Evaluation between 3.0 T vs 1.5 T MRI in Detection of Brain Metastasis using Double Dose Gd-DTPA

뇌전이 종양의 발견에 있어서 Doble dose Gd-DTPA를 이용한 3 T MRI와 1.5 T MRI간의 비교연구

  • Chung, Woo-Suk (Department of Diagnostic Radiology and Research Institute of Radiological Science, Yonsei University, College of Medicine, Yong Dong Severance Hospital) ;
  • Kim, Hyung-Jung (Pulmonary Division, Department of Internal Medicine, Yonsei University, College of Medicine, Yong Dong Severance Hospital) ;
  • Ahn, Chul-Min (Pulmonary Division, Department of Internal Medicine, Yonsei University, College of Medicine, Yong Dong Severance Hospital) ;
  • Lee, Jae-Hoon (Department of Diagnostic Radiology and Research Institute of Radiological Science, Yonsei University, College of Medicine, Yong Dong Severance Hospital) ;
  • Hur, Jin (Department of Diagnostic Radiology and Research Institute of Radiological Science, Yonsei University, College of Medicine, Yong Dong Severance Hospital) ;
  • Cho, Eung-Hyuck (Department of Diagnostic Radiology and Research Institute of Radiological Science, Yonsei University, College of Medicine, Yong Dong Severance Hospital) ;
  • Chung, Tae-Sub (Department of Diagnostic Radiology and Research Institute of Radiological Science, Yonsei University, College of Medicine, Yong Dong Severance Hospital)
  • 정우석 (연세대학교 영동세브란스병원 영상의학과) ;
  • 김형중 (연세대학교 영동세브란스병원 호흡기내과) ;
  • 안철민 (연세대학교 영동세브란스병원 호흡기내과) ;
  • 이재훈 (연세대학교 영동세브란스병원 영상의학과) ;
  • 허진 (연세대학교 영동세브란스병원 영상의학과) ;
  • 조응혁 (연세대학교 영동세브란스병원 영상의학과) ;
  • 정태섭 (연세대학교 영동세브란스병원 영상의학과)
  • Published : 2005.12.01

Abstract

Purpose : Early detection of small brain metastases is important. The purpose of this study was to compare the detectability of brain metastases according to the size between 1.5 T and 3.0 T MRI. Materials and Methods : We reviewed 162 patients with primary lung cancer who were examined for TNM staging. After administration of double dose of Gd-DTPA, MR imaging was performed with SPGR by 3.0 T MRI and then with T1 SE sequence by 1.5 T MRI. In each patient, three readers performed qualitative assessment. Sensitivity, positive predictive value, and diagnostic accuracy were calculated in 3.0 T and 1.5 T MRI according to size. Using the signal intensity (SI) measurements between the metastatic nodules and adjacent tissue, nodule-to-adjacent tissue SI ratio was calculated. Results : Thirty-one of 162 patients had apparent metastatic nodules in the brain at either 1.5 T or 3.0 T MR imaging. 143 nodules were detected in 3.0 T MRI, whereas 137 nodules were detected at 1.5 T MRI. Six nodules, only detected in 3.0 T MRI, were smaller than 3.0 mm in dimension. Sensitivity, positive predictive value, and diagnostic accuracy in 3.0 T MRI were 100 %, 100 %, and 100 % respectively, and in 1.5 T MRI were 95.8%, 88.3%, and 85.1% respectively. SI ratio was significantly higher in the 3.0 T MRI than 1.5 T MRI (p=0.025). Conclusion : True positive rate of 3.0 T MRI with Gd-DTPA was superior to 1.5 T MRI with Gd-DTPA in detection of metastatic nodules smaller than 3.0 mm.