• Title/Summary/Keyword: MR spectroscopy

Search Result 138, Processing Time 0.028 seconds

Arterial Spin Labelling Perfusion, Proton MR Spectroscopy and Susceptibility-Weighted MR Findings of Acute Necrotizing Encephalopathy: a Case Report

  • Kwon, Hwanwoong;Choi, Dae Seob;Jang, Jungho
    • Investigative Magnetic Resonance Imaging
    • /
    • v.23 no.2
    • /
    • pp.157-161
    • /
    • 2019
  • In this study, we report arterial spin labelling perfusion, proton MR spectroscopy and susceptibility-weighted MR findings of acute necrotizing encephalopathy in a child with rotavirus infection.

In-vivo $^1H$ MR Spectroscopy in Abscessess Induced in Rabbit Thighs: Evaluation of Treatment Effect (토끼 대퇴부에 유발한 농양의 생체내 수소 자기공명분광법: 치료효과 평가)

  • 구진모;장기현;이경호;한문희;송인찬
    • Investigative Magnetic Resonance Imaging
    • /
    • v.7 no.1
    • /
    • pp.31-38
    • /
    • 2003
  • Purpose : To analyze the serial changes of proton magnetic resonance (MR) spectra in the abscess and to determine the effect of the antibiotic treatment on the metabolite patterns. Materials and Methods : MR imaging and MR spectroscopy of an experimentally induced abscess were performed sequentially for four weeks at interval of one week in both the control group (n=5) and the antibiotic treatment group (n=5). On MR imaging, the shape and the size of the abscess were analyzed. On MR spectroscopy, the resonance peaks of metabolites were assigned on the basis of reported peaks in the literature. The metabolite ratios measured by using N-acetyl alanine as an external reference and by using lipid as an internal reference were compared in both the control and treatment g roups. Results : The abscesses were seen as cystic masses on MR imaging. On MR spectroscopy, the variable peaks of acetate, succinate and various amino acids, which are the metabolites of infection, were identified in the control and antibiotic treatment groups. The most frequent peak was that of acetate at 1.92ppm (70%). Both the peak ratios of acetate to lipid and acetate to external reference tended to decrease in the treatment group while the ratios did not change significantly in the control group. Conclusion : MR spectroscopy is useful not only for the diagnosis of abscess but also for monitoring the evolution of the abscess by using the acetate peak.

  • PDF

MR Spectroscopy and Diffusion Weighted Imaging Findings of Primary Non-Hodgkin Lymphoma of the Breast: Two Case Reports (유방에 발생한 일차성 비호지킨림프종의 자기공명 분광법 및 확산강조 영상: 2예)

  • Nam, Sang Yu;Yoo, Eun Young;Choi, Hye-Young
    • Investigative Magnetic Resonance Imaging
    • /
    • v.18 no.2
    • /
    • pp.176-181
    • /
    • 2014
  • Primary non-Hodgkin lymphoma (NHL) of the breast is a very rare disease, and the mammographic and ultrasonographic findings of breast lymphoma are variable. There are several reports of magnetic resonance (MR) imaging findings in patients with breast lymphomas; however, few reports have described the findings observed on MR spectroscopy or the features of diffusion weighted (DW) imaging. The authors report the findings of classical MR imaging, MR spectroscopy and DW imaging of a 48-year-old woman and a 40-year-old woman with primary non-Hodgkin's lymphoma of breasts. Mammography and breast ultrasonography revealed a mass with circumscribed margin. The mass showed strong enhancement after contrast injection on MR imaging. DW imaging showed reduced diffusion and high-amplitude choline (Cho) peak at 3.22 ppm was detected by single voxel MR spectroscopy which was consistent with malignancy.

Endovaginal and Endorectal Surface Coils for in-ViVo Human MR Imaging and Spectroscopy (자궁경부암 진단용 MR 질내표면코일과 전립선암 진단용 MR 경직장표면코일의 제작 : 인체에서의 MR 영상과 MR 분광)

  • 문치웅;조경식
    • Journal of Biomedical Engineering Research
    • /
    • v.16 no.4
    • /
    • pp.481-491
    • /
    • 1995
  • Endovaginal and endorectal receiver only surface coils were designed for MR imaging (MRI) and $^1H$ MR spectroscopy (MRS) for the uterine cervix and the prostate. The shape of endovaginal coil wire was rectangular with round corner. Size of the coil wire was empirically determined for 7cm and 4cm along the long and short axis, respectively. The coil wire loop was supported by acryl handle and bent about $150^{\circ}$ at one side of the loop considering the average angle of the cervix to the vagina. We called this as a "spoon-type endovaginal coil". The wire of the endorectal coil was made of the flexible materials so that the wire loop became long elliptic shape by pushing the acryl handle into the plastic tube for the comfort of patients when the coil was inserted into the cervix. Then, the shape was maintained to be circle by popping out handle. Conventional spin echo (SE) and fast spin echo (FSE) sequences were used as 71 and 72 weighted imaging sequences, respectively. Matrix size was 128~$256{\times}256$. FOVs for surface coil and body coil were 14cm and 24cm, respectively. 3D volume localized in vivo $^1H$ MR spectroscopy of the human cervix and prostate was performed using PRESS or STEAM localization method with the following parameters . TR=3 sec, TE=135 msec for PRESS or 30 msec for STEAM, NEX=2, NS=48, Sl=2048, and SW=2500 Hz. Using home-built endovaginal and endorectal coils, excellent T1- and T2-images were obtained to visualize early cervical and prostate tumors. 3D volume localized in vivo IH MRS was useful to differentiate the cancerous tissue from the normal tissue.

  • PDF

Comparison of in Vivo, in Vitro 3T MR Spectroscopy and Proton NMR Spectroscopy for the Fluid from Cystic Tumor: Preliminary Study (낭성 종양의 체액에 대한 생체내, 생체외 3T 양성자 자기공명분 광법과 양성자 핵자기공명기법의 비교: Preliminary Study)

  • Lee, Hui-Joong;Kim, Jong-Yeol;Chang, Yong-Min
    • Investigative Magnetic Resonance Imaging
    • /
    • v.12 no.2
    • /
    • pp.107-114
    • /
    • 2008
  • Purpose : The aim of this study is to determine possibility of application of in vivo proton ($^1H$) magnetic resonance spectroscopy (MRS) in distinguishing cystic mass arising around pancreas by comparison of in vivo MRS, in vitro MRS using 3T MR machine, based on nuclear magnetic resonance (NMR). Materials and Methods : We obtained spectra of in vivo MRS, in vitro MRS and NMR from abdominal mass arising around pancreas (mucinous cystic neoplasm=5, intraductal papillary mucin producing tumor=5, pseudocyst=1, and lymphangioma=1). We estimated existence of peak of in vivo MRS, and in vitro MRS concordant to that of NMR. We also evaluated differential peak for predicting specific disease. Results : Correlation of presence of peak with NMR showed showed sensitivity of 29.6%, specificity of 82.6% and accuracy of 67.7% on in vivo MRS (p = 0.096, McNemar test), sensitivity of 57.1% and specificity of 92.6% and accuracy of 82.3% on in vitro MRS (p = 0.362, McNemar test). The spectra of NMR for IPMT showed more frequent peaks at 3.5-4.0 ppm (p=0.026). Conclusion : Although chemical analysis, using NMR could be regarded as possible tool to differentiate cystic masses, in vivo and in vitro MRS need further technical evolution for clinical application.

  • PDF

Development of PC Based Signal Postprocessing System in MR Spectroscopy: Normal Brain Spectrum in 1.5T MR Spectroscopy (PC를 이용한 자기공명분광 신호처리분석 시스템 개발: 1.5T MR Spectroscopy에서의 정상인 뇌 분광 신호)

  • 백문영;강원석;이현용;신운재;은충기
    • Investigative Magnetic Resonance Imaging
    • /
    • v.4 no.2
    • /
    • pp.128-135
    • /
    • 2000
  • Purpose : The aim of this study is to develope the Magnetic Resonance Spectroscopy(MRS) data processing S/W which plays an important role as a diagnostic tool in clinical field. Materials and methods : Post-processing software of MRS based on graphical user interface(GUI) under windows operating system of personal computer(PC) was developed using MATLAB(Mathwork, U.S.A.). This tool contains many functions to increase the quality of spectrum data such as DC correction, zero filling, line broadening, Gauss-Lorentzian filtering, phase correction, etc. And we obtained the normal human brain $^1H$ MRS data from parietal white matter, basal ganglia and occipital grey matter region using 1.5T Gyroscan ACS-NT R6 (philips, Amsterdam, Netherland) MRS package. The analysis of the MRS peaks were performed by obtaining the ratio of peak area. Results : The peak ratios of NAA/Cr, Cho/Cr, MI/Cr for the different MRS machines have a little different values. But these peak ratios were not significantly different between different echo time MRS peak ratios in the same machine (p<0.05). Conclusion : MRS post-processing S/W based on GUI using PC was developed and applied to the analysis of normal human brain $^1H$ MRS. This independent MRS processing job increases the performance and throughput of patient scan of main console. Finally, we suggest that the database for normal in-yivo human MRS data should be obtained before clinical applications.

  • PDF

MR Spectroscopy of Cerebral Fat Embolism in Cats

  • Park Byung-Rae
    • Biomedical Science Letters
    • /
    • v.11 no.2
    • /
    • pp.221-225
    • /
    • 2005
  • To investigate the spectroscopic findings of embolized lesions induced with a fat-emulsion technique with magnetic resonance images (MRI). A fat emulsion was made with 0.1 ml of triolein and 20 ml of normal saline. In 12 cats, the internal carotid artery was infused with the fat emulsion. Contrast-enhanced T1-weighted MRI and multivoxel spectroscopy were obtained at 1 hour, 1 and 4 days, and 1 week after embolization. NAA (N-acetylaspartate), Cr (creatine) and Cho (choline) were evaluated on the spectroscopy. Statitistical analysis wsperformed at the embolized and contralateral normal hemisphere in the integral and amplitude of NAA, Cr and Nho in time course. Also NAA/Cr and Cho/Cr were compared in both hemisphere and in time course. The emboli zed lesions showed contrast enhance ments on Gd-enhanced Tl-weighted i~ages at 1 hour. This contrast enhancement was decreased at day 1, and id not appear agter day 4. In spectroscopy, the embolized hemisphere showed no statistical difference to the normal contralateral side at 1 hour and in time course. NAA/Cr and Cho/Cr were not significantly different in both hemispheres at 1 hour and in time course. Cerebral-fat embolism induced by a triolein emulsion in cats revealed no statistical difference on MR spectroscopy. Triolein-emulsion can be used in the study of blood-brain barrier.

  • PDF

Characteristic findings of proton magnetic resonance spectroscopy of primary central nervous system Iymphoma

  • Kim, Seung-Hun;Lee, Hui-Joong;Kim, Yong-Sun
    • Proceedings of the KSMRM Conference
    • /
    • 2003.10a
    • /
    • pp.25-25
    • /
    • 2003
  • Purpose: In order to characterise primary central nervous system Iymphomas (PCNSL) and to evaluate if 1H spectroscopy improves the preoperative differential diagnosis of other diseases. Method: We reviewed 11 MR imaging and 7 MR spectroscopy of 9 patient with Iymphoma confirmed by stereotatic biopsy.

  • PDF

Polarization dependence on Cavity Ringdown Spectroscopy (공동 광자감쇠 분광학에서의 편광의존성)

  • 김재완;한재원
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2000.08a
    • /
    • pp.216-217
    • /
    • 2000
  • 상자성을 갖는 분자에 대한 분광학 연구에서는 제만(Zeeman) 효과로 생기는 이색성을 이용한 magnetic rotation spectroscopy (MRS)가 널리 사용되고 있다.$^{(1)}$ MRS가 일반적인 흡수 분광법에 비해 더 민감한 측정을 할 수 있기는 하지만 사용하는 편광기의 extinction ratio에 의해 감도가 한정된다. MRS의 감도를 높이는 방법으로는 광경로를 길게 만드는 것을 고려할 수 있다. 일반적으로 공진기 광자감쇠 분광학(Cavity Ring-Down Spectroscopy, CRDS)은$^{(2)}$ 높은 반사율을 갖는 거울을 사용해서 수 km 이상의 광 경로를 만들기 때문에 감도가 높다. (중략)

  • PDF

A Study on the Insertional Coil of MRI Device for Diagnosis (진단용 자기공명영상장치의 삽입 코일에 관한 연구)

  • Lee, Yong-Moon;Lim, Keun-Ho;Seo, Dae-Keon;Kim, Wang-Gon;Hong, Jin-Woong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2003.05d
    • /
    • pp.33-37
    • /
    • 2003
  • Endovaginal and endorectal receiver only surface coil were designed for MR imaging(MRI) and $^1H$ MR spectroscopy(MRS) for the uterine cervix and the prostate. The shape of endovaginal coil wire was rectangular with round comer. The shape of endorectal coil wire was long elliptic shape during insertion and circular shape after insertion. Conventional spin echo and fast spin echo sequences were used as T1 and T2 weighted imaging sequences, respectively. 3D volume localized in vivo $^1H$ MR spectroscopy of the human cervix and prostate was performed using PRESS or STEAM localization method. Using home-built endvaginal and endorectal coils, excellent T1 and T2 images were obtained to visualize early cervical and prostate tumors. 3D volume localized in vivo $^1H$ MRS was useful to differentiate the cancerous tissue from the normal tissue.

  • PDF