Automated assessment of cardiac pathologies on cardiac MRI using T1-mapping and late gadolinium phase sensitive inversion recovery sequences with deep learning.

BACKGROUND: A deep learning (DL) model that automatically detects cardiac pathologies on cardiac MRI may help streamline the diagnostic workflow. To develop a DL model to detect cardiac pathologies on cardiac MRI T1-mapping and late gadolinium phase sensitive inversion recovery (PSIR) sequences were used. METHODS: Subjects in this study were either diagnosed with cardiac pathology (n = 137) including acute and chronic myocardial infarction, myocarditis, dilated cardiomyopathy, and hypertrophic cardiomyopathy or classified as normal (n = 63). Cardiac MR imaging included T1-mapping and PSIR sequences. Subjects were split 65/15/20% for training, validation, and hold-out testing. The DL models were based on an ImageNet pretrained DenseNet-161 and implemented using PyTorch and fastai. Data augmentation with random rotation and mixup was applied. Categorical cross entropy was used as the loss function with a cyclic learning rate (1e-3). DL models for both sequences were developed separately using similar training parameters. The final model was chosen based on its performance on the validation set. Gradient-weighted class activation maps (Grad-CAMs) visualized the decision-making process of the DL model. RESULTS: The DL model achieved a sensitivity, specificity, and accuracy of 100%, 38%, and 88% on PSIR images and 78%, 54%, and 70% on T1-mapping images. Grad-CAMs demonstrated that the DL model focused its attention on myocardium and cardiac pathology when evaluating MR images. CONCLUSIONS: The developed DL models were able to reliably detect cardiac pathologies on cardiac MR images. The diagnostic performance of T1 mapping alone is particularly of note since it does not require a contrast agent and can be acquired quickly.

Influence of a 7-day Transalpine Trail Run on cardiac biomarkers and myocardial function.

Intense physical exercise is known to increase cardiac biomarkers; however, it is unclear, whether this phenomenon is physiological, or if it indicates myocardial tissue injury. The aim of our study was to investigate the effects of seven consecutive days of excessive endurance exercise on continuous assessment of cardiac biomarkers, function, and tissue injury. During a 7-day trail-running competition (Transalpine Run, distance 267.4 km, altitude ascent/descent 15556/14450 m), daily blood samples were obtained for cardiac biomarkers (hs-TnT, NT-proBNP, and suppression of tumorigenicity-2 protein (ST2)) at baseline, after each stage and 24-48 h post-race. In addition, echocardiography was performed every second day, cardiac magnetic resonance imaging (CMR) before (n = 7) and after (n = 16) the race. Twelve (eight males) out of 17 healthy athletes finished all seven stages (average total finish time: 43 ± 8 h). Only NT-proBNP increased significantly (3.6-fold, p = 0.009) during the first stage and continued to increase during the race. Hs-TnT revealed an incremental trend during the first day (2.7-fold increase, p = 0.098) and remained within the pathological range throughout the race. ST2 levels did not change during the race. All cardiac biomarkers completely returned to physiological levels post-race. NT-proBNP kinetics correlated significantly with mild transient reductions in right ventricular function (assessed by TAPSE, tricuspid annular plane systolic function; r = -0.716; p = 0.014). No significant echocardiographic changes in LV dimensions, LV function, or relevant alterations in CMR were observed post-race. In summary, this study shows that prolonged, repetitive, high-volume exercise induced a transient, significant increase in NT-proBNP associated with right ventricular dysfunction without corresponding left ventricular functional or structural impairment.

Transjugular intrahepatic portosystemic shunt creation (TIPS) in the angio-CT-a hybrid intervention with image fusion.

OBJECTIVE: For transjugular intrahepatic portosystemic shunt (TIPS) creation, ultrasound guidance for portal vein puncture is strongly recommended. However, outside regular hours of service, a skilled sonographer might be lacking. Hybrid intervention suites combine CT imaging with conventional angiography allowing to project 3D information into the conventional 2D imaging and further CT-fluoroscopic puncture of the portal vein. The purpose of this study was to assess whether TIPS using angio-CT facilitates the procedure for a single interventional radiologist. METHODS: All TIPS procedures from 2021 and 2022 which took place outside regular working hours were included (n = 20). Ten TIPS procedures were performed with just fluoroscopy guidance and ten procedures using angio-CT. For the angio-CT TIPS, a contrast-enhanced CT was performed on the angiography table. From the CT, a 3D volume was created using virtual rendering technique (VRT). The VRT was blended with the conventional angiography image onto the live monitor and used as guidance for the TIPS needle. Fluoroscopy time, area dose product, and interventional time were assessed. RESULTS: Hybrid intervention with angio-CT did lead to a significantly shorter fluoroscopy time and interventional time (p = 0.034 for both). Mean radiation exposure was significantly reduced, too (p = 0.04). Furthermore, the mortality rate was lower in patients who underwent the hybrid TIPS (0% vs 33%). CONCLUSION: TIPS procedure in angio-CT performed by only one interventional radiologist is quicker and reduces radiation exposure for the interventionalist compared to mere fluoroscopy guidance. The results further indicate increased safety using angio-CT. CLINICAL RELEVANCE STATEMENT: This study aimed to evaluate the feasibility of using angio-CT in TIPS procedures during non-standard working hours. Results indicated that the use of angio-CT significantly reduced fluoroscopy time, interventional time, and radiation exposure, while also leading to improved patient outcomes. KEY POINTS: • Image guiding such as ultrasound is recommended for transjugular intrahepatic portosystemic shunt creation but might be not available for emergency cases outside of regular working hours. • Transjugular intrahepatic portosystemic shunt creation using an angio-CT with image fusion is feasible for only one physician under emergency settings and results in lower radiation exposure and faster procedures. • Transjugular intrahepatic portosystemic shunt creation using an angio-CT with image fusion seems to be safer than using mere fluoroscopy guidance.

Efficacy of ultrasound assisted catheter-directed thrombolysis compared to catheter-directed thrombolysis in vitro.

BACKGROUND: Catheter-directed thrombolysis (CDT) is an effective and safe endovascular method used in critical limb ischemia and many other thromboembolic events. Ultrasound-assisted catheter-directed thrombolysis (US-CDT) is an emerging technique considered to accelerate thrombolysis and therefore is supposed to improve outcome. PURPOSE: To evaluate the efficacy of US-CDT in comparison to standard CDT in vitro. MATERIAL AND METHODS: A total of 69 sets of human venous blood were evaluated, each comprising a tube just treated with CDT, a tube treated with US-CDT, and a control tube. All tubes were kept under physiological conditions. Except for the controls, in all tubes 5 mg of tissue-type plasminogen activator was administered over the predetermined treatment interval. Thrombus mass was weighted at the end of the lysis intervals at 6 h or 24 h, respectively. RESULTS: CDT led to a mean thrombus reduction of 32% and ultrasound-assisted lysis led to a mean thrombus reduction of 41% (P < 0.001 for both). Thrombus reduction was significantly higher after US-CDT compared to CDT (P = 0.001). The better efficacy of US-CDT was mostly already apparent at early phases during thrombolysis and did further mildly increase over time (r = 0.24; P = 0.047). CONCLUSION: In vitro US-CDT is significantly superior to standard CDT; this effect is apparent at an early timepoint of lysis and slightly further increases over time.

Calcium scoring using virtual non-contrast images from a dual-layer spectral detector CT: comparison to true non-contrast data and evaluation of proportionality factor in a large patient collective.

OBJECTIVE: Determination of coronary artery calcium scoring (CACS) in non-contrast computed tomography (CT) images has been shown to be an important prognostic factor in coronary artery disease (CAD). The objective of this study was to evaluate the accuracy of CACS from virtual non-contrast (VNC) imaging generated from spectral data in comparison to standard (true) non-contrast (TNC) imaging in a representative patient cohort with clinically approved software. METHODS: One hundred three patients referred to coronary CTA with suspicion of CAD were investigated on a dual-layer spectral detector CT (SDCT) scanner. CACS was calculated from both TNC and VNC images by software certified for medical use. Patients with a CACS of 0 were excluded from analysis. RESULTS: The mean age of the study population was 61 ± 11 years with 48 male patients (67%). Inter-quartile range of clinical CACS was 22-282. Correlation of measured CACS from true- and VNC images was high (0.95); p < 0.001. The slope was 3.83, indicating an underestimation of VNC CACS compared to TNC CACS by that factor. Visual analysis of the Bland-Altman plot of CACS showed good accordance with both methods after correction of VNC CACS by the abovementioned factor. CONCLUSIONS: In clinical diagnostics of CAD, the determination of CACS is feasible using VNC images generated from spectral data obtained on a dual-layer spectral detector CT. When multiplied by a correction factor, results were in good agreement with the standard technique. This could enable radiation dose reductions by obviating the need for native scans typically used for CACS. KEY POINTS: • Calcium scoring is feasible from contrast-enhanced CT images using a dual-layer spectral detector CT scanner. • When multiplied by a correction factor, calcium scoring from virtual non-contrast images shows good agreement with the standard technique. • Omitting native scans for calcium scoring could enable radiation dose reduction.

[Comparison of radiation exposure in common hepatic interventions : A retrospective analysis of DeGIR registry data]. / Strahlenexposition bei häufigen interventionellen Eingriffen der Leber im Vergleich : Retrospektive Analyse von DeGIR-Registerdaten.

BACKGROUND: Transcatheter arterial chemoembolization (TACE) and biliary interventions are common procedures. OBJECTIVES: In this retrospective study, the radiation exposure of patients undergoing hepatic intervention will be analyzed and compared depending on the type and objective of the intervention. MATERIALS AND METHODS: This is an analysis of 7003 data sets of performed TACEs and biliary interventions from the DeGIR registry for the years 2016, 2017, and 2018. The dose area product (DAP), fluoroscopy time (FT), type of intervention, and anatomically defined target were recorded. RESULTS: Data with documented radiation doses were available for 4985 TACEs and for 2018 biliary interventions. For biliary interventions the median DAP was 2594 (interquartile range [IQR] = 1174-5858) cGycm2. For TACE, the median DAP was 11,632 [IQR = 5530-22,800] cGycm2 and significantly higher compared to biliary interventions (p < 0.0001). Biliary interventions with the highest DAP take place at the common hepatic duct; procedures with the longest FT were registered at the hepatic duct bifurcation. CONCLUSIONS: The individual radiation exposure during liver interventions is less dependent of the complexity of the procedure or the fluoroscopy time, but rather on the type of intervention and the anatomic target. The presented data can help to approximately estimate the radiation exposure in advance when planning an intervention.

Iodine concentration of healthy lymph nodes of neck, axilla, and groin in dual-energy computed tomography.

BACKGROUND: Lymph nodes (LN) are examined in every computed tomography (CT) scan. Until now, an evaluation is only possible based on morphological criteria. With dual-energy CT (DECT) systems, iodine concentration (IC) can be measured which could conduct in an improved diagnostic evaluation of LNs. PURPOSE: To define standard values for IC of cervical, axillary, and inguinal LNs in DECT. MATERIAL AND METHODS: Imaging data of 297 patients who received a DECT scan of the neck, thorax, abdomen-pelvis, or a combination of those in a portal-venous phase were retrospectively collected from the institutional PACS. No present history of malignancy, inflammation, or trauma in the examined region was present. For each examined region, the data of 99 patients were used. The IC of the three largest LNs, the main artery, the main vein, and a local muscle of the examined area was measured, respectively. RESULTS: Normalization of the IC of LNs to the artery, vein, muscle, or a combination of those did not lead to a decreased value-range. The smallest range and confidence interval (CI) of IC was found when using absolute values of IC for each region. Hereby, mean values (95% CI) for IC of LN were found: 2.09 mg/mL (2.00-2.18 mg/mL) for neck, 1.24 mg/mL (1.16-1.33 mg/mL) for axilla, and 1.11 mg/mL (1.04-1.17 mg/mL) for groin. CONCLUSION: The present study suggests standard values for IC of LNs in dual-layer CT could be used to differentiate between healthy and pathological lymph nodes, considering the used contrast injection protocol.

Evaluation of a shortened cardiac MRI protocol for left ventricular examinations: diagnostic performance of T1-mapping and myocardial function analysis.

BACKGROUND: In this study we sought to retrospectively evaluate whether a very brief cardiac magnetic resonance imaging (CMR) protocol sufficiently distinguishes patients with relevant myocardial changes with need for further examination from healthy subjects. METHODS: Patients with clinical indication for CMR (n = 160) were included in the study. Patients were categorized into two groups depending on presence of left ventricular (LV) dysfunction. ROC-analysis was done for results of T1-, T2- mapping and extracellular volume evaluation in patients without LV dysfunction. Binary endpoint was correctly depicted pathology of the conventional qualitative CMR techniques and report. RESULTS: In the patient cohort without LV dysfunction (49%), AUC for T1 mapping was 82% (p < 0.001), 60% for T2 mapping (p = 0.1) and 79% for ECV (p < 0.001). T1 mapping was significantly superior to T2 mapping to rule out left ventricular pathology (p = 0.012). Sensitivity for the combined use of T1 mapping and sBTFE cine imaging was 98%; the negative predictive value was 90%. In 49 patients (30%) full protocol CMR did not provide any additional information; T1 mapping correctly detected 57% of the subjects from this group who would not benefit from additional CMR. CONCLUSION: A shortened CMR protocol comprising T1 mapping and LV-function analysis seems suitable to rule out myocardial alterations. Every third patient of the study population did not benefit from full contrast enhanced CMR. The shortened protocol correctly identified every fifth patient who would not benefit but no relevant pathologic findings with the obligation for treatment were missed.

Long-Standing Cyanosis in Congenital Heart Disease Does not Cause Diffuse Myocardial Fibrosis.

The assumption of the presence of diffuse myocardial fibrosis in long-standing cyanotic congenital heart disease (CHD) inspired us to noninvasively determine the myocardial extracellular volume (ECV) using contrast CMR. T1 maps were measured pre and 10 min after the injection of 0.15 mmol/kg of gadolinium in 25 subjects. Seven patients with long-standing cyanotic CHD and no previous cardiac surgery (aged 16-53 years and oxygen saturations of 69-90%), nine normal subjects (aged 14-49 years), and nine patients with previously cyanotic CHD, who had been corrected by open heart surgery (aged 2 months-58 years, mean 9 years). Late gadolinium enhancement was performed to exclude scar areas. The T1 values were measured in the interventricular septum and in the left lateral or inferior ventricular wall, such that same areas were assessed in every patient in the pre- and post-contrast T1 scan. ECV was calculated according to ΔR1myocardium/ΔR1blood * (1 - hematocrit). Cyanotic patients had significantly lower ECV percentage than the previous cyanotic patients (septum: 22 ± 2.7% vs 35 ± 4.6%, p = 0.002; LV wall: 22 ± 2.2% vs 30 ± 3.7%, p = 0.01, respectively). No significant differences were found between cyanotic patients and normal controls (septum: 22 ± 2.7% vs 24 ± 1.4%, p = 0.44; LV wall: 22 ± 2.2% vs 24 ± 2%, p = 0.57, respectively). Long-standing cyanosis in CHD without cardiac surgery does not cause diffuse myocardial fibrosis or expansion of the myocardial ECV.

Erdheim-Chester disease with bilateral Achilles tendon involvement.

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis with a broad spectrum of organ manifestations, presenting with characteristic radiological and histological findings. Soft tissue manifestations (xanthogranulomas) have been reported to be most commonly found in the region of the orbits. We report bilateral Achilles tendon xanthogramlomas in a 36-year-old male with biopsy-proven and B-RAF V600E-positive ECD. Although rare, ECD should be considered in the differential diagnosis of intratendinous masses.

Retrospective evaluation of interventional radiological treatments for chronic mesenteric ischemia in Germany based on a four-year period of the DeGIR Registry: comparison of outcomes with international quality standards.

PURPOSE: Endovascular treatment has emerged as the gold standard for managing chronic mesenteric ischemia (CMI) resulting from arterial stenosis or occlusion. This study aimed to assess the efficacy and complication rates of continuous interventional radiology treatment for CMI in Germany between 2018 and 2021, comparing these findings with international quality standards. MATERIALS AND METHODS: Data for CMI therapy with stenting and percutaneous transluminal angioplasty (PTA) was obtained from the quality management system of the German Interventional Radiological Society (DeGIR). A total of 3752 endovascular procedures for CMI performed from 2018 to 2021 were documented (PTA: n = 675; stenting: n = 3077). Data was analyzed for technical and clinical success rates, as well as major complication rates. RESULTS: Overall technical and clinical success rates for PTA and stenting procedures were 92.03 %/85.9 % and 98.76 %/96.62 %, respectively. The most common major complications were: arterial occlusion (PTA: 0.73 %; stenting: 0.63), major bleeding (PTA: 1.05 %; stenting: 0.68 %), aneurysm formation (PTA: 0.29 %; stenting: 0.72 %), stent dislodgment (PTA: 0 %; stenting: 0.06 %), and organ failure (PTA: 0.43 %; stenting: 0.96 %). Technical and clinical success rates were higher, while complication rates were lower than the corresponding threshold recommended by the Society of Interventional Radiology for the percutaneous management of chronic mesenteric ischemia. CONCLUSION: Treatment of CMI performed by interventional radiologists in Germany is safe and effective during daily and on-call shifts with results exceeding internationally accepted standards. KEY POINTS: · Treatment of CMI by interventional radiologists in Germany is effective and safe.. · The interventions are safe and effective regardless of whether they are performed during on-call shifts or the daily routine.. · The clinical and technical success rates favorably surpass the thresholds presented by SIR.. · Different major complications occurred in under 1.1 % of CMI interventions..

Assessment of Efficacy and Complications of Endovascular Interventions for Critical Limb Ischemia in Germany: A Nationwide Study.

PURPOSE: Endovascular interventional radiological procedures have become the mainstay for the treatment of critical limb ischemia (CLI) due to arterial stenosis or occlusion. Open surgical or endovascular procedures, such as percutaneous transluminal angioplasty (PTA) or stenting can be used as a treatment strategy. The aim is to evaluate the success and major complication rates of interventional radiology treatments for CLI in Germany in 2021, and to compare these results with internationally published data. MATERIALS AND METHODS: Data for PTA and stenting in CLI for 2021 was obtained from the quality management system of the German Society of Interventional Radiology (DeGIR). 16 393 PTA procedures, 701 stenting procedures, and 8110 combined procedures were documented for 2021. Data was analyzed for technical and clinical success rates, as well as major complication rates documented mainly as major bleeding, distal embolization, and aneurysm formation. RESULTS: PTA had technical and clinical success rates of 96.3 % and 92.33 %, respectively. Stenting had technical and clinical success rates of 98.7 % and 96.15 %, respectively. PTA and stenting combined had success rates of 98.71 % and 96.91 %, respectively. The major complications were mainly: major bleeding (PTA: 0.40 %; stenting: 1.28 %; PTA and stenting: 0.54 %), distal embolization (PTA: 0.48 %; stenting: 1 %; PTA and stenting: 0.96 %), and aneurysm formation (PTA: 0.19 %; stenting: 0.43 %; PTA and stenting: 0.19 %). All procedures showed high technical and clinical success rates, while the complication rates were low. CONCLUSION: Interventional radiologists in Germany perform effective and safe treatment for CLI, achieving outcomes that tend to surpass internationally published data. KEY POINTS: · German interventional radiologists provide safe and effective critical limb ischemia treatment.. · Major complications occurred at maximum in 1.28 % of cases.. · Outcomes tend to surpass international data, indicating strong performance..

Spectral computed tomography angiography using a gadolinium-based contrast agent for imaging of pathologies of the aorta.

OBJECTIVES: Especially patients with aortic aneurysms and multiple computed tomography angiographies (CTA) might show medical conditions which oppose the use of iodine-based contrast agents. CTA using monoenergetic reconstructions from dual layer CT and gadolinium (Gd-)based contrast agents might be a feasible alternative in these patients. Therefore, the purpose of this study was to evaluate the feasibility of clinical spectral CTA with a Gd-based contrast agent in patients with aortic aneurysms. METHODS: Twenty-one consecutive scans in 15 patients with and without endovascular aneurysm repair showing contraindications for iodine-based contrast agents were examined using clinical routine doses (0.2 mmol/kg) of Gd-based contrast agent with spectral CT. Monoenergetic reconstructions of the spectral data set were computed. RESULTS: There was a significant increase in the intravascular attenuation of the aorta between pre- and post-contrast images for the MonoE40 images in the thoracic and the abdominal aorta (p < 0.001 for both). Additionally, the ratio between pre- and post-contrast images was significantly higher in the MonoE40 images as compared to the conventional images with a factor of 6.5 ± 4.5 vs. 2.4 ± 0.5 in the thoracic aorta (p = 0.003) and 4.1 ± 1.8 vs. 1.9 ± 0.5 in the abdominal aorta (p < 0.001). CONCLUSIONS: To conclude, our study showed that Gd-CTA is a valid and reliable alternative for diagnostic imaging of the aorta for clinical applications. Monoenergetic reconstructions of computed tomography angiographies using gadolinium based contrast agents may be a useful alternative in patients with aortic aneurysms and contraindications for iodine based contrast agents.

Safety of sheathless vascular access using braided 4 F selective catheters for common body interventions - a retrospective study.

BACKGROUND: Besides other factors, complication rate of transarterial interventions depends on the size of the vascular access. Therefore, the vascular access is mostly chosen as small as possible while still allowing all planned parts of the intervention. This retrospective analysis is to evaluate the safety and feasibility of sheathless arterial interventions for a broad spectrum of interventions in daily practice. METHODS: All sheathless interventions using a 4 F main catheter between May 2018 and September 2021 were included in the evaluation. Additionally, intervention parameters such as type of catheter, use of microcatheter and required change of main catheters were assessed. Information about the use about sheathless approach and catheters were obtained from the material registration system. All catheters were braided. RESULTS: 503 sheathless interventions with 4 F catheters from the groin were documented. The spectrum comprised bleeding embolization, diagnostic angiographies, arterial DOTA-TATE-therapy, uterine fibroid embolization, transarterial chemotherapy, transarterial radioembolization and others. In 31 cases (6 %) a change of the main catheter was required. In 381 cases (76 %) a microcatheter was utilized. No clinically relevant adverse events were observed (grade 2 or higher [CIRSE AE-classification]). None of the cases later required conversion to a sheath-based intervention. CONCLUSIONS: Sheathless interventions with a 4 F braided catheter from the groin are safe and feasible. It allows for a broad spectrum of interventions in daily practice.

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..

Impact of the COVID-19 Pandemic on Interventional Radiology in Germany. / Auswirkung der COVID-19-Pandemie auf die Interventionelle Radiologie in Deutschland.

PURPOSE: To investigate the effect of the ongoing COVID-19 pandemic on interventional radiology (IR) in Germany in 2020 and 2021. MATERIALS UND METHODS: This retrospective study is based on the nationwide interventional radiology procedures documented in the quality register of the German Society for Interventional Radiology and Minimally Invasive Therapy (DeGIR-QS-Register). The nationwide volume of interventions in the pandemic years 2020 and 2021 was compared with the pre-pandemic period (Poisson-test, Mann-Whitney test). The aggregated data were additionally evaluated by intervention type with differentiated consideration of the temporal epidemiological infection occurrence. RESULTS: During the two pandemic years 2020 and 2021, the number of interventional procedures increased by appr. 4 % compared to the same period of the previous year (n = 190 454 and 189 447 vs. n = 183 123, respectively, p < 0.001). Only the first pandemic wave in spring 2020 (weeks 12-16) showed a significant temporary drop in the number of interventional procedures by 26 % (n = 4799, p < 0.05). This primarily involved interventions that were not immediately medically urgent, such as pain treatments or elective arterial revascularization. In contrast, interventions in the field of interventional oncology, such as port catheter implantations and local tumor ablations, remained unaffected. The decline of the first wave of infection was accompanied by a rapid recovery and a significant, partly compensatory, 14 % increase in procedure numbers in the second half of 2020 compared to the same period of the previous year (n = 77 151 vs. 67 852, p < 0.001). Subsequent pandemic waves had no effect on intervention numbers. CONCLUSION: The COVID-19 pandemic in Germany led to a significant short-term decrease in interventional radiology procedures in the initial phase. A compensatory increase in the number of procedures was observed in the subsequent period. This reflects the adaptability and robustness of IR and the high demand for minimally invasive radiological procedures in medical care. KEY POINTS: · The study shows the nationwide pandemic-related effects on interventional radiology in Germany.. · In quantitative terms, the ongoing pandemic caused a significant, temporary decline in intervention cases only in the initial phase.. · Subsequent waves of infections had no effect on the scope of services provided by interventional radiology.. · Short-term deficits, especially in elective interventions, could be partially compensated.. CITATION FORMAT: · Schmidbauer M, Busjahn A, Paprottka P et al. Impact of the COVID-19 Pandemic on Interventional Radiology in Germany. Fortschr Röntgenstr 2023; 195: 597 - 604.

Safety and efficacy of interventional treatment of acute limb ischemia in Germany 2021.

PURPOSE: Interventional procedures have become a mainstay in the therapy of acute limb ischemia caused by embolism or arterial thrombosis. Treatment options include pharmacological thrombolysis (PT) and mechanical thrombectomy (MT). The aim of this study was to evaluate success and major complication rates of interventional radiological treatments of arterial embolism and thrombosis in Germany in 2021 and to compare their results with accepted international quality standards. MATERIALS AND METHODS: Data for PT and MT for 2021 was obtained from the quality management system of the German interventional radiological society (DeGIR). 2431 PT and 1582 MT procedures were documented for 2021, with 459 combinations of PT and MT. Data was analysed for technical and clinical success rates, as well as major complication rates such as intracranial bleeding, major bleeding, distal embolization, aneurysm formation, organ-failure and cardiac-decompensation. RESULTS: PT alone had technical and clinical success rate of 90.21% and 81.08%, respectively. MT alone had technical and clinical success rates of 97.41% and 95.39%, respectively. MT&PT had technical and clinical success rates of 91.07% and 84.75%, respectively. Major complications were: distal embolization (PT:2.02%; MT:1.74%; PT&MT:2.61%), major bleeding (PT:0.94%; MT:1.14%; PT&MT:0.87%), aneurysm formation (PT:0.33%;MT: 1.14%;PT&MT: 0%), intracranial bleeding (PT:0.16%;MT:0%;PT&MT:0.22%), cardiac-decompensation (PT:0.21%;MT: 0.06%;PT&MT:0%) and organ-failure (PT:0%;MT:0.06%;PT&MT:0.22%). Technical and clinical success rates were higher, while complication rates were lower than the corresponding threshold recommended by the Society of Interventional Radiology for percutaneous management of acute lower-extremity ischemia. CONCLUSION: Treatment of arterial embolism and thrombosis performed by interventional radiologists in Germany is effective and safe with outcomes exceeding internationally accepted standards.

CT-Guided Liver Biopsy: Evaluation of Spectral Data From Dual-Layer Detector CT for Improved Lesion Detection.

PURPOSE: Evaluation of dual-layer spectral computed tomography (CT) for contrast enhancement during image-guided biopsy of liver lesions using virtual monoenergetic images (VMI) and virtual non-contrast (VNC) images. METHODS: Spectral CT data of 20 patients receiving CT-guided needle biopsy of focal liver lesions were used to generate VMI at energy levels from 40 to 200 keV and VNC images. Images were analyzed objectively regarding contrast-to-noise ratio between lesion center (CNRcent) or periphery (CNRperi) and normal liver parenchyma. Lesion visibility and image quality were evaluated on a 4-point Likert scale by two radiologists. RESULTS: Using VMI/VNC images, readers reported an increased visibility of the lesion compared to the conventional CT images in 18/20 cases. In 75% of cases, the highest visibility was derived by VMI-40. Showing all reconstructions simultaneously, VMI-40 offered the highest visibility in 75% of cases, followed by VNC in 12.5% of cases. Either CNRcent (17/20) or/and CNRperi (17/20) was higher (CNR increase > 50%) in 19/20 cases for VMI-40 or VNC images compared to conventional CT images. VMI-40 showed the highest CNRcent in 14 cases and the highest CNRperi in 12 cases. High image quality was present for all reconstructions with a minimum median of 3.5 for VMI-40 and VMI-50. CONCLUSIONS: When implemented in the CT scanner software, automated contrast enhancement of liver lesions during image-guided biopsy may facilitate the procedure.

DeGIR Quality Report 2019: Report on the treatment quality of minimally invasive methods - Interventional therapy (EVAR) of abdominal aortic aneurysms. / DeGIR-Qualitätsreport 2019: Bericht über die Behandlungsqualität minimalinvasiver Methoden ­ interventionelle Therapie (EVAR) von abdominellen Aortenaneurysmen.

PURPOSE: To analyze the quality of endovascular aortic aneurysm repair using the data of the DeGIR quality management system. Comparison of data between 2011 and 2019. MATERIALS AND METHODS: A retrospective analysis of all data registered in the DeGIR quality management system of the year 2019 was performed regarding the treatment quality for endovascular aortic aneurysm repair. Registration of data was voluntary. As quality parameters indication, treatment process data and quality of results were examined. The latter was judged by treatment success, complication rates and radiation exposure. RESULTS: Out of 189 590 data sets overall 1639 cases of EVAR were registered; compared to 2011 this was an increase of 472 cases. 5.9 % of these cases encompassed emergency treatments. The most frequent indication was an abdominal aneurysm with 72 % of cases. In 54 % of cases, the aortic diameter ranged 50-70 mm. The rates for technical success, over all complications and major complications were 92.8 %, 6.7 % and 6.0 % respectively for all EVAR including emergency indications. In general, EVAR yielded a mortality rate of 1.2 % while emergency procedures had a mortality rate of 7.3 %. Median dose area product and fluoroscopy time were 10 503 cGy × cm2 and 20 minutes respectively at a mean procedure time of 114 minutes. CONCLUSION: Data analysis of the DeGIR quality management system persistently showed a very high technical success rate for endovascular aortic aneurysm repair performed by interventional radiologists accompanied by a low complication rate. KEY POINTS: · The voluntary DeGIR quality assurance-system has reached high acceptance among interventional radiologists.. · The database has nearly 200 000 submissions on record for 2019.. · EVAR by interventional radiologists has shown very high technical success as well as a low complication rate.. CITATION FORMAT: · Frenzel F, Bücker A, Paprottka P et al. DeGIR Quality Report 2019: Report on the treatment quality of minimally invasive methods - Interventional therapy (EVAR) of abdominal aortic aneurysms. Fortschr Röntgenstr 2022; 194: 49 - 61.

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.