Spriet Mathieu, Murphy Brian, Vallance Stuart A, Vidal Martin A, Whitcomb Mary Beth, Wisner Erik R
Department of Surgical and Radiological Sciences, University of California, Davis, CA, USA.
Vet Radiol Ultrasound. 2012 Jul-Aug;53(4):394-401. doi: 10.1111/j.1740-8261.2012.01929.x. Epub 2012 May 2.
Magic angle magnetic resonance (MR) imaging consists of imaging tendons at 55° to the magnetic field. In people, magic angle MR imaging is valuable for detection of chronic tendon lesions and allows calculation of tendon T1 values. Increased T1 values occur in people with chronic tendinopathy. The T1 values of normal equine tendons have been reported but there are no available data for abnormal equine tendons. Twelve limbs were studied. Two limbs had diode laser tendon lesions induced postmortem, four limbs had diode laser tendon lesions induced in vivo and six limbs had naturally occurring tendon lesions. The limbs were imaged at 1.5 T using both conventional MR imaging and magic angle MR imaging. The post-mortem laser induced lesions were identified only with magic angle MR imaging. The in vivo induced lesions and naturally occurring lesions were identified with both techniques but had a different appearance with the two imaging techniques. Magic angle imaging was helpful at identifying lesions that were hypointense on conventional imaging. Increased T1 values were observed in all abnormal tendons and in several tendons with a subjectively normal MR appearance. The increased T1 value may reflect diffuse changes in the biochemical composition of tendons. Magic angle imaging has potential as a useful noninvasive tool to assess the changes of the extracellular tendon matrix using T1 values.
魔角磁共振（MR）成像包括在与磁场成55°角的位置对肌腱进行成像。在人类中，魔角MR成像对于检测慢性肌腱病变很有价值，并且可以计算肌腱的T1值。慢性肌腱病患者的T1值会升高。正常马肌腱的T1值已有报道，但尚无异常马肌腱的相关数据。对12条肢体进行了研究。其中两条肢体在死后诱导产生二极管激光肌腱损伤，四条肢体在活体中诱导产生二极管激光肌腱损伤，六条肢体有自然发生的肌腱损伤。使用传统MR成像和魔角MR成像在1.5T磁场下对这些肢体进行成像。仅通过魔角MR成像才能识别死后激光诱导的损伤。两种技术都能识别活体诱导损伤和自然发生的损伤，但两种成像技术下其表现不同。魔角成像有助于识别在传统成像上呈低信号的病变。在所有异常肌腱以及一些在主观上MR表现正常的肌腱中都观察到T1值升高。T1值升高可能反映了肌腱生化成分的弥漫性变化。魔角成像有潜力作为一种有用的非侵入性工具，利用T1值评估细胞外肌腱基质的变化。
