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11.
MRI and PET images fusion based on human retina model   总被引:1,自引:0,他引:1  
The diagnostic potential of brain positron emission tomography (PET) imaging is limited by low spatial resolution. For solving this problem we propose a technique for the fusion of PET and MRI images. This fusion is a trade-off between the spectral information extracted from PET images and the spatial information extracted from high spatial resolution MRI. The proposed method can control this trade-off. To achieve this goal, it is necessary to build a multiscale fusion model, based on the retinal cell photoreceptors model. This paper introduces general prospects of this model, and its application in multispectral medical image fusion. Results showed that the proposed method preserves more spectral features with less spatial distortion. Comparing with hue-intensity-saturation (HIS), discrete wavelet transform (DWT), wavelet-based sharpening and wavelet-à trous transform methods, the best spectral and spatial quality is only achieved simultaneously with the proposed feature-based data fusion method. This method does not require resampling images, which is an advantage over the other methods, and can perform in any aspect ratio between the pixels of MRI and PET images.  相似文献   
12.
目的探讨SPECT在癫痫诊断中的价值。方法通过比较SPECT、头颅MRI、常规脑电图等辅助检查方法对癫痫患者的检出率,探讨SPECT在诊断中的价值。结果SPECT、常规脑电图、头颅MRI的检出率分别为80.7%,66.7%,47.6%。,结论通过对比SPECT检出率明显高于常规脑电图、MRI的检出率。  相似文献   
13.
Three‐dimensional (3D) information plays an important part in medical and veterinary education. Appreciating complex 3D spatial relationships requires a strong foundational understanding of anatomy and mental 3D visualization skills. Novel learning resources have been introduced to anatomy training to achieve this. Objective evaluation of their comparative efficacies remains scarce in the literature. This study developed and evaluated the use of a physical model in demonstrating the complex spatial relationships of the equine foot. It was hypothesized that the newly developed physical model would be more effective for students to learn magnetic resonance imaging (MRI) anatomy of the foot than textbooks or computer‐based 3D models. Third year veterinary medicine students were randomly assigned to one of three teaching aid groups (physical model; textbooks; 3D computer model). The comparative efficacies of the three teaching aids were assessed through students' abilities to identify anatomical structures on MR images. Overall mean MRI assessment scores were significantly higher in students utilizing the physical model (86.39%) compared with students using textbooks (62.61%) and the 3D computer model (63.68%) (P < 0.001), with no significant difference between the textbook and 3D computer model groups (P = 0.685). Student feedback was also more positive in the physical model group compared with both the textbook and 3D computer model groups. Our results suggest that physical models may hold a significant advantage over alternative learning resources in enhancing visuospatial and 3D understanding of complex anatomical architecture, and that 3D computer models have significant limitations with regards to 3D learning. Anat Sci Educ 6: 216–224. © 2013 American Association of Anatomists.  相似文献   
14.
目的 探讨临床护理路径(CNP)对CT增强患者应用.方法 按临床护理路径制定符合襄阳区人民医院CT增强检查的路径表,对襄州区人民医院208名增强检查患者在检查中按照(CNP)进行护理.结果 临床护理路径应用缩短患者等候时间,减少患者恐惧心理,提高扫描准确性,减少患者射线辐射伤害,同时兼顾成本节约,取得较好效果.结论 按路径表实施CT增强检查,让病人和家属主动参与护理过程,增强病人自我护理意识和能力,减轻患者恐惧心理,同时提高了图像质量,为临床医生提供了详尽的影像资料;每日合理的预约增强检查病人人数,可最大限度减少基层医院增强病人源不足造成的高压注射器和药品的浪费,从而节约了成本.  相似文献   
15.
Abstract

This prospective cohort study described return-to-play (RTP) data for different types of muscle injuries in male elite-level football players in Europe. Eighty-nine European professional teams were followed between 2001 and 2013. Team medical staff recorded individual player exposure and time-loss injuries. A total of 17,371 injuries occurred, including 5603 (32%) muscle injuries. From 2007, we received results from 386 magnetic resonance imaging (MRI) examinations, and radiological grading was performed. A negative MRI was associated with shorter recovery time (6 ± 7 days). Lay-off days were correlated with MRI grading of thigh muscle injuries (< 0.001). Among hamstring injuries, 83% occurred to the biceps femoris, 12% affected the semimembranosus and 5% the semitendinosus. Recurrence rate was higher among biceps femoris injuries (18%) compared with semitendinosus and semimembranosus injuries (2% together). Groin muscle injuries caused shorter median absence (9 days) than hamstring (13 days; < 0.001), quadriceps (12 days; < 0.001) and calf muscle (13 days; < 0.001) injuries. Overall, we found that MRI was valuable for prognosticating RTP, with radiological grading associated with lay-off times after injury. Re-injuries were common in biceps femoris injuries but rare in semitendinosus and semimembranosus injuries.  相似文献   
16.
目的:探讨临床检查和磁共振成像(MRI)对肩袖撕裂的诊断价值。方法:对32例疑似肩袖撕裂患者进行临床检查和MRI检查,后进行关节镜手术检查。以关节镜检查结果为标准,对临床检查和MRI检查诊断肩袖撕裂的结果进行比较分析。结果:关节镜检查发现肩袖撕裂22例,正常10例。以肩关节镜下所见为标准,临床检查诊断肩袖撕裂的敏感性、特异性、准确性分别为86.4%、50%、75%。MRI检查诊断肩袖撕裂的敏感性、特异性、准确性分别为86.4%、70%、81.2%。在关节镜证实肩袖撕裂22例患者中,临床检查阳性率较高的有大结节压痛20例(90.9%),疼痛弧征19例(86.4%),撞击试验17例(77.3%),肩坠落试验14例(63.6%)。结论:MRI诊断对肩袖撕裂的诊断和分级的准确性较高,是诊断肩袖撕裂的有效方法。临床诊断对肩部疼痛的患者及时进行临床检查有重要意义,是诊断肩袖撕裂的基本方法;两种诊断方法的敏感性一致,MRI对肩袖撕裂诊断的特异性和准确性均优于临床诊断。  相似文献   
17.
Objective: Polycystic ovary syndrome (PCOS), a common endocrine-metabolic dysfunction in reproductive-aged women, may be involved in compromised pregnancy and offspring outcomes. This study aimed to investigate whether maternal PCOS affects fetal growth, fetal development, and placental features. Methods: This retrospective case-control study included 60 pregnant women with PCOS (PCOS group) and 120 healthy pregnant women without PCOS (control group). Fetal magnetic resonance imaging (MRI) was performed followed by an ultrasound examination and indications for imaging, including known or suspected fetal pathology, history of fetal abnormality in previous pregnancy or in a family member, and concern for placenta accreta. Fetal MRI images were analyzed for head circumference (HC), abdomen circumference (AC), lung-to-liver signal intensity ratio (LLSIR, a prenatal marker of fetal lung maturity), lengths of liver and kidney diameters in fetuses, and placental relative signal intensity on T2-weighted single-shot fast spin echo (SSFSE) imaging (rSISSFSE), and placental relative apparent diffusion coefficient value (rADC). Data on height and weight of offspring were collected through telephone follow-up. Results: Compared to the control group, the PCOS group showed the following characteristics: (1) smaller biparietal diameter and femur length in fetuses (P=0.026 and P=0.005, respectively), (2) smaller HC in fetuses (evident after 32 weeks; P=0.044), (3) lower LLSIR and smaller dorsoventral length of liver in fetuses (evident before 32 weeks; P=0.005 and P=0.019, respectively), and (4) smaller placental thickness (evident before 32 weeks; P=0.017). No significant differences in placental rSISSFSE or rADC were observed between the groups (all P>0.05). No significant differences in height and weight of offspring during childhood existed between the groups (all P>0.05). Conclusions: There exist alterations of fetal growth, fetal development, and placental features from women with PCOS.  相似文献   
18.
根据有向图的概念和基本定理,将计算机处理过程中的程序流程图抽象为有向图,用于判别流程图的逻辑性及是否存在死锁现象,并用实例进行了判别及仿真验证.  相似文献   
19.
 论文以技术应用领域为分析对象,利用文献计量和Citespace分析工具,提出通过文献所属学科随时间的变化,跟踪分析技术应用领域变迁的方法,并以磁共振成像技术为例,探讨该技术应用领域变迁的过程和原因。研究丰富了技术未来分析的内容。  相似文献   
20.
Using fMRI, we explored the relationship between phonological awareness (PA), a measure of metaphonological knowledge of the segmental structure of speech, and brain activation patterns during processing of print and speech in young readers from 6 to 10 years of age. Behavioral measures of PA were positively correlated with activation levels for print relative to speech tokens in superior temporal and occipito-temporal regions. Differences between print-elicited activation levels in superior temporal and inferior frontal sites were also correlated with PA measures with the direction of the correlation depending on stimulus type: positive for pronounceable pseudowords and negative for consonant strings. These results support and extend the many indications in the behavioral and neurocognitive literature that PA is a major component of skill in beginning readers and point to a developmental trajectory by which written language engages areas originally shaped by speech for learners on the path toward successful literacy acquisition.
Stephen J. FrostEmail:
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