Quantitative lung perfusion scintigraphy and detection of intrapulmonary shunt in liver cirrhosis

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

“…The results of this study showed that the diagnostic values are slightly higher than those provided by studies from other countries and that 99m Tc-MAA scintigraphy provides diagnostic indexes with excellent reproducibility degree, especially considering the brain uptake index. 99m Tc-MAA scintigraphy is a simple and safe test, with sensitivity and specificity similar to those Doppler echocardiography [12]. Moreover, it has the advantage of quantifying the shunt magnitude [4], which seems to be important in assessing the prognosis of these patients [10].…”

“…The kappa concordance index is used when the result is given categorically (positive or negative IPVD), and the result is expressed with values between 0 and 1. If the result is greater than 0.80, the agreement is considered excellent [12]. The intra-class correlation coefficient is used to assess agreement when quantitative measures are assessed, and the result is also expressed by values between 0 and 1.…”

Pulmonary blood transit time and impaired arterial oxygenation in patients with chronic liver disease

“…2,3,[8][9][10] IPVD is usually assessed by contrast-enhanced echocardiography (CEE) using manually agitated saline that contains air microbubbles, 4,5,9,11,12 or by intravenous injection of 99m Tc-macroaggregated albumin (MAA). 6,11,13 The latter method is employed for determination of the amount of blood shunted through the dilated intrapulmonary vessels, but a high sensitivity is not achievable. On the other hand, the diagnostic capability of CEE using agitated saline is limited to detecting the existence of intrapulmonary vasodilatation (vessels over 20 µm in diameter).…”

Reply to ‘Accurate measurement of the normality values of macroaggregated albumin lung perfusion scan in hepatopulmonary syndrome’

“…In the literature, the time between intravenous injection of 99m Tc-MAA and the acquisition of images has varied from acquisition immediately after injection of the radiopharmaceutical to 60 min [1][2][3]. The passage of 99m Tc-MAA from pulmonary capillaries to the systemic circulation is not immediate in intrapulmonary vascular dilatation, and so we believe that the interval between injection of 99m Tc-MAA and the image acquisition is important to increase the test sensitivity.…”