mISIS-CPMG: A Method for Localized Multicomponent T2 Measurement Immune to Very Short T2 Relaxation Effects

Ericky C. A. Araujo¹, Alexandre Vignaud², Paulo L. de Sousa¹, Pierre G. Carlier¹

T2 spectrum measurements in skeletal muscle have revealed four T2 compartments, with T2's ranging from 1 to 200ms. Changes in T2 spectrum may reflect physiological and pathological process. Current methods give accurate results only for T2>10ms. Fast spin-spin relaxation perturbs the response of shorter T2 components to RF pulses, leading to unreliable quantification results. The ISIS technique was modified with the insertion of specially designed quadratic phase pulses, immune to T2 relaxation effects. The modified ISIS was combined to the Carr-Purcell-Meiboom-Gill sequence. The resulting method is suited for localized T2 spectrum measurement including T2 as short as 1ms.