Serebral Beyaz Cevherde Diffüzyon Değişiklikleri: Yaş ve Cinsiyetin Etkisi

Yıl 2021, Cilt: 3 Sayı: 3, 63 - 70, 14.10.2021

Avni Merter Keçeli

Öz

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

Öz

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.

Anahtar Kelimeler

Apparent Diffusion Coefficient, Corpus Callosum, Puberty, Temporal lobe

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