• Journal of Digital Convergence
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• v.11 no.12
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• pp.599-606
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• 2013

The purpose of this study is to know a clinical usefulness for delineation of articular cartilage compared with 2D TSE-SPIR and 3D FFE-PROSET technique. From January 2013 to september 2013, a total of 30 normal volunteers(12 men and 18 women aged between 35 and 55 years; mean 49.48 years) were studied on a philips 3.0T MRI scanner. As a quantitative analysis, SNRs and CNRs were evaluated by using two methods for delineation of articular cartilage. As a qualitative analysis, image quality was evaluated by special radiological technologist of MRI for image delineation on a three grade. As a results, SNRs and CNRs for articular cartilage were significantly greater for the 3D FFE-PROSET(SNRs: 8.40, 114.02, 9.53, CNRs: 104.49, 139.49) technique compared to 2D TSE-SPIR(SNRs: 4.41, 71.63, 7.34, CNRs: 64.30, 58.41) technique, image quality also was higher for evaluation of 3D FFE-PROSET(2.40) technique(p=0.0021). In conclusion, this study showed that a 3D FFE-PROSET MRI has improved SNRs and CNRs for evaluating of the articular cartilage, these conclusions in the future will be provided useful information in diagnosis of articular cartilage.

• Investigative Magnetic Resonance Imaging
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• v.5 no.2
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• pp.138-148
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• 2001

Purpose : Within a clinically acceptable time frame, we obtained the high resolution MR images of the human brain, knee, foot and wrist from 3T whole-body MRI system which was equipped with the world first 37 active shield magnet. Materials and Methods : Spin echo (SE) and Fast Spin Echo (FSE) images were obtained from the human brain, knee, foot and wrist of normal subjects using a homemade birdcage and transverse electromagnetic (TEM) resonators operating in quadrature and tuned to 128 MHz. For acquisition of MR images of knee, foot and wrist, we employed a homemade saddle shaped RF coil. Topical common acquisition parameters were as follows: matrix=$512{\times}512$, field of view (FOV) =20 cm, slice thickness = 3 mm, number of excitations (NEX)=1. For T1-weighted MR images, we used TR = 500 ms, TE = 10 or 17.4 ms. For T2-weighted MR images, we used TR=4000 ms, TE = 108 ms. Results : Signal to noise ratio (SNR) of 3T system was measured 2.7 times greater than that of prevalent 1.5T system. MR images obtained from 3T system revealed numerous small venous structures throughout the image plane and provided reasonable delineation between gray and white matter. Conclusion The present results demonstrate that the MR images from 3T system could provide better diagnostic quali\ulcorner of resolution and sensitivity than those of 1.5T system. The elevated SNR observed in the 3T high field magnetic resonance imaging can be utilized to acquire images with a level of resolution approaching the microscopic structural level under in vivo conditions. These images represent a significant advance in our ability to examine small anatomical features with noninvasive imaging methods.

• Progress in Medical Physics
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• v.12 no.2
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• pp.113-124
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• 2001

For veterinary imaging diagnosis, we obtained MR images of the canine brain, spine, kidney and pelvis from 3T MRI system which was equipped with the world first 3T active shield magnet. Spin echo (SE) and fast Spin Echo (FSE) images were obtained from the canine brain, spine, kidney and pelvis of normal and sick dogs using a homemade birdcage and transverse electromagnetic (TEM) resonators operating in quadrature and tuned to 128 MHz. In addition, we employed a homemade saddle shaped RF coil. Typical common acquisition parameters were as follows: matrix=512$\times$512, field of view (FOV)=20cm, slice thickness=3 w, number of excitations (NEX)=1. For T1-weighted MR images, we used TR=500 ms, TE=10 or 17.4 ms. For T2-weighted MR images, we used TR=4000 ms, TE=108 ms. Signal to noise ratio (SNR) of 3T system was measured 2.7 times greater than that of prevalent 1.57 system. The high resolution images acquired in this study represent more than a 4-fold increase in in-plane resolution relative to conventional images obtained with a 20 cm field of view and a 5 mm slice thickness. MR images obtained from 3T system revealed numerous small venous structures throughout the image plane and provided reasonable delineation between gray and white matter The present results demonstrate that the MR images from 3T system could provide better diagnostic quality of resolution and sensitivity than those of 1.5T system. The elevated SNR observed in the 3T high field magnetic resonance imaging can be utilized to acquire images with a level of resolution approaching the microscopic structural level under in vivo conditions. These images represent a significant advance in our ability to examine small anatomical features with noninvasive imaging methods. Moreover, MRI technique could begin to apply for veterinary medicine in Korea.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.9
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• pp.117-124
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• 2015

In this paper, we introduce how to control TR, TE physical MR parameters for managing $H_1$ spin's SI(Signal Intensity) which is combined with gadolinium following administration MR agent in T1 effect for diagnostic usefulness. we used MRI phantom made with 0.5 mol Gadoteridol. This phantom was scanned by FSE sequence with different TR, TE parameters. In this study, to make T1 effect, TR was 200, 250, 300, 350, 400, 450, 500, 550, 600 msec. In addition to, TE was 6.2, 12.4, 18.6, 21.6 msec. The results were as follows ; Each RSP(Reaction Starting Point) was 100, 50, 40, 30 mmol in TE 6.2, 12.4, 18.6, 21.6 msec being irrelevant to TR. In MPSI(Max Peak Signal Intensity), 4 mmol was showed in TR 200 msec while peak signal was decreased to low concentration mol in TR 250-600 msec. In terms of RA(Reaction Area), the highest SI was TE 6.2 msec in TR 200-600msec. According to the study, we are able to recognize it is possible to control enhance rates by managing TR and TE of MR parameters; moreover, we expect that enhanced T1 image in MR clinical field can be performed in a practical way with this quantitative data.

• Journal of radiological science and technology
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• v.29 no.3
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• pp.157-165
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• 2006

In order to analyze clinical characteristics like sex- and age-based onset frequency and onset region from vertebral disease cases, this study investigated total 1,291 cases of vertebral disease that were diagnosed via magnetic resonance imaging(MRI) from January to December 2004 at B University Hospital in metropolitan area. For higher diagnostic accuracy in cases of spinal disorder diagnosed, this study analyzed findings from data reading conducted by veteran specialists in diagnostic radiology. But this study excluded uncertain lesion cases, the cases requiring differential diagnosis from other disorders and so on from subjects under analysis. This study employed superconductive 1.5 Tesla SIGNA MR/i for MRI test and basically received resulting images via FSE(fast spin echo). In particular, this study obtained T1 and T2 myelogram with regard to regional characteristics(such as cervical vertebrae, thoracic vertebrae and lumbar vertebra) and imaging characteristics for sagittal and transverse section. As a result, this study came to the following conclusions : 1. In terms of general characteristics of subjects under analysis, male group comprised 53.5% and female 46.5% out of total 1,291 subjects. 2. The regional onset frequency of spinal disorders was converged primarily on lumbar vertebra(65.5%), which was followed by cervical vertebrae(27.3%) and thoracic vertebrae(7.0%) respectively. 3. Top 10 cases with high onset frequency of spinal disorders can be listed as follows : 1) posterior bulging disc 65.8% 2) narrowing of neural foramen 23.8% 3) herniated intervertebral disc (HIVD) 22.4% 4) spinal stenosis 16.7% 5) osteochondrosis 6.4% 6) compression fracture 6.4% 7) facet joint arthropathy 6.2% 8) spondylolisthesis 6.0% 9) spinal cord tumor 3.5% 10) inter body fusion 2.6%