Assessment of breast compression direction based on calcification location in prone digital breast tomosynthesis-guided vacuum-assisted breast biopsy: a phantom study

Abstract Background Mammography-guided vacuum-assisted biopsy (MMG-VAB) is widely used as a minimally invasive, high-precision diagnostic method for non-palpable microcalcification breast lesions, particularly as an alternative to surgical excision. Mammography-guided vacuum-assisted biopsy includes both conventional stereotactic-guided vacuum-assisted biopsy (ST-VAB), using stereotactic angled image pairs for 2D triangulated imaging, and the newer digital breast tomosynthesis-guided vacuum-assisted biopsy (DBT-VAB), which uses 3D images synthesized from multiple tomogram layers. Digital breast tomosynthesis-guided vacuum-assisted biopsy using a prone position enables more accurate coordinate determination and shorter procedure times than stereotactic-guided vacuum-assisted biopsy. However, no clear criteria currently exist to derive the optimal compression direction, considering the lesion’s anatomical location and the device’s physical constraints. This study aimed to clarify criteria for selecting the compression direction to enable reliable tissue sampling for calcifications across different breast regions. Methods We used a variable proprietary breast phantom with pre-determined simulated calcifications placed in all four breast quadrants. Compression and imaging were performed from eight directions. We evaluated the distances from the needle tip to the support platform, the tissue sampling port to the target center, and the relationship with the compression paddle, and checked if warning messages indicating tissue sampling difficulty were displayed. Results There were significant differences between compression direction and alert occurrence across all regions ( p < 0.001). Compression direction also determines the biopsy needle trajectory. Compression along the target’s diagonal from the opposite quadrant increased the risk of target deviation or detector damage. Conversely, compression from the opposite direction on the same diagonal (closest to the calcification) risked exposing the sampling port above the skin level, potentially causing aspiration failure or skin contusion. Conclusions In prone DBT-VAB, the device-generated alerts serve as a proxy for technical difficulty rather than as predictors for clinical outcome. However, considering avoiding specific compression directions that are more likely to lead to errors - from 180° across and the direction immediately adjacent to the calcification area - is recommended to help manage the physical constraints of the device and ensure reliable diagnostic capability.