Detection of Pulmonary Embolism with Gallium-68 Macroaggregated Albumin Perfusion PET/CT: An Experimental Study in Rabbits

Abstract

This study was designed to evaluate the accuracy of detecting pulmonary embolism (PE) using the Technegas SPECT/CT combined with 68Ga PET/CT in a rabbit model. One hour after artificial PE (n = 6) and sham (n = 6) models were created, Technegas SPECT/CT ventilation and 68Ga-MAA PET/CT perfusion scan (V/Q scan) were performed. Ventilation imaging was performed first on all cases. Technegas SPECT/CT and 68Ga-MAA PET/CT images were evaluated by a nuclear medicine physician who recorded the presence, number, and location of PE on a per-lobe basis. The sensitivity, specificity, and accuracy of Technegas SPECT/CT and 68Ga-MAA PET/CT for detecting PE were calculated using a histopathological evaluation as a reference standard. A total of 60 lung lobes were evaluated in 12 rabbits, and PE was detected in 20 lobes in V/Q scans and histopathological analysis. The overall sensitivity, specificity, and accuracy were 100%, 100%, and 100%, respectively, for both the Technegas SPECT/CT and 68Ga-MAA PET/CT V/Q scans. Technegas/68Ga-MAA V/Q scans have good sensitivity, specificity, and accuracy in the detection of PE in this animal model study.

Good practices for Ga-68 radiopharmaceutical production: an important correction

“…68 Ga-macroaggregated albumin is stated to be a potential radiopharmaceutical in lung perfusion studies in preclinical and clinical studies (Gültekin et al 2020 ; Ament et al 2013 ). 68 Ga-macroaggregated albumin is not used in myocardial perfusion studies.…”

Microfluidic Fabrication of Silica Microspheres Infused with Positron Emission Tomography Imaging Agents

“…Ga-68 has been used as a radionuclide since the 1960s; it is usually chelated onto DOTATATE or DOTATOC molecules for imaging and differentiating neuroendocrine tumors, which have upregulated somatostatin receptors . Ga-68 has also been used to radiolabel MAA particles, similar to Tc-99m labeling. − While these particles will still have the disadvantages associated with being MAA particles, they improve upon the Tc-99m MAA particles by virtue of being PET radiotracers and overcoming supply issues often associated with the Tc-99m parent element, molybdenum.…”

Chemical and Physical Characterisation of Macroaggregated Human Serum Albumin: Strength and Specificity of Bonds with 99mTc and 68Ga

“…Usually a prewash of MAA in commercial kit resulted in a higher gallium labelling efficacy, likely due to the removal of the free HSA contained therein as excipient [13].…”