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

✍ Scribed by Marshall S. Sussman; John M. Pauly; Graham A. Wright

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 976 KB
• Volume: 40
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.1910400615

✦ Synopsis

Abstract

Traditional T~2~‐based imaging techniques are geared toward imaging long‐T~2~, species. Traditional techniques are, therefore, not optimal in clinical situations where the information of interest lies in the short‐T~2~ species. T~2~‐selective RF excitation (TELEX) is a technique for obtaining a T~2~‐based contrast that highlights short‐T~2~ values while suppressing long‐T~2~ values‐opposite to traditional T~2~ contrast. Previously, TELEX has been demonstrated qualitatively to highlight only very short‐T~2~ values (T~2~ = 0.001 s). When applied to longer T~2~ values (T~2~ ≈︁ 0.01 s), TELEX becomes sensitive to ΔB~o~ non‐uniformities. This restricts its application to problems in which the T~2~ of interest is very short. In this study, TELEX is characterized quantitatively. Furthermore, a bandwidth broadening scheme is developed that reduces the Δ__B__~o~ sensitivity of TELEX. This permits the technique to be applied to longer T~2~ values. The capabilities and limitations of a practical implementation of TELEX are discussed.