M Nazarpoor - Department of Radiology, Paramedical School, Tabriz University of Medical Science, Tabriz, Iran

A T1 technique has applied for calculating tissue bloodflow to MR cerebral perfusion scanning. Using T1-weighted images for a perfusion study needs about1/10th of the contrast agent that is normally used for aT2¤-weighted acquisition. This method has been usedfor measuring blood flow in a range of organs suchas the liver, kidneys, spleen, pancreatic and brain innuclear medicine and CT. Previous study shows thatthe cerebral blood flow (CBF) calculated from the T1technique was lower than the expected CBF. In thisstudy the validation and reproducibility of the T1 techniquewas assessed ( after inflow and coil non uniformitycorrections) using in vitro experiment at differentflow rates and two different concentrations (0.8 and 1.2mmol/L).After the two corrections, the results indicate thatthe T1 technique can be used to measure the absoluteflow, where the flow rate is low, such as capillaries.It seems that for measuring the high flow rate (e.g.in an artery) some additional correction factor due toinaccurate measurement of the maximum gradient oftissue (or organ) should be considered.

MRI: Inversion recovery; Centre out Phase-Encoding acquisition; T1-weighted image; Flow; T1 technique