Memik TEKE, Adnan KINA, Özgür SARICA, Sait ALBAYRAM

Nöroradyolojide Susceptibility Weighted Imaging sekansı uygulamaları

Amaç: Klinik uygulamaya yakın zamanda giren Susceptibility Weighted Imaging (SWI) sekansı dokuların manyetik yatkınlık farklarını kullanarak kontrast oluşturan, T1, T2, T2* ve proton dansitesinden farklı yeni bir sekanstır. Çalışmamızda, nöroradyolojide susceptibility weighted imaging sekansının kullanılabilirliği ve lezyon saptamadaki duyarlılığının ortaya konması amaçlandı. Yöntemler: Şubat 2009- Mayıs 2009 tarihleri arasında S.B. Taksim Eğitim ve Araştırma Hastanesinde klinisyen tarafından magnetik rezonans (MR) istemi yapılmış ortalama 51,6 yaşında (Aralık: 5-86) ,93ü (%51,7) kadın ve 87si (%48,3) erkek 180 hasta çalışmaya dahil edildi. Tüm hastalara 1,5-T MR cihazı (Magnetom Avanto; Siemens, Erlangen, Almanya) kullanılarak konvansiyonel sekanslara ek olarak aksiyal T2* ve SWI sekansları ile görüntüler alındı. Hastalar lezyon görülebilirliği ve görünüm özellikleri açısından konvansiyonel ve T2* sekans ile karşılaştırıldı. Bulgular: Çalışmamızda 12 hastada travmatik, 10 hastada notravmatik kanama, 17 hastada kitle, 14 hastada mikrokanama odakları, 18 hastada vasküler malformasyon, 19 hastada iskemik serebral enfarkt, 5 hastada sistemik veya nörodejeneratif hastalığa bağlı serebral minereal birikimi, 8 hastada multiple skleroz ve 48 hastada nonpesifik bulgular saptanmıştır. Toplam 30 hastada ise herhangi bir patolojik bulgu saptanmamıştır. Sonuç: SWI sekansı, anatomik detay kaybı olmaksızın yavaş akımlı vasküler lezyonlar, mikro-makro kanamalar, mineral birikimini saptamada, kranial kitlelerin iç yapısını anlamada ve serebral enfarktlarda hemorajik transformasyonu saptamada duyarlı yeni bir MR sekansıdır.

Suscep tibility Weighted Imaging sequence app lications in neuroradiology

Objective: Susceptibility weighted imaging (SWI) is a novel magnetic resonance technique which uses tissue magnetic susceptibility differences to generate a unique contrast, different from that of spin density, T1, T2, and T2*. The subject of this study is to display the usability and the lesion detection sensitivity of the susceptibility weighted imaging sequence at the various clinic condition in neuroradiology. Methods: Between February 2009 - May 2009 in Taksim Education and Research Hospital 180 patients, 93 (51.7%) females and 87 (48.3%) males and mean age is 51,6 (range between 5-86), are included to this study. T2* and SWI sequences were applied to all patients additional to conventional magnetic resonance imaging (MRI) sequences by using 1,5 Tesla MRI device (Magnetom Avanto; Siemens, Erlangen, Germany). Patients were compared with conventional and T2 * sequences in terms of visibility and appearance characteristics of lesions. Results: In our study, we found out that, 12 patients have traumatic and 10 patients have non-traumatic bleeding, 17 patients have mass, 14 patients have micro bleeding spots, 18 patients have vascular malformations, 19 patients have ischemic cerebral infarct, 5 patients have cerebral mineral depositions which is related to systemic or neurodegenerative disorders, 8 patients have multiple sclerosis and 48 patients have nonspecific findings. In 30 patients no pathologic findings have been found. Conclusion: SWI sequence is a new MRI imaging sequence which is sensitive in detection of pathologies like macro-micro bleeding, mineral depositions, low-flow vascular lesions, internal architecture of the cranial masses, and also showing hemorrhagic transformations in cerebral infarcts without anatomical detail loss.

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