DIEP-MDS for Risk Stratification of Flap Vascular Compromise and Failure in Breast Reconstruction

Inclusion Criteria

1. Female participants aged 18 to 80 years.
2. Reference CTA cohort: adult women without breast cancer or reconstructive surgery who had available abdominal CTA imaging of sufficient quality, obtained for reasons unrelated to breast reconstruction.
3. Internal surgical cohort: patients who underwent DIEP flap breast reconstruction at the coordinating center, with available preoperative abdominal CTA imaging and traceable perioperative and outcome data.
4. External multicenter surgical cohort: patients who underwent DIEP flap breast reconstruction at participating external centers, with available preoperative abdominal CTA imaging and traceable perioperative and outcome data.
5. For the internal and external surgical cohorts, operative records must clearly document whether a single-pedicle strategy or dual-pedicle strategy was used.

Exclusion Criteria

1. Prior abdominal flap harvest, abdominoplasty, major lower abdominal wall reconstruction, or extensive abdominal wall trauma or scarring expected to substantially alter DIEP perforator morphology.
2. Poor CTA image quality or insufficient image coverage for standardized assessment of key anatomic features relevant to DIEP perforator morphology.
3. Missing key clinical, imaging, operative, or outcome data required for the study analysis.
4. Non-DIEP abdominal flap procedures, combined flap procedures, or procedures in which DIEP flap anatomy, pedicle strategy, flap-related vascular compromise status, unplanned surgical takeback status, or flap failure status cannot be clearly determined.
5. For the reference CTA cohort, any history of breast reconstruction or abdominal wall procedures expected to substantially alter DIEP perforator morphology.