Hui K, Lee G K, Zhang F, Li K, Cheung L, Lineaweaver W C
Division of Plastic and Reconstructive Surgery, Stanford University School of Medicine, California 94305, USA.
Microsurgery. 1996;17(6):306-12. doi: 10.1002/(SICI)1098-2752(1996)17:6<306::AID-MICR4>3.0.CO;2-F.
Contrast-enhanced magnetic resonance imaging (MRI) can be a highly sensitive monitor of tissue blood perfusion. This technique has been used to assess blood flow through liver, kidney, and certain tumors, but has not been widely applied to the study of skeletal muscle circulation. In our study, we used a novel scanning software to obtain contrast-enhanced T2*-weighted gradient echo MRI images of pedicled quadriceps muscle flaps in rabbits in order to study images of arterial, venous, and arterio-venous occlusion. We administered an intravenous bolus of gadoteridol contrast agent at the initiation of scanning, which produces a decrease in T2*-signal and improves the sensitivity of measuring blood perfusion. Within 30 seconds of MRI scanning, control flaps with intact pedicles exhibited a rapid decrease in T2*-signal intensity, indicating adequate perfusion of blood through muscle tissue; however, occluded pedicled flaps showed no significant change in signal intensity, indicating lack of blood perfusion. Differences in signal intensities as measured by MRI between occluded and control flaps were statistically significant (P < 0.05). Selective vascular occlusion of either artery alone, or both artery and vein were detected within 15 minutes, whereas selective venous occlusion could be detected after 2 hours. We conclude that MRI has the ability to assess skeletal muscle perfusion, and is capable of noninvasively evaluating a cross-section of tissue in both superficial and buried flaps. MRI, therefore, may have the potential for evaluating perfusion in muscle flaps (including buried flaps), and other disorders of muscle circulation such as compartment syndrome.
对比增强磁共振成像（MRI）可作为一种对组织血流灌注高度敏感的监测手段。该技术已被用于评估肝脏、肾脏及某些肿瘤的血流情况，但尚未广泛应用于骨骼肌循环的研究。在我们的研究中，我们使用一种新型扫描软件来获取兔带蒂股四头肌肌瓣的对比增强T2加权梯度回波MRI图像，以研究动脉、静脉及动静脉闭塞的图像。在扫描开始时静脉推注钆特醇造影剂，这会使T2信号降低并提高测量血流灌注的灵敏度。在MRI扫描的30秒内，带完整蒂的对照肌瓣T2*信号强度迅速下降，表明肌肉组织有充足的血液灌注；然而，蒂闭塞的肌瓣信号强度无明显变化，表明无血液灌注。MRI测量的闭塞肌瓣与对照肌瓣之间的信号强度差异具有统计学意义（P < 0.05）。在15分钟内可检测到单独动脉或动静脉的选择性血管闭塞，而选择性静脉闭塞在2小时后才可检测到。我们得出结论，MRI有能力评估骨骼肌灌注，并且能够无创地评估表浅和深部肌瓣的组织横截面。因此，MRI可能有潜力用于评估肌瓣（包括深部肌瓣）的灌注以及其他肌肉循环障碍，如骨筋膜室综合征。
