Irritated Subtype of Seborrheic Keratosis in the External Auditory Canal

vessel for microanastomosis, non-microsurgical methods are suggested, such as a composite graft, retroauricular pocket, or a temporoparietal fascia flap. A few reports of large composite grafts to the ear have been published. The survival rate of composite grafts is lower than that of replantation with microvascular anastomosis. The vessel status of amputees who have sustained a human bite injury is often not suitable for anastomosis. Moreover, the risk of wound infection is often increased, as in our case. A variety of adjunctive treatments, such as the administration of heparin, prostaglandin, leeches, and HBOT, have been introduced for patients who undergo a composite graft. However, these treatment options have not yet been established. In our case, after a composite graft, we performed HBOT. This approach has 2 advantages with respect to wound healing. First, it is known to promote healing by increasing reperfusion [2]. In cases of a composite graft without microvascular anastomosis, it is crucial for adequate blood circulation to be supplied during wound healing. This increases angiogenesis and stimulates fibroblast proliferation [2]. Thus, the survival of compromised skin grafts and flaps can be increased by oxygen therapy [3]. Oxygen therapy has also been proven to have a bactericidal effect [4]. In cases of human bite injury, there is a higher risk of infection than in injuries due to other causes because of the vast array of bacterial species in the mouth [5]. A few case reports have described employing HBOT as an adjunctive method for composite grafts. However, in order to implement HBOT, equipment such as a high-pressure oxygen hood or a chamber is necessary. Such equipment is not available in many hospitals. We performed adjunctive HBOT by connecting oxygen to a plastic bag around the wound at the patient’s bedside. In our case, HBOT was employed and was effective for improving composite graft survival. Compared to conventional methods of administration using a chamber or a hood, this method can be more easily applied to patients if it is possible to supply pure oxygen at the bedside. Therefore, if a chamber or a hood for HBOT is not available, our method can be used as a treatment strategy.