Serebral Beyaz Cevherde Diffüzyon Değişiklikleri: Yaş ve Cinsiyetin Etkisi

Amaç: Myelinasyon, doğumdan sonra devam eden dinamik bir süreçtir. MR görüntüleme tekniklerinden biri olan difüzyon ağırlıklı görüntüleme (DAG) ve görünen difüzyon katsayısının (GDK) ölçümü, normal beyin gelişimi için bir kılavuzdur. Bu çalışmanın amacı çocuklarda normal miyelinasyon gelişiminin izlenmesinde DAG ve GDK haritalarının rolünü göstermek ve korpus kallozum (KK) ve temporal bölgelerde (TB) GDK değerlerini belirlemektir. Gereç ve Yöntem: MR görüntülerinin yeniden değerlendirildiği retrospektif çalışmaya 57'si erkek toplam 112 çocuk (ortalama yaş 98 ± 52,9 ay) dahil edildi. Katılımcılar 0 ile 202 ay arasında dört yaş grubuna ayrıldı. DAG ve GDK haritaları her iki TB'de KK'nın her iki tarafından ve parahipokampal sulkus beyaz cevherinden elde edildi. GDK değerlerinin ortalamaları belirlendi. Bulgular: Yaş ilerledikçe GDK değerlerinin tüm ölçüm alanlarında düştüğü görüldü (p< 0,005). Bu değişiklik TB'nin her iki tarafında ve KK genu ve gövdenin sol yarısında önemliydi. ADC değeri cinsiyete ve ölçülen tarafa göre değişmedi. Sonuç: GDK değerleri yaş ilerledikçe azalmaktadır. KK ve TB'nin ADC değerleri kullanılarak beyinde normal myelinasyon gelişimi ve ergenliğin neden olduğu değişiklikler diğer patolojilerden ayırt edilebilir.

Anahtar Kelimeler:

Görünür Difüzyon Katsayısı, Korpus Kallosum, Puberte, Temporal lob

Diffusion Changes in Cerebral White Matter: The Effect of Age and Gender

Objective: Myelination is a dynamic process that continues after birth. One of the MR imaging techniques diffusion-weighted imaging (DWI) and measurement of apparent diffusion coefficient (ADC) is a guide for normal brain development. The aim of this study is to show the role of DWI and ADC maps in monitoring the normal development of myelination in children, and to determine ADC values in corpus callosum (CC) and temporal regions (TL). Material and Method: A total of 112 children (mean age 98 ±52.9 months), 57 of whom were male, were included in the retrospective study in which MRI images were reevaluated. Participants were divided into four age groups between 0 and 202 months. DWI and ADC maps were obtained from both sides of CC and parahippocampal sulcus white matter in both TL. Averages of ADC values were determined. Results: It was found that ADC values decreased in all measurement areas as the age progressed (p< 0.005). This change was significant on both sides of the TL and left half of the CC genu and body. ADC value did not change according to gender and measured side. Conclusion: ADC values decrease with progressive increase of age. Using ADC values of CC and TL, the development of normal myelination in the brain and changes caused by puberty can be distinguished from other pathologies.

Keywords:

Apparent Diffusion Coefficient, Corpus Callosum, Puberty, Temporal lobe,

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