Design of practical T2‐selective RF excitation (TELEX) pulses

Traditional T2‐based imaging techniques are geared toward imaging long‐T2, species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short‐T2 species. T2‐selective RF excitation (TELEX) is a technique for obtaining a T2‐based contrast that highlights short‐T2 values while suppressing long‐T2 values‐opposite to traditional T2 contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short‐T2 values (T2 = 0.001 s). When applied to longer T2 values (T2 ≈︁ 0.01 s), TELEX becomes sensitive to ΔBo non‐uniformities. This restricts its application to problems in which the T2 of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the ΔBo sensitivity of TELEX. This permits the technique to be applied to longer T2 values. The capabilities and limitations of a practical implementation of TELEX are discussed.