Delayed contrast agent kinetics in ischemic skeletal muscle

Nygren, Anders; Greitz, Dan

doi:10.1002/jmri.20482

Cited by 4 publications

(4 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Contrast enhanced ultrasound, although specific for microvasculature, uses projection imaging and is only able to assess superficial muscles (22). Dynamic contrast enhanced (23,24) and arterial spin labeling (25) MRI allow for direct evaluation of the microvasculature, but the former uses gadolinium-based contrast agents and the latter does not have the high time resolution require to evaluate hemodynamic changes following brief skeletal muscle contractions.…”

Section: Introductionmentioning

confidence: 99%

Repeatability of a dual gradient‐recalled echo MRI method for monitoring post‐isometric contraction blood volume and oxygenation changes

et al. 2009

View full text Add to dashboard Cite

The purpose of this study was to assess the repeatability of a dual gradient-recalled echo (GRE) muscle functional MRI technique. On two days, subjects (n=8) performed 10 s isometric dorsiflexion contractions under conditions of: 1) maximal voluntary contraction (MVC), 2) 50% MVC (50%MVC) or 3) 50% MVC with concurrent proximal arterial cuff occlusion (50%MVCcuff). Functional MRI data were acquired using single-slice dual GRE (TR/TE=1000/6, 46 ms) EPI for 20 seconds before, during, and for 180 seconds after each contraction. The mean signal intensity (SI) time courses at each TE (SI6 and SI46, reflecting variations in blood volume and %HbO2, respectively) from the tibialis anterior (TA) and extensor digitorum (EDL) muscles were characterized with the post-contraction change in SI and the time to peak SI (ΔSI and TTP, respectively). ΔSI6 and ΔSI46 were 36% and 31% higher following an MVC than after a 50%MVC (p = 0.05 and p = 0.07 respectively). For ΔSI6 the highest intraclass correlation coefficients (ICC) were observed for the TA muscle at the 50%MVC and MVC condition, with values of 0.83 (p = 0.01) and 0.88 (p = 0.005), respectively. Bland-Altman plots revealed repeatability coefficients (RC) for the 50%MVC and MVC conditions in the TA muscle of 1.9 and 1.4, respectively. The most repeatable measures for ΔSI46 were obtained for the 50%MVC and MVC conditions in the EDL muscle (p = 0.01 and p = 0.04, respectively). Bland-Altman plots revealed RC’s for 50%MVC and MVC conditions in the EDL muscle of 3.9 and 5.7, respectively. ΔSI6 and ΔSI46 increased as a function of contraction intensity. The repeatability of the method depends on the muscle and contraction condition being evaluated, and in general, is higher following an MVC.

show abstract

Section: Introductionmentioning

confidence: 99%

Repeatability of a dual gradient‐recalled echo MRI method for monitoring post‐isometric contraction blood volume and oxygenation changes

et al. 2009

View full text Add to dashboard Cite

show abstract

“…Another factor to be considered when evaluating the T2 response to exercise is that inactivity or less intense active muscles during exercise can affect the interpretation of the T2 response. Therefore, some findings from a gadolinium (Gd)‐enhanced first‐pass kinetics study were incorporated into the present analysis (10).…”

mentioning

confidence: 99%

Shortened T2 after exercise in ischemic skeletal muscle

Nygren

2005

Magnetic Resonance Imaging

Self Cite

View full text Add to dashboard Cite

Purpose: To detect skeletal muscle ischemia with transverse relaxometry after ischemic exercise. Materials and Methods:Ten subjects with intermittent claudication were studied. T2 was measured in the gastrocnemius and soleus muscles (m. gastrocnemius and m. soleus) at rest and repeatedly after exercise during 45 minutes of recovery. Prior to MRI a symptom-limited treadmill exercise was performed, and the ankle-arm blood pressure index (AAI) was measured at rest and after exercise. Results:In the 14 legs with ischemic pain, a diverging response was found in the calf: T2 increased in m. gastrocnemius by 5.6% Ϯ 4.9%, but decreased in m. soleus by -1.2% Ϯ 4.4% (P Ͻ 0.001). Moreover, 13 regions in legs with ischemic pain and reduced AAI (from 0.7 Ϯ 0.2 at rest to 0.31 Ϯ 0.15 after exercise) had shortened T2 (-3.6% Ϯ 1.8%) immediately after exercise. This finding was most frequent in m. soleus and two regions of m. gastrocnemius. Recovery was delayed in the latter two regions. Conclusion:T2 may identify ischemic muscles after hypoxic exercise. Shortened T2 suggests a reduced water content (e.g., distribution volume of water) and may affect the upslope kinetics of an extravascular perfusion tracer. The different responses to ischemia by the soleus and gastrocnemius muscle may be due in part to their different fiber type compositions.

show abstract

“…e In comparison to healthy volunteers (n=33) and patients, in whom suspected myositis has not been confirmed histologically and by clinical course (n=24), patients with histologically proven dermatomyositis (n=8) and polymyositis (n=3) have significantly increased skeletal muscle perfusion (data on 35 patients with initially suspected myositis [29, 52]) ison to asymptomatic legs, in symptomatic legs the time to contrast arrival is delayed and the curves have a less steep upslope (Fig. 2) [56]. Moreover, preliminary results indicate that with perfusion MRI techniques, effects of regional interventional techniques, such as balloon dilatation, or therapies that stimulate angiogenesis, can be evaluated.…”

Section: Mrimentioning

confidence: 95%

“…In contrast to CEUS, only indirect parameters of perfusion can be measured. [21,22,56]. Characteristic curve segments are the linear upslope (wash-in) reaching a maximum intensity, i.e., peak enhancement.…”

Section: Contrast-enhanced Mrimentioning

confidence: 99%

Quantitative evaluation of muscle perfusion with CEUS and with MR

2007

View full text Add to dashboard Cite

Functional imaging might increase the role of imaging in muscular diseases, since alterations of muscle morphology alone are not specific for a particular disease. Perfusion, i.e., the blood flow per tissue and time unit including capillary flow, is an important functional parameter. Pathological changes of skeletal muscle perfusion can be found in various clinical conditions, such as degenerative or inflammatory myopathies or peripheral arterial occlusive disease. This article reviews the theoretical basics of functional radiological techniques for assessing skeletal muscle perfusion and focuses on contrast-enhanced ultrasound (CEUS) and magnetic resonance imaging (MRI) techniques. Also, the applications of microvascular imaging, such as in detection of myositis and for discriminating myositis from other myopathies or evaluating peripheral arterial occlusive disease, are presented, and possible clinical indications are discussed. In conclusion, dedicated MR and CEUS methods are now available that visualize and quantify (patho-)physiologic information about microcirculation within skeletal muscles in vivo and hence establish a useful diagnostic tool for muscular diseases.

show abstract

Delayed contrast agent kinetics in ischemic skeletal muscle

Cited by 4 publications

References 33 publications

Repeatability of a dual gradient‐recalled echo MRI method for monitoring post‐isometric contraction blood volume and oxygenation changes

Repeatability of a dual gradient‐recalled echo MRI method for monitoring post‐isometric contraction blood volume and oxygenation changes

Shortened T2 after exercise in ischemic skeletal muscle

Quantitative evaluation of muscle perfusion with CEUS and with MR

Contact Info

Product

Resources

About