Sonographic visibility of breast tissue markers: a tissue phantom comparison study

Rationale and objectives: Several commercially available breast tissue markers are promoted as being sonographically visible, allowing for subsequent targeting using ultrasound. The aim of this study was to compare the visibility of selected sonographic markers with the use of tissue phantoms. Materials and methods: Seven different markers were deployed into chicken and beef tissue phantoms, including a non-sonographically enhanced marker used as a baseline. Six participants assessed their sonographic visibility and needle targeted the markers using ultrasound. The sonographic visibility of each marker was graded, with scores corrected for accuracy following mammographic review of needle targeting position. Results: Only four of the six "ultrasound enhanced" markers demonstrated statistically significant greater visibility than the non-sonographically designed marker (P range < 0.001 to 0.04). Marker size (P < 0.001) and composition (P < 0.004) were shown to be contributing factors, with the composition of the BiomarC™ (Carbon Medical Technologies Inc, St Paul, MN, USA) demonstrating the highest conspicuity adjusted for length. Conclusion: There is significant variance in the visibility of breast tissue markers purported to be visible on ultrasound. Marker size, composition and possibly shape are contributory factors, with the utilisation of non-metallic components associated with improved conspicuity. Our study provides a basis for further determination of optimal marker qualities, and we recommend evaluation with a larger sample size and an "in-vivo" technique.