Subcompartmentalization of extracellular extravascular space (EES) into permeability and leaky space with local arterial input function (AIF) results in improved discrimination between high‐ and low‐grade glioma using dynamic contrast‐enhanced (DCE) MRI

Abstract

LTKM with local AIF provides more accurate estimation of physiological parameters and improves discrimination between low-grade and high-grade gliomas as compared with GTKM.

Prospective glioma grading using single-dose dynamic contrast-enhanced perfusion MRI

“…MRI perfusion with a single dose of contrast medium was performed in these patients and prospective grading of the gliomas into low and high grade was undertaken based on a rCBV cut-off value of 3, which has been reported previously. 12,20 Tumours with a rCBV value !3 were considered as high grade and <3 were diagnosed as low grade. Thirtysix patients with different grades of glioma, who were graded using the above cut-off values, were examined using 3 T MRI with an injection of 0.2 mM/kg contrast medium to compare any differences in the haemodynamic parameters.…”

“…The cut-off values were extrapolated and confirmed with the hypothesis that the double-dose perfusion study should not influence the perfusion parameters. 12,20 MRI Patients underwent an MRI protocol that included conventional MRI and DCE-MRI using a 3 T Ingenia MRI system (Philips Healthcare, Best, The Netherlands). Conventional imaging of the brain included T2-weighted turbo spin-echo (TSE) images with repetition time (TR)¼3500 ms, echo time (TE)¼110 ms, number of excitations (NEX)¼1, section thickness¼5 mm, flip angle¼90 , acquisition matrix¼420Â420, field of view (FOV)¼230 mm, reconstructed matrix¼448Â448.…”

“…11,12 The pharmacokinetic LTKM was used to calculate K tr , K ep , V e , V p and l tr . 20 A post-contrast 3D T1-weighted turbo field echo (TFE) sequence was acquired with TR¼7.8 ms, TE¼3.6 ms, NEX¼1, section thickness¼1 mm, flip angle¼8 , acquisition matrix¼240Â222, FOV¼240 mm, reconstructed matrix¼288Â288. Post-contrast T1-weighted spin-echo fast suppression was also performed with TR¼578 ms, TE¼8 ms, NEX¼1, section thickness¼5 mm, flip angle¼70 , acquisition matrix¼244Â184, FOV¼220Â180 mm, reconstructed matrix¼432Â432.…”

“…LTKM analysis has shown that even with a limited scan duration, reliable estimation of pharmacokinetic parameters can be obtained. 20 In a recently published study, perfusion MRI performed better in comparison to other available MRI techniques, such as conventional imaging, spectroscopy, and diffusion tensor imaging, in differentiating low-from high-grade gliomas. It has been observed that relative cerebral blood volume (rCBV) measurement is the best perfusion parameter for predicting glioma grade.…”

“…To resolve the persistence of uptake situation, researchers have used models that assume unidirectional exchange, i.e., from the capillary plasma to the EES 17e19 ; however, the reflux from EES to the plasma space cannot be neglected, especially in a high-permeability situation. Recently, in an attempt to resolve the reflux issue, Sahoo et al 20 proposed the threecompartment leaky tracer kinetic model (LTKM) comprising the plasma permeable compartment where bidirectional flow takes place, and the leakage compartment where unidirectional flow is assumed. LTKM analysis has shown that even with a limited scan duration, reliable estimation of pharmacokinetic parameters can be obtained.…”