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Competing Interests: The authors declare that they have no conflict of interest.

Objective: The aim of this study was to evaluate whether a 3-dimensional (3D) camera can outperform highly trained technicians in precision of patient positioning and whether this transforms into a reduction in patient exposure., Materials and Methods: In a single-center study, 3118 patients underwent computer tomography (CT) scans of the chest and/or abdomen on a latest generation single-source CT scanner supported with an automated patient positioning system by 3D camera. One thousand five hundred fifty-seven patients were positioned laser-guided by a highly trained radiographer (camera off) and 1561 patients with 3D camera (camera on) guidance. Radiation parameters such as effective dose, organ doses, CT dose index, and dose length product were analyzed and compared. Isocenter accuracy and table height were evaluated between the 2 groups., Results: Isocenter positioning was significantly improved with the 3D camera ( P < 0.001) as compared with visual laser-guided positioning. Absolute table height differed significantly ( P < 0.001), being higher with camera positioning (165.6 ± 16.2 mm) as compared with laser-guided positioning (170.0 ± 20.4 mm). Radiation exposure decreased using the 3D camera as indicated by dose length product (321.1 ± 266.6 mGy·cm; camera off: 342.0 ± 280.7 mGy·cm; P = 0.033), effective dose (3.3 ± 2.7 mSv; camera off: 3.5 ± 2.9; P = 0.053), and CT dose index (6.4 ± 4.3 mGy; camera off: 6.8 ± 4.6 mGy; P = 0.011). Exposure of radiation-sensitive organs such as colon ( P = 0.015) and red bone marrow ( P = 0.049) were also lower using the camera., Conclusions: The introduction of a 3D camera improves patient positioning in the isocenter of the scanner, which results in a lower and also better balanced dose reduction for the patients., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The diagnosis of (significant) prostate cancer ((s)PC) is impeded by overdiagnosis and unnecessary biopsy. Risk calculators (RC) have been developed to mitigate these issues. Contemporary RCs integrate clinical characteristics with mpMRI findings., Objective: To validate two of these models-the MRI-ERSPC-RC-3/4 and the risk model of van Leeuwen., Methods: 265 men with clinical suspicion of PC were enrolled. Every patient received a prebiopsy mpMRI, which was reported according to PI-RADS v2.1, followed by MRI/TRUS fusion-biopsy. Cancers with ISUP grade ≥ 2 were classified as sPC., Outcome Measurements and Statistical Analysis: Statistical analysis was performed by comparing discrimination, calibration, and clinical utility RESULTS: There was no significant difference in discrimination between the RCs. The MRI-ERSPC-RC-3/4-RC showed a nearly ideal calibration-slope (0.94; 95% CI 0.68-1.20) than the van Leeuwen model (0.70; 95% CI 0.52-0.88). Within a threshold range up to 9% for a sPC, the MRI-ERSPC-RC-3/4-RC shows a greater net benefit than the van Leeuwen model. From 10 to 15%, the van Leeuwen model showed a higher net benefit compared to the MRI-ERSP-3/4-RC. For a risk threshold of 15%, the van Leeuwen model would avoid 24% vs. 14% compared to the MRI-ERSPC-RC-3/4 model; 6% vs. 5% sPC would be overlooked, respectively., Conclusion: Both risk models supply accurate results and reduce the number of biopsies and basically no sPC were overlooked. The van Leeuwen model suggests a better balance between unnecessary biopsies and overlooked sPC at thresholds range of 10-15%. The MRI-ERSPC-RC-3/4 risk model provides better overall calibration., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Purpose: Controversy exists on the association of arterial hypertension (HTN) and neurovascular compression (NVC) at the ventrolateral medulla (VLM). No standardized and reproducible technique has been introduced yet for detection of NVC in HTN. This study aimed to generate, analyze and compare different results of exact reproducible anatomical 3D-representations of the VLM in patients with HTN, based on magnetic resonance imaging (MRI)., Methods: A 3T scanner provided MRI (T2-constructive interference in steady state (CISS) high resolution imaging and three-dimensional Time-of-flight (3D-TOF) angiography) from the posterior fossa of 44 patients with clinical treatment-resistant HTN. Image processing consists of segmentation of the CISS data, registration and fusion of the CISS and TOF data and visualization. For each patient two 3D-visualizations (before and after fusion) were obtained. The reproduction quality of the vessels, flow-related signal variability and pulsation artifacts were analyzed and compared, using a ranking score., Results: Integrating vascular information from TOF into CISS data reduced artifacts in 3D-visualizations of exclusively processed CISS data. The quality of 3D-visualization of the vessels near the brain stem was significantly improved (p = 0.004). The results were reproducible and reliable. The quality of the 3D-presentations of neurovascular relationships at the VLM improved significantly (p < 0.001)., Conclusion: The 3D-visualization of fused image data provides an excellent overview of the relationship between cranial nerves and vessels at the VLM and simplifies the detection of NVC in HTN. It provides a powerful tool for future clinical and scientific research. Although microvascular decompression (MVD) in treatment resistant HTN is not a standard procedure, it can be discussed in selected patients with intractable severe HTN.

Purpose:  To determine the predictive value of 3-dimensional spoiled gradient-echo volumetric interpolated breath-hold examination (VIBE) using subtraction to evaluate the short-term effect of therapy for facial palsy., Materials and Methods:  We included 97 patients with idiopathic facial palsy (52 male, 45 female; aged 50.7 ± 19.4 years) who underwent MR imaging with a contrast agent after starting therapy. The mean interval between onset and therapy was 1.55 ± 1.69 days, between therapy and MR imaging was 3.19 ± 2.78 days, and between MR imaging and assessment of the therapeutic effect was 3.50 ± 0.71 days. The degree of therapeutic effect was determined using a 4-grade scale based on the House-Brackmann scale for grading facial nerve function. Two radiologists reviewed VIBE with pre- and postcontrast subtraction using the 4-point scale. We evaluated the diagnostic performance and compared the degree of therapeutic effect and enhancement of facial nerves that were divided into 5 segments bilaterally., Results:  We identified 98 facial palsy initially and significant enhancement in 55 facial nerves after the start of therapy and residual palsy in 87. Sensitivity for all facial palsy was 62.0 %, specificity was 90.9 %, positive predictive value was 98.2 %, negative predictive value was 23.3 %, and accuracy was 65.3 %. Eleven patients recovered completely, 1 showed significant enhancement, and the remaining 10 did not show significant enhancement of the facial nerve., Conclusion:  VIBE has a potential to predict the prognostic outcome and assess facial palsy after the start of therapy., Key Points:   · Three-dimensional spoiled gradient-echo volumetric interpolated breath-hold examination (VIBE) using subtraction can be useful to predict residual facial palsy after initial therapy.. · Strong enhancement of the facial nerve on VIBE using subtraction was associated with residual facial palsy after the start of therapy.. · Patients with a favorable prognosis did not show strong enhancement.., Citation Format: · Tomita H, Detmar K, Nakajima Y et al. Predictive Value of VIBE using Subtraction to Evaluate Idiopathic Facial Palsy after Starting Therapy. Fortschr Röntgenstr 2020; 192: 1183 - 1189., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Artificial intelligence (AI) algorithms are increasingly used in radiology. The main areas of application are, for example, the detection of lung lesions and the diagnosis of chronic obstructive and interstitial lung diseases. The aim of our study was to train and evaluate a package of algorithms that analyze data from computed tomographic (CT) images of the chest and provide quantitative measurements to the radiologist. The following algorithms were trained: lung lesion detection and measurement, lung lobe segmentation, vessel segmentation and measurement, coronary calcium scoring, measurement and density analysis of vertebral bodies. AI-supported algorithms will become part of daily routine of the radiologist in the future. Tasks that do not require medical expertise can be performed by AI. However, our results show that, based on the current accuracy, verification by an experienced radiologist is necessary.

Aim: To investigate the influence of scan time point and volume of intravenous contrast material in 18F-FDG PET/CT on maximum and mean standardized uptake values (SUV max / mean ) in bloodpool and liver., Methods: In 120 patients scheduled for routine whole-body 18F-FDG PET/CT the maximum and mean standardized uptake values (SUV max /SUV mean ) in the liver and blood pool were measured after varying scan time-point (delay 0 s-140 s post injectionem) and volume of contrast material (CM; 0 ml, 80 ml, 100 ml of 300 mg/ml of Iodine). Six groups of 20 patients were investigated: (1) without intravenous CM, (2-5) injection of 100 ml CM with a delay of 80 s (2), 100 s (3), 120 s (4), 140 s (5), and 80 ml CM and a delay of 100 s (6). SUV max , SUV mean , maximum Hounsfield units (HU max ) and average Hounsfield units (HU av ) were calculated with the use of manually drawn regions of interests (ROIs) over the aortic arch and healthy liver tissue., Results: SUV max in bloodpool was significantly higher in group 3, 4 and 6 compared to group 1. Groups 2 and 5 also showed higher mean values of SUV max , but the difference was not significant. SUV mean in bloodpool was also higher in groups 2, 3, 4, 5 and 6 compared to group 1, but the differences were only statistically significant in group 3. Both SUV max and SUV mean in healthy liver tissue did not show significant differences when compared to the non contrast-enhanced control group., Conclusion: SUV max and to a lesser extent SUV mean measured in CM enhanced FDG PET/CT in blood pool could be significantly altered in high contrast CT examinations. This should be kept in mind in PET/CT protocols and evaluation relying on SUV max and SUV mean , for example when used in the assessment of therapy response, especially in highly vascularized tumor lesions. ZIEL:: Das Ziel dieser Studie war den Einfluss von unterschiedlichen Messzeitpunkten und Volumina bei der Gabe von intravenösem Kontrastmittel in der 18F-FDG PET/CT auf SUV max und SUV mean im Blutpool und Lebergewebe zu untersuchen., Methoden: In 120 Patienten, geplant für eine Ganzkörper 18F-FDG -PET/CT, wurden die maximalen und durchschnittlichen standardisierten Aufnahmewerte (SUV max /SUV mean ) in der Leber und im Blutpool, jeweils nach unterschiedlichen Messzeitpunkten (Verzögerung 0 s-140 s post injectionem) und verschiedenen Volumina von Kontrastmittel (KM; 0 ml, 80 ml, 100 ml mit einer Konzentration von 300 mg/ml Jod) gemessen. Sechs Gruppen von je 20 Patienten wurden untersucht: (1) ohne intravenöses KM, (2-5) Injektion von 100 ml KM mit einer Verzögerung von 80 s (2), 100 s (3), 120 s (4), 140 s (5), und 80 ml KM mit einer Verzögerung von 100 s (6). Es wurden jeweils die SUV max , SUV mean , die maximalen and die durchschnittlichen Hounsfield Einheiten (HU av , HU max ) anhand manuell gezeichneter Bereiche von Interesse (ROIs) im Aortenbogen und im gesunden Lebergewebe berechnet., Ergebnisse: Die SUV max im Blutpool waren im Vergleich zur Gruppe 1 signifikant höher in Gruppe 3, 4 und 6. Die Gruppen 2 und 5 zeigten ebenfalls höhere Durchschnittswerte von SUV max , der Unterschied war jedoch nicht signifikant. Die SUV mean im Blutpool waren im Vergleich zur Gruppe 1 ebenfalls höher in den Gruppen 2, 3, 4, 5 und 6, allerdings waren die Unterschiede nur in Gruppe 3 statistisch signifikant. Im Lebergewebe zeigten sowohl SUV max , als auch SUV mean keine signifikanten Unterschiede im Vergleich zu der nativen Kontrollgruppe., Schlussfolgerungen: In der Kontrastmittel-gestützten FDG PET/CT können die SUV max und in geringerem Ausmaß auch SUV mean im Blutpool durch Hochkontrast-CT Untersuchungen signifikant beeinflusst werden. Dies sollte bei PET/CT Protokollen bzw. Auswertungen, die auf SUV max und SUV mean beruhen, berücksichtigt werden, zum Beispiel bei der Beurteilung des Therapieansprechens insbesondere bei stark vaskularisiertem Tumorgewebe., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (Schattauer GmbH.)