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Pache G Grohmann J Bulla S Arnold R Stiller B Schlensak C Langer M Blanke P 《European journal of radiology》2011,80(3):e440-e445
PurposeTo investigate feasibility and image quality and to calculate radiation dose estimates for computed tomography angiography (CTA) of the great thoracic vessels in infants and toddlers with congenital heart disease (CHD) using end-systolic prospective electrocardiography-triggered sequential dual-source data acquisition.MethodsThis study was institutional review board approved; informed consent was obtained. Twenty children (age 1.2 ± 1.1 years) underwent 22 prospective ECG-triggered sequential dual-source CTA examinations (Somatom Definition, Siemens) with tube current (250 mAs/rot) centered at 250 ms past the R-peak in the cardiac cycle (end-systole). Tube voltage was set to 80 kV. Image quality was evaluated by two readers independently using a four-point grading scale (4 = excellent, 1 = non-diagnostic). Radiation dose estimates were calculated from the dose-length-product (DLP).ResultsAll CT images showed diagnostic image quality (mean score 3.67 ± 0.67, κ = 0.85). Stair-step artifacts were present in one and breathing artifacts in 4 patients, with neither impairing diagnostic image quality. Mean heart rate (bpm) was 107.6 ± 12.1 (76–130), mean heart rate variability (bpm) was 2.5 ± 2.0 (1–9). Mean scan length (mm) was 90.7 ± 22.7 (50–134). Mean estimated effective dose was 0.32 ± 0.11 mSv.ConclusionProspective ECG-triggered sequential dual source CTA is feasible in infants and toddlers with CHD, thereby allowing almost motion-free imaging of the great thoracic vessels with the benefit of a low radiation dose. 相似文献
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Leonhartsberger N Ramoner R Aigner F Stoehr B Pichler R Zangerl F Fritzer A Steiner H 《BJU international》2011,108(10):1603-1607
Study Type – Diagnostic (exploratory cohort) Level of Evidence 2b What’s known on the subject? and What does the study add? Leydig cell tumours (LCTs) of the testis are rare tumours, accounting for 1–3% of all testicular neoplasms. Our data indicate that using scrotal ultrasound with high resolution imaging in routine checkups leads to an earlier detection of LCTs. Most patients underwent an organ‐sparing surgery and no androgen deprivation was observed.
OBJECTIVE
? To report an observed high frequency of Leydig cell tumours (LCTs) diagnosed at our centre.PATIENTS AND METHODS
? Charts of all patients who underwent surgery for a testicular tumour between 1999 and 2008 at our department were searched and data from patients with LCT were collected. ? Before surgery all patients underwent ultrasound and complete staging. In all but two patients with LCT an organ‐sparing surgery was performed. Surgery was performed under ultrasound or palpation guidance. ? All patients underwent postoperative follow‐up. We retrospectively reviewed surgical technique, histology, epidemiology and outcome in all LCT patients.RESULTS
? In the study period, 197 testicular tumours were surgically removed of which 29 were diagnosed as LCT (14.7% of 197; further study group) in 25 patients. Mean age of patients with LCT was 45 years (range 21–68 years). ? Tumour size ranged from 1.2 to 80 mm (mean 10.23 mm). In two patients (8%) the lesion was palpable whereas incidental diagnosis was made in seven patients (28%). ? In the remaining patients diagnosis was made by ultrasound performed for testicular pain (six patients, 24%) or during infertility or erectile dysfunction evaluation (10 patients, 40%). ? Definitive histology reported no malignant histopathological features in all but one patient; this particular patient experienced tumour progression after 2 months and died from advanced disease 1 year later. All other patients are free of disease after a mean follow up of 56 months (range 7–93 months). ? During this period one patient developed a second LCT on the contralateral side; another patient had a recurrence within the same testicle, but on the opposite pole. Both underwent a subsequent organ‐sparing tumour resection.CONCLUSION
? The percentage of LCT (14.7% of all testicular tumours removed) was significantly higher than expected from the literature. One possible explanation for this phenomenon is the increasing use of better ultrasound technology and the subsequent increased detection of small nodules that have not been found in historical series. Use of ‘observation‐only’ for very small lesions detected at infertility clinics is under debate. 相似文献996.
997.
Claire Bernard Laurent Kodjikian Brigitte Bancel Sylvie Isaac Christiane Broussolle Pascal Seve 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2013,251(3):855-860
Purpose
To assess the usefulness of a labial salivary gland biopsy (LSGB) in subsets of patients with uveitis.Methods
A retrospective study of 115 consecutive patients with uveitis for whom a LSGB had been done because of suspected ocular sarcoidosis (n?=?86) or unexplained uveitis (n?=?29). Eighty-six patients had a suspicion of ocular sarcoidosis because of ocular features (n?=?67), an elevated angiotensin converting enzyme (ACE) (n?=?29), or because of CT findings (n?=?32) suggestive of sarcoidosis. The biopsy results were analyzed together with their ophthalmological features and the results of other relevant examinations, such as the serum levels of ACE and a chest radiography or a CT scan.Results
Six of the 115 patients (5.2 %) with uveitis had sarcoid granulomas on the LSGB. At the end of the study, 32 patients had proven sarcoidois while 22 patients were considered as having either indeterminate or presumed sarcoidosis, according to the criteria of Abad et al. A raised ACE (p?=?0.016) and a compatible radiology (p?=?0.033) were related to a positive LSGB test, but not to the features of uveitis. Granulomas were only found in the LSGB of the patients with an elevated ACE or compatible CT scans.Conclusions
In this study, the LSGB sensitivity (18.75 %) in the patients with proven sarcoidosis appears to be lower than in other reports. Our results suggest that this investigation is a possible method of tissue diagnosis in patients with raised ACE and/or CT scan pattern compatible with sarcoidosis, and should not be performed in patients with unexplained uveitis or because of their ophthalmological features. 相似文献998.
Bancel B Esteve J Souquet JC Toyokuni S Ohshima H Pignatelli B 《World journal of gastroenterology : WJG》2006,12(7):1005-1012
AIM:To investigate the extent of oxidative stress in pre-neoplastic and neoplastic gastric mucosa in relation totheir pathological criteria and histological subtypes.METHODS:A total of 104 gastric adenocarcinomas from98 patients(88 infiltrative and 16 intraepithelial tumors)were assessed immunohistochemically for expression ofiNOS and occurrence of nitrotyrosine(NTYR)-containingproteins and 8-hydroxy-2'-deoxyguanosine(8-OH-dG)-containing DNA,as markers of NO production anddamages to protein and DNA.RESULTS:Tumor cells staining for iNOS,NTYR and8-OH-dG were detected in 41%,62% and 50% ofinfiltrative carcinoma,respectively.The three markerswere shown for the first time in intraepithelial carcinoma.The expression of iNOS was significantly more frequentin tubular carcinoma(TC)compared to diffuse carcinoma(DC)(54% vs 18%;P=0.008)or in polymorphouscarcinoma(PolyC)(54% vs 21%;P=0.04).NTYRstaining was obviously more often found in TC thanthat in PolyC(72% vs 30%;P=0.03).There was atendency towards a higher rate of iNOS staining whendistant metastasis(pM)was present.In infiltrativeTC,the presence of oxidative stress markers was notsignificantly correlated with histological grade,density ofinflammation,the depth of infiltration(pT),lymph nodesdissemination(pN)and pathological stages(pTNM). CONCLUSION:The iNOS-oxidative pathway may playan important role in TC,but moderately in PolyC and DC.DNA oxidation and protein nitration occur in the threesubtypes.Based on the significant differences of NTYRlevels,TC and PolyC appear as two distinct subtypes. 相似文献
999.
Guillaume Gorincour Audrey Aschero Catherine Desvignes François Portier Brigitte Bourlière-Najean Alix Ruocco-Angari Philippe Devred Nathalie Colavolpe Bertrand Roquelaure Arnaud Delarue Philippe Petit 《Pediatric radiology》2010,40(6):920-926
Approximately one fourth of cases of inflammatory bowel disease (IBD) occur during childhood and children are more prone than their adult counterparts to have severe disease at presentation. To investigate these diseases MR imaging is no longer an emerging tool. Numerous reviews and articles have been published on this topic underlying the advances of imaging but also the complexity and the financial impact on management of such diseases. In children it seems reasonable to consider US as the first imaging examination to perform, especially when the diagnosis of IBD is unknown. However, we believe that recent and future technical progress, especially the ability of MR to display reproducible data, and the need for gold standard evaluation of new medical therapies will increase the role of MR enterography. 相似文献
1000.