• Title/Summary/Keyword: Diffusion Weighted Image

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Clinical Usefulness of Arterial Spin Labeling Perfusion MR Imaging in Acute Ischemic Stroke (급성 허혈성 뇌경색 환자에서 동맥스핀표지 관류자기공명영상의 유용성)

  • Oh, Keun-Taek;Jung, Hong-Ryang;Lim, Cheong-Hwan;Cho, Young-Ki;Ha, Bon-Chul;Hong, Doung-Hee
    • Journal of radiological science and technology
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    • v.34 no.4
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    • pp.323-331
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    • 2011
  • We evaluated clinical usefulness of Arterial spin labeling perfusion MR imaging on the acute ischemic cerebral infarction patients through this study. We compared 22 patients who were done with DSC imaging and ASL imaging in admitted emergency room with acute ischemic cerebral infarction, with 36 normal comparison persons (DSC image on 21persons, ASL images on 15persons). Siemens Magnetom Verio 3.0T with 12 channel head coil was used for this study. DSC image obtained 4 maps(rCBV, rCBF, rMTT, TTP) through post-processing. For qualitative analysis we compared the area of lesion macro-diagonal with the size of diffusion weighted MR image for rMTT, TTP, rCBF, rCBV, ASL maps. For Quantitative analysis we analyzed significant correlations between less than 3 cm infarction group and normal comparison group using mean relative value of flowing image with Mann-Whitney U test. TTP(95.5%) and rCBF(95.5%) maps showed high recognition rate in qualitative analysis for >3cm infarction group. The rCBF and rCBV map tests were highly related with final stage stroke areas. Mean relative value of infarction group showed a significant correlations in quantitative analysis(p<0.05). As a conclusion, arterial spin labeling image showed high lesion recognition rate in the >3cm infarction group. Mean relative values in quantitative evaluation were used for reference data. If we do more sustainable researches, ASL image will be useful for an early diagnosis of cerebral infarction, determination of the range of ischemic pneumbra and effective treatments.

Dynamic Characteristic Change of the Cerebral Blood Volume in Cats Using Perfusion MR Imaging (MR 관류영상을 이용한 고양이 대뇌 혈류량의 동적특성 변화)

  • 박병래;김학진;전계록
    • Journal of Biomedical Engineering Research
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    • v.25 no.4
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    • pp.243-251
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    • 2004
  • This study was to quantitative analysis compare to dynamic characteristic change of the regional cerebral blood volume (rCBV) after development of cerebral fat embolism in cats using perfusion MR Imaging. Forty-four adult rats were used. Triolein (n = 15), oleic acid (n = 9) and linoleic acid (n = 11) were injected into the internal carotid artery using microcatheter through the transfemoral approach. Polyvinyl alcohol (Ivalon) (n = 9) was injected as a control group. Perfusion MR images were obtained at 30 minutes and 2 hours after embolization, based on T2 and diffusion-weighted images. The data was time-to-signal intensity curve and ΔR$_2$* curve were obtained continuously with the aid of home-maid image proc in.leased significantly at 2 hours compared with those of 30 minutes (P<0.005). In conclusion, cerebral blood flow decreased in cerebral fat embolism immediately after embolization and recovered remarkably in time course. It is thought that clinically informations to dynamic characteristic change of the cerebral hemodynamics to the early finding in cerebral infarction by DWI and PWI

Study on Volume Measurement of Cerebral Infarct using SVD and the Bayesian Algorithm (SVD와 Bayesian 알고리즘을 이용한 뇌경색 부피 측정에 관한 연구)

  • Kim, Do-Hun;Lee, Hyo-Young
    • Journal of the Korean Society of Radiology
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    • v.15 no.5
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    • pp.591-602
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    • 2021
  • Acute ischemic stroke(AIS) should be diagnosed within a few hours of onset of cerebral infarction symptoms using diagnostic radiology. In this study, we evaluated the clinical usefulness of SVD and the Bayesian algorithm to measure the volume of cerebral infarction using computed tomography perfusion(CTP) imaging and magnetic resonance diffusion-weighted imaging(MR DWI). We retrospectively included 50 patients (male : female = 33 : 17) who visited the emergency department with symptoms of AIS from September 2017 to September 2020. The cerebral infarct volume measured by SVD and the Bayesian algorithm was analyzed using the Wilcoxon signed rank test and expressed as a median value and an interquartile range of 25 - 75 %. The core volume measured by SVD and the Bayesian algorithm using was CTP imaging was 18.07 (7.76 - 33.98) cc and 47.3 (23.76 - 79.11) cc, respectively, while the penumbra volume was 140.24 (117.8 - 176.89) cc and 105.05 (72.52 - 141.98) cc, respectively. The mismatch ratio was 7.56 % (4.36 - 15.26 %) and 2.08 % (1.68 - 2.77 %) for SVD and the Bayesian algorithm, respectively, and all the measured values had statistically significant differences (p < 0.05). Spearman's correlation analysis showed that the correlation coefficient of the cerebral infarct volume measured by the Bayesian algorithm using CTP imaging and MR DWI was higher than that of the cerebral infarct volume measured by SVD using CTP imaging and MR DWI (r = 0.915 vs. r = 0.763 ; p < 0.01). Furthermore, the results of the Bland Altman plot analysis demonstrated that the slope of the scatter plot of the cerebral infarct volume measured by the Bayesian algorithm using CTP imaging and MR DWI was more steady than that of the cerebral infarct volume measured by SVD using CTP imaging and MR DWI (y = -0.065 vs. y = -0.749), indicating that the Bayesian algorithm was more reliable than SVD. In conclusion, the Bayesian algorithm is more accurate than SVD in measuring cerebral infarct volume. Therefore, it can be useful in clinical utility.

The Role of Double Inversion Recovery Imaging in Acute Ischemic Stroke

  • Choi, Na Young;Park, Soonchan;Lee, Chung Min;Ryu, Chang-Woo;Jahng, Geon-Ho
    • Investigative Magnetic Resonance Imaging
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    • v.23 no.3
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    • pp.210-219
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    • 2019
  • Purpose: The purpose of this study was to investigate if double inversion recovery (DIR) imaging can have a role in the evaluation of brain ischemia, compared with diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery (FLAIR) imaging. Materials and Methods: Sixty-seven patients within 48 hours of onset, underwent MRI scans with FLAIR, DWI with b-value of 0 (B0) and $1000s/mm^2$, and DIR sequences. Patients were categorized into four groups: within three hours, three to six hours, six to 24 hours, and 24 to 48 hours after onset. Lesion-to-normal ratio (LNR) value was calculated and compared among all sequences within each group, by the Friedman test and conducted among all groups, for each sequence by the Kruskal-Wallis test. In qualitative assessment, signal intensity changes of DIR, B0, and FLAIR based on similarity with DWI and image quality of each sequence, were graded on a 3-point scale, respectively. Scores for detectability of lesions were compared by the McNemar's test. Results: LNR values from DWI were higher than DIR, but not statistically significant in all groups (P > 0.05). LNR values of DIR were significantly higher than FLAIR within 24 hours of onset (P < 0.05). LNR values were significantly different between, before, and after six hours onset time for DIR (P = 0.016), B0 (P = 0.008), and FLAIR (P = 0.018) but not for DWI (P = 0.051). Qualitative analysis demonstrated that detectability of DIR was higher, compared to that of FLAIR within 4.5 hours and six hours of onset (P < 0.05). Also, the DWI quality score was lower than that of DIR, particularly relative to infratentorial lesions. Conclusion: DIR provides higher detectability of hyperacute brain ischemia than B0 and FLAIR, and does not suffer from susceptibility artifact, unlike DWI. So, DIR can be used to replace evaluation of the FLAIR-DWI mismatch.

Gastric Metastasis from Gastric-Type Mucinous Adenocarcinoma of Uterine Cervix: A Case Report (자궁경부 위형 점액샘암종의 위 전이: 증례 보고)

  • Min Hye Kim;Kyeong Ah Kim;Yi Kyeong Chun;Jeong Woo Kim;Jongmee Lee;Chang Hee Lee
    • Journal of the Korean Society of Radiology
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    • v.85 no.2
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    • pp.445-450
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    • 2024
  • Gastric metastasis (GM) from cervical cancer is extremely rare, and only a few cases have been reported in the English literature. Gastric-type mucinous adenocarcinomas (GAS) of the uterine cervix are rare. GAS is an aggressive cancer commonly found in advanced stages; however, GM has not been reported. This study presents a rare case of GM from GAS of the uterine cervix in a 61-year-old female and describes the radiological findings of both the GM and cervical mucinous adenocarcinoma. GM appeared as a poor enhancing submucosal mass. The cervical mucinous adenocarcinoma appeared as an infiltrating mass with poor contrast enhancement. It exhibited mildly high and low signal intensities on the diffusion-weighted image and apparent diffusion coefficient map, respectively. This case is extremely rare and challenging to diagnose; however, if cervical cancer is an human papillomavirus-independent GAS type and a submucosal lesion is found in the stomach, the possibility of metastasis with a pattern similar to our case could be considered.

Decreased White Matter Structural Connectivity in Psychotropic Drug-Naïve Adolescent Patients with First Onset Major Depressive Disorder (정신과적 투약력이 없는 초발 주요 우울장애 청소년 환아들에서의 백질 구조적 연결성 감소)

  • Suh, Eunsoo;Kim, Jihyun;Suh, Sangil;Park, Soyoung;Lee, Jeonho;Lee, Jongha;Kim, In-Seong;Lee, Moon-Soo
    • Korean Journal of Psychosomatic Medicine
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    • v.25 no.2
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    • pp.153-165
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    • 2017
  • Objectives : Recent neuroimaging studies focus on dysfunctions in connectivity between cognitive circuits and emotional circuits: anterior cingulate cortex that connects dorsolateral orbitofrontal cortex and prefrontal cortex to limbic system. Previous studies on pediatric depression using DTI have reported decreased neural connectivity in several brain regions, including the amygdala, anterior cingulate cortex, superior longitudinal fasciculus. We compared the neural connectivity of psychotropic drug naïve adolescent patients with a first onset of major depressive episode with healthy controls using DTI. Methods : Adolescent psychotropic drug naïve patients(n=26, 10 men, 16 women; age range, 13-18 years) who visited the Korea University Guro Hospital and were diagnosed with first onset major depressive disorder were registered. Healthy controls(n=27, 5 males, 22 females; age range, 12-17 years) were recruited. Psychiatric interviews, complete psychometrics including IQ and HAM-D, MRI including diffusion weighted image acquisition were conducted prior to antidepressant administration to the patients. Fractional anisotropy(FA), radial, mean, and axial diffusivity were estimated using DTI. FMRIB Software Library-Tract Based Spatial Statistics was used for statistical analysis. Results : We did not observe any significant difference in whole brain analysis. However, ROI analysis on right superior longitudinal fasciculus resulted in 3 clusters with significant decrease of FA in patients group. Conclusions : The patients with adolescent major depressive disorder showed statistically significant FA decrease in the DTI-based structure compared with healthy control. Therefore we suppose DTI can be used as a bio-marker in psychotropic drug-naïve adolescent patients with first onset major depressive disorder.

High-Resolution Contrast-Enhanced 3D-Spoiled Gradient-Recalled Imaging for Evaluation of Intracranial Vertebral Artery and Posterior Inferior Cerebellar Artery in Lateral Medullary Infarction (고해상도 조영증강 삼차원 회손기울기 회상 영상을 이용한 측면연수경색 환자의 두개내 척추동맥 및 뒤아래소뇌동맥 평가)

  • Yoon, Youngno;Ahn, Sung Jun;Suh, Sang Hyun;Park, Ah Young;Chung, Tae-Sub
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.1
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    • pp.17-24
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    • 2014
  • Purpose : To determine whether high-resolution contrast-enhanced three dimensional imaging with spoiled gradient-recalled sequence (HR-CE 3D-SPGR) plays a meaningful role in the assessment of intracranial vertebral artery (ICVA) and posterior inferior cerebellar artery (PICA) in lateral medullary infarction (LMI). Materials and Methods: Twenty-five patients confirmed with LMI were retrospectively enrolled with approval by the IRB of our institute, and 3T MRI with HR-CE 3D-SPGR and contrast-enhanced magnetic resonance angiography (CE-MRA) were performed. Two radiologists who were blinded to clinical information and other brain MR images including diffusion weighted image independently evaluated arterial lesions in ICVA and PICA. The demographic characteristics, the area of LMI and cerebellar involvement were analyzed and compared between patients with arterial lesion in ICVA only and patients with arterial lesions in both ICVA and PICA on HR-CE 3D-SPGR. Results: Twenty-two of twenty-five LMI patients had arterial lesions in ICVA or PICA on HR-CE 3D SPGR. However twelve arterial lesions in PICA were not shown on CE-MRA. Concurrent cerebellar involvement appeared more in LMI patients with arterial lesion in ICVA and PICA than those with arterial lesion in ICVA alone (p = 0.069). Conclusion: HR-CE 3D-SPGR can help evaluate arterial lesions in ICVA and PICA for LMI patients.

Leukoaraiosis on Magnetic Resonance Imaging Is Related to Long-Term Poor Functional Outcome after Thrombolysis in Acute Ischemic Stroke

  • Choi, Jae-Hyung;Bae, Hyo-Jin;Cha, Jae-Kwan
    • Journal of Korean Neurosurgical Society
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    • v.50 no.2
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    • pp.75-80
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    • 2011
  • Objective : Leukoaraiosis (LA) has been suggested to be related to the poor outcome or the occurrence of symptomatic intracerebral hemorrhage (sICH) after acute ischemic stroke. We retrospectively investigated the influences of LA on long-term outcome and the occurrence of sICH after thrombolysis in acute ischemic stroke (AIS). Methods : In this study, we recruited 164 patients with AIS and magnetic resonance image (MRI)-detected thrombolysis. The presence and extent of LA were assessed using the Fazekas grading system. The National Institutes of Health Stroke Scale score was used to assess the baseline measure of neurologic severity, and the modified Rankin Scale score assessment was used up to 1 year after thrombolysis. Results : Of 164 subjects, 56 (34.2%) showed LA on MRI. Compared to the 108 patients without LA, the patients with LA were of much older age (p<0.01), had a higher prevalence of hypertension (p<0.01), and had a much poorer outcome at 90 days (p=0.05) and 1 yr (p=0.01) after thrombolysis. There were no significant differences in sICH between patients with and without LA on MRI. In univariate analysis for the occurrence of poor outcome at 90 days after thrombolysis, the size of ischemic lesion on diffusion weighted images (DWI), [odds ratio (OR), 1.03; 95% confidence interval (95% CI), 1.01-1.04; p<0.01], recanalization (OR, 0.03; 95% CI, 0.01-0.10; p<0.01), sICH (OR, 12.2; 95% CI, 1.54-95.8), neurologic severity (OR, 1.17; 95% CI, 1.09-1.25; p<0.01), blood glucose level (OR, 1.01; 95% CI, 1.00-1.02; p=0.03), and the presence of LA on MRI (OR, 2.01; 95% CI, 1.04-3.01; p=0.04) were statistically significant. In multivariate analysis, neurologic severity (OR, 1.14; 95% CI, 1.04-1.24; p<0.01), recanalization (OR, 0.03; 95% CI, 0.01-0.11; p<0.01), lesion size on DWI (OR, 1.02; 95% CI, 1.01-1.03; p=0.02), serum glucose level (OR, 1.01; 95% CI; 1.01-1.02; p=0.03), and the presence of LA on MRI (OR, 3.2; 95% CI, 1.22-8.48; p<0.01) showed statistically significant differences. These trends persisted up to 1 yr after thrombolysis. Conclusion : In this study, we demonstrated that the presence of LA on MRI might be related to poor outcome after use of intravenous tissue plasminogen activator in AIS.

Functional MRI of Visual cortex in the Patients with Occipital Lobe Ischemia (후두엽의 허혈성 뇌졸중 환자에서 시각피질의 기능적 자기공명영상)

  • 이영준;정태섭;윤영수;한승한;조영재;배준호
    • Investigative Magnetic Resonance Imaging
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    • v.3 no.2
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    • pp.173-178
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    • 1999
  • Purpose : To evaluate the usefulness of functional MRI (fMRI) of visual cortex in patients with ischemic infarction in the occipital lobe. Materials and Methods : Four patients with the symptoms and signs of visual cortical ischemia were included. Functional MRI was performed by 2D-FLASH technique with the parameter of 90/56msec TR/TE, $40^{\circ}$ flip angle, $240{\times}240{\;}FOV,{\;}64{\times}128$ matrix number, 8.32 seconds acquisition time, 8mm slice thickness. An axial slice including both visual cortices was selected and alternative activation and resting of the visual cortex was performed using red color photostimulator. all patients undertook visual field test, and vascular abnormality was examined by MRA (n=4) and DSA (n=2). fMRI results were compared with the results of a visual field test, conventional MRI and cerebral angiography. Results : On fMRI, decreased activity of the visual cortex was found in the occipital lobe corresponding to stenosis of the posterior cerebral artery or its branch noted on angiogram. However, 2 of 4 patients showed no abnormal findings on conventional MRI. Visual field defect was noted in 3 patients, one and of whom showed no abnormality on conventional MRI and diffusion-weighted image, but revealed decreased activity in the corresponding visual cortex on fMRI. Conclusion : fMRI may be a sensitive method for detection of the status of decreased blood flow or vascular reserve which other methods can not.

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