• Title/Summary/Keyword: magnetic resonance imaging

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Usefulness of MRCP in the Diagnosis of Common Bile Duct Dilatation caused by Non-stone or Non-tumorous Conditions (비결석, 비종양성 총담관 확장의 진단에 있어서 자기공명담췌관조영술(MRCP)의 유용성)

  • 정재준;양희철;김명진;김주희;이종태;유형식
    • Investigative Magnetic Resonance Imaging
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    • v.6 no.2
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    • pp.129-136
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    • 2002
  • Purpose : To evaluate the usefulness of MRCP in the diagnosis of the variable causes of common bile duct(CBD) dilatation, except stone or tumor Materials and methods : Twenty-six patients(M:F=15:11, mean age; 62 years) with both MRCP and ERCP were included in this study. Dynamic MRCP(n=12) and contrast-enhanced MRI(n=10) of abdomen were also added. Dilatation of CBD, intrahepatic ducts and pancreatic duct was evaluated, including coexistence of intrahepatic ductal stone, pancreatic pseudocyst, and papillary or papillary edema. The criteria of CBD dilatation was over than 7mm(n= 21, without cholecystectomy) or 10 mm(n=5, with cholecystecto-my) in diameter on T2-weighted coronal image. Results : The mean diameter of CBD was 12.7mm without cholecystectomy(9-19 mm) and 13.0 mm with cholecystectomy(10-15mm), respectively(p 〉0.05). Cholangitis(n=11, 42.3%), chronic pancreatitis(n=8, 30.8%), stenosis of distal CBD(n= 6, 23.1%), periampullary diverticulum(n=3, 11.5%), stenosis of ampulla of Vater(n=2, 7.7%), dysfunction of sphincter of Oddi(n=2, 7.7%), acute focal pancreatitis in the pancreatic head(n=2, 7.7%), papillitis(n=1, 3.8%), pseudocyst in the pancre atic head(n = 1, 3.8%), and ascaris in CBD(n=1, 3.8%) were noted. Pancreatic duct dilatation(n=10, 38.5%) and duodenal diverticulum(n=3, 11.5%) were also seen on MRC P. On dynamic MRCP(12 patients), distal CBD was visualized in 2 patients(16.7%), which was not shown on routine MRCP. Only 1 patient(10.0%) showed papillitis with slightly enhancing papilla on contrast-enhanced MRI (10 patients). Conclusion : MRCP was thought to be helpful in the evaluation of the causes of CBD dilatation, not caused by stone or tumor, especially in the cases of stenosis of distal CBD and chronic pancreatitis, dysfunction of sphincter of Oddi on dynamic MRCP and cholangitis and pericholangitic abnormality on contrast-enhanced MRI.

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Estimation of $T_2{^*}$ Relaxation Times for the Glandular Tissue and Fat of Breast at 3T MRI System (3테슬러 자기공명영상기기에서 유방의 유선조직과 지방조직의 $T_2{^*}$이완시간 측정)

  • Ryu, Jung Kyu;Oh, Jang-Hoon;Kim, Hyug-Gi;Rhee, Sun Jung;Seo, Mirinae;Jahng, Geon-Ho
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.1
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    • pp.1-6
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    • 2014
  • Purpose : $T_2{^*}$ relaxation time which includes susceptibility information represents unique feature of tissue. The objective of this study was to investigate $T_2{^*}$ relaxation times of the normal glandular tissue and fat of breast using a 3T MRI system. Materials and Methods: Seven-echo MR Images were acquired from 52 female subjects (age $49{\pm}12 $years; range, 25 to 75) using a three-dimensional (3D) gradient-echo sequence. Echo times were between 2.28 ms to 25.72 ms in 3.91 ms steps. Voxel-based $T_2{^*}$ relaxation times and $R_2{^*}$ relaxation rate maps were calculated by using the linear curve fitting for each subject. The 3D regions-of-interest (ROI) of the normal glandular tissue and fat were drawn on the longest echo-time image to obtain $T_2{^*}$ and $R_2{^*}$ values. Mean values of those parameters were calculated over all subjects. Results: The 3D ROI sizes were $4818{\pm}4679$ voxels and $1455{\pm}785$ voxels for the normal glandular tissue and fat, respectively. The mean $T_2{^*}$ values were $22.40{\pm}5.61ms$ and $36.36{\pm}8.77ms$ for normal glandular tissue and fat, respectively. The mean $R_2{^*}$ values were $0.0524{\pm}0.0134/ms$ and $0.0297{\pm}0.0069/ms$ for the normal glandular tissue and fat, respectively. Conclusion: $T_2{^*}$ and $R_2{^*}$ values were measured from human breast tissues. $T_2{^*}$ of the normal glandular tissue was shorter than that of fat. Measurement of $T_2{^*}$ relaxation time could be important to understand susceptibility effects in the breast cancer and the normal tissue.

Investigation of the Correlation between Seoul Neuropsychological Screening Battery Scores and the Gray Matter Volume after Correction of Covariates of the Age, Gender, and Genotypes in Patients with AD and MCI (알츠하이머 치매 및 경도인지기능장애 환자에서 나이, 성별, 유전자형을 고려한 뇌 회백질 부피와 표준신경심리검사와의 상관관계 연구)

  • Lee, Seung-Yeon;Yoon, Soo-Young;Kim, Min-Ji;Rhee, Hak Young;Ryu, Chang-Woo;Jahng, Geon-Ho
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.4
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    • pp.294-307
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    • 2013
  • Purpose : To investigate the correlations between Seoul Neuropsychological Screening Battery (SNSB) scores and the gray matter volumes (GMV) in patients with Alzheimer's disease (AD) and mild cognitive impairment (MCI) and cognitively normal (CN) elderly subjects with correcting the genotypes. Materials and Methods: Total 75 subjects were enrolled with 25 subjects for each group. The apolipoprotein E (APOE) epsilon genotypes, SNSB scores, and the 3D T1-weighted images were obtained from all subjects. Correlations between SNSB scores and GMV were investigated with the multiple regression method for each subject group using both voxel-based and region-of-interest-based analyses with covariates of age, gender, and the genotype. Results: In the AD group, Rey Complex Figure Test (RCFT) delayed recall scores were positively correlated with GMV. In the MCI group, Seoul Verbal Learning Test (SVLT) scores were positively correlated with GMV. In the CN group, GMV negatively correlated with Boston Naming Test (K-BNT) scores and Mini-Mental State Examimation (K-MMSE) scores, but positively correlated with RCFT scores. Conclusion: When we used covariates of age, gender, and the genotype, we found statistically significant correlations between some SNSB scores and GMV at some brain regions. It may be necessary to further investigate a longitudinal study to understand the correlation.

The Usefulness of MRCP in the Evaluation of Pancreaticobiliary Diseases in Children (소아에서 담췌관 질환에 대한 자기공명 담췌관조영술의 진단적 유용성)

  • Uhm, Ji Hyun;Lee, Seung Yeon;Chung, Ki Sup
    • Clinical and Experimental Pediatrics
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    • v.45 no.11
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    • pp.1381-1388
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    • 2002
  • Purpose : Magnetic resonance cholangiopancreatography(MRCP) is a noninvasive method for imaging the pancreaticobiliary tree. The aim of this study was to evalute the usefulness of MRCP for the diagnosis of pancreaticobiliary diseases in children. Methods : From October 1996 to May 2001, 67 patients with obstructive jaundice and three patients with chronic recurrent pancreatitis were evaluated with abdominal ultrasonography and MRCP. The final diagnosis was based on the operative and pathologic findings with biopsy specimen including clinical and laboratory findings. Results : A total of 70 patients, consisting of 31 males and 39 females, with a mean age of $2.6{\pm}3.3$ years were studied. The final diagnosis was biliary atresia in 25, neonatal cholestasis in 18, choledochal cyst without anomalous pancreatobiliary duct union(APBDU) in nine, choledochal cyst with APBDU in seven, cholestatic hepatitis in five, chronic recurrent pancreatitis in three, sclerosing cholangitis in two, and secondary biliary cirrhosis in one case. The overall diagnostic accuracy of abdominal ultrasonography was 75.7% and that of MRCP was 97.1%. The sensitivity and specificity of MRCP were 100% and 98% for biliary atresia, 87.5% and 100% for choledochal cyst with APBDU, 100% and 100% for choledochal cyst without APBDU, sclerosing cholangitis and chronic recurrent pancreatitis, respectively. Conclusion : MRCP is a fast, non-invasive and reliable method for diagnosing pancreaticobiliary diseases in children and will be the standard diagnostic procedure in the future.

Quantitative Evaluation of the Corticospinal Tract Segmented by Using Co-registered Functional MRI and Diffusion Tensor Tractography (정상인에서 기능적 뇌 자기공명영상과 확산텐서영상 합성기법을 이용한 피질척수로의 위치에 따른 정량적 분석)

  • Jang, Sung-Ho;Hong, Ji-Heon;Byun, Woo-Mok;Hwang, Chang-Ho;Yang, Dong-Seok
    • Investigative Magnetic Resonance Imaging
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    • v.13 no.1
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    • pp.40-46
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    • 2009
  • Purpose : The purpose of this study was to investigate the quantitative evaluation of the corticospinal tract (CST) at the multiple levels by using functional MRI (fMRI) co-registered to diffusion tensor tractography (DTT). Materials and Methods : Ten normal subjects without any history of neurological disorder participated in this study. fMRI was performed at 1.5 T MR scanner using hand grasp-release movement paradigm. DTT was performed by using DtiStudio on the basis of fiber assignment continuous tracking algorithm (FACT). The seed region of interest (ROI) was drawn in the area of maximum fMRI activation during the motor task of hand grasp-release movement on a 2-D fractional anisotropy (FA) color map, and the target ROI was drawn in the cortiocospinal portion of anterior lower pons. We have drawn five ROIs for the measurement of FA and apparent diffusion coefficient (ADC) along the corona radiata (CR) down to the medulla. Results : The contralateral primary sensorimotor cortex (SM1) was mainly found to be activated in all subjects. DTT showed that tracts originated from SM1 and ran to the medulla along the known pathway of the CST. In all subjects, FA values of the CST were higher at the level of the midbrain and posterior limb of internal capsule (PLIC) than the level of others. Conclusion : Our study showed that co-registered fMRI and DTT has elucidated the state of CST on 3-D and analyzed the quantitative values of FA and ADC at the multiple levels. We conclude that co-registered fMRI and DTT may be applied as a useful tool for clarifying and investigating the state of CST in the patients with brain injury.

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Development of a Korean Standard Structural Brain Template in Cognitive Normals and Patients with Mild Cognitive Impairment and Alzheimer's Disease (정상노인 및 경도인지장애 및 알츠하이머성 치매 환자에서의 한국인 뇌 구조영상 표준판 개발)

  • Kim, Min-Ji;Jahng, Geon-Ho;Lee, Hack-Young;Kim, Sun-Mi;Ryu, Chang-Woo;Shin, Won-Chul;Lee, Soo-Yeol
    • Investigative Magnetic Resonance Imaging
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    • v.14 no.2
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    • pp.103-114
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    • 2010
  • Purpose : To generate a Korean specific brain template, especially in patients with Alzheimer's disease (AD) by optimizing the voxel-based analysis. Materials and Methods : Three-dimensional T1-weighted images were obtained from 123 subjects who were 43 cognitively normal subjects and patients with 44 mild cognitive impairment (MCI) and 36 AD. The template and the corresponding aprior maps were created by using the matched pairs approach with considering differences of age, gender and differential diagnosis (DDX). We measured several characteristics in both our and the MNI templates, including in the ventricle size. Also, the fractions of gray matter and white matter voxels normalized by the total intracranial were evaluated. Results : The high resolution template and the corresponding aprior maps of gray matter, white matter (WM) and CSF were created with the voxel-size of $1{\times}1{\times}1\;mm$. Mean distance measures and the ventricle sizes differed between two templates. Our brain template had less gray matter and white matter areas than the MNI template. There were volume differences more in gray matter than in white matter. Conclusion : Gray matter and/or white matter integrity studies in populations of Korean elderly and patients with AD are needed to investigate with this template.

Changes in Psoas Major and Quadriceps Cross Sectional Area in Elderly People after 12 Weeks of Exercise (고령자를 대상으로 12주간 운동이 대요근 및 대퇴부 근황단면적에 미치는 영향)

  • Tachi, Toshiki;Oguri, Kazuo;Torii, Suguru;Kobayashi, Kando;Fujii, Katsunori;Kim, Jun-Dong;Nho, Ho-Sung
    • Journal of Life Science
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    • v.21 no.1
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    • pp.1-8
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    • 2011
  • The purpose of this study was to investigate whether 12-weeks of movement training would increase the psoas major cross-sectional area (CSA) in senior men and women. Fifty eight men and women aged 65 to 80 years old ($69.6{\pm}3.7$, 30 male, 28 female) were divided into a control (n=19) and exercise group (n=39). Subjects were assessed before and after the training program for stature, body mass, and magnetic resonance imaging of the psoas major and the quadriceps muscle. The experimental group performed exercises using machines designed to improve the movement of the hip at a frequency of twice every week, with a total of 23 trainings in 12-weeks. Magnetic resonance images of both thighs and the abdomen and psoas major were obtained, aimed at 50% of the length of the greater trochanter and the lower edge of the femur and between the fourth (L4) and fifth (L5) lumbars. A 9.4% increase in the psoas major CSA in the training group was observed. In the male and female breakdown, a 11.5% and 8.4% change was observed in males and females, respectively. In the quadriceps, there was no significant statistical improvement in either males or females. Furthermore, in the control group, there was no significant change seen in either the psoas major or the quadriceps. As a result of conducting training that enables upkeep of posture and smooth linkage of the lumbar spine, the pelvis and thighbone, the psoas major CSA of older adults were improved in a short period of time. For this reason, the possibility of improving the psoas CSA, which decreases remarkably with increased age, by improving the linkage of the body trunk is also suggested.

Intracerebral Regional and Vasculature-Specific Distributions of Ischemic Cerebrovascular Diseases: Using MRI and MRA (MRI와 MRA를 이용한 허혈성 뇌혈관 질환의 뇌혈관별 분포에 대한 연구)

  • Kim, Ham-Gyum
    • Journal of radiological science and technology
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    • v.33 no.3
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    • pp.223-230
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    • 2010
  • The purpose of this study was to utilize Magnetic Resonance Imaging (MRI) and Magnetic Resonance Angiography (MRA) to analyze intracerebral regional distributions (hot spot) of ischemic cerebrovascular diseases which were characterized by stenosis and occlusion cerebral vasculature, except for cerebrovascular diseases induced by rupture of cerebral vasculature in terms of Korean people's cerebrovascular diseases, so that it could apply the findings of analysis to clinical practices. This study focused only on analyzing intracerebral regional distributions of ischemic cerebrovascular diseases that are characterized by stenosis and occlusion cerebral vasculature, because there are different etiologic mechanisms of ischemic cerebrovascular diseases like hemorrhagic cerebrovascular diseases (caused by rupture of cerebral vasculature) and cerebral infarction (induced by atheromatous arteriosclerosis). As a result, this study could come to the following findings of analysis: 1. According to sex ratio analysis, it was found that male group comprised larger portion of total 626 subjects in this study than female one (55.0% > 45.0%). 2. According to analysis on actual intracerebral regional distributions of ischemic cerebrovascular diseases, it was found that most subjects (37.5 %) were attacked by such diseases on the right side of cerebral vasculature, which was followed by left side of cerebral vasculature (35.1%) and bilateral cerebral vasculature (27.3%) respectively. 3. According to analysis on actual intracerebral regional distributions of ischemic cerebrovascular diseases, it was found that internal carotid artery (ICA) comprised the largest portion (38.9%) of those distributions, which was followed by middle cerebral artery (MCA, 35.7%), posterior cerebral artery (PCA, 13.4%), anterior cerebral artery (ACA, 6.0%) and vertebral artery (VA, 3.3%) respectively. 4. It was found that there was no subject attacked by any disease on A-com region, and there was only one male subject attacked by cerebrovascular diseases on P-com region. 5. It was found that female group was more susceptible to the attack of cerebrovascular diseases on MCA region than male one (54.6% > 42.2%), which means significant differences depending upon sex on statistical basis ($x^2$ = 9.64, p < .01). 6. It was found that male group was more susceptible to the attack of cerebrovascular diseases on ICA region (56.4% > 46.8%), which means significant differences depending upon sex on statistical basis ($x^2$ = 5.71, p < .05). 7. Moreover, it was also found that male group was more susceptible to the attack of cerebrovascular diseases on BA region (2.3% > 0.4%), which means significant differences depending upon sex on statistical basis ($x^2$ = 4.25, p < .05). 8. However, it was found that there was not any significant difference in intracerebral vasculature-specific distributions of cerebrovascular diseases depending on age of subjects, and stenosis comprised larger portion of cerebrovascular diseases than occlusion.

Humeral Head Decentralization of Preoperative Magnetic Resonance Images and the Treatment of Shoulder Dislocations in Large to Massive Rotator Cuff Tears in Elderly over 65 Years Old (65세 이상 고령의 회전근 개 대파열 및 광범위 파열에 동반된 견관절 탈구의 치료 및 술 전 자기공명영상의 상완골두 탈중심화)

  • Lee, Bong-Ju;Song, In-Soo;Cha, Kihun
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.5
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    • pp.418-426
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    • 2019
  • Purpose: This study analyzed the features of humeral head decentralization in large to massive rotator cuff tears with a shoulder dislocation in the elderly. Moreover, shoulder instability and treatment were reviewed. Materials and Methods: From May 2005 to February 2017, Group A containing 45 cases (45 patients) over 65 years old accompanied by a large or massive rotator cuff tear with a shoulder dislocation and Group B containing 45 cases (45 patients) without a shoulder dislocation were enrolled. The mean ages in Groups A and B were 73.2 and 72.1 years old, and the mean follow-up periods were 30.7 and 31.3 months, respectively. Twenty-one cases (46.7%) in Group A underwent rotator cuff repair, and 8 cases (17.8%) underwent concomitant rotator cuff repair with Bankart repair. Sixteen cases (35.6%) underwent reverse total shoulder arthroplasty for cuff tear arthropathy. 45 cases (100%) in Group B underwent rotator cuff repair. The off-the center and head elevation were measured in the preoperative magnetic resonance imaging (MRI) of Groups A and B. The preoperative and postoperative visual analogue scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score, and University of California Los Angeles (UCLA) score in Groups A and B were compared. Results: In Groups A and B, the mean off-the centers were posterior 7.41 mm and posterior 2.02 mm (p=0.03), and the mean head elevations were superior 6.66 mm and superior 2.44 mm (p=0.02), respectively. The mean ASES scores of Groups A and B were 32.8 and 33.4 before surgery, and 77.1 (p=0.02) and 78.1 (p=0.02) after surgery (p=0.18), respectively. The mean UCLA scores of Groups A and B were 13.1 and 12.8 before surgery, and 28.9 (p=0.02) and 29.5 (p=0.01) after surgery (p=0.15), respectively. Conclusion: Patients over 65 years old with a shoulder dislocation in large to massive rotator cuff tears had higher off-the center and head elevation on the preoperative MRI than those without a shoulder dislocation. This measurement can help predict preceding shoulder instability. Early rotator cuff repairs should be performed and other treatments, such as Bankart repair and reverse total shoulder arthroplasty, should also be considered.

Usefulness of Acoustic Noise Reduction in Brain MRI Using Quiet-T2 (뇌 자기공명영상에서 Quiet-T2 기법을 이용한 소음감소의 유용성)

  • Lee, SeJy;Kim, Young-Keun
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.51-57
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    • 2016
  • Acoustic noise during magnetic resonance imaging (MRI) is the main source for patient discomfort. we report our preliminary experience with this technique in neuroimaging with regard to subjective and objective noise levels and image quality. 60 patients(29 males, 31 females, average age of 60.1) underwent routine brain MRI with 3.0 Tesla (MAGNETOM Tim Trio; Siemens, Germany) system and 12-channel head coil. Q-$T_2$ and $T_2$ sequence were performed. Measurement of sound pressure levels (SPL) and heart rate on Q-$T_2$ and $T_2$ was performed respectively. Quantitative analysis was carried out by measuring the SNR, CNR, and SIR values of Q-$T_2$, $T_2$ and a statistical analysis was performed using independent sample T-test. Qualitative analysis was evaluated by the eyes for the overall quality image of Q-$T_2$ and $T_2$. A 5-point evaluation scale was used, including excellent(5), good(4), fair(3), poor(2), and unacceptable(1). The average noise and peak noise decreased by $15dB_A$ and $10dB_A$ on $T_2$ and Q-$T_2$ test. Also, the average value of heartbeat rate was lower in Q-$T_2$ for 120 seconds in each test, but there was no statistical significance. The quantitative analysis showed that there was no significant difference between CNR and SIR, and there was a significant difference (p<0.05) as SNR had a lower average value on Q-$T_2$. According to the qualitative analysis, the overall quality image of 59 case $T_2$ and Q-$T_2$ was evaluated as excellent at 5 points, and 1 case was evaluated as good at 4 points due to a motion artifact. Q-$T_2$ is a promising technique for acoustic noise reduction and improved patient comfort.