Technetium-99m-HMPAO- It's role in assessing peripheral perfusion

Full text: Excellent limb uptake of 99mTc-hexamethyl-propyleneamine oxime (99mTc-HMPAO), was observed in a patient undergoing exercise as part of the assessment for syncope. Consequent to this we employed exercise followed by injection of 99mTc-HMPAO to assess arm and finger perfusion in a patient with an AV dialysis shunt. The first patient was bicycle-exercised to a submaximal level of 75 watts before injection of 740 MBq of 99mTc-HMPAO. The study was then repeated 14 days later at rest. Relative uptake in the leg on the initial (exercise) study was 39% and on the rest study was 19% of the total body counts. The exercise study particularly outlined the active muscle groups. The second patient presented with right finger coolness and parasthesia following a brachial A-V fistula. The study showed relative finger uptake at 10 minutes post-injection of R:L 1: 1. 8, and R:L palmar uptake of 1: 1.3. The initial perfusion index for the fingers over the first 60 sec was approximately 1:10 (R:L) These two preliminary cases suggest a role for 99mTc-HMPAO in the assessment of peripheral perfusion, with uptake being influenced by both exercise and the muscle volume in the region studied