Elif PEKER, İlhan ERDEN, Ayşegül Gürsoy ÇORUH

3 Tesla MR Cihazında Beyin Diffüzyon Değerlerinde Hemisferik Farklılıklar

Amaç: Bu çalışmanın amacı, beynin farklı anatomik bölgelerindeki diffüzyon değerlerinin değişkenliğinin ortaya konmasıdır.Gereç ve Yöntem: 3 Tesla MR cihazında beyin görüntülemesi yapılan 190 hastanın diffüzyon MR görüntüleri değerlendirilmiştir. Hastalar 20-29, 30-39, 40-49, 50-59, 60-69 yaşları arasında gruplara ayrılmışlardır. ROIler frontal, temporal, oksipital, paryetal loblara, her iki serebellumave talamuslara her iki hemisferde eşit boyutta olacak şekilde yerleştirilmiştir. Elde edilen ADC değerleri ventrikülden elde edilen ADC değerlerinebölünerek standardize edilmiştir.Bulgular: Çalışmaya yaşları 20 ile 69 arasında değişen 97 erkek, 93 kadın olmak üzere, 190 hasta dahil edilmiştir.ADC değerlerinin ortalaması frontal lobda=726,8x10-3 mm2/sn (532-945x10-3 mm2/sn), serebellumda=680x10-3 mm2/sn (586-816x10-3 mm2/sn),talamusta=725,8x10-3 mm2/sn (609-996x10-3 mm2/sn), temporal lobda=791,2x10-3 mm2/sn (448-945x10-3 mm2/sn), paryetalde: 789,9x10-3 mm2/sn (671-935x10-3 mm2/sn), oksipitalde=790,6x10-3 mm2/sn (690-973 x10-3 mm2/sn) olarak bulunmuştur. Tüm beyin değerlendirildiğinde parankim/ventrikül ADC değerleri talamus, paryetal ve oksipital loblarda sağ ve sol lob arasında anlamlı fark izlenmezken (sırasıyla p=0,600, p=0,430, p=0,227),frontal, temporal loblarda ve serebellumda anlamlı fark saptanmıştır (sırasıyla p=0,011, p=0,000, p=0,000). Tüm loblar için yaş grupları arasındaanlamlı fark izlenmiştir. Frontal lob, serebellum, talamus, temporal, paryetal ve oksipital lob değerlendirildiğinde en yüksek ADC değerleri 60-69 yaşları arasında elde edilmiştir (748±44x10-3 mm2/sn, 689±34x10-3 mm2/sn, 731± 41x10-3 mm2/sn, 827±41x10-3 mm2/sn, 809±56x10-3 mm2/sn,821±56x10-3 mm2/sn).Sonuç: Beynin farklı anatomik bölgelerinde, aynı anatomik bölgede olsa da farklı yaş gruplarında diffüzyon değerleri değişmektedir.

Hemispheric Differences in Brain Diffusion Values in 3 Tesla MR

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.

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