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This document provides concise summaries of several research studies related to medical imaging techniques and their applications in diagnosing and treating various diseases. The studies cover a wide range of topics, including the use of AI algorithms in breast cancer detection, the effectiveness of diffusion tensor imaging in diagnosing brain tumors, and the use of PET imaging in detecting neurodegenerative diseases. The studies offer valuable insights into the potential benefits and limitations of these imaging techniques, but further research and validation are needed to confirm these findings. [Extracted from the article]

Copyright of Die Unfallchirurgie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Tirofiban has been approved for the treatment of acute coronary syndrome. Meanwhile, tirofiban is frequently applied in emergency situations in interventional neuroradiology (INR). The objective of this study was to analyze the risk profile for the off-label use of tirofiban in INR patients. Methods: Data of 86 patients, who underwent neurointerventional therapy and were treated with tirofiban at 2 neuroendovascular centers between January 2016 and July 2017 were retrospectively analyzed. Despite off-label use, recent stroke (< 30 days), recent hemorrhage, thrombocytopenia (< 150,000/µl), activated partial thromboplastin time (aPTT) > 1.3-fold, internation normalised ratio (INR) < 1.5, severe liver insufficiency (Child-Pugh C), and preceding intravenous thrombolysis were considered as contraindications. Results: Median patient age was 62 years (range 26–88 years). Patients received tirofiban for extracranial (n = 35) or intracranial stenting (n = 35), coiling of ruptured cerebral aneurysms (n = 6), continuous intra-arterial nimodipine infusion via microcatheters for subarachnoid hemorrhage (SAH)-related vasospasm (n = 5), or thrombotic complications during neuroendovascular procedures (n = 5). The desired effect of preventing thrombotic complications when applying tirofiban off-label was achieved in 81 of 86 patients (94.2%). Relevant tirofiban-associated complications occurred in 14 patients (16.3%), of which 9 patients received i.v. thrombolysis for treatment of acute ischemic stroke shortly before starting therapy with tirofiban. Of the 86 patients 12 died, while the overall tirofiban-related mortality was 2.3% (2 patients died due to ICH). Logistic regression analysis revealed age to be the only parameter significantly associated with development of tirofiban-associated complications (p = 0.026). Conclusion: Whereas the safety profile of tirofiban when applied off-label in INR is acceptable, the highest risk for relevant tirofiban-associated complications is observed in older patients treated by emergency stenting for acute stroke. [ABSTRACT FROM AUTHOR]

Objectives: Photon-counting computed tomography has lately found its way into clinical routine. The new technique could offer substantial improvements regarding general image quality, image noise, and radiation dose reduction. This study evaluated the first abdominal examinations in clinical routine and compared the results to conventional computed tomography. Methods: In this single-center retrospective study, 66 patients underwent photon-counting and conventional abdominal CT. Four radiologists assessed general image quality, image noise, and image artifacts. Signal-to-noise ratio and dose properties of both techniques within the clinical application were compared. An ex vivo phantom study revealed the radiobiological impact by means of DNA double-strand break foci in peripheral blood cells by enumerating γ-H2AX+53BP1 foci. Results: General image quality in accordance with the Likert scale was found superior for photon-counting CT (4.74 ± 0.46 vs. 4.25 ± 0.54; p < 0.001). Signal-to-noise ratio (p < 0.001) and also dose exposure were higher for photon-counting CT (DLP: 419.2 ± 162.2 vs. 372.3 ± 236.6 mGy*cm; p = 0.0435). CT exposure resulted in significantly increased DNA damage in comparison to sham control (p < 0.001). Investigation of the average foci per cell and radiation-induced foci numbers revealed significantly elevated numbers (p = 0.004 and p < 0.0001, respectively) after photon-counting CT. Conclusion: Photon-counting CT in abdominal examinations showed superior results regarding general image quality and signal-to-noise ratio in clinical routine. However, this seems to be traded for a significantly higher dose exposure and corresponding double-strand break frequency. Optimization of standard protocols in further clinical applications is required to find a compromise regarding picture quality and dose exposure. Key Points: • Photon-counting computed tomography promises to enhance the diagnostic potential of medical imaging in clinical routine. • Retrospective single-center study showed superior general image quality accompanied by higher dose exposure in initial abdominal PCCT protocols compared to state-of-the-art conventional CT. • A simultaneous ex vivo phantom study revealed correspondingly increased frequencies of DNA double-strand breaks after PCCT. [ABSTRACT FROM AUTHOR]

Copyright of Herz is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: Cochlea implant surgery with proper positioning of the cochlear electrode can be challenging. Intraoperative real-time hybrid laser-fluoroscopic-guided navigation based on a multiplanar cone beam computed tomography (CBCT) dataset opens up the opportunity to immediate radiological control of primary electrode misalignments and offering new insights into the cochlea electrode insertion routes and favorable cochlear implant-insertion angle. Methods: In this retrospective study, 50 cases (29 males, 18 females) of conventional electrode implantation (without intraoperative image control; group A) and nine cases (7 males, 2 females) of CBCT-laser-fluoroscopic-guided surgery (group B) were included in the present study. CBCT-laser-guided surgery under real-time fluoroscopic control was conducted using an intraoperative C-arm CBCT. All patients received preoperative cross-sectional imaging (CT and MRI), in which cochlear malformation could be excluded. Postoperatively, we looked for electrode misplacements. Results: In group A, electrode misalignment was detected postoperatively in 14 of 50 cases (28.0%). In group B, primary electrode misalignment was detected intraoperatively in two patients (22.2%). In both patients, the misalignments were corrected in the same session. The comparison of cochlear insertion angles showed significant differences. Group A: 47.5 ± 2.6° (actual conventional surgery) vs 17.6 ± 2.8° (theoretical CBCT-laser-fluoroscopic-guided surgery) P < 0.001. Group A vs group B: 47.5 ± 2.6° (actual conventional surgery; Group A) vs 17.9 ± 2.5° (actual CBCT-laser-fluoroscopic-guided surgery; Group B) P < 0.001. Conclusion: We consider that an intraoperative hybrid CBCT-laser-fluoroscopic-controlled approach in cochlear implant surgery using a C-arm CT can be beneficial, because electrode misalignments can be reduced and if it does occur, remedied in the same surgical session. [ABSTRACT FROM AUTHOR]

Dual-energy CT provides enhanced diagnostic power with similar or even reduced radiation dose as compared to single-energy CT. Its principle is based on the distinct physical properties of low and high energetic photons, which, however, may also affect the biological effectiveness and hence the extent of CT-induced cellular damage. Therefore, a comparative analysis of biological effectiveness of dual- and single-energy CT scans with focus on early gene regulation and frequency of radiation-induced DNA double strand breaks (DSBs) was performed. Blood samples from three healthy individuals were irradiated ex vivo with single-energy (80 kV and 150 kV) and dual-energy tube voltages (80 kV/Sn150kV) employing a modern dual source CT scanner resulting in Volume Computed Tomography Dose Index (CTDIvol) of 15.79–18.26 mGy and dose length product (DLP) of 606.7–613.8 mGy*cm. Non-irradiated samples served as a control. Differential gene expression in peripheral blood mononuclear cells was analyzed 6 h after irradiation using whole transcriptome sequencing. DSB frequency was studied by 53BP1 + γH2AX co-immunostaining and microscopic evaluation of their focal accumulation at DSBs. Neither the analysis of gene expression nor DSB frequency provided any evidence for significantly increased biological effectiveness of dual-energy CT in comparison to samples irradiated with particular single-energy CT spectra. Relative to control, irradiated samples were characterized by a significantly higher rate of DSBs (p < 0.001) and the shared upregulation of five genes, AEN, BAX, DDB2, FDXR and EDA2R, which have already been suggested as radiation-induced biomarkers in previous studies. Despite steadily decreasing doses, CT diagnostics remain a genotoxic stressor with impact on gene regulation and DNA integrity. However, no evidence was found that varying X-ray spectra of CT impact the extent of cellular damage. [ABSTRACT FROM AUTHOR]

Purpose: Uric acid (UA) calculi can be referred to chemolitholysis rather than invasive treatment. Dual-energy computed tomography (DECT) may be able to distinguish between UA and non-UA (NUA) calculi. The aim of this study was to evaluate the validity of third-generation DECT for the first time and to investigate whether combining DECT with clinical parameters can increase its predictive accuracy. Materials and methods: All patients who presented to our emergency department between January 2015 and March 2017 with urinary stones were prospectively included in this observational study and underwent DECT with subsequent interventional stone removal. Stone composition was analyzed using infrared spectrometry as the gold standard. Predictive accuracy of DECT and clinical covariates was computed by assessing univariate and multivariate areas under the curve (AUCs). Results: Of 84 patients with 144 urinary stones, 10 (11.9%) patients had UA stones according to infrared spectrometry, and the remaining stones were NUA or mixed stones. DECT had a positive predictive value of 100% and a negative predictive value of 98.5% for UA stones. The AUC for urine pH alone was 0.71 and 0.97 for DECT plus urine pH. No UA stones were found in patients with a urine pH above > 5.5. Mean DLP was 225.15 ± 128.60 mGy*cm and mean effective dose was 3.38 ± 1.93 mSv. Conclusions: DECT is a safe method for assigning patients to oral chemolitholysis. Clinical preselection of patients based on urinary pH (< 6.0) leads to a more liable use of DECT. Third-generation DECT needs significant lower radiation doses compared to previous generations. [ABSTRACT FROM AUTHOR]