Evaluation of normality and reproducibility parameters of scintigraphy with 99mTc-MAA in the diagnosis of intrapulmonary vascular dilatations

Abstract

The normality values were slightly higher than those reported in studies from other countries. The demographic characteristics of the Brazilian population, the small number of patients or different methodologies can be the causes of such differences. (99m)Tc-MAA scintigraphy showed excellent reproducibility.

Comparison of estimated human dose of 68Ga-MAA with 99mTc-MAA based on rat data

“…As demonstrated in Fig. 2c, after more purification, the lung uptake will rise from 89 % to 97 % of the %ID/g, which is in accordance with the previous studies on 68 Ga-MAA [7,17]. Fig.…”

“…3, our dosimetry data reveal that 68 Ga-MAA even after 1 time centrifuge was much safer than 99m Tc-MAA in terms of dose delivery to the other organs except for lung and total body dose. There is another advantage of 68 Ga-MAA compared to the 99m Tc-MAA in terms of lung uptakes were other studies show that the lung uptake for 99m Tc was about 87 and 79 % of %ID/g at 2 and 4 h post injection, respectively; this value for 68 Ga-MAA is more than 90 % [7,17]. As represented in Fig.…”

“…MAA in labeling with 99m Tc, 99m Tc-MAA, has been introduced for different use such as perfusion lung imaging to assess the presence of pulmonary emboli, radionuclide venography to identify lower extremity venous thrombosis and assessment of peritoneovenous shunt patency [7,8]. Due to the special characteristics of 68 Ga and MAA, it seems 68 Ga-MAA complex can be a potential PET imaging agent [9].…”

Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy

“…The application of pulmonary perfusion scintigraphy to evaluate lung function and the development of lung vessels has been documented in many studies. [ 8 , 16 – 18 ] It is widely available for clinical practice and fundamental research with unique advantages. First, lung perfusion scintigraphy was hardly affected by the tracer injection pressure.…”

“…The Tc-99m-MAA remains trapped in the pulmonary capillary bed in a natural way, and radioactivity is distributed in the lung segments in proportion to the relative blood flow. [ 16 ] Secondly, this method provides an alternative to the quantitative and hemi-quantitative methods to evaluate the physiology information regarding pulmonary microcirculation with relatively higher sensitivity, specificity, and accuracy. Moreover, it was easy to perform, and the results were easy to interpret.…”