Comparison of T2-SENSE, Turbo Spin Echo T2-and T1-weighted MR Sequences for Detection of Liver Lesions

Abstract

Objective: This study aimed to compare ultrafast sensitivity encoding (SENSE) T2-weighted (T2W), turbo spin echo (TSE) T2-W and T1-weighted (T1W) sequences of magnetic resonance imaging (MRI) for detection of liver masses.Materials and Methods: A total of 30 patients with a known or newly detected liver mass were included in the study. All patients underwent respiratory-triggered T2-W SENSE, fat suppressed (SPIR) T2-W SENSE, breath-hold TSE T2-weighted and breath-hold dynamic contrast-enhanced 3-dimensional (3D) T1-FFE sequences. The detected masses were evaluated for size, margins and signal characteristics, and accordingly the groups were formed. Lesions on T2-W sequences divided into distinct groups as soft and sharp contours according to their edges, and light, medium and hyperintense according to the characteristics of the signal. The number of lesions on T2-W sequences was compared with that on T1-weighted sequences. In addition, the number and size of lesions among T2-weighted sequences were compared.Results: The maximum number of lesions was found in SENSE T2-W fat suppressed (SPIR SENSE) sequences. However, in terms of lesion detection sensitivity, no statistically significant difference was found between T2- and T1-W sequences. No significant statistical difference was found in terms of the size of lesions in SENSE T2-weighted SPIR, SENSE TSE T2-W and T2-W sequences. There was no statistical difference in the comparison among T2-W sequences, according to contour and signal characteristics.Conclusion: Ultrafast SENSE T2-W sequences, especially when used in conjunction with fat suppression, are as sensitive as T2-W TSE sequences in detecting liver lesions. The lesion detection sensitivity of contrast-enhanced T1-W images decreases, especially in lesions under 5 mm in size. Contrast-enhanced T1-W images are important in the characterization of the lesions. Ultrafast SENSE T2-W sequences are reliable sequences, which can be used instead of T2-W TSE sequences in liver imaging.

Keywords

• Liver, Lesion, Magnetic Resonance Imaging, Sequence

Karaciğer Lezyonlarının Saptanmasında T2 SENSE, Turbo Spin Eko T2 ve T1 Ağırlıklı MR Sekanslarının Karşılaştırılması

Abstract

Amaç: Bu çalışmada karaciğer kitlelerinin saptanmasında çok hızlı sensitivity encoding (SENSE) T2 ağırlıklı (T2A), turbo spin eko (TSE) T2A ve T1 ağırlıklı (T1A), manyetik rezonans görüntüleme (MRG) sekanslarının karşılaştırılması amaçlanmaktadır.Gereç ve Yöntem: Bilinen karaciğer kitlesi olan veya yeni tespit edilen toplam 30 hasta çalışmamıza dahil edildi. Tüm hastalara solunum tetiklemeli SENSE T2A, yağ baskılı, selective presaturation invertion recovery (SPIR) SENSE T2A, nefes tutmalı TSE T2A ve nefes tutmalı dinamik kontrastlı 3 boyutlu (3B) T1 fast field echo (FFE) sekansları uygulandı. Saptanan kitlelerin, sayı, boyut, kenar ve sinyal özellikleri değerlendirilip buna göre gruplar oluşturuldu. T2A sekanslarda lezyonlar kenar özelliklerine göre silik ve keskin konturlu, sinyal özelliklerine göre ise hafif, orta ve belirgin hiperintens olarak gruplara ayrıldı. T2A sekanslarda elde edilen lezyon sayıları, T1A sekanslarda elde edilen lezyon sayıları ile karşılaştırıldı. Ayrıca T2A sekanslar arasında lezyon sayı ve boyutları açısından karşılaştırma yapıldı.Bulgular: Çalışmamızda yağ baskılı SENSE T2A (SPIR SENSE) sekansta lezyon sayısı en fazla bulundu. Ancak lezyon saptama duyarlılığı açısından istatistiksel olarak T2A sekanslar ile T1A sekanslar arasında anlamlı fark bulunmadı. SPIR SENSE T2A, SENSE T2A ve TSE T2A sekansları arasında lezyon boyutu açısından anlamlı istatistiksel fark bulunmadı. Kontur ve sinyal özelliklerine göre yapılan karşılaştırmada T2A sekanslar arasında istatistiksel fark saptanmadı.Sonuç: SENSE T2A çok hızlı sekanslar, özellikle yağ baskılama ile birlikte kullanıldıklarında, karaciğer lezyonlarını saptamada, TSE T2A sekans kadar duyarlıdır. Çok hızlı SENSE T2A sekanslar, TSE T2A sekansların yerine karaciğer görüntülenmesinde kullanılabilecek güvenilir sekanslardır.

Keywords

• Karaciğer, Lezyon, Manyetik Rezonans Görüntüleme, Sekans

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