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Purpose: To assess accuracy, the frequency of hemorrhagic complications and computed tomography (CT) radiation dose parameters in pediatric patients undergoing landmark-guided external ventricular drain (EVD) placement in an emergency setting. Methods: Retrospective analysis comprised 36 EVD placements with subsequent CT control scans in 29 patients (aged 0 to 17 years) in our university hospital from 2008 to 2022. The position of the EVD as well as the presence and extension of bleeding were classified according to previously established grading schemes. Dose length product (DLP), volume-weighted CT dose index (CTDIvol) and scan length were extracted from the radiation dose reports and compared to the diagnostic reference values (DRLs) issued by the German Federal Office for Radiation Protection. Results: After the initial EVD placement, optimal positioning of the catheter tip into the ipsilateral frontal horn or third ventricle (Grade I), or a functional positioning in the contralateral lateral ventricle or the non-eloquent cortex (Grade II), was achieved in 28 and 8 cases, respectively. In 32 of 36 procedures, no evidence of hemorrhage was present in the control CT scan. Grade 1 (<1 mL) and Grade 2 (≥1 to 15 mL) bleedings were detected after 3 and 1 placement(s), respectively. For control scans after EVD placements, CTDIvol (median [25%; 75% quartile]) was 39.92 [30.80; 45.55] mGy, DLP yielded 475.50 [375.00; 624.75] mGy*cm and the scan length result was 136 [120; 166] mm. Exceedances of the DRL values were observed in 14.5% for CTDIvol, 12.7% for DLP and 65.6% for the scan length. None of these values was in the range requiring a report to the national authorities. Conclusion: Landmark-based emergency EVD placement in pediatric patients yielded an optimal position in most cases already after the initial insertion. Complications in terms of secondary hemorrhages are rare. CT dose levels associated with the intervention are below the reportable threshold of the national DRLs in Germany. [ABSTRACT FROM AUTHOR]

Introduction: Despite the development of non‐fluoroscopic catheter visualization options, fluoroscopy is still used in most ablation procedures. The aim of this multicenter study was to evaluate the safety and efficacy of a new ultra‐low dose radiation protocol for EP procedures in a large number of patients. Methods and results: A total of 3462 consecutive patients (male 1926 (55.6%), age 64.4 ± 14.0 years, BMI 26.65 ± 4.70) undergoing radiofrequency ablation (left atrial (n = 2316 [66.9%], right atrial (n = 675 [19.5%], or ventricular (n = 471 [13.6%]) in three German centers were included in the analysis. Procedures were performed using a new ultra‐low dose protocol operating at 8nGy for fluoroscopy and 36nGy for cine‐loops. Additionally a very low framerate (2‐3FPS) was used. Using the new protocol very low Air kerma‐area product (KAP) values were achieved for left atrial ablations (104.25 ± 84.22 μGym2), right atrial ablations (70.98 ± 94.79 μGym2) and ablations for ventricular tachycardias or PVCs (78.62 ± 66.59 μGym2). Acute procedural success was achieved in 3289/3388 (97.1%) while the rate of major complications was very low compared to previously published studies not using low dose settings (n = 20, 0.6%). Conclusion: The ultra‐low dose, low framerate protocol leads to very low radiation doses for all EP procedures while neither procedural time, fluoroscopy time nor success or complication rates were compromised. When compared to current real‐world Air KAP data the new ultra‐low dose fluoroscopy protocol reduces radiation exposure by more than 90%. [ABSTRACT FROM AUTHOR]

Introduction: The present study investigates the influence of joint prostheses on the amount of scattered radiation in a simulated angiography set-up.Materials and Methods: A clinical angiography system (Artis Zee, Siemens Healthineers, Germany) with a water phantom as a scattering object was used. The scattered radiation of the water phantom was repeatedly measured without prosthesis, with a knee prosthesis and a hip prosthesis made from titanium, aluminum, vanadium, ceramics and polyethylene. For radiation measurement an ionization chamber (ambient dose equivalent rate from 0.1 µSv/h - 100 Sv/h, UMo, Berthold Technologies, Germany) was used. It was positioned on the right side of the phantom simulating an interventional procedure via the right femoral artery. The ionization chamber was positioned at 5 different heights (30, 100, 130, 150 and 165 cm), simulating different body parts of the interventionist. In addition, the amount of scattered radiation in relation to the tube angulation was investigated.Results: Averaged over all angulations at a height of 165 cm, the radiation dose was 2.7 times higher (1935 µSv/h, p < 0.01) when a hip prosthesis was present in comparison to no prosthesis (713 µSv/h). The radiation dose was 3.9 times higher with the integration of a knee prosthesis (2778 µSv/h, p < 0.01) compared to that without prosthesis. The average radiation dose over all angulations and all heights was 1491 µSv/h without prosthesis, 4538 µSv/h with a hip prothesis and 5023 µSv/h with a knee prosthesis respectively.Conclusion: This experimental study shows a significant increase in the radiation dose when a joint prosthesis is present in the examination field. Special attention and sufficient radiation protection is therefore necessary for investigations with implanted prostheses. [ABSTRACT FROM AUTHOR]