The most common indication for conjunctival transplantation is advanced primary and recurrent pterygium. This technique reduces the risk of pterygium recurrence to approximately 3%–5% and ameliorates the restriction of extraocular muscle function sometimes encountered after pterygium excision. Because the superior bulbar conjunctiva is usually normal and undamaged due to reduced exposure to ultraviolet light and chemical irritants, conjunctival autograft tissue can be obtained from this area in the same eye.
Various techniques of conjunctival transplantation have been used to manage pterygium. The procedure is performed on an outpatient basis, using topical plus peribulbar or retrobulbar anesthetic, especially in recurrent cases complicated by scarring. A traction suture (eg, 6-0 on a spatulated needle) placed at the 12 o’clock position, which can then be clamped down in various positions to the surgical drape, facilitates maximal exposure of the pterygium and the graft site. The pterygium is usually excised with a #57 blade or an angled crescent blade. It is important to remove as much of the fibrovascular scar tissue as possible. If the medial rectus muscle is restricted, it must be isolated, preserved, and carefully freed of all scar tissue. A smooth surface at the site of dissection is a desirable endpoint. With the eye in abduction, the size of the defect is measured with calipers. It is best to allow a little extra tissue for grafting, so the harvested tissue should be approximately 0.5–1.0 mm larger than the size of the defect.
The eye is then turned down to expose the superior bulbar conjunctiva, and the area to be harvested is marked with multiple focal cautery spots or with a surgical pen. The most important aspect of the harvesting is to procure conjunctival tissue with only minimal or no Tenon included. This may be facilitated by injecting a small amount of anesthetic between the conjunctiva and Tenon fascia. Some surgeons make a special point of harvesting limbal stem cells along with the conjunctiva and orienting the donor material in the host bed so that the stem cells are adjacent to the site of corneal lesion excision. The donor site is usually left bare. After the graft is freed, it is transferred to the recipient bed and secured to adjacent conjunctiva (with or without incorporating episclera) with either absorbable (eg, 10-0 Vicryl or 10-0 Biosorb) or nonabsorbable (10-0 nylon) sutures or tissue adhesive. Postoperatively, topical antibiotic-corticosteroid ointment is administered frequently for approximately 4–6 weeks, until inflammation subsides. The surgeon should emphasize to the patient that compliance with this regimen minimizes the chance of recurrence.
If the defect created following dissection of scar tissue is considerably larger than what can be covered with an autologous conjunctival graft, then an amniotic membrane graft may be used in conjunction with a conjunctival graft to cover the entire area of resection. Several authors have noted that this decreases postoperative inflammation and speeds reepithelialization of the surface.
Many authors have described the use of commercially available fibrin tissue adhesive (eg, Tisseel VH) to fixate the conjunctival autograft, thereby eliminating the need for suture fixation. Elimination of sutures decreases postoperative pain and reduces surgical time as well as the recurrence rate, compared with bare sclera techniques. Fibrin tissue adhesive mimics natural fibrin formation, ultimately resulting in the formation of a fibrin clot. Currently, use of this product in pterygium surgery is not FDA approved; its use should be considered off-label. Also, because both pooled human plasma and bovine products are used to obtain some of its components, careful consideration should be given to the potential of the product for disease transmission.
, AkovaYA, AltinörsDD. Comparison of conjunctival autograft with amniotic membrane transplantation for pterygium surgery: surgical and cosmetic outcome.2007;26(4):407–413.
, TsengSC. Management of primary and recurrent pterygium using amniotic membrane transplantation.2002;13(4):204–212.
, ReyesJM, FloresJD, Lim-Bon-SiongR. Comparison of fibrin glue and sutures for attaching conjunctival autografts after pterygium excision.2005;112(4):667–671.