Design and optimization of ultra-short echo-time sequence for reliable detection of myelin content in the human brain by magnetic

The aim of the project is to design and optimize an ultra-short echo-time pulse sequence for a direct measurement of the short-T2 signals arising from white matter of the brain. There are two main obstacles to a reliable detection of myelin sheaths: 1) their signal decays to zero in a few tens of microseconds; and 2) their signal is overwhelmed by the predominant long-T2 components from white matter of the brain. The unique feature of the pulse sequence design will be a calibration procedure correcting for eddy-current induced image distortions, based on the measurement of k-space trajectory during the gradient ramp-up. The complete removal of residual long-T2 components will be achieved by optimized dual echo acquisition and subtraction, which will selectively depict signal from the short-T2 components. Following the technical development, a pilot study including healthy and multiple sclerosis volunteers will be performed to demonstrate the capabilities of the newly developed methodology for the direct myelin measurement.