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Updated: May 14, 2026

Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring
Published on: December 9, 2010
Study of magnetization evolution by using composite spin-lock pulses for T₁ρ imaging
Yujia Li1, Feng Zhao, Yi-Xiang Wang
1Department of Imaging and Interventional Radiology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong. yjli@cuhk.edu.hk
Abstract:
B(0) and B(1) field inhomogeneities may generate banding-like artifacts in T(1ρ)-weighted images and hence result in errors of T(1ρ) quantification. Several types of composite spin-lock pulses have been proposed to alleviate such artifacts. In this study, magnetization evolution with T(1ρ) and T(2ρ) relaxation by using these composite spin-lock pulses are theoretically derived. The effectiveness and limitation of each spin-lock pulse are explicitly illustrated in mathematical forms and phantom T(1ρ)-weighted images acquired by using each spin-lock pulse are presented. This study also provides a theoretical framework for T(1ρ) quantification from T(1ρ)-weighted images even with B(0) and B(1) inhomogeneity artifacts.
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