Pulmonary (V/Q) Imaging

Article Figures & Data

Instrumentation Imaging Parameters
Camera type	Large field of view (single or multidetector)
Energy peaks	140 keV (^99mTc) 81 keV (¹³³Xe) 190 keV (^81mKrypton)
Energy window	20%
Collimator	Low-energy all-purpose or high-resolution
Matrix	128 × 128 (ventilation/SPECT) 256 × 256 (planar)
SPECT
Orbit	360° (non-circular preferred)
Number of projections	60—single head (6°) 120—dual head (3°)
Time/projection	10 seconds/projection (aerosol) 20–30 seconds/projection (perfusion)
Acquisition type	Step-and-shoot or continuous

Radiopharmaceuticals—Gas
Identity	Dose	Route of administration
¹³³Xe gas	100 MBq (5 mCi) Range: 200–750 MBq (5–20 mCi) Pediatric dose: 10–12 MBq/kg (0.3 mCi/Kg)—minimum dose, 100–120 MBq (3 mCi)	Continuous inhalation
^81mKrypton (not available in the United States)	40–400 MBq (1–10 mCi)	Continuous inhalation

Radiopharmaceutical—Aerosol
Identity	Dose	Route of administration
^99mTc-diethylenetriamine pentaacetic acid (DTPA) aerosol	900 MBq (25 mCi) Range: 900–1,300 MBq (25–35 mCi)	Continuous inhalation
^99mTc-sulfur colloid aerosol	900 MBq (25 mCi) Range: 900–1,300 MBq (25–35 mCi)	Continuous inhalation

Radiopharmaceutical—Perfusion
Identity	Dose	Route of administration
^99mTc-macroaggregated albumin (MAA)	40 mBq (1 mCi) Range: 40–150 MBq (1–4 mCi) 200,000–700,000 particles Pediatric dose: 1.11 MBq/kg (0.03 mCi/kg) 2.59 MBq/kg (0.07 mCi/kg) if ^99mTc aerosol study performed Minimum activity: 14.8 MBq (0.4 mCi)	Intravenous