Warntjes J B M, Tisell A, Landtblom A-M, Lundberg P
From the Center for Medical Image Science and Visualization, (J.B.M.W., A.T., P.L.)Clinical Physiology (J.B.M.W.)Departments of Clinical Physiology (J.B.M.W.)
From the Center for Medical Image Science and Visualization, (J.B.M.W., A.T., P.L.)Radiation Physics (A.T.), Department of Medical and Health Sciences, Faculty of Health Sciences, Linköping University, Linköping, Sweden.
AJNR Am J Neuroradiol. 2014 Jul;35(7):1330-6. doi: 10.3174/ajnr.A3890. Epub 2014 Apr 3.
The administration of gadolinium contrast agent is a common part of MR imaging examinations in patients with MS. The presence of gadolinium may affect the outcome of automated tissue classification. The purpose of this study was to investigate the effects of the presence of gadolinium on the automatic segmentation in patients with MS by using the synthetic tissue-mapping method.
A cohort of 20 patients with clinically definite multiple sclerosis were recruited, and the T1 and T2 relaxation times and proton density were simultaneously quantified before and after the administration of gadolinium. Synthetic tissue-mapping was used to measure white matter, gray matter, CSF, brain parenchymal, and intracranial volumes. For comparison, 20 matched controls were measured twice, without gadolinium.
No differences were observed for the control group between the 2 measurements. For the MS group, significant changes were observed pre- and post-gadolinium in intracranial volume (-13 mL, P < .005) and cerebrospinal fluid volume (-16 mL, P < .005) and the remaining, unclassified non-WM/GM/CSF tissue volume within the intracranial volume (+8 mL, P < .05). The changes in the patient group were much smaller than the differences, compared with the controls, which were -129 mL for WM volume, -22 mL for GM volume, +91 mL for CSF volume, 24 mL for the remaining, unclassified non-WM/GM/CSF tissue volume within the intracranial volume, and -126 mL for brain parenchymal volume. No significant differences were observed for linear regression values against age and Expanded Disability Status Scale.
The administration of gadolinium contrast agent had a significant effect on automatic brain-tissue classification in patients with MS by using synthetic tissue-mapping. The observed differences, however, were much smaller than the group differences between MS and controls.
钆对比剂的使用是多发性硬化症（MS）患者磁共振成像检查的常见环节。钆的存在可能会影响自动组织分类的结果。本研究的目的是通过使用合成组织映射方法，研究钆的存在对MS患者自动分割的影响。
招募了20例临床确诊的多发性硬化症患者，在注射钆前后同时对T1和T2弛豫时间以及质子密度进行定量。使用合成组织映射来测量白质、灰质、脑脊液、脑实质和颅内体积。为作比较，对20名匹配的对照组进行了两次测量，未使用钆。
对照组两次测量之间未观察到差异。对于MS组，注射钆前后颅内体积（-13 mL，P <.005）、脑脊液体积（-16 mL，P <.005）以及颅内体积内其余未分类的非白质/灰质/脑脊液组织体积（+8 mL，P <.05）有显著变化。与对照组相比，患者组的变化要小得多，对照组的白质体积差异为-129 mL，灰质体积差异为-22 mL，脑脊液体积差异为+91 mL，颅内体积内其余未分类的非白质/灰质/脑脊液组织体积差异为24 mL，脑实质体积差异为-126 mL。针对年龄和扩展残疾状态量表的线性回归值未观察到显著差异。
通过使用合成组织映射，钆对比剂的使用对MS患者的自动脑组织分类有显著影响。然而，观察到的差异远小于MS患者与对照组之间的组间差异。
