Pediatric Patients - 50k to 75k
Pulmonary Hypertension = 100k to 150k
Patient with 1 lung = 150k to 200k
Normal Lung scan = 200k to 700k.
Heck and Duley1 evaluated dog lungs and determined that 60 particles per gm of lung was adequate. Adult human lungs may average 1000 gm, which translates to 60k particles per perfusion dose. The authors also suggested that the upper dose limit should be set to 250k particles. Beyond this amount toxic effects may occur.
1 - Heck LL, Duley JW. Statistical considerations in lung imaging with Tc-99m albumin particles. Radiology. 1974