Absolute Quantification in 1H MRSI of the Prostate at 3T

Paul Michael Walker^1,2, Gilles Crhange³, Sbastien Parfait², Alexandre Cochet¹, Philippe Maingon³, Luc Cormier¹, Franois Brunotte^1,2

Although, it is common in MRSI to use a Choline/Citrate ratio when evaluating PCa, the use of citrate (Cit) as a reference is questionable in the context of treatment such as hormonotherapy and radiotherapy, because Cit levels fall very sharply even in non-cancerous tissue. We have proposed an absolute quantification method at 3T and we observed significantly higher Cit in normal PZ than in CG tissue. However, in PCa, reductions in Cit were not accompanied by important increases in tCho, suggesting increases in tCho/Cit are primarily due to loss of Cit and not to a sharp rise in tCho.