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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.)

In the presence of matter, there is no fundamental limit preventing confinement of visible light even down to atomic scales. Achieving such confinement and the corresponding resonant intensity enhancement inevitably requires simultaneous control over atomic-scale details of material structures and over the optical modes that such structures support. By means of self-assembly we have obtained side-by-side aligned gold nanorod dimers with robust atomically defined gaps reaching below 0.5 nm. The existence of atomically confined light fields in these gaps is demonstrated by observing extreme Coulomb splitting of corresponding symmetric and antisymmetric dimer eigenmodes of more than 800 meV in white-light scattering experiments. Our results open new perspectives for atomically resolved spectroscopic imaging, deeply nonlinear optics, ultrasensing, cavity optomechanics, as well as for the realization of novel quantum-optical devices.

We report on three patients with severe gastrointestinal bleeding arising from aortoenteric fistula. Two patients presented with a secondary aortoduodenal fistula. In the first case bleeding occurred 8 months after aortobifemoral graft implantation. In the second patient aortobiliacal graft implantation was performed 22 years before. In the third case the aortoenteric fistula was primary and was caused by an abdominal aortic aneurysm without prior vascular intervention. In the first case diagnosis was made by urgent endoscopy visualizing ongoing bleeding from the duodenal fistula. In the two other patients urgent endoscopy and CT as well could not demonstrate the bleeding source. Aortoenteric fistula was diagnosed endoscopically during severe rebleeding some hours later. Two patients underwent surgery with implantation of an axillobifemoral bypass; the third patient declined further intervention and died. The course shows that aortoduodenal fistula can present with severe but intermittent gastrointestinal bleeding making the diagnosis in the non-bleeding interval difficult. In patients with severe gastrointestinal bleeding and a history of aortic disease (aneurysm, prior aortic graft repair or stenting) an aortoduodenal fistula should be suspected and the indication for surgical intervention should be considered early in spite of negative results of endoscopy and CT.

The diagnostic value of unenhanced helical computed tomography was investigated in a prospective study. In 53 patients (aged 35 to 82 years) with acute flank pain tomography was performed in addition to abdominal plain film and ultrasound examination. All 53 patients had a contraindication for intravenous administration of contrast medium. Ureteral calculi were either confirmed or excluded by retrograde ureteropyelography in 44 cases, in 9 patients by asservation of calculi and clinical follow-up. Helical computed tomography was able to precisely identify all of the 34 ureteral calculi, whereas abdominal plain films led to 6 false positive and 17 false negative findings. In 1 patient with retroperitoneal lymphoma (diagnosed by CT) false positive findings occurred. Unenhanced helical computed tomography reaches a distinctively increased diagnostic value (sensitivity 100%, specificity 95%, accuracy 97%) in the evaluation of acute flank pain as compared to conventional radiologic imaging and ultrasound. This non-invasive procedure is to be considered method of choice for patients with contraindications for the application of radiopaque material.

Objective: The diagnostic value of unenhanced helical computed tomography (CT) for the evaluation of acute flank pain is investigated in a prospective study., Patients and Methods: In 125 patients aged 18-86 years, we performed unenhanced helical CT in addition to abdominal plain film, abdominal ultrasound and urinalysis as a diagnostic measure for acute flank pain. Ureteral calculi were confirmed or, respectively, excluded by retrograde ureteropyelography in 80 cases. In the other cases, diagnosis was verified by clinical course and/or stone asservation., Results: In 91 of 125 patients the flank pain was caused by a ureteral calculus. In 67 of 91 patients with urolithiasis, stones could be collected for analysis. Helical CT was able to precisely identify 90 ureteral calculi. Abdominal plain films led to 8 false-positive and 48 false-negative findings. Thus, sensitivity of plain radiography, ultrasound and urinalysis was 47, 11 and 84% with a specificity 76, 97 and 32%, respectively., Conclusions: Unenhanced helical CT reaches a distinctively increased diagnostic value (sensitivity 99%, specificity 97%) in the evaluation of acute flank pain as compared to plain radiography, ultrasound and urinalysis.

Preoperative embolisation of renal carcinomas has several pros and cons for the patient. The negative aspects can be summarized as 'post-infarction' syndrome'. Radiologically, intrarenal gas formation is always evident. As sterile breakdown products of tumor cell necrosis these have to be interpreted as regular postinterventional findings and not as indicators for infection or even sepsis. Tumor embolisation as a means to reduce surgical difficulties in large hypervascularized renal carcinomas and also as a palliative measure in marked macrohematuria and/or tumor-induced flank pain is thus very conceivable. The best time for the tumor-nephrectomy is the day of embolisation or the first postinterventional day. This makes the nephrectomy easier and prevents the postinfarction syndrome for the patient.