The purpose of this study was to analyze the lesion brightness (image contrast) in multiple MRI sequences in patients with relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), primary progressive MS (PPMS),...The purpose of this study was to analyze the lesion brightness (image contrast) in multiple MRI sequences in patients with relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), primary progressive MS (PPMS), and clinically isolated syndrome (CIS);and to correlate the lesion contrast with lesion volumes and neurological disability. MRI ex- amination at 1.5 T was performed on 80 patients with RRMS, SPMS, PPMS, or CIS. The protocol included T1- and T2-weighted spin echo (SE), fluid attenuated inversion recovery (FLAIR), T1-weighted SE with magnetization transfer preparation, and diffusion weighted imaging (DWI). Contrast was measured between MS lesions and normal appearing white matter. Lesion volume was calculated in T1-weighted- and FLAIR-images. All patients were examined neurologically including evaluation of expanded disability status scale (EDSS) score. Lesion contrast correlated with total brain lesion volume (p = 0.000 - 0.040). In patients with low EDSS, three sequences were able to differentiate between CIS and RRMS. SPMS and PPMS were separated by DWI. Lesion contrast correlated with EDSS score on T1-weighted imaging, with or without magnetization transfer preparation. Patient age correlated with lesion contrasts. Contrast measurements seem limited in radiological and clinical diagnosis of MS in reference to disease course, its activity and progression. The differentiation between MS subgroups might improve at 3 T and could help in leading to earlier treatment of the disease.展开更多
A fast interactive segmentation algorithm of image-sequences based on relative fuzzy connectedness is presented. In comparison with the original algorithm, the proposed one, with the same accuracy, accelerates the seg...A fast interactive segmentation algorithm of image-sequences based on relative fuzzy connectedness is presented. In comparison with the original algorithm, the proposed one, with the same accuracy, accelerates the segmentation speed by three times for single image. Meanwhile, this fast segmentation algorithm is extended from single object to multiple objects and from single-image to image-sequences. Thus the segmentation of multiple objects from complex hackground and batch segmentation of image-sequences can be achieved. In addition, a post-processing scheme is incorporated in this algorithm, which extracts smooth edge with one-pixel-width for each segmented object. The experimental results illustrate that the proposed algorithm can obtain the object regions of interest from medical image or image-sequences as well as man-made images quickly and reliably with only a little interaction.展开更多
文摘The purpose of this study was to analyze the lesion brightness (image contrast) in multiple MRI sequences in patients with relapsing-remitting MS (RRMS), secondary progressive MS (SPMS), primary progressive MS (PPMS), and clinically isolated syndrome (CIS);and to correlate the lesion contrast with lesion volumes and neurological disability. MRI ex- amination at 1.5 T was performed on 80 patients with RRMS, SPMS, PPMS, or CIS. The protocol included T1- and T2-weighted spin echo (SE), fluid attenuated inversion recovery (FLAIR), T1-weighted SE with magnetization transfer preparation, and diffusion weighted imaging (DWI). Contrast was measured between MS lesions and normal appearing white matter. Lesion volume was calculated in T1-weighted- and FLAIR-images. All patients were examined neurologically including evaluation of expanded disability status scale (EDSS) score. Lesion contrast correlated with total brain lesion volume (p = 0.000 - 0.040). In patients with low EDSS, three sequences were able to differentiate between CIS and RRMS. SPMS and PPMS were separated by DWI. Lesion contrast correlated with EDSS score on T1-weighted imaging, with or without magnetization transfer preparation. Patient age correlated with lesion contrasts. Contrast measurements seem limited in radiological and clinical diagnosis of MS in reference to disease course, its activity and progression. The differentiation between MS subgroups might improve at 3 T and could help in leading to earlier treatment of the disease.
文摘A fast interactive segmentation algorithm of image-sequences based on relative fuzzy connectedness is presented. In comparison with the original algorithm, the proposed one, with the same accuracy, accelerates the segmentation speed by three times for single image. Meanwhile, this fast segmentation algorithm is extended from single object to multiple objects and from single-image to image-sequences. Thus the segmentation of multiple objects from complex hackground and batch segmentation of image-sequences can be achieved. In addition, a post-processing scheme is incorporated in this algorithm, which extracts smooth edge with one-pixel-width for each segmented object. The experimental results illustrate that the proposed algorithm can obtain the object regions of interest from medical image or image-sequences as well as man-made images quickly and reliably with only a little interaction.
基金Supported by National Natural Science Foundation of P. R. China (69975011, 60172067, 60133020, 60325208), "863" Program (2002AA144060)Funding of China National Education Ministry, Natural Science Foundation of Guangdong Province (013164)