female mentors to advance academic IR in Germany.

Detection of coronary plaques using MR coronary vessel wall imaging: validation of findings with intravascular ultrasound.

OBJECTIVES: Compared with X-ray coronary angiography (CAG), magnetic resonance imaging of the coronary vessel wall (MR-CVW) may provide more information about plaque burden and coronary remodelling. We compared MR-CVW with intravascular ultrasound (IVUS), the standard of reference for coronary vessel wall imaging, with regard to plaque detection and wall thickness measurements. METHODS: In this study 17 patients with chest pain, who had been referred for CAG, were included. Patients underwent IVUS and MR-CVW imaging of the right coronary artery (RCA). Subsequently, the coronary vessel wall was analysed for the presence and location of coronary plaques. RESULTS: Fifty-two matching RCA regions of interest were available for comparison. There was good agreement between IVUS and MR-CVW for qualitative assessment of presence of disease, with a sensitivity of 94% and specificity of 76%. Wall thickness measurements demonstrated a significant difference between mean wall thickness on IVUS and MR-CVW (0.48 vs 1.24 mm, P < 0.001), but great heterogeneity between wall thickness measurements, resulting in a low correlation between IVUS and MR-CVW. CONCLUSIONS: MR-CVW has high sensitivity for the detection of coronary vessel wall thickening in the RCA compared with IVUS. However, the use of MRI for accurate absolute wall thickness measurements is not supported when a longitudinal acquisition orientation is used.

Liver fibrosis: how many samples in transjugular liver biopsy are sufficient? Histological vs. clinical value.

PURPOSE: Liver biopsy (LB) is a diagnostic procedure to obtain histological diagnosis, grading and staging in individuals with liver diseases. Most commonly LB is performed percutaneously. However, transjugular liver biopsy (TJLB) is considered as an alternative. The aim of this prospective study was to evaluate the diagnostic accuracy of TJLB. METHODS: TJLB with a semi-automatic Tru-Cut System (18G) was performed in 39 patients with various liver diseases (21 females and 18 males; age range 11-77 years). The number of complete portal tracts (CPTs), lengths and numbers of acquired cores, number of performed cutting steps (passes), and the possibility to obtain histological diagnosis were analyzed. RESULTS: There were no procedure-related complications, and in total 45 procedures were performed. Diagnosis could be established in 88.8 % of all samples, in five cases histology yielded no diagnosis due to an inadequate number of CPTs or sample fragmentation. In average, 4 passes were performed and 4 (range 1-7) cores were obtained. Median core length was 1.1 cm (range 0.4-1.9 cm), median number of CPTs was 7 (range 0-20). Liver fibrosis in general led to a decreased number of CPTs (p < 0.05). CONCLUSIONS: TJLB is a safe procedure allowing histological diagnosis of liver diseases. In our cohort, performing 4 cutting procedures during TJLB resulted in a sufficiently high specimen quality, particularly in individuals with liver cirrhosis.

How to Treat Type B Aortic Dissections in the Presence of an Aberrant Right Subclavian Artery: A Systematic Review.

An aberrant right subclavian artery (ARSA) is the most common congenital variant of the aortic arch. Usually, this variation is largely asymptomatic, but sometimes it may be involved in aortic dissection (AD). Surgical management of this condition is challenging. The therapeutic options have been enriched in recent decades by establishing individualized endovascular or hybrid procedures. Whether these less invasive approaches bear advantages, and how they have changed the treatment of this rare pathology, is still unclear. Therefore, we conducted a systematic review. We performed a review of literature from the past 20 years (from January 2000 until February 2021) complying with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. All reported patients treated for Type B AD in the presence of an ARSA were identified and classified into three groups according to the received therapy (open, hybrid, and total endovascular). Patient characteristics, as well as in-hospital mortality, and major and minor complications were determined and statistically analyzed. We identified 32 relevant publications comprising 85 patients. Open arch repair has been offered to younger patients, but significantly less often in symptomatic patients needing urgent repair. Therefore, the maximum aortic diameter was also significantly larger in the open repair group compared with that in the hybrid or total endovascular repair group. Regarding the endpoints, we did not find significant differences. The literature review revealed that open surgical therapies are preferred in patients presenting with chronic dissections and larger aortic diameters, most likely because they are unsuitable for endovascular aortic repair. Hybrid and total endovascular approaches are more often applied in emergency situations, where aortic diameters remain smaller. All therapies demonstrated good, early, and midterm outcomes. But, these therapies carry potential risks in the long term. Therefore, long-term follow-up data are urgently needed to validate that these therapies are sustainable.

Outcome prediction prior to thrombectomy of the posterior circulation with machine learning.

PURPOSE: Various studies have identified prognostic factors for a favorable outcome of endovascular treatment in posterior circulation. We evaluated various machine learning algorithms in their ability to classify between patients with favorable (defined as 0-2 points on the modified Rankin scale [mRS]), unfavorable (mRS 3-6), poor (mRS 5-6), and nonpoor (mRS 0-4) outcomes at dismissal. METHODS: We retrospectively analyzed data from 415 patients that were treated between 2018 and 2021 from the multicentric DGNR registry. Five models (random forest, support vector machine, k-nearest neighbor, neural network [NN], and generalized linear model [GLM]) were trained with clinical input variables and evaluated with a test dataset of 82 patients. The model with the highest accuracy on the training dataset was defined as the best model. RESULTS: A total of 132 patients showed poor and 162 patients showed favorable outcome. All baseline variables except sex were highly significantly different between patients with favorable and unfavorable outcomes. The variables NIHSS, the presence of wake-up stroke, the administration of IV-thrombolysis and mRS pretreatment were significantly different between patients with poor and nonpoor outcomes. The best-performing NN achieved a sensitivity of 0.56, a specificity of 0.86 and an area under the curve (AUC) of 0.77 on the test dataset in the classification analysis between favorable and unfavorable outcomes. The best-performing GLM achieved a sensitivity of 0.65, a specificity of 0.91 and an AUC of 0.81 in the classification analysis between poor and nonpoor outcomes. CONCLUSION: Short-term favorable and poor outcomes in patients with acute ischemic stroke of the posterior circulation can be predicted prior to thrombectomy with moderate sensitivity and high specificity with machine learning models.

Machine learning based prediction of length of stay in acute ischaemic stroke of the anterior circulation in patients treated with thrombectomy.

BACKGROUND: Length of stay is an important factor for managing the limited resources of a hospital. The early, accurate prediction of hospital length of stay leads to the optimized disposition of resources particularly in complex stroke treatment. OBJECTIVE: In the present study we evaluated different machine learning techniques in their ability to predict the length of stay of patients with stroke of the anterior circulation who were treated with thrombectomy. MATERIAL AND METHODS: This retrospective study evaluated four algorithms (support vector machine, generalized linear model, K-nearest neighbour and Random Forest) to predict the length of hospitalization of 113 patients with acute stroke who were treated with thrombectomy. Input variables encompassed baseline data at admission, as well as periprocedural and imaging data. Ten-fold cross-validation was used to estimate accuracy. The accuracy of the algorithms was checked with a test dataset. In addition to regression analysis, we performed a binary classification analysis to identify patients that stayed longer than the mean length of stay. RESULTS: Mean length of stay was 10.7 days (median 10, interquartile range 6-15). The sensitivity of the best-performing Random Forest model was 0.8, the specificity was 0.68 and the area under the curve was 0.73 in the classification analysis. The mean absolute error of the best-performing Random Forest Model was 4.6 days in the test dataset in the regression analysis. CONCLUSION: Machine learning has potential use to estimate the length of stay of patients with acute ischaemic stroke that were treated with thrombectomy.

Feasibility of Network-Based, Online Endovascular Simulator Training in Real Time: Results from a Pilot Study.

PURPOSE: To test the feasibility of an online, simulator-based comprehensive interventional radiology (IR) training curriculum in times of COVID-19-induced travel restrictions. MATERIALS AND METHODS: A network of six VIST simulators (Mentice, Gothenburg, Sweden) was installed in six geographically different radiology departments. Two courses with six sessions each took place. 43 participants were recruited on a voluntary basis among local residents. The training sessions were conducted in real time with interconnected simulation devices and were led by experts in the field of IR on a rotational basis. The participants attitude toward various topics was quantified before and after training on a seven-point Likert scale (1 = "not at all", 7 = "to the highest degree"). In addition, post-course surveys were conducted. RESULTS: The courses led to an improvement for all items compared with baseline: interest in IR (pre: 5.5, post: 6.1), knowledge of endovascular procedures (pre: 4.1, post: 4.6), likelihood of choosing IR as a subspecialty (pre: 5.7, post: 5.9). Experience with endovascular procedures (pre: 3.7, post: 4.6) improved significantly (p = 0.016). In the post-course surveys high satisfaction rates with the pedagogical approach (mean 6), the teaching content (mean 6.4), and the duration and frequency of the course (mean 6.1) were observed. CONCLUSION: The implementation of a simultaneous endovascular online training curriculum in different geographic locations is feasible. The curriculum has the potential to meet the demand for training in IR in times of COVID-19-associated travel restrictions and can complement future training in the context of radiologic congresses. KEY POINTS: · The implementation of a simultaneous endovascular online training curriculum in different geographic locations is feasible. For interested residents, the presented online curriculum can offer a low-threshold and comprehensive entry into the world of interventional radiology at the site of their training..

Thrombectomy of Mild Stroke : An Analysis of the Nationwide Registry of the German Society for Neuroradiology.

PURPOSE: Whether patients presenting with mild stroke (NIHSS at admission < 6) should be treated with mechanical thrombectomy (MT) is the subject of an ongoing debate. This retrospective study based on large-scale clinical data aims to identify factors associated with favorable outcome (FO) in patients with mild stroke. METHODS: A total of 761 patients with mild stroke enrolled between 1 January 2020 and 31 December 2020 in the Quality Registry of the German Society for Neuroradiology were analyzed. The FO was defined as stable or improved NIHSS at discharge vs. admission. Descriptive statistics and multivariable logistic regression analyses were performed to identify factors associated with FO. Furthermore, a subgroup analysis of mild stroke based on distal vessel occlusion was conducted. RESULTS: In this study 610 patients had FO with a median NIHSS at discharge of 1 (interquartile range, IQR, 0-2) and 151 had an unfavorable outcome (UO) with median NIHSS at discharge of 10 (IQR 13). Patients with FO had a slightly higher NIHSS at admission (4 vs. 3, p < 0.001), lower mTICI 0 (2.7% vs. 14.2%, p < 0.001), higher mTICI 3 (61.3% vs. 34.5%, p < 0.001) and a lower number of passes (1 vs. 2, p < 0.001). No statistically significant difference was observed for MT-related adverse events. Multivariable logistic regression suggested that NIHSS at admission (adjusted odds ratio (aOR) = 1.28, 95% confidence interval (CI) = 1.10-1.48), mTICI 2b (aOR = 5.44, CI = 2.06-15.03), mTICI 2c (aOR = 10.81, CI = 3.65-34.07) and mTICI 3 (aOR = 11.56, CI = 4.49-31.10) as well as number of passes (aOR 0.76, CI = 0.66-0.88) were significantly associated with FO. No MT-related adverse events were observed for distal vessel occlusions. CONCLUSION: The FO in patients with mild stroke undergoing MT was associated with successful recanalization. No significant differences between patients with FO and UO were found for MT-related adverse events, suggesting that MT complications have no significant effects on the outcome of these patients. MT might improve the prognosis also in patients with mild stroke based on distal vessel occlusions without significantly increasing the risk of adverse events.

Thin Slice Unenhanced Brain CT Can Detect Aneurysms Larger than 7 mm.

Purpose: To evaluate the detection rate of intracranial aneurysms on reconstructed thin slice non enhanced CT (NECT) scans. Methods: NECT scans from 34 patients with 35 aneurysms and 35 individuals without aneurysms were collected. Thin slice maximum intensity projections of the NECT scans were reconstructed. One observer evaluated the native images twice with a time interval of six month between both passes with respect to the prevalence and location of an aneurysm. The size and location of the aneurysms were evaluated in corresponding CT-Angiography and Time of flight datasets. A logit regression analysis was performed with size and location as dependent variables. 2 × 2 tables were constructed. The sensitivity and false negative rate were calculated for aneurysms with 0-6.9 mm, 7-9.9 mm and 10-20 mm and the under the curve (AUC) was calculated. Results: The overall detection rate of the aneurysms was 63% for the first pass and 66% for the second pass in the reconstructed NECT scans. The detection rate of aneurysms is size dependent. The sensitivity to detect aneurysms with a size of 0-6.9 mm was 0.09 and 0.03, for aneurysms with a size of 7-9.9. mm was 0.8 and 0.7 and for aneurysms with a size of 10-20 mm was 0.92 for both passes.The AUC was 0.77 for the first pass and 0.78 for the second pass. Conclusions: NECT scans can be used to detect a significant proportion of intracranial aneurysms larger than 7 mm if properly displayed and reconstructed. These patients should receive further vascular imaging to prevent future aneurysm related subarachnoid hemorrhage.

Quantification of periaortic adipose tissue in contrast-enhanced CT angiography: technical feasibility and methodological considerations.

To examine the feasibility of the quantification of abdominal periaortic fat tissue (PaFT) (tissue within - 45 to - 195 HU) in enhanced CT-angiographies compared to unenhanced CT-scans and identify methodological issues affecting its clinical implementation. Using OsirixMD, PaFT volume and mean HU value were retrospectively measured within a 5 mm periaortic ring in paired unenhanced and enhanced abdominal aortic CT-scans. The correlation between PaFT values was examined in a derivation cohort (n = 101) and linear regression analysis produced correction factors to convert values from enhanced into values from unenhanced CTs. The conversion factors were then applied to enhanced CTs in a different validation cohort (n = 47) and agreement of corrected enhanced values with values from unenhanced scans was evaluated. Correlation between PaFT Volume und Mean HU from enhanced and unenhanced scans was very high (r > 0.99 and r = 0.95, respectively, p < 0.0001 for both). The correction factors for PaFT Volume and Mean HU were 1.1057 and 1.0011. Potential confounding factors (CT-kilovoltage, slice thickness, mean intraluminal contrast density, aortic wall calcification, longitudinal variation of intraluminal contrast density, aortic diameter) showed no significant effect in a multivariate regression analysis (p > 0.05). Bland-Altman analysis of corrected enhanced and unenhanced values showed excellent agreement and Passing-Bablok regression confirmed minimal/no residual bias. PaFT can be quantified in enhanced CT-angiographies very reliably. PaFT Volume scores are very consistently slightly underestimated in enhanced scans by about 10%, while the PaFT Mean HU value remains practically constant and offers distinct methodological advantages. However, a number of methodological issues remain to be addressed.

Machine learning based outcome prediction of large vessel occlusion of the anterior circulation prior to thrombectomy in patients with wake-up stroke.

PURPOSE: Outcome prediction of large vessel occlusion of the anterior circulation in patients with wake-up stroke is important to identify patients that will benefit from thrombectomy. Currently, mismatch concepts that require MRI or CT-Perfusion (CTP) are recommended to identify these patients. We evaluated machine learning algorithms in their ability to discriminate between patients with favorable (defined as a modified Rankin Scale (mRS) score of 0-2) and unfavorable (mRS 3-6) outcome and between patients with poor (mRS5-6) and non-poor (mRS 0-4) outcome. METHODS: Data of 8395 patients that were treated between 2018 and 2020 from the nationwide registry of the German Society for Neuroradiology was retrospectively analyzed. Five models were trained with clinical variables and Alberta Stroke Program Early CT Score (ASPECTS). The model with the highest accuracy was validated with a test dataset with known stroke onset and with a test dataset that consisted only of wake-up strokes. RESULTS: 2419 patients showed poor and 3310 patients showed favorable outcome. The best performing Random Forest model achieved a sensitivity of 0.65, a specificity of 0.81 and an AUC of 0.79 on the test dataset of patients with wake-up stroke in the classification analysis between favorable and unfavorable outcome and a sensitivity of 0.42, a specificity of 0.83 and an AUC of 0.72 in the classification analysis between poor and non-poor outcome. CONCLUSION: Machine learning algorithms have the potential to aid in the decision making for thrombectomy in patients with wake-up stroke especially in hospitals, where emergency CTP or MRI imaging is not available.

Value of machine learning to predict functional outcome of endovascular treatment for acute ischaemic stroke of the posterior circulation.

PURPOSE: Clinical outcomes vary considerably among individuals with vessel occlusion of the posterior circulation. In the present study we evaluated machine learning algorithms in their ability to discriminate between favourable and unfavourable outcomes in patients with endovascular treatment of acute ischaemic stroke of the posterior circulation. METHODS: This retrospective study evaluated three algorithms (generalised linear model, K-nearest neighbour and random forest) to predict functional outcomes at dismissal of 30 patients with acute occlusion of the basilar artery who were treated with thrombectomy. Input variables encompassed baseline as well as peri and postprocedural data. Favourable outcome was defined as a modified Rankin scale score of 0-2 and unfavourable outcome was defined as a modified Rankin scale score of 3-6. The performance of the algorithms was assessed with the area under the receiver operating curve and with confusion matrixes. RESULTS: Successful reperfusion was achieved in 83%, with 30% of the patients having a favourable outcome. The area under the curve was 0.93 for the random forest model, 0.86 for the K-nearest neighbour model and 0.78 for the generalised linear model. The accuracy was 0.69 for the generalised linear model and 0.84 for the random forest and the K nearest neighbour models. CONCLUSION: Favourable and unfavourable outcomes at dismissal of patients with acute ischaemic stroke of the posterior circulation can be predicted immediately after the follow-up non-enhanced computed tomography using machine learning.

Embolization of Hemorrhoidal Arteries: A Novel Endovascular Therapy Option for the Treatment of Hemorrhoidal Disease. / Hämorrhoidenembolisation: Eine neue minimalinvasive endovaskuläre Therapieoption bei Hämorrhoidalleiden.

BACKGROUND: Hemorrhoids are a widespread disease. Treatment options range from dietary measures to open surgery. A novel treatment approach is the embolization of the hemorrhoidal arteries. METHOD: A review was performed based on a selective literature search in PubMed representing the current state of research. The keywords "hemorrhoid" and "embolization" and "emborrhoid" were used. In addition, technical details of the hemorrhoidal embolization procedure are explained. RESULTS AND CONCLUSION: Embolization of hemorrhoidal arteries is a safe treatment, which allows efficient symptom control even in patients with contraindications for open surgery. KEY POINTS: · Embolization of hemorrhoidal arteries is a new approach to the treatment of hemorrhoids.. · Embolization of hemorrhoidal arteries is feasible in patients with contraindications for open surgery such as hypercoaguable states and contraindications for general anesthesia.. · The endovascular approach causes no rectal and anal trauma and associated complications can be avoided.. · The treatment of bleeding hemorrhoids seems to be particularly effective.. · No ischemic complications have been reported so far when coils as well as particles were used.. CITATION FORMAT: · Feyen L, Freyhardt P, Schott P et al. Hämorrhoidenembolisation: Eine neue minimalinvasive endovaskuläre Therapieoption bei Hämorrhoidalleiden. Fortschr Röntgenstr 2022; 194: 266 - 271.

Nationwide Provision of Radiologically-guided Interventional Measures for the Supportive Treatment of Tumor Diseases in Germany - An Analysis of the DeGIR Registry Data. / Flächendeckende Versorgung mit radiologisch-interventionellen supportiven Maßnahmen bei Tumorerkrankungen und anderen Erkrankungen (DeGIR-Modul C) in Deutschland ­ Eine Analyse der DeGIR-Registerdaten.

PURPOSE: In addition to direct oncologic therapy, interventional radiology plays an important supportive role in oncologic therapy primarily guided by other disciplines. These supporting measures include diagnostic punctures, drainages, biliary interventions, central venous access including port implantations, osteoplasties, pain therapies etc.). This study investigated the extent to which these radiologically guided supportive measures are available in Germany. MATERIAL AND METHODS: All interventional procedures documented in the DeGIR-registry (excluding transhepatic portosystemic shunts) of the years 2018 and 2019 were recorded (DeGIR-module C). A breakdown of the documented interventions was performed based on federal states as well as 40 individual regions (administrative districts and former administrative districts). RESULTS: A total of 136,328 procedures were recorded at 216 centers in DeGIR Module C in 2018 and 2019. On average, 389 cases were documented per hospital in 2018 and 394 cases in 2019; the increase per hospital from 2019 is not statistically significant but is relevant in the aggregate when new participating centers are included, with an overall increase of 10 % (6,554 more cases than the previous year). Normalized to one million inhabitants, an average of 781 procedures took place across Germany in 2018 and 860 in 2019. Districts with no registered procedures are not found for Module C.Indications for Module C interventions were mostly interdisciplinary in 2018 and 2019. In this context, the quality of outcome was very high; for the procedures drain placement, marking and biopsy the technical success was 99 %, while the complication rate was lower than 1 %. CONCLUSION: The structural analysis of this work concludes that in Germany there is good nationwide availability of radiologically guided supportive measures in oncological therapy. Accordingly, the training situation for prospective interventional radiologists is good, as the distribution to centers with high experience is excellent. In addition, the overall outcome quality of radiology-guided interventions is very high. KEY POINTS: · In Germany, there is good nationwide coverage of radiologically guided supportive interventions in oncological therapy.. · The training situation for prospective interventional radiologists is good, as the distribution to centers with high experience is excellent.. · The overall outcome quality of radiology-guided interventions is very high.. CITATION FORMAT: · Nadjiri J, Schachtner B, Bücker A et al. Nationwide Provision of Radiologically-guided Interventional Measures for the Supportive Treatment of Tumor Diseases in Germany - An Analysis of the DeGIR Registry Data. Fortschr Röntgenstr 2022; 194: 993 - 1002.