3 Tesla MR Cihazında Beyin Diffüzyon Değerlerinde Hemisferik Farklılıklar

Abstract

Objectives: The purpose of this study is to demonstrate the variability of the diffusion values in different anatomical regions of the brain. Materials and Methods: 3T diffusion MR images of 190 patients underwent brain imaging were evaluated. Patients were divided into groups according to ages: 20-29, 30-39, 40-49, 50-59, 60-69. The ROIs were placed in the frontal, temporal, occipital, parietal lobes, cerebellum, thalamus, to be of equal size in both hemispheres. The ADC values obtained were standardized by dividing by the ADC values obtained from the ventricle. Results: One hundred and ninety patients, 97 men and 93 women, aged between 20 and 69 years, were included in the study.The mean ADC values were: frontal lobe=726,8x10-3 mm2/sec (532-945x10-3 mm2/sec), cerebellum=680x10-3 mm2/sec (586-816x10-3 mm2 /(609-996x10-3 mm2/sec) in the temporal lobe=791,2x10-3 mm2/sec (448-945x10-3 mm2/sec), parietal=789,9x10-3 mm2/sec (671-935 x10-3 mm2/sec) and in the occipital=790,6x10-3 mm2/sec (690-973x10-3 mm2/sec). Significant differences were found in the frontal, temporal lobes and cerebellum (p=0.600, p=0.430, p=0.227, respectively) in the thalamus, parietal and occipital lobes when the whole brain was evaluated. 0.011, p=0.000, p=0.000). There was a significant difference between all age groups for all lobes. When the frontal lobe, cerebellum, thalamus, temporal, parietal and occipital lobes were evaluated, the highest ADC values were obtained between ages 60-69 (748±44×10-3 mm2/sec, 689±34×10-3 mm2/sec, 731±41x10-3 mm2/sec, 827+41x10-3 mm2/sec, 809+56x10-3 mm2/sec, 821+56x10-3 mm2/sec). Conclusion: In different anatomical regions of brain, diffusion values are different.

Keywords

• Diffusion Magnetic Resonance
• Apparent Diffusion Coefficient
• Hemispheric Differences

References

1. 1. Helenius J, Soinne L, Perkiӓ J, Salonen O, Kangasmӓki A, Kaste M, Carano RAD, Aronen HJ, Tatlisumak T. Diffusion-Weighted MR Imaging in Normal Human Brains in Various Age Groups. AJNR. 2002;23:194-200.
2. 2. Shimony JS, McKinstry RC, Erbil A, et al. Quantitative diffusion-tensor anisotropy brain MR imaging: normative human data and anatomic analysis. Radiol. 1999;212:770-784.
3. 3. Naganawa S, Sato K, Katagiri T, et al. Regional ADC values of the normal brain: differences due to age, gender, and laterality. Eur Radiol. 2003;13:6-13.
4. 4. Fabiano AJ, Horsfield MA, Bakshi R. Interhemispheric Asymmetry of Brain Diffusivity in Normal Individuals: A Diffusion-Weighted MR Imaging Study. AJNR. Am J Neuroradiol. 2005;26:1089-1094.
5. 5. Harada K, Fujita N, Sakurai K, et al. Diffusion imaging of the human brain: a new pulse sequence application for a 1.5-T standard MR system. AJNR Am J Neuroradiol. 1991;12:1143–1148.
6. 6. Good CD, Johnsrude I, Ashburner J, et al. 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.
7. 7. Penhune VB, Zatorre RJ, MacDonald JD, et al. Interhemispheric anatomical differences in human primary auditory cortex: probabilistic mapping and volume measurement from magnetic resonance scans. Cereb Cortex. 1996;6:661-672.
8. 8. Szabo CA, Lancaster JL, Xiong J, et al. MR imaging volumetry of subcortical structures and cerebellar hemispheres in normal persons. AJNR Am J Neuroradiol. 2003;24:644-647.

9. 9. Willis MW, Ketter TA, Kimbrell TA, et al. Age, sex, and laterality effects on cerebral glucose metabolism in healthy adults. Psychiatry Res. 2002;114:23-37.
10. 10. Gideon P, Thomsen C, Henriksen O. Increased self-diffusion of brain water in normal aging. J Magn Reson Imaging. 1994;4:185-188.
11. 11. Nusbaum AO, Tang CY, Buchsbaum MS, et al. Regional and global changes in cerebral diffusion with normal aging. Am J Neuroradiol. 2001;22:136-142.
12. 12. Hosoda T, Nakajima H, Honjo H. Estrogen protects neuronal cells from amyloid beta-induced apoptotic cell death. Neuroreport. 2001;12:1965-1970.
13. 13. Savaskan E, Olivieri G, Meier F, et al. Hippocampal estrogen betareceptor immunoreactivity is increased in Alzheimer’s disease. Brain Res. 2001;908:113-119