Augmented reality and dynamic infrared thermography for perforator mapping in the anterolateral thigh

Abstract

Dynamic infrared thermography (DIRT) has been used for the preoperative mapping of cutaneous perforators. This technique has shown a positive correlation with intraoperative findings. Our aim was to evaluate the accuracy of perforator mapping with DIRT and augmented reality using a portable projector. For this purpose, three volunteers had both of their anterolateral thighs assessed for the presence and location of cutaneous perforators using DIRT. The obtained image of these “hotspots” was projected back onto the thigh and the presence of Doppler signals within a 10-cm diameter from the midpoint between the lateral patella and the anterior superior iliac spine was assessed using a handheld Doppler device. Hotspots were identified in all six anterolateral thighs and were successfully projected onto the skin. The median number of perforators identified within the area of interest was 5 (range, 3–8) and the median time needed to identify them was 3.5 minutes (range, 3.3–4.0 minutes). Every hotspot was correlated to a Doppler sound signal. In conclusion, augmented reality can be a reliable method for transferring the location of perforators identified by DIRT onto the thigh, facilitating its assessment and yielding a reliable map of potential perforators for flap raising.

Thermal imaging for microvascular free tissue transfer monitoring: Feasibility study using a low cost, commercially available mobile phone imaging system

“…8 An additional study utilized a portable infrared thermography device to identify perforators of the anterolateral thighs of three volunteer subjects. 9 These support our hypothesis that this technology can be used to monitor free flaps in the postoperative period.…”

“…1,2,11,12 They have also been used to identify vascular perforators and flap integrity intraoperatively. [5][6][7][8][9] The application of thermal imaging technology or many other flap monitoring techniques involve the use of equipment with significant cost in the medical device marketplace.…”

Use of Augmented Reality in Reconstructive Microsurgery: A Systematic Review and Development of the Augmented Reality Microsurgery Score

“…In summary, the use of AR in reconstructive microsurgery was explored in five studies, consisting of 30 patients (►Table 2). [14][15][16]24,25 AR was evaluated in a bilateral lower limb lympho-venous anastomosis, 20 seven anterior lateral thigh flaps, 21,28 one latissimus dorsi flap, 25 one tensor facia lata flap, 25 15 deep inferior epigastric perforator (DIEP) flaps, 11,21 three medial sural artery perforator flaps, and three posterior tibial artery perforator flaps. 12 All of these studies demonstrated a level of evidence of four with the exception of the study from Nishimoto et al that showed a level of evidence of five (►Table 2).…”

“…To overcome these limitations, Cifuentes et al evaluated the use of projection-based AR whereby digital data are physically superimposed by means of projection onto the surface of the skin. 28 The authors combined the capabilities of a thermal camera and a portable projector to project a thermal map of anterolateral thigh perforators onto the surface of the skin on volunteers. This study identified an average of five perforators in the area of interest, which correlated 100% with hand-held Doppler findings.…”

“…This study identified an average of five perforators in the area of interest, which correlated 100% with hand-held Doppler findings. 28 The use of projector-based AR technology may reduce the need for hardware and improve the surgeon's experience. Similar projection-based technologies were used in other studies in this systematic review.…”