Behrouz Vejdani Afkham1, Sadegh Masjoodi1, Mohammad Ali Oghabian1, Seyed Roholah Ghodsi2, Mohammad Reza Nazem Zadeh3, Ebrahim Esmati4, Mostafa Farzin5, Maziar Gilasi6, Hasan Hashemi7,8. 1. Medical Physics and Biomedical Engineering, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. 2. Development Center of Tehran University of Medical Science, Tehran, Iran. 3. Research Center for Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran, Iran. 4. Radiation Oncology, Cancer Institute, Tehran University of Medical Science, Tehran, Iran. 5. Brain and Spinal Cord Injury Research Center, Neuroscience Institute, Tehran University of Medical Sciences, Tehran, Iran. 6. Medical Imaging Center, Imam Khomeini Hospital, Tehran, Iran. 7. Advanced Diagnostic and Interventional Radiology Research Center (ADIR), Tehran University of Medical Sciences, Tehran, Iran. Hashemi_mic@yahoo.com. 8. Department of Radiology, Imam Khomeini Hospital, Institute of Tehran University of Medical Sciences, Keshavarz Blvd, Tehran, 1417743855, Iran. Hashemi_mic@yahoo.com.
Abstract
OBJECTIVES: The goal of this study is to examine the effect of contrast agent (CA) dose and diffusion coefficient on the estimation of vessel size index (VSI). MATERIALS AND METHODS: Three groups of four participants were enrolled in this study and two different experiments were performed. Different dose of CA, namely 0.1 mmol/kg and 0.05 mmol/kg were assessed in two groups of normal subjects. Diffusion coefficient effect was assessed in the third group with high-grade glioma. Imaging included gradient echo and spin-echo DSC and DTI on a 3-T MR Scanner. RESULTS: VSI estimation using half of standard dose of CA showed higher values compared to the application of standard, with a ratio of 2 for the WM and 1.5 for the GM. VSI estimates for tumor tissues (22 µm) were considerably higher compared to contra-lateral Normal-Appearing WM (NAWM, 4 µm, P < 0.01) and Normal-Appearing GM (NAGM, 8 µm, P < 0.04). DISCUSSION: Application of standard dose for CA injection and also taking into account the effect of diffusion coefficient can lead to a better correlation of VSI with previous theoretically predicted values and improvement of individual diagnostics in tumor evaluations.
OBJECTIVES: The goal of this study is to examine the effect of contrast agent (CA) dose and diffusion coefficient on the estimation of vessel size index (VSI). MATERIALS AND METHODS: Three groups of four participants were enrolled in this study and two different experiments were performed. Different dose of CA, namely 0.1 mmol/kg and 0.05 mmol/kg were assessed in two groups of normal subjects. Diffusion coefficient effect was assessed in the third group with high-grade glioma. Imaging included gradient echo and spin-echo DSC and DTI on a 3-T MR Scanner. RESULTS: VSI estimation using half of standard dose of CA showed higher values compared to the application of standard, with a ratio of 2 for the WM and 1.5 for the GM. VSI estimates for tumor tissues (22 µm) were considerably higher compared to contra-lateral Normal-Appearing WM (NAWM, 4 µm, P < 0.01) and Normal-Appearing GM (NAGM, 8 µm, P < 0.04). DISCUSSION: Application of standard dose for CA injection and also taking into account the effect of diffusion coefficient can lead to a better correlation of VSI with previous theoretically predicted values and improvement of individual diagnostics in tumor evaluations.
Authors: I Troprès; S Grimault; A Vaeth; E Grillon; C Julien; J F Payen; L Lamalle; M Décorps Journal: Magn Reson Med Date: 2001-03 Impact factor: 4.668
Authors: Jussi Perkiö; Hannu J Aronen; Aki Kangasmäki; Yawu Liu; Jari Karonen; Sauli Savolainen; Leif Østergaard Journal: Magn Reson Med Date: 2002-05 Impact factor: 4.668
Authors: Kathleen M Schmainda; Scott D Rand; Allen M Joseph; Rebecca Lund; B Doug Ward; Arvind P Pathak; John L Ulmer; Michael A Badruddoja; Michael A Baddrudoja; Hendrikus G J Krouwer Journal: AJNR Am J Neuroradiol Date: 2004-10 Impact factor: 3.825