Initial in vivo quantification of Tc-99m Sestamibi uptake as a function of tissue type in healthy breasts using dedicated breast SPECT-CT

A pilot study is underway to quantify in vivo the uptake and distribution of tc-99m sestamibi in subjects without previous history of breast cancer using a dedicated spect-ct breast imaging system. subjects undergoing diagnostic parathyroid imaging studies were consented and imaged as part of this irb-approved breast imaging study. for each of the seven subjects,one randomly selected breast was imaged prone-pendant using the dedicated,compact breast spect-ct system underneath the shielded patient support. iteratively reconstructed and attenuation and/or scatter corrected images were coregistered; ct images were segmented into glandular and fatty tissue by three different methods; the average concentration of sestamibi was determined from the spect data using the ct-based segmentation and previously established quantification techniques. very minor differences between the segmentation methods were observed,and the results indicate an average image-based in vivo sestamibi concentration of 0.10 ± 0.16 μci/ml with no preferential uptake by glandular or fatty tissues. © 2012 steve d. mann et al.