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41.
Localization and determination of infarct size by Gd-Mesoporphyrin enhanced MRI in dogs 总被引:2,自引:0,他引:2
Paul Herijgers Sarra K. Laycock Yicheng Ni Guy Marchal Jan Bogaert Hilde Bosmans Carine Petr´ Willem Flameng 《The International Journal of Cardiac Imaging》1997,13(6):499-507
Background: Accurate localization and sizing of a myocardial infarction are necessary for clinical decision making and even more in research. Gd-Mesoporphyrin enhanced magnetic resonance imaging (MRI) was recently shown to specifically delineate necrosis in liver tumors, renal and muscle necrosis and myocardial infarction in rats. In this study, we investigated this technique's potential to accurately delineate myocardial infarction in a larger animal species, the dog. Methods: Myocardial infarction was induced in 8 dogs by ligation of the left anterior descending coronary artery, 4 of which were reperfused after 3 hr. Gd-Mesoporphyrin (0.05 mmol/kg) was injected intravenously 210 min after the onset of ischemia (n = 6) or after 24 hr in 2 dogs with non-reperfused infarctions. MRI was performed 10 hr. after administration of Gd-Mesoporphyrin. In vivo MRI consisted of EKG-triggered, respiratory gated T1-weighted spin echo and segmented turboFLASH long and short axis measurements. Post-mortem, a spin echo short axis measurement was repeated. Infarct size was determined planimetrically by TTC staining of left ventricular slices. Results: In all instances, there was a very close qualitative agreement between the MRI and TTC defined myocardial infarction. Quantitatively, the linear regression from post-mortem MRI to TTC determined infarct size yielded a result very close to the line of identity (regression coefficient: 0.980 ± 0.026, p<0.000001, adjusted R2 = 0.964). Conclusion: We conclude that Gd-Mesoporphyrin enhanced MRI is a promising tool for the accurate delineation of myocardial infarction. 相似文献
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Pauwels R Beinsberger J Stamatakis H Tsiklakis K Walker A Bosmans H Bogaerts R Jacobs R Horner K;The SEDENTEXCT Project Consortium 《Oral surgery, oral medicine, oral pathology and oral radiology》2012,114(1):127-135
OBJECTIVE: The purpose was to evaluate the perceived spatial and contrast resolution for a wide range of cone-beam computed tomography (CBCT) devices. STUDY DESIGN: A customized polymethyl methacrylate (PMMA) phantom was developed. Inserts containing a line-pair and rod pattern were used. The phantom was scanned with 13 CBCT devices and 1 multislice CT (MSCT) device using a variety of scanning protocols. The images were presented to 4 observers for scoring. RESULTS: The observer scores showed excellent agreement. A wide range was seen in image quality between CBCT exposure protocols. Compared with the average CBCT scores, the MSCT protocols scored lower for the line-pair insert but higher for the rod insert. CONCLUSIONS: CBCT devices are generally suitable for the visualization of high-contrast structures. Certain exposure protocols can be used for depicting low-contrast structures or fine details. The user should be able to select appropriate exposure protocols according to varying diagnostic requirements. 相似文献
46.
Christel Vanroy Dirk Vissers Yves Vanlandewijck Hilde Feys Steven Truijen Marc Michielsen 《Topics in stroke rehabilitation》2013,20(2):98-105
Background: Despite confirmed reduced physical activity (PA) after stroke in various stages of recovery, the type of activities stroke patients executed and the time spent at different activity levels have not been sufficiently verified with stroke-validated assessment tools.Design: Observational study.Objective: To determine PA of sub-acute stroke patients hospitalized in a rehabilitation centre (HOS) compared to chronic home-living stroke patients (HOM) using objective and self-reported measures during 2 weekdays and 1 weekend day.Methods: Fifteen HOS and 15 HOM patients wore a Sense Wear Pro 2 accelerometer (METs*minutes/24 h) and a knee-worn pedometer Yamax Digi Walker SW 200 (steps) and filled in a coded activity diary (kcal/24 h; METs*minutes/24 h) during three consecutive days.Results: In HOM significantly more steps (stepstotal HOM = 18722.6 ± 10063.6; stepstotal HOS = 7097.8 ± 5850.5) and higher energy expenditure (EE) levels (EEtotal HOM = 7759.34 ± 2243.04; EEtotal HOS = 5860.15 ± 1412.78) were measured. In this group less moderate activity (≥3–6 ≤ METs) was performed on a weekday (pday1 = 0.006; pday2 = 0.027) and in total (p = 0.037). Few therapy hours (physical, occupational and speech therapy, and psychological support) were provided in HOM compared to HOS (p < 0.001). Vigorous activities were only seen in HOM. In both groups few patients executed sport activities.Conclusions: In HOM significantly more steps were performed and higher EE values were measured. However, participation in moderate activities and time spent on therapy were less in HOM. Evaluating PA with quantitative measures is feasible in both chronic home-living and sub-acute hospitalized patients with stroke. 相似文献
47.
Hrubos-Str?m H Einvik G Nordhus IH Randby A Pallesen S Moum T Omland T Dammen T 《The European respiratory journal》2012,40(2):400-407
Community-based studies that measure both psychiatric diagnoses and obstructive sleep apnoea (OSA) are lacking. This study reports current psychiatric disorders in community-dwelling adults at high risk for OSA identified by the Berlin Questionnaire. Furthermore, associations between OSA and current psychiatric disorders, unadjusted and adjusted for putative confounders, are reported. A subsample of the Akershus Sleep Apnoea Project consisting of 290 adults, aged 30-65 yrs, with positive Berlin Questionnaire screening underwent the Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders, version IV and polysomnography. Auxiliary analyses of depression are provided. The median apnoea/hypopnoea index score in the sample was 7.7 (interquartile range 2.4-22.2). Major depressive disorder, current anxiety and somatoform pain disorder were diagnosed in 12.4%, 14.8% and 19.3% of participants, respectively. At least one psychiatric disorder was diagnosed in 110 participants. The odds ratio of participants with OSA having a psychiatric disorder compared with participants without OSA was 0.54 (95% CI 0.33-0.88). A negative association did not exist among Berlin Questionnaire low-risk participants. In conclusion, more than one-third of participants in a community-based, Berlin Questionnaire high-risk sample were diagnosed with a psychiatric disorder. A negative association between OSA and psychiatric morbidity was found. 相似文献
48.
Mandl P Naredo E Conaghan PG D'Agostino MA Wakefield RJ Bachta A Backhaus M Hammer HB Bruyn GA Damjanov N Filippucci E Grassi W Iagnocco A Jousse-Joulin S Kane D Koski JM Möller I De Miguel E Schmidt WA Swen WA Szkudlarek M Terslev L Ziswiler HR Ostergaard M Balint PV 《Rheumatology (Oxford, England)》2012,51(1):184-190
49.
Ultrasound (US) is a valid and reliable imaging tool for evaluation of joint and tendon inflammation as well as cartilage and erosions in patients with rheumatoid arthritis (RA). Synovitis is usually scored semiquantitatively for both gray scale synovitis and power Doppler activity, and use of an atlas for US scoring has shown excellent reliability. Several scores are shown to be responsive to medical treatment, but the optimal joint/tendon score is to be explored. Doppler activity may be quantified by use of pixel counts and flow may be examined by use of resistive index. US-guided injections are better tolerated and have increased efficacy, as compared with palpation guidance, and should thus be included in rheumatologic practice. Different methods such as three-dimensional US, contrast-enhanced US and fusion imaging methods are all possible US approaches that may be used in treatment of RA patients in the future. 相似文献
50.
Kari Bø Gunvor Hilde Jette Stær Jensen Franziska Siafarikas Marie Ellstrøm Engh 《International urogynecology journal》2013,24(12):2065-2070