Magnetic resonance (MR) imaging of the carpal tunnel and related structures in New Zealand Rabbit (Oryctolagus cuniculus): An anatomic and radiologic evaluation on an animal model

Abstract

The aim of this study was to determine the anatomical structures in carpal region with the routine T1, T2 weighted (W) and three-dimensional (3D) magnetic resonance (MR) sequences that are frequently being used for the diagnosis and the treatment of the wrist disorders and to indicate the efficacy of MR imaging (MRI) on the rabbit’s carpal region which can be a convenient wrist model especially for the carpal tunnel syndrome. It is also aspired to compare the image features obtained from 1.5 and 3 Tesla MR units in terms of anatomy and radiology. Five adult New Zealand rabbits were used in this study. Wrists were scanned in neutral position by 1.5 and 3 Tesla MR devices with a loop coil and a 15-channel transmit-receive birdcage coil respectively. Anatomy of the carpal tunnel was well defined in T1W transverse images in 1.5 Tesla MRI. The median nerve was imaged with greater signal intensity on T2W sequences. In 3 Tesla MRI, the anatomical structures in carpal region could easily be evaluated on high resolution 3D sequences with isotropic voxels and also with the help of thin section reformatted images. According to our results, 3D sequences with isotropic voxel sizes by 15-channel transmit-receive birdcage coil in 3 Tesla MRI device seems to be more efficient than the other routine two-dimensional sequences in 1.5 Tesla MRI for the assessment of carpal tunnel anatomy, diagnosis and treatment of disorders both in humans and in animals. This process also decreases the MRI time and specific absorption rate (SAR) values

Keywords

• 15 channel transmit-receive coil
• anatomy
• carpal tunnel
• magnetic resonance imaging
• rabbit

Yeni Zelanda Tavşanı’nda (Oryctolagus cuniculus) karpal tünel ve ilişkili yapıların manyetik rezonans(MR) görüntülenmesi: Hayvan modeli üzerinde anatomik ve radyolojik bir değerlendirme

Abstract

Bu çalışmanın amacı; el bileği bölgesindeki rahatsızlıkların teşhis ve tedavisinde kullanılan rutin T1, T2 Ağırlıklı (A) ve 3 boyutlu manyetik rezonans (MR) sekanslarının yardımıyla, karpal bölgedeki anatomik oluşumları belirlemek ve manyetik rezonans görüntülemenin, özellikle karpal tünel sendromu için uygun bir bilek modeli olabilecek tavşan karpal bölgesi üzerindeki etkinliğine işaret etmektir. Ayrıca 1,5 ve 3 Tesla MR cihazlarından elde edilen görüntü özelliklerinin anatomik ve radyolojik açıdan karşılaştırılması da amaçlanmıştır. Bu çalışma için 5 adet Yeni Zelanda Tavşanı’ndan faydalanılmıştır. El bilekleri nötral pozisyonda sırasıyla 1,5 Tesla MR cihazında, halka tipi koil ile ve 3 Tesla MR ünitesinde, 15 kanallı alıcı-verici kafes tipi koil ile tarandı. 1,5 Tesla MR görüntülemede; T1 A transversal imajlarda carpal tünel daha iyi belirlendi. T2 A sekanslarda nervus medianus yüksek sinyal yoğunluğu gösterdi. 3 Tesla MR görüntülemede; karpal bölgedeki anatomik yapılar izotropik vokselli 3 boyutlu sekanslar ve ayrıca ince kesit reformat görüntülerin de yardımıyla rahatlıkla değerlendirilebildi. Sonuçlarımıza göre; hem insan hem de hayvanlarda karpal tünel anatomisinin değerlendirilmesi, rahatsızlıkların teşhis ve tedavisi için izotropik voksel 3 boyutlu sekanslar ve 15 kanal alıcı-verici koil vasıtasıyla çekilen 3 Tesla MR görüntülemenin, 1,5 Tesla MR görüntülemede kullandığımız 2 boyutlu sekanslara göre daha etkin olduğu görülmektedir. Ayrıca bu işlem MR görüntüleme zamanını kısaltmakta ve SAR değerlerini de düşürmektedir

Keywords

• 15 kanallı alıcı-verici koil
• anatomi
• karpal tünel
• manyetik rezonans görüntüleme
• tavşan

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