Comparison of technetium-99m pyrophosphate and technetium-99m DTPA aerosols for SPECT ventilation lung imaging.
Although [99mTc] diethylenetriaminepentaacetic acid (DTPA) is currently the most widely used radioaerosol, rapid alveolar clearance limits its usefulness for single photon emission computed tomography (SPECT) ventilation lung imaging. Previous research has shown that [99mTc]phosphate compounds have high alveolar deposition and slow clearance and thus provide suitable aerosols for pulmonary ventilation studies. We have compared the pulmonary retention and blood levels of [99mTc]pyrophosphate (PYP) and [99mTc]DTPA in eight normal nonsmoking male volunteers. These two radioaerosols have comparable pulmonary deposition. Technetium-99m PYP, however, has a much slower pulmonary clearance which allows sufficient time (20 or more minutes) for SPECT data acquisition using a single-headed rotating gamma camera. While the radiation absorbed dose to the lungs for [99mTc]PYP (0.31 rad/mCi) is greater than for [99mTc]DTPA (0.11 rad/mCi), it is at a clinically acceptable and safe level.
Isitman
A T
AT
Department of Radiology, Medical College of Wisconsin, Milwaukee.
Collier
B D
BD
Palmer
D W
DW
Trembath
L
L
Krasnow
A Z
AZ
Rao
S A
SA
Hellman
R S
RS
Hoffmann
R G
RG
Peck
D C
DC
Dellis
C J
CJ
D000280:Administration, Inhalation; D000328:Adult; D000336:Aerosols; D011756:Diphosphates / Q000008:administration & dosage; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging*; D008297:Male; D009942:Organometallic Compounds / Q000008:administration & dosage; D004369:Pentetic Acid / Q000008:administration & dosage; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging; D013667:Technetium / Q000008:administration & dosage; D016284:Technetium Tc 99m Pentetate; D016698:Technetium Tc 99m Pyrophosphate; D014055:Tomography, Emission-Computed
D000336:Aerosols; D011756:Diphosphates; D009942:Organometallic Compounds; D016698:Technetium Tc 99m Pyrophosphate; D013667:Technetium; D004369:Pentetic Acid; D016284:Technetium Tc 99m Pentetate