2010 Volume 69 Issue 6 Pages 338-346
The distribution between hematopoietic bone marrow and fatty bone marrow in normal bone marrow may change with age, and T1 relaxation time of MRI (T1) is useful for quantitative measurement of these distributions. Since there have been almost no reports on T1 of the lumbar spine and pelvic bone, we examined T1 measurements of adult bone marrow (lumbar spine and pelvic bone) using the turbo FLASH method, and compared the differences by age, sex, and site. The subjects were patients and healthy volunteers including 74 males and 147 females without anemia. As a result, shortening of T1 with age was confirmed in both male and female subjects, with female subjects showing a higher correlation, compared to males. In addition, T1 of the pelvic bone was shorter than that of the lumbar spine and was significantly longer in female subjects aged 50 years or younger. Further differences in age and sex were also observed in young female subjects. Since the turbo FLASH method used in this study enables us to perform the T1 measurement in a short period of time, the burden on the subjects would likely be decreased.