Optimum emission time in deep-inspiration breath-hold PET-CT: a preliminary result.
OBJECTIVE
The purpose of this study was to investigate optimum emission time of deep inspiration breath-hold (DIBH) positron emission tomography-computed tomography (PET-CT).


METHODS
We collected 15 PET-CT data sets by adding data of every 10 s and acquisition time ranging from 10 s (1 x 10 s acquisition) to 150 s (15 x 10 s acquisition) for both of DIBH mode and free-breathing condition (continuous mode) in phantom study. The coefficient of variation (CV) of radioactivity concentration was compared to determine optimum emission time of PET-CT. We also compared images of DIBH mode and continuous mode to clarify the influence of diaphragmatic movement in clinical setting.


RESULTS
The mean +/- SD of CV in DIBH mode was 1236.3 +/- 323.1. When compared with the CV at 120 s, the relative error of CV is within 10% at 110 s (0.204), 15% at 100 s (0.212), and 20% at 90 s (0.222), respectively. Optimum emission time greater than 90 s is required to obtain clinically available images in DIBH mode. In the clinical setting, the SUV of the lung base and measurements of uptake show little influence by respiration on DIBH PET-CT.


CONCLUSIONS
Optimum emission time of DIBH technique greater than 90 s acquisition is preferable for clinical use.
Miyashita
Koichi
K
Department of Radiology, Yokohama City University Graduate School of Medicine, Kanazawa-ku, Japan.
Tateishi
Ukihide
U
Nishiyama
Yuji
Y
Minamimoto
Ryogo
R
Shizukuishi
Kazuya
K
Inoue
Tomio
T
D000328:Adult; D005260:Female; D006801:Humans; D001239:Inhalation; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods*