The anatomical location and quantity of the fibular flap perforators vary among patients. Therefore, using medical imaging to assist in precise intraoperative localization of these perforators can reduce surgical time and complications. Computed tomography angiography (CTA) can provide high-resolution medical images and even reconstruct three-dimensional virtual models of bones and perforating vascular anatomy. However, these images are still confined to screens and cannot be directly displayed in the surgical field, relying solely on the surgeon's mental alignment.
Hence, this study introduces augmented reality (AR) technology, employing computer vision alignment to overlay virtual images onto the surgical field, aiding surgeons in a more intuitive interpretation of medical images. Initially, three-dimensional virtual anatomical images are reconstructed, and the relative position between targeting and virtual anatomical images was established with Unity. Finally, QR codes are affixed to the patient's body as references for the AR coordinate system. The software functionalities used in preparing the AR scene are all free of charge.
During surgery, we capture the surgical field using a webcam, allowing the virtual anatomical model of bones and perforating branches to overlay onto the patient's body on the computer screen. This assists in the precise localization of the perforating branches and planning the flap skin paddle. To evaluate the accuracy of the virtual image alignment, this study utilizes handheld ultrasound to identify the actual position of the perforating branches.
In summary, this research proposes a low-cost augmented reality workflow for fibular flap harvesting and validates its feasibility. This technology has the potential for application in other flap surgeries.