Convolutional neural networks for wound detection: the role of artificial intelligence in wound care.

OBJECTIVE: Telemedicine is an essential support system for clinical settings outside the hospital. Recently, the importance of the model for assessment of telemedicine (MAST) has been emphasised. The development of an eHealth-supported wound assessment system using artificial intelligence is awaited. This study explored whether or not wound segmentation of a diabetic foot ulcer (DFU) and a venous leg ulcer (VLU) by a convolutional neural network (CNN) was possible after being educated using sacral pressure ulcer (PU) data sets, and which CNN architecture was superior at segmentation. METHODS: CNNs with different algorithms and architectures were prepared. The four architectures were SegNet, LinkNet, U-Net and U-Net with the VGG16 Encoder Pre-Trained on ImageNet (Unet_VGG16). Each CNN learned the supervised data of sacral pressure ulcers (PUs). RESULTS: Among the four architectures, the best results were obtained with U-Net. U-Net demonstrated the second-highest accuracy in terms of the area under the curve (0.997) and a high specificity (0.943) and sensitivity (0.993), with the highest values obtained with Unet_VGG16. U-Net was also considered to be the most practical architecture and superior to the others in that the segmentation speed was faster than that of Unet_VGG16. CONCLUSION: The U-Net CNN constructed using appropriately supervised data was capable of segmentation with high accuracy. These findings suggest that eHealth wound assessment using CNNs will be of practical use in the future.

Reconstruction of Complex Groin Defects After Sarcoma Resection.

BACKGROUND: Complex groin defects after sarcoma resection require reconstruction of multiple vital structures that can include the major vessels, the overlying skin, the abdominal wall, and the hip joint. We investigated the feasibility of limb preservation after complex groin reconstruction. METHODS: The subjects were 12 consecutive patients who underwent complex groin reconstruction after sarcoma resection. In all patients, the defect included a major artery (external iliac or femoral) and overlying skin. The defect included the abdominal wall in 5 patients and the hip joint in 2. Arterial reconstruction was performed with an autologous vein graft in 9 patients and with an expanded polytetrafluoroethylene graft in 3. Soft-tissue coverage was performed with a pedicled rectus abdominis musculocutaneous flap in 7 patients, a free latissimus dorsi musculocutaneous flap in three, and a free anterolateral thigh flap in 2. RESULTS: Postoperative complications occurred in 7 patients (58.3%). Limb salvage was possible in 8 patients (66.7%) with 39 months' median follow-up. Two patients required amputation because of wound problems, and 2 required amputation because of local recurrence of the tumor. CONCLUSIONS: Limb salvage is possible even after extensive resection of groin sarcoma, although the rate of postoperative wound complications is substantial. Proper selection of the arterial conduit and the soft-tissue flap, depending on the components of the defect, are mandatory for successful reconstruction.

Combined Use of the Latissimus Dorsi Musculocutaneous Flap and the Anterolateral Thigh Flap to Reconstruct an Extensive Shoulder Defect in an NF-1 Patient.

Soft tissue coverage after the resection of a large malignant peripheral neural sheath tumor (MPNST) is a challenge. We report the successful reconstruction of an extensive shoulder defect after MPNST resection in a patient with a type 1 neurofibromatosis with a novel combination of flaps. A 70-year-old man with type 1 neurofibromatosis presented with a recurrent MPNST on his right shoulder. He underwent a wide excision of the tumor, which resulted in a huge soft tissue defect around the shoulder joint. The resultant defect was reconstructed with a pedicled latissimus dorsi musculocutaneous flap and a free anterolateral thigh flap. The flaps survived, and the wounds healed uneventfully. His affected arm was useful. The combination of a pedicled latissimus dorsi musculocutaneous flap and a free anterolateral thigh flap is a versatile option for the reconstruction of an extensive shoulder defect.

Drug-Induced Atrial Fibrillation Complicates the Results of Flap Surgery in a Rat Model.

The relationship between atrial fibrillation (AF) and flap survival has not been fully characterized. Therefore, the goal of this study was to investigate the effect of AF on survival areas of pedicled flap and survival rates of free flap in an experimental rat AF model. An aconitine-induced rat AF model was established without intubation anesthesia. Survival areas of the pedicled rectangular epigastric flap were compared between AF rats (n = 7) and control rats (n = 7), and survival rates of the free epigastric flap were compared between AF rats (n = 10) and control rats (n = 10). Animals that died during the study or in which AF was not induced were excluded from study. A total of 64 rats were assessed in this study. Atrial fibrillation was induced with a success rate of 77.8% (21/27) throughout the study. Pedicled flap survival area was significantly higher in controls (75.1 ± 9.0%; n = 7) than that in AF animals (55.7 ± 13.0%; n = 7) (P < 0.01, nonpaired Student t test). Free flap survival rates were 80% in controls and 40% in AF animals (P = 0.07, χ² test). This is the first study to develop an aconitine-induced model of AF in rats. Atrial fibrillation has a detrimental effect on survival areas of the pedicled flap and survival rates of the free flap.

Free flow-through anterolateral thigh flap for complex knee defect including the popliteal artery.

Reconstruction of complex knee defects including the popliteal artery presents a challenging problem in reconstructive microsurgery. Reconstruction of the popliteal artery and soft-tissue coverage should be performed simultaneously for limb salvage. We present the one-stage reconstruction of a complex knee defect including the popliteal artery using a free flow-through anterolateral thigh (ALT) flap as a bypass flap in two patients with sarcomas. In both patients, the popliteal artery and vein were reconstructed using branches of the lateral circumflex femoral arterial system. The flaps survived without vascular compromise and the limbs were preserved successfully. Free flow-through ALT flap enables simultaneous leg revascularization and soft-tissue coverage with a single free flap. The lateral circumflex femoral arterial system has many branches with large diameters, making it suitable for reconstruction of multiple infrapopliteal arteries.

One-stage reconstruction of a tracheal defect with a free radial forearm flap and free costal cartilage grafts.

Reconstructing the trachea is challenging because of its multilayer structure and airway function; multiple procedures are often required. We report a case of one-stage reconstruction for a tracheal defect. The surgery was performed with a free radial forearm flap and free costal cartilage grafts. Air leakage occurred postoperatively but healed without additional surgery. The reconstructed trachea has retained its shape, diameter and airway function for 14 months despite the patient's history of radiotherapy. This one-stage procedure with well-vascularised tissue was successfully used to reconstruct a stable, well-functioning trachea.