Dev Araknoid Granülasyonların 3T MR Görüntüleme Bulguları

Amaç: Bu çalışmada amacımız dev araknoid granülasyonların 3T MR görüntüleme özelliklerinin değerlendirilmesidir. Hastalar ve Yöntemler: Eylül 2008-Şubat 2009 tarihleri arasında değerlendirilen MR incelemelerde izlenen araknoid granülasyonlardan 5mm ve daha büyük olanlar ile sinus çapında %50’den fazla yer kaplayan AGlar çalışmaya dahil edildi. MR incelemeler 3 Tesla MR cihazında gerçekleştirildi. T2 ağırlıklı turbo spin eko; kesit kalınlığı 5mm, TR 3300ms, TE 102ms, FoV 230, rezolusyon 512, averaj 2, Sapma açısı 120°, bant genişliği 100 Hz/Px, voksel boyutu: 0.6×0.4×5.0. İki radyolog tarafından yapılan değerlendirmede AG’ların en geniş boyutu, yerleşimi, morfolojisi, kalvarial ve vasküler yapılarla ilişkisi not edildi. Bulgular: Çalışmaya dahil edilen 20 hastada ortalama yaş 36.3 23 dev AG saptandı. Sağ transvers sinuste 11, solda 9; straight sinüste 1; torculer herofi lide 2 AG ortalama çap 7.9 mm saptandı. İzlenen tüm AG’ların santralinde sinyalsiz odak şeklinde vasküler yapı izlendi ve “nokta işareti” olarak tanımlandı.Nokta işareti ve AG ile vasküler yapı ilişkisi MR venografi ile demonstre edildi. Sonuç: Araknoid granülasyonların tanısında 3T MR görüntüleme güvenilir ve ayrıntılı bilgi sağlamaktadır. Bu çalışmada 5mm’den büyük tüm AG’larda santral vasküler yapı ile uyumlu nokta işareti tanımlanmış ve ayırıcı tanıda yardımcı bir işaret olarak değerlendirilmiştir

3T Mr Imaging Findings of Giant Arachnoid Granulations

Objective: In this study our purpose is to evaluate the giant arachnoid granulations AG with 3T MR imaging. Patients and Methods: Amongst the cranial MR examinations evaluated from September 2008 to February 2009, the AGs larger than 5mms and obliterating the sinus lumen more than 50% were included in the study. MR imaging was performed in a 3 Tesla MR equipment. Sequence parameters were as follows T2 weighted turbo spin echo; slice thickness 5mm, TR 3300ms, TE 102ms, FoV 230, resolution 512, average 2, fl ip angle 120°, bandwidth 100 Hz/Px, voxel 0.6×0.4×5.0. Two radiologists performed the assessment. The largest dimension of AGs, location, morphology, the relationship between the calvarial and vascular structures were noted. Results: In 20 patients included in the study mean age 36.3 years 23 giant AGs were detected. At right transverse sinus 11, left 9; 1 at straight sinus, and 2 at torculer herofi li mean diameter 7.9mm was found. All AGs had a signal void focus at the center which was named as ‘dot sign’. The ‘dot sign’ and its vascular relations are demonstrated by MR venography as well. Conclusion: 3T MR imaging provides detailed and reliable information about AGs. In this study a central vascular structure named as ‘dot sign’ is found in all giants AGs larger than 5mms and defi ned as a helpful sign in the diff erential diagnosis.

Keywords:

arachnoid granulation, pacchionian Body MR imaging, dural sinus,

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