equine; foot; deep digital flexor tendon; magnetic resonance imaging; artifact; magic angle
Abstract :
[en] Ten normal equine isolated limbs were imaged using a knee coil in a 1.5 Tesla magnetic field, with short echo time sequences (TE < 15 ms). Magnetic resonance imaging was performed on each isolated limb in different positions, with and without extension of the metacarpophalangeal joint. Deep digital flexor tendon orientation ranged from 20 to 60 degrees in relation to the static magnetic field. Increased intratendinous signal intensity was observed when the angle between the deep digital flexor tendon and the constant magnetic field approached 55 degrees ("magic angle"). The increased signal intensity was independent from extension of the metacarpophalangeal joint. Recognition of the magic angle phenomenon is essential for proper evaluation of magnetic resonance imaging studies of the equine foot.
Disciplines :
Veterinary medicine & animal health
Author, co-author :
Busoni, Valeria ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Imagerie médicale
Snaps, Frédéric ; Université de Liège - ULiège > Département clinique des animaux de compagnie et des équidés > Imagerie médicale
Language :
English
Title :
Effect of deep digital flexor tendon orientation on magnetic resonance imaging signal intensity in isolated equine limbs - The magic angle effect
Publication date :
2002
Journal title :
Veterinary Radiology and Ultrasound
ISSN :
1058-8183
eISSN :
1740-8261
Publisher :
Amer Coll Veterinary Radiology
Volume :
43
Issue :
5, Sep-Oct
Pages :
428-430
Peer reviewed :
Peer Reviewed verified by ORBi
Commentary :
The definitive version is available at www.blackwell-synergy.com
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