Optimization of acquisition parameters for the detection of secondary breast lesions applying temporal contrast enhanced digital mammography

摘要

Temporal contrast-enhanced digital mammography (CEDM) is an image technique that might improve detection of secondary breast lesions (multicentric and multifocal breast cancer) as an alternative to breast MRI. This work refers to its implementation using a commercial mammography unit and reports preliminary clinical results. Image acquisition parameters (beam quality and other radiological settings) were optimized to maximize iodine contrast to noise ratio in subtracted images acquired under single- and dual-energy techniques, limited to 2.4 mGy average glandular dose. An analytical formalism is presented to assess how optimization results are affected by breast thickness. Weighting factors were determined using a novel method, and a single value was proposed for each pair of beam qualities, regardless of breast thickness or dose distribution. Twenty-six patients with suspected multicentric breast cancer have been studied, applying results from this formalism, with temporal CEDM and MRI followed by biopsy of suspicious lesions. Preliminary results show that both procedures have a similar sensitivity to detect malignancy (90% and 89%). Additionally, the effect of compression on iodine uptake has been investigated, observing a significant increase in iodine when compression force was reduced from 40 N to 20 N (3.6 mg/cm~2 vs. 1.6 mg/cm~2, p=0.0004).