Quantification of technetium-99m hexamethylpropylene amine oxime brain uptake in routine clinical practice using calibrated point sources as an external standard: phantom and human studies.
Quantitative methods for calculation of regional cerebral blood flow with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) have been proposed. These methods are very labour intensive and therefore are not useful in routine clinical practice. We describe a simple alternative method, using calibrated point sources as a scaling factor, whereby the tomographic slices are displayed as regional 99mTc-HMPAO brain uptake per cm3 brain tissue in 10(-6) of the injected lipophilic dose. The method was validated on Jaszczak and Hoffman phantoms using a three-detector system with HR parallel and HR fan-beam collimators. Under the optimal conditions described in this paper, the measured to real activity ratio was 1.00 (SD = 0.06). The reproducibility of the cerebellar uptake in a group of ten normal volunteers and five patients was studied. Intra-individually a mean deviation of 12.6% was observed for the total group. For those persons with a heart rate difference of less than 5 units between the two studies, a mean deviation of 7.2% was obtained. Quantitative 99mTc-HMPAO brain uptake images can be useful for longitudinal studies, especially for follow-up, activation and pharmacological studies.
Dobbeleir
A
A
Nuclear Medicine Department, Middelheim Hospital, Antwerp, Belgium.
Dierckx
R
R
D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D008961:Models, Structural; D015609:Organotechnetium Compounds / Q000493:pharmacokinetics*; D010091:Oximes / Q000493:pharmacokinetics*; D011877:Radionuclide Imaging; D012039:Regional Blood Flow; D019690:Technetium Tc 99m Exametazime
D015609:Organotechnetium Compounds; D010091:Oximes; D019690:Technetium Tc 99m Exametazime