OBEZ ÇOCUKLARDA BEYNİN DİFÜZYON AĞIRLIKLI MANYETİK REZONANS GÖRÜNTÜLEME BULGULARI

Amaç: Bu çalışmada obez çocuklarda beynin açlıkve tokluk merkezlerindeki difüzyon ağırlıklımanyetik rezonans görüntüleme (DA-MRG)bulgularını ortaya koymayı amaçladık.Gereç ve Yöntemler: Çalışmaya 41 obez, 19 fazlakilolu (over weight =ow) ve 31 normal kilolu olan4-16 yaş arasındaki toplam 91 olgu alındı. Buolgularda DA-MRG ile b100, b600, b1000 veb2000 gradient değerlerinde difüzyon ağırlıklı ekoplanargörüntüler (EPI) alınıp, her olguda her bdeğeri için beyinde açlık ve toklukla ilişkili olanhipotalamus, hipokampal girus, orta temporalkorteks, insula, korpus striatum, singulat girus,orbitofrontal korteks, talamus, orta beyin, amigdala,oksipital korteks, dorsomedial frontal korteks,dorsolateral frontal korteks ve serebellum olmaküzere toplam 14 bölge belirlendi. Normal, fazlakilolu ve obez grubun b600, b1000 ve b2000değerlerinde görünür difüzyon katsayı (ApparentDiffusion Coefficient=ADC) haritaları üzerindenbelirlenen 14 bölgeden ölçüm yapıldı.Bulgular: Çalışmamızda; normal ve obez grubun,normal ve fazla kilolu grubun ve fazla kilolu veobez grubun b600, b1000 ve b2000 değerlerininkarşılaştırmasında; ADC değerlerinde istatikselolarak anlamlı fark bulunmuştur (p<0,05). Ayrıcabeden kitle indeksi (BKİ) artışıyla b600, b1000 veb2000 değerleri ile ADC değerleri arasında pozitifkorelasyon bulunmuştur.Sonuç: Sonuç olarak radyasyon verilmemesi, çokhızlı ve kolay elde edilebilmesi, kontrast maddeyegerek duyulmaması ile obez çocuklardaetyopatogenezde ve tanıda klinik ve laboratuarbulgularının yanında beynin DA-MRG bulgularınınfaydalı olabileceği kanaatindeyiz. Obezitede beyindokusundaki bu değişikliklerin anlaşılması ileobezite etyolojisinde altta yatan mekanizmanındaha iyi anlaşılmasına katkı sağlanabilir.

Diffusion weighted magnetic resonance imaging findings of the brain in obese children

Aim: To evaluate Diffusion Weighted Magnetic Resonance Imaging (DW MRI) findings in hunger and satiety related centers of the Brain in Obese Children. Material and Methods: 91 participants were enrolled in the study and 41 of them diagnosed as obese, 19 of them as overweight and 31 of them as non-obese volunteers and ages were ranged between 4-16. Diffusion weighted echo-plantar images of these cases taken in b100, b600, b1000 and b2000 gradient values and for each case b values determined for 14 regions of brain which are related with hunger and satiety. These regions are hypothalamus, hippocampal gyrus, middle temporal cortex, insula, corpus striatum, cingulate gyrus, orbitofrontal cortex, thalamus, midbrain, amygdala, occipital cortex, dorsomedial frontal cortex, dorsolateral frontal cortex and cerebellum. Measurements made with b600, b1000 and b2000values on 14 regions determined on Apparent Diffusion Coefficient (ADC) map for each group. Results: In ours study we have found a statistically significant difference between control and obese group,control and overweighed group and overweighed and obese group in ADC values in comparison of b600, b1000 and b2000 (p<0,05). Additionally we have found a positive correlation between body mass index and ADC values. Conclusion: We believe that, beside clinical and laboratory findings of obesity as a functional imaging modality use of DA-MRG which gives no radiation to body, obtaining fastly and require no contrast agent will provide usefull information about etiopathogenesis of obesity. To illuminate changes in brain tissue in obesity can provide more clear infotmation about ethology of obesity

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