Noise components on positron emission tomography images

Abstract

Noise components on PET images were studied. The results showed that the square of synthetic noise Δ² and the square of signal‐to‐noise ratio (N/Δ)² varied with the signal intensity N and the relationships were respectively expressed with: Δ²=0.0395N²+0.1427N+0.0025 (R²=0.9358) and (N/Δ)²=−1.13932N²+7.0185N−0.0746 (R²=0.9377). The synthetic noise on PET image may be categorized into three components. The first one varies directly as signal intensity, which depend on random coincidence; the second one varies directly as the square root of signal intensity, which depend on Poisson fluctuation; and the third one is independent of signal intensity.