Full-thickness reconstruction of the eyelid with rotation flap based on orbicularis oculi muscle and palatal mucosal graft: long-term results in 12 cases.

BACKGROUND: Numerous techniques have been proposed for full-thickness eyelid reconstruction. Previously, we reported full-thickness eyelid reconstruction with a rotation flap based on the orbicularis oculi muscle and palatal mucosal graft. Here, we report long-term results in 12 cases. METHODS: After confirmation of defect size, the mucosal defect was covered with a split-thickness palatal mucosal graft. The rotation flap was elevated at the lateral orbital region and the skin defect was covered. Seven cases were reconstructions after tumour excision and five cases were for lagophthalmos after trauma. In cases of tumour excision, five cases had full defects of the lower eyelid and two cases had defect of the lower eyelid lateral to the punctum. In the cases of lagophthalmos, four cases had upper eyelid contracture and one had lower eyelid contracture. RESULTS: Postoperatively, one case showed severe venous congestion of the flap, which led to scleral show. In the other 11 cases, there were no complications, and cosmetic results were excellent. CONCLUSIONS: With our method, cosmetically good results can be obtained in either upper or lower eyelids. In the rotation flap based on the orbicularis oculi muscle, the undermined area is small, invasion is minimal, and the effects of scar contracture can be minimised. Minimal shrinkage of palatal mucosal grafts prevents the reconstructed eyelid from sagging. In only one case, poor design of the flap led to flap congestion. However, this complication can be avoided with the proper design.

Mutual dependence of murine fetal cutaneous regeneration and peripheral nerve regeneration.

Mammalian fetal cutaneous wounds made at certain developmental stages show complete regeneration. It is reported that wound healing in both adult and fetal skin is disrupted by denervation. Furthermore, fetal cutaneous regeneration has unique aspects such as epidermal wrinkle texture regeneration and dermal regeneration that depend on developmental stage. Therefore, we have examined the relationship of fetal cutaneous regeneration with denervation. We made cutaneous wounds on fetal mice at various developmental time points including embryonic days (E)13, E15, and E17, and compared the regenerating patterns of peripheral nerves in the skin. We found that when the fetuses are wounded at an early stage of development, peripheral nerves regenerate quicker than at later stages of development when peripheral nerve regeneration is delayed. Next, we denervated the intercostal nerves and made wounds at the denervated sites on E13 and E15. We found that epidermal wrinkling and dermal regeneration were disrupted by denervation. These findings indicate that components of fetal cutaneous regeneration and peripheral nerve regeneration are mutually dependent.

Transplanted mesenchymal stem cells are effective for skin regeneration in acute cutaneous wounds.

Mesenchymal stem cells (MSCs) possess the capacity for site-specific differentiation of cell types in response to cues provided by different organs. This phenomenon suggests that MSCs participate in cutaneous wound regeneration. However, there are no prior reports on the influence of the local application of MSCs on cutaneous wound regeneration. To examine the effects of MSCs on wound regeneration, we cultured bone marrow cells of the femur of rats and treated the plastic adherent cells with a differentiation medium to induce differentiation. After treatment, we found that the bone marrow-derived plastic adherent cells possessed myogenesis, chondrogenesis, and adipogenesis capabilities, indicating that these cells are MSCs. The bone marrow-derived plastic adherent cells were injected intradermally into the skin of rats, and linear full-thickness incisional wounds were made immediately through the injected area. At 14 days after operation, wounds transplanted with bone marrow-derived plastic adherent cells had healed with very fine scars. Collagen architecture was thick and appeared to be similar to normal dermis. Histomorphologic scale analysis demonstrated significant differences between the control and the wounds transplanted with bone marrow-derived plastic adherent cells. These results indicate that transplanted MSCs can respond quite normally to wound healing and regenerate dermal structure.

Transplanted endothelial progenitor cells augment the survival areas of rat dorsal flaps.

Endothelial progenitor cells (EPCs) have been identified in peripheral blood, and have been reported to be incorporated into ischemic regions such as the ischemic hindlimb. In this study, we examined whether or not transplantation of EPCs is useful for salvaging surgical flaps in vivo. At the same time, we quantitatively compared the neovascularization ability of transplanted EPCs and that of mature endothelial cells (ECs). ECs obtained from the aorta of rats by explantation and passaged several times were used in the present study. EPCs were obtained from the blood of rat hearts. The blood samples were separated by density gradient centrifugation. Light-density mononuclear cells (MNCs) were collected and cultured on plastic plates coated with rat plasma vitronectin. Cells attached at day 7 of culture were deemed to be EPCs. Then PBS (control), ECs, or EPCs (3.0 x 10(5) suspended in 1.0 ml PBS) were injected at the middle of a flap. Seven days after surgery, the survival lengths of the flaps were evaluated. EPC-transplanted groups revealed statistically significant augmentation of survival length compared with the other two groups (p < 0.003). EPC-transplanted groups had significantly more angiographically detectable blood vessels (p < 0.003) and significantly higher capillary density (p < 0.03) than the other two groups. Confocal microscopy revealed that EPCs were incorporated into enhanced neovascularization. These results suggest that transplantation of EPCs may be useful for salvaging surgical flaps, and EPCs are superior to ECs in neovascularization ability.