Accuracy in gamma camera measurements of point source velocities.
Mucociliary clearance is impaired in many diseases of the respiratory system. We have developed a method for measuring tracheal mucus velocity by the dynamic study of a single point source of radioactivity deposited in the trachea by cricothyroid injection. Preliminary results suggest that patients with airways disease have very low tracheal mucus velocities (<2 mm x min(-1)). The aim of this experiment was to explore the ability of current scintillation detection systems to track a single point as it moves in a dynamic study in small increments and at low velocity (movements of the order of 1 mm). Background noise was estimated to contribute an error in positioning of 0.16 mm (1 standard deviation). Overall errors in velocity were estimated at 0.2 mm x min(-1). This suggests that standard instrumentation in use in most nuclear medicine departments has the capacity to measure accurately velocities as low as 1 mm x min(-1).
Morgan
L C
LC
Department of Respiratory Medicine, Concord Repatriation General Hospital, NSW, Australia. lucy@rfu.crg.cs.nsw.gov.au
Pearson
M A
MA
Mackey
D W
DW
Rutland
J
J
de Iongh
R U
RU
Peters
M J
MJ
van der Wall
H
H
D015902:Gamma Cameras; D006801:Humans; D009079:Mucociliary Clearance; D011877:Radionuclide Imaging / Q000295:instrumentation / Q000379:methods; D015203:Reproducibility of Results; D012140:Respiratory Tract Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D014132:Trachea / Q000000981:diagnostic imaging