The effect of Gd-DTPA on T(1)-weighted choline signal in human brain tumours.

CRC Clinical MR Research Group, The Institute of Cancer Research and The Royal Marsden NHS Trust, Sutton. Surrey, SM2 5PT, United Kingdom.
Magnetic Resonance Imaging (Impact Factor: 2.06). 02/2002; 20(1):127-30. DOI: 10.1016/S0730-725X(02)00485-X
Source: PubMed

ABSTRACT The influence of Gd-DTPA on T(1)-weighted (T(1)W) proton MR spectra has been investigated in 19 patients with histologically verified low (n = 13) or high-grade (n = 6) gliomas. Repeat measurements were performed on 9 patients (7 low-grade and 2 high-grade), with 28 examinations performed in total. Comparison of spectra obtained before and after 0.2 mmol/kg Gd-DTPA showed contrast agent induced broadening of the choline signal without significant signal area change. Lack of enhancement of the choline signal with the T(1)-weighted acquisitions implies that the contrast agent and the trimethylamine-containing species do not undergo significant direct interaction. Contrast agent induced changes in the choline signal observed in this and previous studies may, therefore, be attributable to T2*/susceptibility-based effects.

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