Preoperative Vascular Imaging in Lower Extremity Free Flap Reconstruction: Comparison Between Imaging Modalities

Area of Science:

• Vascular Surgery
• Reconstructive Surgery
• Medical Imaging

Background:

• Successful lower extremity free tissue transfer relies on adequate vascular anatomy and perfusion.
• Computed tomography angiography (CTA) and conventional angiography are key imaging tools, offering detailed visualization and flow assessment.
• A standardized algorithm for preoperative imaging in lower extremity free flap reconstruction is currently lacking.

Purpose of the Study:

• To evaluate the utilization and outcomes of preoperative imaging modalities (CTA and angiography) for lower extremity free flap reconstruction.
• To assess complication rates associated with CTA and angiography in this patient population.
• To propose an institutional algorithm for guiding preoperative imaging decisions.

Main Methods:

• A retrospective review of 405 patients undergoing lower extremity free flap reconstruction between 2002 and 2020, identified via Current Procedural Terminology (CPT) codes.
• Analysis of electronic medical records for patient demographics, treatment details, imaging characteristics, and laboratory values.
• Outcomes assessed included imaging findings, related complications (e.g., contrast-induced nephropathy), and surgical results.

Main Results:

• 59% of patients received preoperative angiography, 10% CTA, and 7.2% both; 24% had no preoperative imaging.
• 40% of patients who underwent preoperative imaging demonstrated less than three-vessel runoff.
• Low complication rates were observed for both angiography and CTA, with no statistically significant risk factors identified for contrast-induced nephropathy (CIN).

Conclusions:

• Angiography and CTA are frequently used and safe imaging modalities for lower extremity free flap reconstruction.
• A significant proportion of patients (40%) exhibit suboptimal vessel runoff, highlighting the importance of thorough preoperative assessment.
• An institutional algorithm recommends angiography for patients with peripheral vascular disease, hardware, or trauma-related distal defects.