MRI

Authors: ANNAMARIA NAGY , SUE DYSON
Journal: Veterinary Radiology & Ultrasound

While low-field magnetic resonance (MR) images can provide useful information in the investigation of proximal metacarpal region pain, an in-depth knowledge of anatomy and comparison with more detailed high-field images are essential to understand the meaning of different signal intensities within tissues. This anatomic description is based on low-field and high-field MR examination of 30 cadaver metacarpal regions of mature horses with no history of carpal or proximal metacarpal pain.

Category: Anatomic study - Equine - MRI
Authors: Dakin, S.G.; Dyson, S.J.; Murray, R.C.; Newton, R.
Journal: Equine Veterinary Journal

Reasons for performing study: There are currently few long-term follow-up data relating to recovery from injury of a collateral ligament (CL) of the distal interphalangeal (DIP) joint and limited information about the effect of associated osseous injury on prognosis.

Objectives: To describe long-term follow-up results for horses with CL injury, with and without associated osseous injury; and to determine the effect of extracorporeal shock wave therapy (ECSWT) or radial pressure wave therapy (RPWT) on outcome.

Category: Bone - Equine - Ligament - MRI
Authors: Dakin, S.G.; Dyson, S.J.; Murray, R.C.; Tranquille, C.
Journal: Equine Veterinary Journal

Reasons for performing study: Osseous abnormalities associated with collateral ligament (CL) injury of the distal interphalangeal (DIP) joint have been documented using magnetic resonance imaging (MRI) but there is currently limited information about the frequency of osseous pathology associated with CL injury.

Category: Bone - Equine - Ligament - MRI
Authors: R. C. Murray, MA, VetMB, MS, DipECVS, DipACVS, PhD, MRCVS, T. S. Mair, BVSc, PhD, DipECEIM, EIM, DESTS, MRCVS, C. E. Sherlock, BVetMed, MRCVS and A. S. Blunden, BVetMed, PhD, MRCPath, MRCVS
Journal: Veterinary Record

Eleven limbs taken postmortem from 10 lame horses were examined by MRI in a low-field 0·27T system designed for standing horses and a high-field 1·5T system used to examine anaesthetised horses. Nine limbs were examined in the foot/pastern region and two in the fetlock region, and the results were compared with gross pathological examinations and histological examinations of selected tissues.

Category: Equine - Imaging - MRI
Authors: SARAH N. SAMPSON , ROBERT K. SCHNEIDER , PATRICK R. GAVIN , CHARLES P. HO , RUSSELL L. TUCKER , ELIZABETH M. CHARLES
Journal: Veterinary Radiology and Ultrasound

Seventy-two horses with recent onset of navicular syndrome and normal radiographs were assessed. Horses underwent magnetic resonance (MR) imaging of both front feet. All abnormalities were characterized and the most severe abnormality identified, if possible. Abnormal signal intensity in the navicular bone was the most severe abnormality in 24 (33%) horses. Pathologic change in the deep digital flexor tendon was the most severe abnormality in 13 (18%) horses. Pathologic change in the collateral sesamoidean ligament was the most severe abnormality in 11 (15%) horses.

Category: Equine - Imaging - MRI
Authors: Pauwels, F.E.; Schumacher, J.; Mayhew, I.G.; van Sickle, D. C.
Journal: Equine Veterinary Journal

Neurectomy of the deep branch of the right lateral plantar nerve was performed on a single healthy mature horse. Six weeks after surgery, the horse was subjected to euthanasia and both hind suspensory ligaments harvested. The cross sectional area of the muscular part of the proximal part of the suspensory ligament was measured and assessed for morphological abnormalities in a blinded fashion. There was a clear difference in cross sectional area of the muscular part between treated and control ligament and there was profound neurogenic atrophy of the muscular fibres in the treated ligament.

Category: Equine - Imaging - Ligament - MRI
Authors: Spriet, M.; Zwingenberger, A.
Journal: Equine Veterinary Journal

Reasons for performing study: Hyperintense signal is sometimes observed in ligaments and tendons of the equine foot on standing magnetic resonance examination without associated changes in size and shape. In such cases, the presence of a true lesion or an artifact should be considered. A change in position of a ligament or tendon relative to the magnetic field can induce increased signal intensity due to the magic angle effect.

Category: Equine - Imaging - Ligament - MRI - Tendon
Authors: Chris D. Bell, DVM; Rick D. Howard, DVM, PhD, DACVS; D. Scott Taylor, DVM, DACVS; Ed D. Voss, DVM, DACVIM; Natasha M. Werpy, DVM, DACVR
Journal: Journal of the American Veterinary Medical Association

Objective—To determine clinical outcome following intrathecal injection of the podotrochlear (navicular) bursa for signs of foot pain in horses evaluated via magnetic resonance imaging (MRI) and evaluate efficacy of corticosteroids administered with or without hyaluronate.

Design—Retrospective case series.

Animals—23 horses.

Procedures—Data collected included signalment, history, intended use, duration and severity of lameness, results of diagnostic anesthesia, radiographic abnormalities, MRI abnormalities, and outcomes for return to use.

Category: Equine - Imaging - Lameness - MRI - Treatment
Authors: Olive, J.; Mair, T.S.; Charles, B.
Journal: Equine Veterinary Education

Bone marrow lesions (BMLs) (also known as 'bone bruises', 'bone oedema', 'bone contusions' and 'occult fractures') within the middle phalanx were diagnosed by standing low field magnetic resonance imaging (MRI) in 7 horses. The lesions were characterised by low signal intensity on T1- and T2*-weighted gradient echo sequences, mildly increased signal intensity on T2 fast spin echo sequences, and high signal intensity on short tau inversion recovery (STIR) sequences.

Category: Bone - Equine - Imaging - MRI
Authors: MATHIEU SPRIET , ALEXIA McKNIGHT
Journal: Veterinary Radiology and Ultrasound

Three isolated equine limbs were imaged with a low-field magnetic resonance system with a vertical magnetic field. Each limb was scanned in multiple positions with mild variation of the angle between the magnetic field and the long axis of the limb. When the long axis of the limb was not perpendicular to the magnetic field, a linear hyperintense signal was present at the palmar aspect of one of the deep digital flexor tendon lobes, at the level of the navicular bone and collateral sesamoidean ligaments, in proton density and T1-weighted pulse sequences.

Category: Equine - Imaging - MRI - Tendon