Anıl ÖZGÜR, Kaan ESEN, F. Demir APAYDIN, Engin KARA, Sema ERDEN, Sevgül KARA KÖSE

The Value of Diffusion Weighted Magnetic Resonance Imaging in Differentiation of Benign and Malignant Adrenal Lesions

Amaç: Difüzyon ağırlıklı görüntüleme (DAG) vücuttaki su moleküllerinin rastgele hareketlerini inceleyen bir fonksiyonel manyetik rezonans görüntüleme (MRG) tekniğidir. DAG intrakranial bozuklukların değerlendirilmesinde yaygın bir şekilde kullanılmasına rağmen, abdominal kitlelerin tespiti ve karakterizasyonunda kullanılmasına artan bir ilgi vardır. Bu çalışmada DAG'nin benign adrenal lezyonları malign olanlardan ayrımındaki yeterliliği araştırılmıştır. Materyal ve Metod: Elli altı hastadaki 66 fokal adrenal lezyon çalışmaya dahil edildi. Histopatolojik sonucu veya radyolojik takibi olmayan lezyonlar dinamik adrenal bilgisayarlı tomografi ve/veya adrenal MRG ile karakterize edildi. Bu lezyonlar için DAG yapıldı ve üç farklı b değeri kullanılarak (b=500 s/mm2, b=750 s/mm2, b=1000 s/mm) apparent diffusion coefficient (ADC) değerleri ölçüldü. Sonuçlar: Otuz dokuz benign lezyonun ortalama ADC değerleri b=500 s/mm için 1.54 x 10-3 mm/s , b=750 s/mm2için 1.01x 10-3 mm2/s ve b=1000 s/mm2 için 0.77 x 10-3 mm2/s ölçüldü. Yirmi yedi malign lezyonun ortalama ADC değerleri b=500 s/mm2, b=750 s/mm2 ve b=1000 s/mm2 için sırasıyla 1.69x 10-3 mm2/s, 1.14 x 10-3 mm2/s ve 0.86 x 10mm2/s olarak tespit edildi. Her üç b değeri için benign ve malign lezyonların ADC değerleri arasında istatistiksel olarak anlamlı fark yoktu(p < 0.05). Tartışma: Bu çalışmaya göre DAG benign ve malign adrenal lezyonların ayrımı için etkili bir yöntem olarak bulunmamıştır fakat daha doğru bir karar için gelişmiş ve yüksek çözünürlüklü görüntüler, standart teknik parametreler ve daha fazla sayıda lezyona ihtiyaç duyulabilir.

Difüzyon Ağırlıklı Manyetik Rezonans Görüntülemenin Benign ve Malign Adrenal Lezyonları Ayırt Etmedeki Değeri

Purpose: Diffusion weighted imaging (DWI) is a functional magnetic resonance imaging (MRI) technique that explores the random motion of water molecules in the body. Although DWI has been widely applied in the evaluation of intracranial disorders, there is growing interest for its use in detection and characterization of abdominal masses. In this study, the efficiency of DWI in distinguishing benign adrenal focal lesions from malignant ones is investigated. Material and Methods: Sixty six adrenal focal lesions in 56 patients were included in the study. The lesions were characterized with dynamic adrenal computed tomography and/or adrenal MRI if there was not a histopathological result or radiological follow up. DWI was performed for these lesions and apparent diffusion coefficient (ADC) values were measured by using three different b values (b=500 sec/mm2, b=750 sec/mm2, b=1000 sec/mm2). Results: The mean ADC values of 39 benign lesions were 1.54 x 10-3 mm2/sec for b=500 sec/mm2, 1.01x 10-3 mm2/sec for b=750 sec/mm2 and 0.77 x 10-3 mm2/sec for b=1000 sec/mm2. The mean ADC values of 27 malignant lesions were found to be 1.69x 10-3 mm2/sec, 1.14 x 10-3 mm2/sec and 0.86 x 10-3 mm2/sec for b=500 sec/mm2, b=750 sec/mm2, b=1000 sec/mm2, respectively. There was not any statistically significant difference between ADC values of benign and malignant lesions for all three b values (p < 0.05). Conclusion: According to this study, DWI did not seem to be an effective radiological method for differentiating benign and malignant adrenal lesions; but for a more accurate decision, studies with improved and high resolution images, standard technical parameters and larger number of lesions may be needed.

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