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PubMed · 7862963

Brain mapping with functional MR imaging: comparison of gradient-echo--based exogenous and endogenous contrast techniques.

V S Mattay·D R Weinberger·F A Barrios·G S Sobering·K J Kotrla·P van Gelderen·J H Duyn·R H Sexton·C T Moonen·J A Frank
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Abstract

PURPOSE: To compare directly the two most widely used methods of functional magnetic resonance (MR) imaging--dynamic contrast material-enhanced MR imaging and blood oxygenation level-dependent (BOLD) MR imaging. MATERIALS AND METHODS: Five healthy volunteers underwent dynamic contrast-enhanced and BOLD MR imaging with a conventional 1.5-T MR unit during visual stimulation and a dark control state. BOLD studies were performed with a gradient-echo sequence, and dynamic MR imaging was performed with an echo-shifted gradient-echo sequence after intravenous administration of a bolus of gadopentetate dimeglumine. RESULTS: A significantly greater percentage signal change was found with dynamic MR imaging than with the BOLD technique. The extent of area activated was also significantly greater. CONCLUSION: With standard clinical imagers and these gradient-echo-based techniques, greater percentage activation and area of activation can be achieved with dynamic MR imaging than with BOLD MR imaging.

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BrainCerebrovascular CirculationContrast MediaDrug CombinationsGadolinium DTPAHumansImage Processing, Computer-AssistedMagnetic Resonance ImagingMeglumineOrganometallic CompoundsPentetic AcidPhotic StimulationComparative StudyJournal Article

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V S Mattay, D R Weinberger, F A Barrios, G S Sobering, K J Kotrla, P van Gelderen, J H Duyn, R H Sexton, C T Moonen, J A Frank. 1995. Brain mapping with functional MR imaging: comparison of gradient-echo--based exogenous and endogenous contrast techniques.. https://doi.org/10.1148/radiology.194.3.7862963

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