Anatomic symmetry of anterolateral thigh flap perforators: a computed tomography angiographic study

Abstract

Background: The anterolateral thigh flap is a workhorse reconstructive flap. Versatility in design is a key strength but perforator anatomy can be variable. Inability to locate perforators prompts consideration of contralateral thigh exploration. However, such exploration would be futile if the absence of perforators proves symmetrical. This study assesses the symmetry of anterolateral thigh flap vasculature using computed tomography angiography (CTA). Methods: A retrospective analysis of 20 bilateral thigh CTAs was performed. Each limb was assessed for number, course, location and size of perforators. Only vessels >0.5 mm in size at origin were included. Location was standardized between patients using perforator distance/thigh length ratio. Results were analysed using Wilcoxon signed-rank test. Results: In each thigh, the average number of perforators was 3.58 and average perforator distance/thigh length ratio was 0.358 AE 0.08. Between both limbs of the same patient, the mean difference in number of perforators was 0.55 (P = 0.002), and difference in average perforator size was 0.3 mm (P < 0.001). Average perforator location differed by a mean of 3% of thigh length (P < 0.001) between thighs. Conclusion: While average vessel size and location appear similar, there does not appear to be symmetry in the number of perforators. Surgical exploration of the contralateral thigh in an absence of perforators should be considered. In patients where abnormal anatomy is expected, mapping with CTA could be considered to reduce morbidity associated with unsuccessful surgical exploration and dissection.

Preoperative Computed Tomography Angiography for ALT Flaps Optimizes Design and Reduces Operative Time

“…We also identified a high rate of dominant perforator asymmetry between lower extremities in 32 patients (40.5%), a finding shared by several anatomic studies. 7 8 This is particularly important when there may be extreme differences in perforator anatomy between each side. There were 10 (12.7%) patients who entirely lacked visualized perforators on one side, and we theoretically avoided a poor operative course by seeing this on imaging.…”

“…Indeed, previous cadaveric and imaging studies have shown substantial intra- and interlimb perforator asymmetry within individual patients 7 8 and among individuals of different races and ethnicities. 9 10 11 Studies have revealed between one to four perforators emerge from the dbLFCA around the midpoint between the anterior superior iliac spine and the lateral patellar border.…”

Limitations of Computed Tomography Angiography in Preoperative Planning of Peroneus Brevis Rotational Flap

“…Identification of the ALT and MSAP vessels followed previously described techniques, [15][16][17]19 which were also applied for identifying PB vasculature. Axial two-dimensional images were scanned craniocaudally using our institution's standard CT image viewing software, Merge Radsuite (Merge Healthcare, Hartland, Wis.).…”

Reconstruction of Giant Defects Due to Electrical and Radiation Burns in the Lower Leg with Free Anterolateral Thigh Flaps

“…As described by Lu et al 13 , the perforator arteries of LCFA were located with a hand-held Doppler probe. The size and shape of the flap was planned based on the size and shape of the defect, and marked by more than 1 to 2 cm larger than the desired flap size.…”