Mean change in Δ1/T1 using oxygen and carbogen inhalation.

Title
Comparison of the Performance of Tracer Kinetic Model-Driven Registration for Dynamic Contrast Enhanced MRI Using Different Models of Contrast Enhancement
Authors
Giovanni A. Buonaccorsi, Caleb Roberts, Sue Cheung, Yvonne Watson, James P.B. O’Connor, Karen Davies, Alan Jackson, Gordon C. Jayson, Geoff J.M. Parker
Journal
Acad. Radiology
Link
http://www.academicradiology.org/article/S1076-6332(06)00312-6/abstract
Year
2006
Volume
13
Number
9
Pages
1112–1123
Month
September
Abstract
RATIONALE AND OBJECTIVES The quantitative analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) data is subject to model fitting errors caused by motion during the time-series data acquisition. However, the time-varying features that occur as a result of contrast enhancement can confound motion correction techniques based on conventional registration similarity measures. We have therefore developed a heuristic, locally controlled tracer kinetic model-driven registration procedure, in which the model accounts for contrast enhancement, and applied it to the registration of abdominal DCE-MRI data at high temporal resolution. MATERIALS AND METHODS Using severely motion-corrupted data sets that had been excluded from analysis in a clinical trial of an antiangiogenic agent, we compared the results obtained when using different models to drive the tracer kinetic model-driven registration with those obtained when using a conventional registration against the time series mean image volume. RESULTS Using tracer kinetic model-driven registration, it was possible to improve model fitting by reducing the sum of squared errors but the improvement was only realized when using a model that adequately described the features of the time series data. The registration against the time series mean significantly distorted the time series data, as did tracer kinetic model-driven registration using a simpler model of contrast enhancement. CONCLUSION When an appropriate model is used, tracer kinetic model-driven registration influences motion-corrupted model fit parameter estimates and provides significant improvements in localization in three-dimensional parameter maps. This has positive implications for the use of quantitative DCE-MRI for example in clinical trials of antiangiogenic or antivascular agents.