Voxel-based Morphometry (VBM) Based Assessment of Gray Matter Loss in Medial Temporal Lobe Epilepsy: Comparison with FDG PET

화소기반 형태분석 방법을 이용한 내측측두엽 간질환자의 회백질 부피/농도 감소평가; FDG PET과의 비교

  • Kang, Hye-Jin (Departments of Nuclear Medicine, Seoul National University) ;
  • Lee, Ho-Young (Departments of Nuclear Medicine, Seoul National University) ;
  • Lee, Jae-Sung (Departments of Nuclear Medicine, Seoul National University) ;
  • Kang, Eun-Joo (Departments of Nuclear Medicine, Seoul National University) ;
  • Lee, Sang-Gun (Departments of Neurology, Seoul National University) ;
  • Chang, Kee-Hyun (Departments of Diagnostic Radiology, Seoul National University) ;
  • Lee, Dong-Soo (Departments of Nuclear Medicine, Seoul National University)
  • 강혜진 (서울대학교 의과대학 핵의학교실) ;
  • 이호영 (서울대학교 의과대학 핵의학교실) ;
  • 이재성 (서울대학교 의과대학 핵의학교실) ;
  • 강은주 (서울대학교 의과대학 핵의학교실) ;
  • 이상건 (서울대학교 의과대학 신경과) ;
  • 장기현 (서울대학교 의과대학 방사선과학교실) ;
  • 이동수 (서울대학교 의과대학 핵의학교실)
  • Published : 2004.02.28

Abstract

Purpose: The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron omission tomography (FDG PET). Materials and Methods: MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was peformed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. Results: Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. Conclusions: Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones.

목적: 본 연구의 목적은 첫째, 내측 측두엽 간질환자의 MR 영상에 화소기반 형태분석방법(VBM)을 적용하여 회백질 부피감소를 보이는 영역을 뇌 전체를 관찰하여 찾아내고자 하였다. 둘째, 본 연구에서 적용된 VBM방법이 내측측두엽 간질환자의 간질병소의 편측성을 평가하기에 쓰일 수 있을지 조사하였다. MR영상으로 VBM 결과를 FDG PET의 SPM 분석결과와 비교하였다. 대상 및 방법: 12명의 좌측 내측측두엽 간질환자와 11명의 우측 내측측두엽 간질환자의 T1 강조영상을 각각 37명의 정상 대조군의 영상과 비교하였다. 모든 영상을 표준 뇌 표준판에 공간정합한 후, 평균영상을 생성하여 연구-특정적 뇌 표준판을 만들고 이 연구 측정적 표준판에 다시 비선형 공간정규화 하였다. 영상을 분할하여 회백질영상을 추출하고 변조한 후 편평화하였다. 환자군과 정상군의 차이를 SPM99를 이용하여 허위발견률을 기준으로 통계처리하였다. FDG PET 영상을 SPM을 이용하여 정상대조군 22명과 비교하였다. 결과: 좌측 내측측두엽 간질환자는 좌측의 해마와 편도체 영역에 회백질 부피/농도가 감소하였고, 뇌의 양측 소뇌, 전대상회, 방추상회의 부피/농도가 감소하였다. 우측 내측측두엽 간질환자는 우측 해마의 서 회백질이 감소하였다. 좌측 내측측두엽 간질은 좌측 측두엽과 시상 우측 내측측두엽간질 환자는 우측측두엽에 광범위한 부위에 FDG 섭취가 감소하였다. 결론: VBM 방법을 적용한 결과 간질원인 병소 해마와 해마주변영역에서 유의하게 회백질 부피/농도가 감소하였다. FDG PET SPM 분석에서 간질원인병소의 대사 감소를 찾을 수 있었던 것처럼, 이 연구에서 적용한 변조 VBM 방법은 내측측두엽 간질환자의 간질원인병소를 편측화할 수 있었고 내측측두엽을 제외한 다른 뇌영역의 해부학적 변화를 발견하는데 도움이 되었다. 이에 비하여 간질원인병소인 좌우측측두엽의 넓은 부위에 FDG 섭취가 감소하여 대조되었다.

Keywords

References

  1. Cheon JE, Chang KH, Kim HD, Han MH, Hong SH, Seong SO, et al. MR of hippocampal sclerosis: comparison of qualitative and quantitative assessments. AJNR Am J Neuroradiol. 1998:19:465-8
  2. Ashburner J, Friston KJ. Voxel-based morphometry--the methods. Neuroimage. 2000:11:805-21
  3. Ashburner J, Friston KJ. Why voxel-based morphometry should be used. Neuroimage. 2001:14:1238-43
  4. Salmond CH, Ashburner J, Vargha-Khadem F, Connelly A, Gadian DG, Friston K. Distributional assumptions in voxel-based morphometry. Neuroimage. 2002:17:1027-30
  5. Good CD, Johnsrude IS, Ashburner J, Henson RN, Friston KJ, Frackowiak RS. A voxel-based morphometric study of ageing in 465 normal adult human brains. Neuroimage. 2001:14:21-36
  6. Karas GB, Burton EJ, Rombouts SA, van Schijndel RA, O'Brien JT, Scheltens P, et al. A comprehensive study of gray matter loss in patients with Alzheimer's disease using optimized voxel-based morphometry. Neuroimage. 2003:18:895-907
  7. Busatto GF, Garrido GE, Almeida OP, Castro CC, Camargo CH, Cid CG, et al. A voxel-based morphometry study of temporal lobe gray matter reductions in Alzheimer's disease. Neurobiol Aging. 2003:24:221-31
  8. Baron JC, Chetelat G, Desgranges B, Perchey G, Landeau B, de la Sayette V, et al. In vivo mapping of gray matter loss with voxel-based morphometry in mild Alzheimer's disease. Neuroimage 2001:14:298-309
  9. Job DE, Whalley HC, McConnell S, Glabus M, Johnstone EC, Lawrie SM. Structural gray matter differences between first-episode schizophrenics and normal controls using voxel-based morphometry. Neuroimage. 2002:17:880-9
  10. Massana G, Serra-Grabulosa JM, Salgado-Pineda P, Gasto C, Junque C, Massana J, et al. Parahippocampal gray matter density in panic disorder: a voxel-based morphometric study. Am J Psychiatry 2003:160:566-8
  11. Keller SS, Mackay CE, Barrick TR, Wieshmann UC, Howard MA, Roberts N. Voxel-based morphometric comparison of hippocampal and extrahippocampal abnormalities in patients with left and right hippocampal atrophy. Neuroimage. 2002:16:23-31
  12. Won HJ, Chang KH, Cheon JE, Kim HD, Lee DS, Han MH, Kim IO, Lee SK, Chung CK. Comparison of MR imaging with PET and ictal SPECT in 118 patients with intractable epilepsy. AJNR Am J Neuroradiol. 1999;20:593-599
  13. Park SW, Chang KH, Kim HD, Song IC, Lee DS, Lee SK, Chung CK, Yu IK, Han MH, Park YH. Lateralizing ability of single-voxel proton mr spectroscopy in hippocampal sclerosis: comparison with mr imaging and positron emission tomography. AJNR Am J Neuroradiol. 2001;22:625-631
  14. Lee BI. Overview of epilepsy surgery. J Korean Med Sci. 1992;7:91-109
  15. Kim YK, Lee DS, Lee SK, Kim SK, Chung CK, Chang KH, Choi KY, Chung JK, Lee MC. Differential features of metabolic abnormalities between medial and lateral temporal lobe epilepsy: quantitative analysis of 18F-FDG PET using SPM. J Nucl Med. 2003;44:1006-1012
  16. Bookstein FL. "Voxel-based morphometry" should not be used with imperfectly registered images. Neuroimage 2001:14:1454-62
  17. Genovese CR, Lazar NA, Nichols T. Thresholding of statistical maps in functional neuroimaging using the false discovery rate. Neuroimage. 2002;15:870-8
  18. Keller SS, Wieshmann UC, Mackay CE, Denby CE, Webb J, Roberts N. Voxel based morphometry of grey matter abnormalities in patients with medically intractable temporal lobe epilepsy: effects of side of seizure onset and epilepsy duration. J Neurol Neurosurg Psychiatry 2002:73:648-55
  19. Bernasconi N, Bernasconi A, Caramanos Z, Antel SB, Andermann F, Arnold DL. Mesial temporal damage in temporal lobe epilepsy: a volumetric MRI study of the hippocampus, amygdala and parahippocampal region. Brain 2003:126:462-9
  20. Good CD, Johnsrude I, Ashburner J, Henson RN, Friston KJ, Frackowiak RS. Cerebral asymmetry and the effects of sex and handedness on brain structure: a voxel-based morphometric analysis of 465 normal adult human brains. Neuroimage 2001:14:685-700
  21. Thompson PM, Mega MS, Woods RP, Zoumalan CI, Lindshield CJ, Blanton RE, et al. Cortical change in Alzheimer's disease detected with a disease-specific population-based brain atlas. Cereb Cortex 2001:11:1-16
  22. Kim JJ, Lee MC, Kim J, Kim IY, Kim SI, Han MH, et al. Grey matter abnormalities in obsessive-compulsive disorder: statistical parametric mapping of segmented magnetic resonance images. Br J Psychiatry. 2001; 179:330-334 https://doi.org/10.1192/bjp.179.4.330