• Journal of radiological science and technology
• /
• v.42 no.5
• /
• pp.351-356
• /
• 2019

This study aimed to determine whether there was a difference in measurements between North American Symptomatic Carotid Endarterectomy Trial(NASCET) and Warfarin-Aspirin Symptomatic Intracranial Disease(WASID) methods that measure the middle cerebral artery stenosis in Digital Subtraction Angiography (DSA) and Magnetic Resonance Angiography (MRA). It involved 24 patients who had completed both DSA and MRA among patients with Middle Cerebral Artery (MCA) stenosis. The Middle Cerebral Artery (MCA) stenosis was measured using the NASCET and WASID methods through a retrospective analysis. For the NASCET and WASID methods, they performed measurements on normal blood vessels located far from and close to the stenosis, respectively. The mean value and standard deviation of the Digital Subtraction Angiography (DSA) measured by the NASCET method were 59.23% and 13.27%. On the other hand, those of the Digital Subtraction Angiography (DSA) measured by the WASID method were 66.64% and 12.47%. And, the mean value and standard deviation of the Magnetic Resonance Angiography (MRA) measured by the NASCET method were 49.82% and 12.06%. By contrast, those of the Magnetic Resonance Angiography (MRA) measured by the WASID method were 56.63% and 10.67%. All the p-values obtained by the Pearson and Spearman correlation tests in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) were <0.01. In conclusion, this study suggests that both the NASCET and WASID methods to measure the middle cerebral artery stenosis in the Digital Subtraction Angiography (DSA) and the Magnetic Resonance Angiography (MRA) can be used if they are not used interchangeably.

• Journal of Biomedical Engineering Research
• /
• v.27 no.2
• /
• pp.53-58
• /
• 2006

In this study, transverse relaxation time (T2) measurement and the evaluation of the characteristics of the spectral peak related to stomach tissue metabolites were performed using ex vivo proton magnetic resonance spectroscopic imaging (MRSI) at 1.5-T MRI/S instruments. Thirty-two gastric tissues resected from 12 patients during gastric cancer surgery, of which 19 were normal tissue and 13 were cancerous tissue, were used to measure the $T_2$ of the magnetic resonance spectroscopy (MRS) peaks. The volume of interest data results from the MRSI measurements were extracted from the proper muscle (MUS) layer and the composite mucosa/submucosa (MC/SMC) layer and were statistically analyzed. MR spectra were acquired using the chemical shift imaging (CSI) point resolved spectroscopy (CSI-PRESS) technique with the parameters of pulse repetition time (TR) and echo times (TE) TR/(TE1,TE2)=1500 msec/(35 msec, 144 msec), matrix $size=24{\times}24$, NA=1, and voxel $size=2.2{\times}2.2{\times}4mm^3$. In conclusion, the measured $T_2$ of the metabolite peaks, such as choline (3.21ppm) and lipid (1.33ppm), were significantly decreased (p<0.01 and p<0.05, respectively) in the cancerous stomach tissue.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.8
• /
• pp.1063-1068
• /
• 2000

Objectives : To determine the contribution of cranial magnetic resonance angiography(MRA) for the evaluation of patients with ischemic cerebrovascular accident. Methods : Magnetic resonance image(MRI) and MRA studies performed on 34 patients with ischemic stroke were retrospectively reviewed with the clinical records. Results : There were 9 transient ischemic attacks and 25 completed strokes in our series. Twenty-three of 34 MRA examinations(68%) were positive for stenosis or occlusion. The distribution of stenotic or occlusive vascular lesions were correlated with the location of infarction in 22 of the 23 positive cases(96%). MRA provided additional information not obtained from the MRI in 19 cases(56%). Conclusions : Vascular lesions demonstrated on intracranial MRA show a high correlation with infarct distribution. MRA provided information adjunctive to conventional MRI in a majority of cases. We conclude that MRA is an important noninvasive component of the complete evaluation of ischemic stroke.

• Investigative Magnetic Resonance Imaging
• /
• v.20 no.2
• /
• pp.95-104
• /
• 2016

Purpose: To evaluate the knee joint after double-bundle anterior cruciate ligament (ACL) reconstruction with three-dimensional (3D) isotropic magnetic resonance (MR) image, and to directly compare the ACL graft findings on 3D MR with the clinical results. Materials and Methods: From January 2009 to December 2014, we retrospectively reviewed MRIs of 39 patients who had reconstructed ACL with double bundle technique. The subjects were examined using 3D isotropic proton-density sequence and routine two-dimensional (2D) sequence on 3.0T scanner. The MR images were qualitatively evaluated for the intraarticular curvature, graft tear, bony impingement, intraosseous tunnel cyst, and synovitis of anteromedial and posterolateral bundles (AMB, PLB). In addition anterior tibial translation, PCL angle, PCL ratio were quantitatively measured. KT arthrometric values were reviewed for anterior tibial translation as positive or negative. The second look arthroscopy results including tear and laxity were reviewed. Results: Significant correlations were found between an AMB tear on 3D-isotropic proton density MR images and arthroscopic proven AMB tear or laxity (P < 0.05). Also, a significant correlation was observed between increased PCL ratio on 3D isotropic MRI and the arthroscopic findings such as tear, laxities of grafts (P < 0.05). KT arthrometric results were found to be significantly correlated with AMB tears (P < 0.05) and tibial tunnel cysts (P < 0.05). Conclusion: An AMB tear on 3D-isotropic MRI was correlated with arthroscopic results qualitatively and quantitatively. 3D isotropic MRI findings can aid the evaluation of ACL grafts after double bundle reconstruction.

• Journal of radiological science and technology
• /
• v.45 no.1
• /
• pp.11-17
• /
• 2022

This study was purpose to quantitative assessment of the resolution characteristics by using American college of radiology(ACR) phantom for magnetic resonance imaging (MRI). The MRI equipment was used (Achiva 3.0T MRI, Philips system, Netherlands) and the head/neck matrix shim SENSE head coil were 32 channels(elements) receive MR coil. And the MRI equipment was used (Discovery MR 750, 3.0T MRI, GE medical system, America) and the head/neck matrix shim MC 3003G-32R 32-CH head coil were receive MR coil. As for the modulation transfer function(MTF) comparison result by using ACR magnetic resonance imaging phantom, the MTF value of the ACR standard T2 image in GE equipment is 0.199 when the frequency is 1.0 mm^-1 and the MTF value of the hospital T2 image in Philips equipment is 0.528. It was used efficiently by using a general sequence more than the standard sequence method using the ACR phantom. In addition it is significant that the quantitative quality assurance evaluation method for resolution characteristics was applied mutatis mutandis, and the result values of the physical image characteristics of the 3.0T MRI device were presented.

• Journal of Biosystems Engineering
• /
• v.24 no.6
• /
• pp.531-538
• /
• 1999

비파괴 품질 평가 기술인 핵 자기공명 분광법과 자기공명영상을 이용하여 소고기의 내부 구조를 분석하였다. 이완 상수 T$_1$과 T$_2$가 육류의 내부 구조와 관계가 있음을 보였다. 근육부분의 면적 비율이 증가할수록 T$_1$이 증가했다. 지방 부분의 T$_2$는 배 내부 부분의 T$_2$와 비슷한 값을 보였다. 자기공명 영상을 이용하여 육류의 원하는 부위의 T$_2$를 측정할 수 있는 방법을 구하였다. 근육 부분의 T$_2$가 길었으며 지방 부분의T$_2$가 짧았다. 부위별로 최적의 신호를 얻을 수 있는 자기공명영상 인자 TR과 TE를 구하였다. 자기공명영상을 이용하여 근육, 지방 그리고 뼈 성분에 따른 육류의 품질을 비파괴적으로 평가할 수 있는 가능성을 보여주었다.

• Imaging Science in Dentistry
• /
• v.42 no.1
• /
• pp.13-18
• /
• 2012

Purpose : The aim of this study was to investigate the effect of the autologous blood injection (ABI) for chronic recurrent temporomandibular joint (TMJ) dislocation using magnetic resonance imaging (MRI). Materials and Methods : ABI was applied to 14 patients who had chronic recurrent TMJ dislocation. MRIs of the patients were taken and compared before and one month after the injection. Results : All of the patients had no dislocations of their TMJs on clinical examination one month after the injection. In the pre-injection, unilateral or bilateral TMJ dislocations were observed on MRIs in all patients. One month after the injection, TMJ dislocations were not observed in MRI evaluation of any patients. A significant structural change that caused by ABI was not observed. Conclusion : The procedure was easy to perform and it caused no foreign body reaction. However, it was unclear how the procedure prevented the dislocation.

• Investigative Magnetic Resonance Imaging
• /
• v.20 no.1
• /
• pp.61-65
• /
• 2016

Osteoid osteoma, a frequent lesions of bone, is usually intraosseous but occasionally subperiosteal. We describe the case of a 19-year-old male with knee pain caused by subperiosteal osteoid osteoma. Radiologic evaluation was performed with radiographic, computed tomography (CT), ultrasonographic (US) and magnetic resonance imaging (MRI). But the preoperative diagnosis of osteoid osteoma was delayed because of unusual imaging findings and atypical symptom. After excisional biopsy, histological examination confirmed the diagnosis of osteoid osteoma. The lesion was treated successfully with CT-guided radiofrequency ablation.

• Investigative Magnetic Resonance Imaging
• /
• v.21 no.1
• /
• pp.34-37
• /
• 2017

A 45-year-old female visited our clinic due to sudden right leg weakness and sensory loss. Brain and spinal cord magnetic resonance imaging showed widespread cavernous malformations. Cavernous malformation in L1 spine area was accompanied by a subacute stage hematoma with perilesional edema. Sensory loss subsided after corticosteroid therapy. Usually, neurologic deficit by spinal cavernous malformation appears more chronically in the adults compared to children. Treatment options are difficult to establish in a case with multiple cavernous malformations. Identifying hemorrhagic lesions by extensive neuroimaging evaluation could be helpful to select the treatment target for cavernous malformation.

• Korean Journal of Veterinary Service
• /
• v.30 no.2
• /
• pp.205-209
• /
• 2007

A protein chip based on surface plasmon resonance (SPR) imaging was developed for measuring classical swine fever virus (CSFV) antibody using a recombinant gp55 protein as an antigen. The diagnostic potential of SPR imaging for detecting antibodies to the CSFV gp55 protein was compared with that of a enzyme -linked immunosorbent assay (ELISA) using 70 pig sera. There was a strong positive correlation between the SPR imaging and ELISA (n=70, r=0.916, p<0.01). Therefore, the SPR imaging, which is a label-free and high-through put method, is expected to be a valuable tool in the serodiagnosis of CSFV.