KORPUS KALLOSUMUN DİFÜZYON AĞIRLIKLI VE KONVANSİYONEL MANYETİK REZONANS GÖRÜNTÜLEME İLE YAŞA GÖRE DEĞERLENDİRİLMESİ

Abstract

Amaç: Difüzyon ağırlıklı görüntüleme, beyin dokusunun canlılığı hakkında fikir veren önemli bir yöntem olup kuvvetli manyetik alan gradientleri kullanılmaktadır. Buna bağlı olarak difüzyon ağırlıklı görüntüleme tekniği su moleküllerinin mikroskopik hareketlerindeki değişikliklerin saptanmasını mümkün kılmaktadır. Çalışmamızda, difüzyon ağırlıklı görüntüleme ile su moleküllerinin aksonlar boyunca olan hareketlerinden yararlanarak elde edilen Apparent Diffusion Coefficient (ADC) değişikliklerinin yaşa göre değişiminin değerlendirilmesi amaçlanmıştır.

Gereç ve Yöntem: Çalışmamıza dahil edilen 94 olgunun ADC haritaları üzerinden korpus kallosumun farklı bölgelerinden ADC değerleri değerlendirildi.

Bulgular: ADC değerinin minimum ve maksimum değerleri 0.589-0.819 mm²/sn x 10^-³, ortalama ADC değeri ise 0.735 ± 0.043 mm²/sn x 10^-³ olarak bulunmuştur. Çalışmamızda yaş arttıkça, korpus kallosumun ortalama ADC değerlerinde istatistiksel olarak belirgin derecede artış bulunmuştur (p <0.01).

Sonuç: İlerleyen yaşla beyaz cevherdeki suyun difüzyon kabiliyetindeki artış yönündeki teorimiz, verilerimizdeki istatistiksel olarak anlamlı sonuçlarla desteklenmiştir. Yani suyun korpus kallosumda difüzyon kabiliyetinin yaş ilerledikçe arttığı saptanmıştır. Sonuç olarak, fonksiyonel bir görüntüleme yöntemi olan difüzyon ağırlıklı görüntüleme, yaşlanmaya bağlı değişiklikleri sayısal olarak da ortaya koyabilen bir yöntemdir.

Keywords

• korpus kallosum,Difüzyon ağırlıklı görüntüleme,Apparent Diffusion Coefficient,yaş

Evaluation of Corpus Callosum by Means of Diffusion-Weighted and Conventional Magnetic Resonance Imaging According to the Age

Abstract

Objective: Evaluation of corpus callosum by means of diffusion-weighted and conventional magnetic resonance imaging according to the age Diffusion-weighted imaging (DWI) is a significant method that gives an idea as to the vitality of the brain tissue. DWI is affected from the movements of the patient at a minimum with its strong magnetic field gradients and is extraordinarily sensitive in reflection of the changes in the microscopic translational activities of the water molecules. Objective of our study is to evaluate by means of diffusion-weighted imaging the Apparent Diffusion Coefficient (ADC) changes by aging which are obtained using the activities of the water molecules throughout axons.

Material and Methods: ADC measurement of corpus callosum at different parts has been studied in 94 patient

Results: Minimum and maximum values of the ADC value were found as 0.589-0.819 mm²/sn x 10^-³ while the average ADC value was found as 0.735 ± 0.043 mm²/sn x 10^-³. Our study has revealed a distinctive statistical increase in the average ADC values of corpus callosum in line with aging (p <0.01).

Conclusion: Our theory as to the increase in the diffusion capability of the water in the white substance along with aging has been substantiated with the statistically significant results in our data. In other words, it has been detected that diffusion capability of the water in corpus callosum increases along with aging. In conclusion, it is beyond doubt that the diffusion-weighted MRI which is a new functional imaging method in clinic application will be improved even better in the years to come and can be used in a more widespread manner.

Keywords

• Diffusion-weighted imaging,Apparent Diffusion Coefficient,corpus callosum,age

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