In this study, we examined 32 cases of implant exposure managed using a supra-brow island flap pedicled with orbicularis oculi muscle autograft. In 28 of the participants, the exposure was successfully repaired with no complications, while in 4 subjects, a second procedure for re-exposure was required. This is the frist time using this technique as the wrapping material of orbital implant.
Implant exposure is a common complication after evisceration, enucleation or socket surgery. It is reported that the exposure rate of acrylic or silicone implants is higher than that of hydroxyapatite implants[7, 14]. Some factors are associated with a higher risk of implant exposure or graft failure, such as wound healing problems, infection, previous radiation history or improper surgical operation. In order to avoid this complication, the appropriate size of the implant should be accurately evaluated before implantation, and the Tenon sac and conjunctiva on the surface of implant should be accurately closed without tension[1–3].
Several factors, such as the size of the defect, the presence of infection, and implant vascularity determine the management of implant exposure. Spontaneous healing of exposure of small orbital implants with an areas less than 4mm2 can be observed with or without antibiotics[16–17], while for large exposures, surgical treatment is recommended, or the exposure is not resolved in 8 weeks after conservative treatment[3, 8, 18]. Implants with good-vascularization can be treated with antibiotics, and implants with poor vascularization should be replaced.
The ideal graft material should be adaptable to the socket surface, resistant to infection and easily epithelializing, provide scaffold to prothetic eye. Previously described materials for manage of exposed orbital implants include: dermis fat, temporalis fascia graft, frontal periosteum graft, tarsal patch flap, amniotic membrane graft, retroauricular myoperiostal graft or biosynthetic material patch graft as described by Enduragen[19, 20].
We report a technique to repair an exposed orbital implant using a supra-brow island flap pedicled with orbicularis oculi muscle autograft. The supra-brow island flap pedicled with orbicularis oculi muscle autograft is an autogenous graft from the homolateral upper eyelid with easy donor site access and reducing the incidence of immune rejection or infection. It is well known that good vascular supply is essential for graft survival. For our supra-brow island flap pedicled with orbicularis oculi muscle graft, the surrounding subconjunctival tissue and the orbicularis oculi muscle provide a good vascular supply.
Failure of final coverage or persistant infection is a major risk factor of treatment for orbital implant exposure, especially in acrylic implants and ocular cancer cases[21, 22], where removal of implants and autologous demis fat transplantation seems preferable. The main disadvantage of the island flap pedicled with orbicularis oculi muscle technique is the scar on the upper eyebrow, there are also theorical risks such as ptosis, fornix shortening, palpebral retraction or hemorrages, however, there was no complication in our subjects. Further studies comparing this technique with other operative techniques are needed to assess the use of this flap for manage orbital plant exposure.
The island flap pedicled with orbicularis oculi muscle is located in the adjacent surgical area because most opththalmic surgeons have some knowledge of the anatomy of the area. We recommend that this autograft be used to manage orbital plant exposure, especially in patients larger than 4mm2, without orbital radiotherapy or fornix injury. However, in the case of chronic inflammation or recurrent infection, orbital implants need to be removed and replaced with a dermal fat graft. The supra-brow island flap pedicled with orbicularis oculi muscle is a reliable technique with high success rate, which can retain the implant and easy to use a new prosthesis.