Evaluating the Role of Digital Subtraction Angiography in Traumatic Lower Extremity Flap Reconstruction: A Comparative Analysis With CT Angiography.

[BACKGROUND] Despite its high sensitivity and specificity, CTA can yield inconclusive or inaccurate results due to technical limitations such as metallic streak artifacts or inadequate opacification of arteries. On the other hand, digital subtraction angiography (DSA), a fluoroscopic technique used extensively in interventional radiology for visualizing blood vessels, stands as a gold standard for the assessment of arterial injuries, offering high-resolution and dynamic imaging.

[METHODS] Patients undergoing lower extremity reconstruction with a free flap at a Level 1 trauma center between 2015 and 2022 were retrospectively queried. Demographic data, details of arterial injuries assessed by CTA/DSA, flap and wound details, complications, and ambulatory outcomes were recorded. The study data were assessed and presented qualitatively.

[RESULTS] A total of 175 patients underwent microsurgical lower extremity reconstruction from 2015 to 2023, 98 (56.0%) of whom had CTA, and 14 (8.0%) underwent DSA preoperatively. The mean patient age was 47.1 ± 15.6 years, ranging from 21 to 68 years, with 10 (71.4%) males and four (28.6%) females. The most common indications for DSA were inconclusive CTA results of vessel runoff status (n = 6), evaluation of clinically suspected vascular injury not clearly delineated by CTA (n = 3), and artifact/streak due to orthopedic hardware (n = 2). DSA in six of the 14 cases revealed discrepancies with initial CTA findings, providing clarification on the location and extent of vascular injury preoperatively. Four of these patients experienced a change in surgical plan following formal angiography. There was no significant difference in postoperative flap complications (p = 0.189) or ambulation status (p = 0.074) between the DSA and CTA cohorts.

[CONCLUSION] DSA effectively overcomes limitations encountered with CTA, such as issues related to hardware interference. In select patients where CTA limitations are significant, DSA might offer improved outcomes, highlighting the need for further research to validate these preliminary findings and better define the contexts in which DSA could be more beneficial.