Evaluation of perianal fistulas with magnetic resonance imaging: Significance of T2-weighted BLADE sequence in disease diagnosis

Abstract

Introduction: Anatomical details of perianal fistulas can be revealed more clearly by T2-weighted (T2-W) periodically rotated overlapping parallel lines with enhanced reconstruction (BLADE)sequence during magnetic resonance imaging (MRI). This study aimed to compare the efficacy of the T2-W BLADE sequence and the T2-W turbo spin-echo (TSE) sequence in diagnosing perianal fistula, as well as to compare the findings with the results obtained using the dynamic contrast-enhanced (DCE) T1-weighted (T1-W) sequence during routine pelvic MRI examination. Methods: Ninety patients (M/F: 67/23) who had undergone pelvic MRI examination (1.5Tesla) for the prediagnosis of perianal fistula were included in this prospective study. In addition to our routine pelvic MRI protocol, T2-W BLADE sequence imaging and T2-W TSE sequence imaging in the axial, sagittal, and coronal planes were performed. Using a three-stage scoring system, two radiologists independently compared the T2-W BLADE and T2-W TSE sequences with each other and then with the DCE T1-W sequence in terms of perianal fistula imaging. Statistical analysis was performed using a sample t-test and the Cronbach’s α test. Results: Compared with the T2-W TSE sequence, the T2-W BLADE sequence was associated with fewer ghosting artifacts, higher overall image quality, and with clearer visualization of the anatomical details of the perianal fistula (p < 0.05). Images with high anatomic details and contrast resolution were obtained using the T2-W BLADE sequence similar to those obtained using the DCE T1-W sequence (p < 0.05). Conclusion: On the basis of the reduced imaging time and on the higher image resolution, T2-W images can be obtained with the BLADE technique for the diagnosis of perianal fistula.

Keywords

• Magnetic Resonance Imaging
• Perianal fistula
• artifacts
• T2-weighted sequence
• BLADE technique

Perianal fistüllerin manyetik rezonans görüntüleme ile değerlendirilmesi: T2 ağırlıklı BLADE sekansının hastalık tanısında önemi

Öz

Giriş ve Amaç: Manyetik Rezonans Görüntüleme (MRG) ile perianal fistül teşhisinde, T2-ağırlıklı (A) BLADE sekansın etkinliğini, T2-A Turbo Spin Eko (TSE) sekans ile karşılaştırmak ve bulguları, rutin pelvik MRG incelemede Dinamik Kontrastlı (DCE) T1-A sekans görüntüleri ile karşılaştırmak. Gereç ve Yöntemler: Perianal fistül ön tanısı ile pelvik MRG incelemesi (1.5Tesla) yapılan toplam 90 hasta prospektif çalışmamıza dahil edildi. Rutin pelvik MRG protokolümüze, üç planda T2A BLADE sekansı ve T2A TSE sekansları da dahil edildi. Perianal fistül tanısında T2A BLADE sekans ve T2A TSE sekansların üstünlüğünü birbiriyle ve ardından üç aşamalı skorlama ile DCE T1A sekans ile karşılaştırıldı. Değerlendirme iki radyolog tarafından, farklı zamanlarda ve birbirinden bağımsız olarak yapıldı. İstatistiksel analiz için Simple t-test ve Cronbach's Alpha testi kullanıldı. Bulgular: Perianal fistül tanısında, T2A BLADE sekans ile T2A TSE sekansa göre daha kısa sürede ve artefaktlara daha az duyarlı, yüksek çözünürlüklü görüntüler elde edildi(p <0.05). T2A BLADE sekans ile DCE T1A sekansına benzer yüksek kontrast çözünürlüğü olan görüntüler elde edildi (p <0.05). Sonuç: Daha kısa sürede ve yüksek çözünürlüklü görüntüler elde edebilmesi nedeniyle, perianal fistül tanısında T2A görüntüler BLADE tekniği ile elde edilebilir.

Anahtar Kelimeler

• Manyetik Rezonans Görüntüleme,
• Perianal fistül
• artefaktlar
• T2 ağırlıklı sekans

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