Early marker for Alzheimer's disease: hippocampus T1rho (T(1rho)) estimation.

<bold>Purpose: </bold>To evaluate the T1rho (T(1rho)) MRI relaxation time in hippocampus in the brain of Alzheimer's disease (AD), mild cognitive impairment (MCI), and control, and to determine whether the T(1rho) shows any significant difference between these cohorts.<bold>Materials and Methods: </bold>With informed consent, AD (n = 49), MCI (n = 48), and age-matched control (n = 31) underwent T(1rho) MRI on a Siemens 1.5T Scanner. T(1rho) values were automatically calculated from the left and right hippocampus region using in-house developed software. Bonferroni post-hoc multiple comparisons was performed to compare the T(1rho) value among the different cohorts.<bold>Results: </bold>Significantly higher T(1rho) values were observed both in AD (P = 0.000) and MCI (P = 0.037) cohorts compared to control; also, the T(1rho) in AD was significantly high over (P = 0.032) MCI. Hippocampus T(1rho) was 13% greater in the AD patients than control, while in MCI it was 7% greater than control. Hippocampus T(1rho) in AD patients was 6% greater than MCI.<bold>Conclusion: </bold>Higher hippocampus T(1rho) values in the AD patients might be associated with the increased plaques burden. A follow-up study would help to determine the efficacy of T(1rho) values as a predictor of developing AD in the control and MCI individuals. [ABSTRACT FROM AUTHOR]