Mair Tim S, Kinns Jen
Bell Equine Veterinary Clinic, Mereworth, Maidstone, Kent ME18 5GS, UK.
Vet Radiol Ultrasound. 2005 Nov-Dec;46(6):458-66. doi: 10.1111/j.1740-8261.2005.00084.x.
Injury to the distal aspects of the deep digital flexor tendon (DDFT) is an important cause of lameness in horses. The purpose of this study was to review the magnetic resonance imaging (MRI) findings of 18 horses affected by DDFT injuries in the foot. The MRI was performed with the horses standing using an open low-field (0.21 T) MRI scanner. The results were compared with those previously reported for horses using high-field MRI. Eighteen of 84 horses (21%) with undiagnosed forefoot pain were found to have lesions affecting the DDFT. The history, clinical findings and results of radiography, diagnostic ultrasonography and nuclear scintigraphy of these horses were reviewed. The duration of lameness ranged from 1 to 12 months, and the severity varied from 1/10 to 6/10. Fifteen horses had unilateral lameness (right fore in nine, left fore in six), whereas three horses were bilaterally foreleg lame. Radiological changes, considered of equivocal significance, were found in six of 18 horses. Ultrasonographic changes involving the DDFT were identified in only one of nine horses. DDFT lesions were detected in both T1- and T2-weighted MRI sequences. Four different types of lesions were identified: core lesions, sagittal splits, dorsal border lesions, and insertional lesions. Combinations of different lesion types within the same horse were common. The types and locations of the DDFT lesions were similar to those previously reported using high-field MRI. The use of low-field standing MRI avoids the necessity for general anesthesia and access to conventional high-field MRI scanners. However, studies comparing the results of standing low-field MRI with high-field MRI (and other imaging procedures) are required before the sensitivity and specificity of the technique can be assessed.
指深屈肌腱(DDFT)远端损伤是马跛行的一个重要原因。本研究的目的是回顾18匹足部受DDFT损伤的马的磁共振成像(MRI)结果。MRI检查时马站立,使用开放式低场(0.21 T)MRI扫描仪进行。将结果与之前使用高场MRI对马的报告结果进行比较。在84匹未确诊前足疼痛的马中,有18匹(21%)被发现存在影响DDFT的病变。回顾了这些马的病史、临床检查结果以及X线摄影、诊断性超声检查和核素闪烁扫描的结果。跛行持续时间为1至12个月,严重程度从1/10到6/10不等。15匹马为单侧跛行(右前肢9匹,左前肢6匹),而3匹马为双侧前肢跛行。18匹马中有6匹发现有意义不明确的放射学改变。9匹马中只有1匹发现有涉及DDFT的超声改变。在T1加权和T2加权MRI序列中均检测到DDFT病变。识别出四种不同类型的病变:核心病变、矢状劈裂、背侧边缘病变和附着点病变。同一匹马内不同病变类型的组合很常见。DDFT病变的类型和位置与之前使用高场MRI报告的相似。使用低场站立式MRI避免了全身麻醉的必要性,并且无需使用传统的高场MRI扫描仪。然而,在评估该技术的敏感性和特异性之前,需要进行将站立式低场MRI结果与高场MRI(以及其他成像检查)结果进行比较的研究。