FIGURE 4.  Percentage of patients (according to decade of life) in whom MTA exceeded empiric dosing. Empiric dose above 7.4 GBq (200 mCi) exceeded MTA in large proportion of patients more than 60 y old (14% of patients 60–69 y old and 22% of those 70–79 y old). Empiric dose of 9.25 GBq (250 mCi) would exceed MTA in 22% of patients 60–69 y old and in 50% of those 70 y old or older.