Symbol Definitions
| Symbol | Definition |
|---|---|
| T | True coincidence count rate (kcps) |
| S | Scattered coincidence count rate (kcps) |
| R | Random coincidence count rate (kcps) |
| P | Prompt coincidence count rate, defined as P = T + S + R |
| D | Delayed coincidence rate, defined as D = R |
| σs | Scatter fraction, defined as σs = S/(T + S) |
| SP | Single-photon count rate (Mcps) |
| NEC | Noise equivalent count rate (kcps) |
| A | Activity concentration (kBq/mL) in phantom thoracic chamber |
| d | Mean tracer activity in patient at acquisition start (MBq) |
| c | Mean activity per weight d/w |
| ĉ | Mean activity in patient normalized for patient morphology |
| α | Proportionality constant in SP = α · A (Eq. 1) |
| β and β̂ | Proportionality constant in SP = β · c and SP = β · ĉ (Eqs. 8 and 9) |
| w | Patient weight (kg) |
| h | Patient height (m) |
| BMI | Body mass index, defined as BMI = w/h2 |