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The introduction of photon-counting detector CT (PCD-CT) marks a remarkable leap in innovation in CT imaging. The new detector technology allows X-rays to be converted directly into an electrical signal without an intermediate step via a scintillation layer and allows the energy of individual photons to be measured. Initial data show high spatial resolution, complete elimination of electronic noise, and steady availability of spectral image data sets. In particular, the new technology shows promise with respect to the imaging of osseous structures. Recently, PCD-CT was implemented in the clinical routine. The aim of this review was to summarize recent studies and to show our first experiences with photon-counting detector technology in the field of musculoskeletal radiology.We performed a literature search using Medline and included a total of 90 articles and reviews that covered recent experimental and clinical experiences with the new technology.In this review, we focus on (1) spatial resolution and delineation of fine anatomic structures, (2) reduction of radiation dose, (3) electronic noise, (4) techniques for metal artifact reduction, and (5) possibilities of spectral imaging. This article provides insight into our first experiences with photon-counting detector technology and shows results and images from experimental and clinical studies. · This review summarizes recent experimental and clinical studies in the field of photon-counting detector CT and musculoskeletal radiology.. · The potential of photon-counting detector technology in the field of musculoskeletal radiology includes improved spatial resolution, reduction in radiation dose, metal artifact reduction, and spectral imaging.. · PCD-CT enables imaging at lower radiation doses while maintaining or even enhancing spatial resolution, crucial for reducing patient exposure, especially in repeated or prolonged imaging scenarios.. · It offers promising results in reducing metal artifacts commonly encountered in orthopedic or dental implants, enhancing the interpretability of adjacent structures in postoperative and follow-up imaging.. · With its ability to routinely acquire spectral data, PCD-CT scans allow for material classification, such as detecting urate crystals in suspected gout or visualizing bone marrow edema, potentially reducing reliance on MRI in certain cases.. Bette S, Risch F, Becker J et al. Photon-counting detector CT - first experiences in the field of musculoskeletal radiology. Fortschr Röntgenstr 2024; DOI 10.1055/a-2312-6914., Competing Interests: The Department of Radiology received research funding from Siemens Healthineers for research in the field of photon-counting CT., (Thieme. All rights reserved.)

Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht.

Purpose:  To evaluate imaging patterns of a COVID-19 infection of the lungs on chest radiographs and their value in discriminating this infection from other viral pneumonias., Materials and Methods:  All 321 patients who presented with respiratory impairment suspicious for COVID-19 infection between February 3 and May 8, 2020 and who received a chest radiograph were included in this analysis. Imaging findings were classified as typical for COVID-19 (bilateral, peripheral opacifications/consolidations), non-typical (findings consistent with lobar pneumonia), indeterminate (all other distribution patterns of opacifications/consolidations), or none (no opacifications/consolidations). The sensitivity, specificity, as well as positive and negative predictive value for the diagnostic value of the category "typical" were determined. Chi² test was used to compare the pattern distribution between the different types of pneumonia., Results:  Imaging patterns defined as typical for COVID-19 infections were documented in 35/111 (31.5 %) patients with confirmed COVID-19 infection but only in 4/210 (2 %) patients with any other kind of pneumonia, resulting in a sensitivity of 31.5 %, a specificity of 98.1 %, and a positive and negative predictive value of 89.7 % or 73 %, respectively. The sensitivity could be increased to 45.9 % when defining also unilateral, peripheral opacifications/consolidations with no relevant pathology contralaterally as consistent with a COVID-19 infection, while the specificity decreases slightly to 93.3 %. The pattern distribution between COVID-19 patients and those with other types of pneumonia differed significantly (p < 0.0001)., Conclusion:  Although the moderate sensitivity does not allow the meaningful use of chest radiographs as part of primary screening, the specific pattern of findings in a relevant proportion of those affected should be communicated quickly as additional information and trigger appropriate protective measures., Key Points:   · COVID-19 infections show specific X-ray image patterns in 1/3 of patients.. · Bilateral, peripheral opacities and/or consolidations are typical imaging patterns.. · Unilateral, peripheral opacities and/or consolidations should also raise suspicion of COVID-19 infection.., Citation Format: · Kasper J, Decker J, Wiesenreiter K et al. Typical Imaging Patterns in COVID-19 Infections of the Lung on Plain Chest Radiographs to Aid Early Triage. Fortschr Röntgenstr 2021; 193: 1189 - 1196., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

Competing Interests: Die Autorinnen/Autoren geben an, dass kein Interessenkonflikt besteht.

Competing Interests: Die Autoren geben an, dass kein Interessenkonflikt besteht.

Purpose  To evaluate the results of interventional endovascular therapy of incidental and symptomatic visceral artery aneurysms in the elective and emergency situation. Materials and Methods  43 aneurysms in 38 patients (19 female, 19 male, mean age: 57 ± 16 years [18 - 82]) were treated between 2011 and 2015. The characteristics of the aneurysms (true vs. false aneurysm, size, etiology, location, symptoms) were considered. Furthermore, we evaluated the intervention with respect to technical success, embolic/occlusive agents used, therapy-associated complications and post-interventional follow-up.  Results  23 true aneurysms (maximum diameter: 22 ± 18 mm [11 - 67 mm]) and 20 false aneurysms (maximum diameter: 9 ± 33 mm [3 - 150 mm]) were evaluated. The splenic (n = 14) and renal arteries (n = 18) were most frequently affected. The etiology was most commonly degenerative-atherosclerotic (47 %) or iatrogenic post-operative (19 %). 18/48 interventions were performed due to active bleeding. False aneurysms were associated significantly more often with active bleeding (63 vs. 25 %, p = 0.012). 41/48 treatments were technically successful. Re-intervention was necessary 6 times. In 2 cases the endovascular approach did not succeed. There was a complication rate of 10 %, whereby only 4 minor and 1 major complications occurred. No patient suffered from permanent sequelae. Aneurysms were primarily treated by using coils and if necessary additional embolic agents (liquid embolic agent or vascular plugs) (75 %). In the follow-up period, reperfusion of treated aneurysms occurred at a rate of 7 % (n = 3). Conclusion  Interventional endovascular therapy of visceral artery aneurysms is safe and effective in the elective treatment of incidental aneurysms as well as in significantly more frequent hemorrhaging false aneurysms in the emergency situation. Key points   · Interventional endovascular therapy of visceral artery aneurysms is safe and effective.. · In more than 60 % of cases visceral artery pseudoaneurysms are associated significantly more often with a history of bleeding or acute bleeding. Hence, there is a need for (interventional) therapy even in small pseudoaneurysms.. · Follow-up seems to be useful to detect reperfusion as manifestation of treatment failure.. Citation Format · Ruhnke H, Kröncke TJ, . Visceral Artery Aneurysms and Pseudoaneurysms: Retrospective Analysis of Interventional Endovascular Therapy of 43 Aneurysms. Fortschr Röntgenstr 2017; 189: 632 - 639., Competing Interests: Disclosure The authors report no conflicts of interest in this work., (© Georg Thieme Verlag KG Stuttgart · New York.)

Immediately after emergency caesarean section a 37 yr old patient suffered severe atonic bleeding requiring different operating procedures (Clipping of the uterine arteries) in combination with an uterotonic and haemostaseological medication as well as massive transfusion of blood components and recombinant factor VIIa. After a period of 17 days without any bleeding the patient presented to the emergency room with recurrent massive uterine bleeding. Transarterial embolization of the anterior bundles of the iliac arteries in combination with a second uterotonic and haemostaseological medication stopped the haemorrhage. Reasons and risk factors of a recurrent postpartum bleeding are discussed and a multidisciplinary algorithm for treatment is proposed., (© Georg Thieme Verlag Stuttgart · New York.)