Article Figures & Data
Figures
- FIGURE 1.
Cross calibration against dose calibrator (A) is needed to convert count readings from thyroid probe (B) and well counter (C) to units of activity (kBq or μCi) for blood samples.
- FIGURE 2.
Steps for calculating SKA-M. (A) Single patient’s blood sample is used to scale population average blood activity curve and estimate patient’s blood activity curve, Cp(t). Tumor uptake curve, A(t), is measured during PET acquisition between 30 and 60 min after injection in 12 frames. Two time curves, Cp(t) and A(t), are used to generate plot shown in B with data points corresponding to each PET frame. Slope of line fitted to these 12 points is SKA-M parameter. (C) Relationship between blood scale factor and SKA-M parameter.
- FIGURE 3.
Sample calibration curve obtained for well counter in range of typical blood activities for SKA-M.
- FIGURE 4.
Errors in blood activity measurements using ProbePoint (A) or WellPoint techniques (B) in 35 patients. Errors are relative to WellCurve technique, which is assumed to be ground truth. Accuracy of blood sampling techniques in A and B is reflected by accuracy of SKA-M in C and D, respectively. Red lines are average values for each plot.
- FIGURE 5.
Pipette volume precision estimated for 10 patients, with each patient represented by a different symbol. (B) Absolute blood activity in 10 patients having 3–6 blood samples. Letters A to J correspond to the 10 patients. Numbers after each letter are sample numbers for each patient. (B) Percentage difference of each blood sample from mean for patient.
- FIGURE 6.
Micropipette accuracy and precision of 5 nuclear medicine technologists in measuring 0.9 mL of water.
