Background
The medial sural artery perforator flap has gained popularity for its expanded use. Image-based preoperative planning is usually crucial for flap reconstruction. Computed tomographic angiography has been used as a non-invasive evaluation of vascular anatomy, and it may provide comprehensive information for flap design. This study aimed to investigate the correlation between angiographic findings and clinical outcome in medial sural artery perforator flap reconstruction.
Methods
Patients scheduled to receive medial sural artery perforator flap reconstruction between 2016 and 2020 were recruited. Those who did not receive preoperative computed tomographic angiography were excluded. All the preoperative images were interpreted by a single radiologist. Computed tomographic angiography and operative findings were recorded. Medial sural artery branching patterns were analyzed.
Results
Four types of arterial branching patterns were identified by the angiographic findings, which were based on the vascularity to the medial gastrocnemius muscle. Type I (18.8%) exhibited a single main trunk with or without tiny branches around tibial plateau. Type II (64.0%) presented as a bifurcation above tibial plateau or dual main trunks. Type III (10.4%) consisted of multiple branches emerging near tibial plateau. Type IV (4.3%) presented with a tiny or absent medial sural artery. Available perforators were identified in all type I and type II, a back-up flap was sometimes required in type III, and no available perforators ever existed in type IV. The average intramuscular of the pedicle was 1.03 ± 0.46 centimeters depth. There was no abrupt decrease of caliber size at the level of bifurcation above tibial plateau. The branching patterns may be different in bilateral lower limbs.
Conclusion
Computed tomographic angiography is a useful non-invasive tool in preoperative vascular and soft tissue assessment. Type II branch pattern is the best scenario for planning medial sural artery perforator flap, due to existence of sizable perforators and viability of the medial gastrocnemius muscle following harvest. Computed tomographic angiography of bilateral lower extremities may help surgeons figure out the favorable vascular anatomy in advance, and have a dependable preoperative plan for medial sural artery perforator flap harvest.