Article Figures & Data
Figures
- FIGURE 1.
Activity infusion rate data and fit for sample bolus from February 9, 2017, with fit parameters for growth-saturation curve of form
. - FIGURE 2.
Peak activity infusion rate for each study from one representative generator as function of generator age. Amplitude of activity rate curve did not decrease exponentially with generator age as expected. There is also up to 10% variation in peak activity rates within a single day.
- FIGURE 3.
Best fit bands for 4 activity levels and time to elute each, as function of generator age. Each band contains 95% of data points for each injected activity level. Data are combined from 3 separate 82Rb generators. Top image is with anomalous results from day 24; bottom image is without.
- FIGURE 4.
Peak activity injection rate for each elution, compared with time since last elution. Lines connect data from same day, such that points come from same generator age. Ten minutes is minimum spacing for clinical use, and no studies had time of less than this value since last elution. On the basis of secular equilibrium assumptions, 82Rb/82Sr ratio should be 99.7% of its maximum at 10 min. Elution continues to produce higher peak activity rates with resting times up to 3 h, the longest time measured.
Tables
- TABLE 1.
Fit Parameters for Time to Elute Certain Activity Levels as Function of Generator Age, Following Functional Form
Fit (mCi) y intercept (y0) (s) Amplitude (A) (s) Growth constant (t1) (d−1) Band range (s) 20 6.05 2.31 37.54 ±1.05 30 6.25 5.21 32.60 ±1.70 40 9.25 5.70 17.33 ±5 45 2.93 13.12 20 ±8 Modified 45 16.22 3.15 10.96 ±2.5 Additional fit was performed for largest eluted activity (1,665 MBq) to demonstrate that data could be more precisely fitted without 2 days’ worth of generator results.
