Protective Effect of Ebselen on Ischemia-reperfusion Injury in Epigastric Skin Flaps in Rats.

The purpose of this study was to determine the role of oxidized diacylglycerol (DAG) and the molecular mechanism underlying ischemia-reperfusion (I/R) injury in rat skin flaps. The protective effect of ebselen on the viability of rat skin flaps with I/R injury was investigated. Flaps were designed and raised in the left inguinal region. Then, a microvascular clamp was applied to the vascular pedicle and reperfused after 6 hr. After 7 days of I/R (I/R group), the skin flap survival area ratio was significantly reduced compared to the normal skin. The administration of ebselen significantly improved the ratio compared to the I/R group. The flap survival area ratio of the I/R + ebselen group was significantly improved compared to the I/R + vehicle group. In the I/R + ebselen group, the oxidized DAG content and intensity of phosphorylated PKCα and PKCδ were significantly lower compared to the I/R + vehicle group. Furthermore, the inflammatory response was suppressed in the I/R + ebselen group compared to the I/R + vehicle group. These results indicate that ebselen is useful as a preventive and therapeutic agent for skin flap necrosis caused by I/R, because of reduction and elimination of oxidized DAG.

An Adverse Implication of Radiation Therapy for Implant-Retained Maxillofacial Prostheses.

We report the 19-year postoperative course of a patient whose maxillary defect was reconstructed with maxillofacial implant-retained facial prostheses. The patient received 60 Gy of radiation therapy. Adjunctive hyperbaric oxygen therapy was administered and four 4.0-mm long maxillofacial implants were inserted. Four years and 6 months after insertion surgery, two of the four implants were lost and the others showed bone regression in the surrounding bone. All implants were replaced with Epitec System maxillofacial implants placed in non-irradiated bone. Eleven years and 6 months after replacement, the Epitec System has been maintaining good and firm osseointegration. Appropriate selection of implant sites and no history of radiation therapy are keys to successful implant reconstruction. However, adjunctive hyperbaric oxygen therapy is believed to be effective, osseointegrated implant should be inserted at a point appropriately distant from an irradiated lesion.

Cranial Reconstruction in a Pediatric Patient Using a Tissue Expander and Custom-made Hydroxyapatite Implant.

A tissue expansion technique in conjunction with a custom-made artificial bone implant was effective for a large cranial reconstruction in a pediatric patient. The patient was an eight-year-old boy with cranial bone fracture, acute subdural hematoma in the left lobe, and acute epidural hematoma in the right lobe due to an accident. Wound dehiscence and artificial dura infection were observed as postoperative complications. Because of insufficiency of the skin flap caused by scar contracture, a scalp skin expansion using a tissue expander was necessary before reconstruction with the artificial bone implant. This combined procedure provided safe coverage of the implant and resulted in good wound healing. There are relatively few reports involving the use of tissue expanders for cranioplasty; furthermore, our search of the literature did not reveal any reports involving children. We believe that this procedure is safe and effective for early rehabilitation in pediatric patients.