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1.
Johannes Boos Patric Kröpil Dirk Klee Philipp Heusch Lars Schimmöller Jörg Schaper Gerald Antoch Rotem S. Lanzman 《Pediatric radiology》2014,44(9):1065-1069
Background
Organ-specific dose reduction significantly reduces the radiation exposure of radiosensitive organs.Objective
The purpose of this study was to assess the impact of a novel organ-specific dose reduction algorithm on image quality of pediatric chest CT.Materials and methods
We included 28 children (mean age 10.9?±?4.8 years, range 3–18 years) who had contrast-enhanced chest CT on a 128-row scanner. CT was performed at 100 kV using automated tube current modulation and a novel organ-specific dose-reduction algorithm (XCare?; Siemens, Forchheim, Germany). Seven children had a previous chest CT performed on a 64-row scanner at 100 kV without organ-specific dose reduction. Subjective image quality was assessed using a five-point scale (1-not diagnostic; 5-excellent). Contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were assessed in the descending aorta.Results
Overall mean subjective image quality was 4.1?±?0.6. In the subgroup of the seven children examined both with and without organ-specific dose reduction, subjective image quality was comparable (score 4.4?±?0.5 with organ-specific dose reduction vs. 4.4?±?0.7 without it; P?>?0.05). There was no significant difference in mean signal-to-noise ratio and contrast-to-noise ratio with organ-specific dose reduction (38.3?±?10.1 and 28.5?±?8.7, respectively) and without the reduction (35.5?±?8.5 and 26.5?±?7.8, respectively) (P?>?0.05). Volume computed tomography dose index (CTDIvol) and size-specific dose estimates did not differ significantly between acquisitions with the organ-specific dose reduction (1.7?±?0.8 mGy) and without the reduction (1.7?±?0.8 mGy) (P?>?0.05).Conclusion
Organ-specific dose reduction does not have an impact on image quality of pediatric chest CT and can therefore be used in clinical practice to reduce radiation dose of radiosensitive organs such as breast and thyroid gland. 相似文献2.
Miese F Kröpil P Ostendorf B Scherer A Buchbender C Quentin M Lanzman RS Blondin D Schneider M Bittersohl B Zilkens C Jellus V Ch Mamisch T Wittsack HJ 《European journal of radiology》2011,80(3):e427-e431
Purpose
To assess motion artifacts in dGEMRIC of finger joints and to evaluate the effectiveness of motion correction.Materials and methods
In 40 subjects (26 patients with finger arthritis and 14 healthy volunteers) dGEMRIC of metacarpophalangeal joint II was performed. Imaging used a dual flip angle approach (TE 3.72 ms, TR 15 ms, flip angles 5° and 26°). Two sets of T1 maps were calculated for dGEMRIC analysis from the imaging data for each subject: one with and one without motion correction. To compare image quality, visual grading analysis and precision of dGEMRIC measurement of both dGEMRIC maps for each case were evaluated.Results
Motion artifacts were present in 82% (33/40) of uncorrected dGEMRIC maps. Motion artifacts were graded as severe or as rendering evaluation impossible in 43% (17/40) of uncorrected dGEMRIC maps. Motion corrected maps showed significantly less motion artifacts (P < 0.001) and were graded as evaluable in 97% (39/40) of cases. Precision was significantly higher in motion corrected images (coefficient of variation (CV = .176 ± .077), compared to uncorrected images (CV .445 ± .347) (P < .001). Motion corrected dGERMIC was different in volunteers and patients (P = .044), whereas uncorrected dGEMRIC was not (P = .234).Conclusion
Motion correction improves image quality, dGEMRIC measurement precision and diagnostic performance in dGEMRIC of finger joints. 相似文献3.
Rotem S. Lanzman Joachim Winter Dirk Blondin Günter Fürst Axel Scherer Falk R Miese Suhny Abbara Patric Kr?pil 《Korean journal of radiology》2011,12(5):611-619
Pacemakers and implantable cardioverter defibrillators (ICDs) are being increasingly employed in patients suffering from cardiac rhythm disturbances. The principal objective of this article is to familiarize radiologists with pacemakers and ICDs on chest radiographs and CT scans. Therefore, the preferred lead positions according to pacemaker types and anatomic variants are introduced in this study. Additionally, the imaging features of incorrect lead positions and defects, as well as complications subsequent to pacemaker implantation are demonstrated herein. 相似文献
4.
Quentin M Kröpil P Steiner S Lanzman RS Blondin D Miese F Choy G Abbara S Scherer A 《Der Radiologe》2011,51(1):59-64
Background
The purpose of this study was to evaluate the prevalence and clinical significance of incidental cardiac findings in non-ECG-gated chest CT.Patients and methods
Non-ECG-gated chest CT examinations of 300 patients were retrospectively analyzed for incidental cardiac findings. Subsequently, these findings were evaluated for their clinical relevance by a cardiologist.Results
A total of 107 out of 300 examined patients had 174 incidental cardiac findings including coronary calcification (90), aortic/mitral valve calcification (42), iatrogenic changes (23), pericardial effusion (6), dilatation of the heart (4), myocardial changes (3), thrombus in the left ventricle (2), constrictive pericarditis (2) and atrial myxoma (1). Of the cardiac findings 51% were described in the written report and in 53 out of the 107 patients the cardiac findings were unknown. Newly detected incidental findings from 8 patients were rated as clinically significant: pericardial effusion (4), constrictive pericarditis (1), thrombus in the left ventricle (1), atrial myxoma (1) and dilatation of the heart (1).Conclusion
Incidental cardiac findings are frequent in non-ECG-gated chest CT and may have a high clinical relevance. 相似文献5.
A. Scherer Dr. P. Kr?pil P. Heusch C. Buchbender P. Sewerin D. Blondin R.S. Lanzman F. Miese B. Ostendorf E. B?lke U. M?dder G. Antoch 《Der Radiologe》2011,51(11):969-978
Purpose
Medical curricula are currently being reformed in order to establish superordinated learning objectives, including, e.g. diagnostic, therapeutic and preventive competences. This requires a shifting from traditional teaching methods towards interactive and case-based teaching concepts. Conceptions, initial experiences and student evaluations of a novel radiological course Co-operative Learning In Clinical Radiology (CLICR) are presented in this article.Materials and methods
A novel radiological teaching course (CLICR course), which combines different innovative teaching elements, was established and integrated into the medical curriculum. Radiological case vignettes were created for three clinical teaching modules. By using a PC with PACS (Picture Archiving and Communication System) access, web-based databases and the CASUS platform, a problem-oriented, case-based and independent way of learning was supported as an adjunct to the well established radiological courses and lectures. Student evaluations of the novel CLICR course and the radiological block course were compared.Results
Student evaluations of the novel CLICR course were significantly better compared to the conventional radiological block course. Of the participating students 52% gave the highest rating for the novel CLICR course concerning the endpoint overall satisfaction as compared to 3% of students for the conventional block course. The innovative interactive concept of the course and the opportunity to use a web-based database were favorably accepted by the students. Of the students 95% rated the novel course concept as a substantial gain for the medical curriculum and 95% also commented that interactive working with the PACS and a web-based database (82%) promoted learning and understanding.Conclusion
Interactive, case-based teaching concepts such as the presented CLICR course are considered by both students and teachers as useful extensions to the radiological course program. These concepts fit well into competence-oriented curricula. 相似文献6.
Patric Kr?pil Rotem S. Lanzman Falk R. Miese Dirk Blondin Joachim Winter Axel Scherer G��nter F��rst 《Cardiovascular and interventional radiology》2011,34(2):345-351
We report on percutaneous catheter procedures in the operating room (OR) to assist complicated manual extraction or insertion
of pacemaker (PM) and implantable cardioverter defibrillator leads. We retrospectively reviewed complicated PM revisions and
implantations performed between 2004 and 2009 that required percutaneous catheter procedures performed in the OR. The type
of interventional procedure, catheter and retrieval system used, venous access, success rates, and procedural complications
were analyzed. In 41 (12 female and 29 male [mean age 62 ± 17 years]) of 3021 (1.4%) patients, standard manual retrieval of
old leads or insertion of new leads was not achievable and thus required percutaneous catheter intervention for retrieval
of misplaced leads and/or recanalisation of occluded central veins. Thirteen of 18 (72.2%) catheter-guided retrieval procedures
for misplaced (right atrium [RA] or ventricle [RV; n = 3], superior vena cava [n = 2], brachiocephalic vein [n = 5], and subclavian vein [n = 3]) lead fragments in 16 patients were successful. Percutaneous catheter retrieval failed in five patients because there
were extremely fixed or adhered lead fragments. Percutaneous transluminal angiography (PTA) of central veins for occlusion
or high-grade stenosis was performed in 25 patients. In 22 of 25 patients (88%), recanalization of central veins was successful,
thus enabling subsequent lead replacement. Major periprocedural complications were not observed. In the case of complicated
manual PM lead implantation or revision, percutaneous catheter-guided extraction of misplaced lead fragments or recanalisation
of central veins can be performed safely in the OR, thus enabling subsequent implantation or revision of PM systems in the
majority of patients. 相似文献
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Benedikt?Michael?SchaarschmidtEmail author Johannes?Boos Christian?Buchbender Patric?Kr?pil Feride?Kr?pil Rotem?Shlomo?Lanzman Guenter?Fürst Wolfram?Trudo?Knoefel Gerald?Antoch Christoph?Thomas 《European radiology》2018,28(8):3221-3227
Purpose
To analyse technical success, complications, and short- and intermediate-term outcomes after heparin-bonded stent graft implantation for the treatment of major abdominal vessel injury after upper abdominal surgery.Methods
This retrospective, IRB-approved analysis included 29 consecutive patients (female: n = 6, male: n = 23, mean age 65.9 ± 11.2 years). All patients underwent angiography and attempted heparin-bonded stent-graft implantation because of a major visceral arterial injury after upper abdominal surgery. Electronic clinical records, angiographic reports and imaging datasets were reviewed to assess technical success and complications. Telephone interviews were performed to obtain follow-up information and to estimate short- (> 30 days) and intermediate-term (> 90 days) outcomes.Results
Successful stent graft placement was achieved in 82.8% (24/29). Peri-interventional complications were observed in 20.7% (6/29) and delayed, angiography-associated complications were observed in 34.5% (10/29) of the patients. Symptomatic re-bleeding occurred in 24.1% (7/29). Short-term survival (> 30 days) was 72.4% (21/29). Intermediate survival (> 90 days) was 37.9% (11/29).Conclusion
Treatment of major vascular injuries with heparin-bonded stent grafts is feasible with a high technical success rate. However, survival depends on the underlying surgical condition, making interdisciplinary patient management mandatory.Key Points
? Stent graft implantation is challenging, but has a high technical success rate. ? Complications are frequent but surgical conversion is rarely necessary. ? Survival depends on the underlying surgical condition causing the vascular injury. ? Interdisciplinary management is crucial for the survival of these patients.10.
CT angiography of the aorta using 80 kVp in combination with sinogram‐affirmed iterative reconstruction and automated tube current modulation: Effects on image quality and radiation dose 下载免费PDF全文