T1 and T2 relaxation times on gadolinium-diethylenetriaminepentaacetic acid enhanced magnetic resonance images of brain tumors.

Abstract

MRI of brain tumors was performed with CPMG pulse sequence, and T1 and T2 relaxation times were measured before and after the administration of 0.1 mmol/kg Gd-DTPA. T1 and T2 became significantly shorter than before with the T1 shortening being about twice the T2's. Three types of T2 shortening were classified by the difference in the intra-tumoral transport of Gd-DTPA in the time-course study after the administration. Transportal activity of Gd-DTPA seemed to be reflected by the physiologic viability of tumor suggested by pre-contrast T2. magnetic resonance imaging ; brain tumor ; gadolinium-DTPA ; Carr-Purcell-Meiboom-Gill pulse sequence ; relaxation time A paramagnetic contrast agent, gadolinium-diethylenetriaminepentaacetic acid (Gd-DTPA), has successfully increased the sensitivity for detection of cerebral abnormalities in magnetic resonance (MR) images, and given the characterization of pathologic conditions (Carr et al. 1984;Felix et al. 1985;Graif et al. 1985). According to the clinical use of the contrast agent for the enhancement in MR images, quantitative analysis is desirable to consider the relation between Gd-DTPA enhancement and patho-physiologic tissue characteristics (Graif et al. 1985). In this study, the contrast enhancement of brain tumors induced by Gd-DTPA was quantitatively evaluated by the changes of T1 and T2 relaxation times.

Blood-brain barrier breakdown in non-enhancing multiple sclerosis lesions detected by 7-Tesla MP2RAGE ΔT1 mapping

“…Dynamic contrast-enhanced (DCE) MRI studies suggest increased permeability in non-enhancing WMLs and NAWM in patients with MS [7]. Alterations in T 1relaxation time, which is shortened in the presence of gadolinium [8], have also been used as a measure of BBB integrity. Multiple studies have found T 1 shortening in both enhancing and non-enhancing WMLs [9].…”

An experimental phantom study of the effect of gadolinium-based MR contrast agents on PET attenuation coefficients and PET quantification in PET-MR imaging: application to cardiac studies

“…2 for comparison to the data derived from the mixture model and from CT imaging only. Studies have shown in vivo the T1- and T2-shortening effects due to the use of GBCA in contrast enhancement studies, with a range from 30 to 68% shortening of T1 post administration of 0.1 mmol/kg body weight [13]. The effect of GBCA on clinically derived MR attenuation maps has recently been demonstrated [14], showing an overestimation of image-based activity concentration due to an assignment of part of the lung tissue to the soft tissue by the MRAC due to the presence of GBCA.…”

Optimization of Brain T2 Mapping Using Standard CPMG Sequence In A Clinical Scanner

“…It has been shown that measurement of the change in T 2 provides important information about the mobility and chemical environment of the tissues of interest [4], [9] - [11]. Previous studies examining the utility of T 2 mapping in the context of neurologic and psychiatric disease demonstrated variations in T 2 values, sometimes very subtle, in specific brain regions within conditions of autism [12], schizophrenia [13], [14], epilepsy [15], Parkinson's [16], multiple sclerosis [17], [18], Alzheimer disease [9], tumors [19], [20], [21] and a host of other disorders [6], [14], [16], [22], [23]. Nevertheless, mapping the T 2 parameter is rarely used in clinical diagnostics, the most common reported reasons being higher scanning times [4], [6], [10], [11] or its lack of specificity, in contrast to its high sensitivity [5], [6], [17], [24].…”