Current concepts and techniques in pterygium treatment Ang , and Donald T.H. Tan
Transcription
Current concepts and techniques in pterygium treatment Ang , and Donald T.H. Tan
Current concepts and techniques in pterygium treatment Leonard P.K. Anga,b,c, Jocelyn L.L. Chuaa,c and Donald T.H. Tana,b,c Purpose of review Pterygium is a common ocular disorder in many parts of the world. At present, there is a wide variety of surgical methods but very few clinical guidelines on the optimal treatment of primary or recurrent pterygium. The purpose of this review is to summarize the more recent and relevant studies on pterygium treatment. Recent findings The primary aim is to excise the pterygium and prevent its recurrence. As bare sclera excision is associated with a high recurrence rate, pterygium excision is often combined with conjunctival autograft, mitomycin C, beta-irradiation or other adjunctive therapies to reduce recurrence rates. There is currently, however, no consensus regarding the ideal treatment for the disease. Comparability between studies is also hampered by the various definitions of pterygium recurrence. Summary This article reviews the current concepts and techniques used for the treatment of pterygium. Conjunctival autografting and mitomycin C application are the most commonly used methods for preventing recurrences. The use of mitomycin C and beta-irradiation should be used judiciously because of the potential long-term risk of sight-threatening complications. Additional clinical trials should be performed to evaluate the relative efficacies and long-term safety of the various treatment modalities. Keywords beta irradiation, conjunctival graft, excision, mitomycin, pterygium Curr Opin Ophthalmol 18:308–313. ß 2007 Lippincott Williams & Wilkins. a Singapore National Eye Centre, bDepartment of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore and c Singapore Eye Research Institute, Singapore Correspondence to Leonard P.K. Ang, MD, Singapore National Eye Centre, 11 Third Hospital Avenue, Singapore 168751 Tel: +65 62277255; fax: +65 62277266; e-mail: [email protected] Introduction Pterygium is a common disorder in many parts of the world, with reported prevalence rates ranging from 0.3 to 29% [1,2]. Epidemiological studies [1,2] suggest an association with chronic exposure to sunlight, with an increased geographical prevalence within a peri-equatorial ‘pterygium belt’ of latitudes of 378 north and south of the equator. The various treatments for pterygium are aimed at reducing recurrence of the lesion. Over the years, many surgical procedures to excise this recurrent disorder have been described. An excellent and comprehensive review of the existing literature by Hirst [3] demonstrated the wide variation in the modern surgical techniques and reported success rates for pterygium surgery today. The purpose of this review is to present a summary of the more recent literature, paying particular attention to prospective randomized studies. We also included our views and personal experience in the management of this disease. Current concepts in pterygium pathogenesis The UV type B light in solar radiation has been found to be the most significant environmental factor in pterygium pathogenesis [1,2]. Recent studies [4–7] have suggested that p53 and human papillomavirus may also be implicated in pterygium pathogenesis. UV radiation can cause mutations in genes such as the p53 tumor suppressor gene, resulting in its abnormal expression in pterygial epithelium. These findings suggest that pterygium is not just a degenerative lesion, but could be a result of uncontrolled cell proliferation [6,7]. Matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) at the advancing pterygium edge may be responsible for the inflammation, tissue remodeling, and angiogenesis that characterize pterygia, as well as the destruction of Bowman’s layer and pterygium invasion into the cornea [4–7]. Tseng et al. [8] have also speculated that pterygium may represent an area of localized limbal stem cell deficiency. Current Opinion in Ophthalmology 2007, 18:308–313 ß 2007 Lippincott Williams & Wilkins 1040-8738 Pterygium recurrence The definition of pterygium recurrence varies among studies. Most ophthalmologists define pterygium recurrence as corneal recurrence, which include regrowth of fibrovascular pterygium-like tissue crossing the limbus onto the cornea, fibrovascular recurrence attaining the same degree of corneal encroachment as the original lesion, or regrowth exceeding 1 mm onto the cornea. 308 Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Pterygium treatment Ang et al. 309 Treatment of pterygium The main aims of surgery are to completely excise the pterygium and to prevent its recurrence. recurrence rates associated with intraoperative and postoperative mitomycin C use are not significantly different. Intraoperative mitomycin C treatment Pterygium excision Removal of the pterygium involves surgical excision of the head, neck and body of the pterygium. The body and base of the pterygium are dissected with conjunctival scissors, while the head and neck of the pterygium that has invaded the cornea is often removed with a surgical blade. An attempt is made to identify the plane of dissection, which facilitates removal of the pterygium while keeping the underlying corneal surface smooth. Remnant stromal attachments may be smoothed out with the blade. As the body of the pterygium has no clearly defined margin, the extent of surgical excision of the pterygium and subconjunctival fibrovascular tissue varies between reports. Our preferred method is to excise the base of the pterygium approximately 4–6 mm from the limbus, as retraction of the surrounding conjunctiva results in enlargement of the surgical defect. If no additional measures are performed, pterygium excision alone is commonly referred to as bare sclera excision. The recurrence rates for bare sclera excision alone are unacceptably high (ranging from 30 to 80%) when compared with other treatment modalities [9–11]. As such, bare sclera excision alone is no longer recommended for the treatment of pterygium. The concentration of intraoperative mitomycin C application used in most of the studies range from 0.01 to 0.04%, with 0.02% applied for 3 min being the commonest dosage used [9,10,12–14]. The reported recurrence rates associated with intraoperative mitomycin C use range from 3 to 37.9%. In the study by Lam et al. [10] intraoperative mitomycin C was associated with significantly reduced recurrence rates compared with cases where no adjunctive treatment was used. It was further shown that application of 0.02 and 0.04% intraoperative mitomycin C for 3 min was less effective than application for 5 min. Increasing the duration and concentration of mitomycin C, however, may lower the risk of recurrence, but may lead to a higher risk of complications. Postoperative mitomycin C treatment Postoperative mitomycin C eyedrops have also been shown to be effective, with 0.02% being the commonest concentration used (concentrations used range from 0.005 to 0.04%) [11,13–15]. These were generally prescribed at a frequency of four times a day, with the duration of application varying from 5 to 14 days (mean duration of application, 10 days). The reported recurrence rates range from 0 to 38% [11,13–15]. Cardillo et al. [13] compared the use of mitomycin C postoperatively for 7 and 14 days and showed that there was no significant difference in the final outcome, suggesting that the shorter period may be equally efficacious, and may also reduce the risk of complications. Prevention of pterygium recurrence Pterygium excision is often combined with various adjunctive measures to prevent recurrence of the disease. These may be broadly classified as adjunctive medical methods, beta-irradiation, and surgical methods. Medical methods Intraoperative and postoperative mitomycin C remain the most commonly used medical adjunctive therapies for the prevention of pterygium recurrence. Several other medical alternatives, such as 5-fluorouracil and daunorubicin, have also been tried. Mitomycin C treatment Mitomycin C treatment has been shown to be effective in preventing recurrence for primary and recurrent pterygium [9–15]. The recurrence rates associated with mitomycin C treatment are significantly lower compared with bare sclera excision. Essentially two forms of mitomycin C application are currently used – the intraoperative application of surgical sponges soaked in mitomycin C solution applied directly to the scleral bed after pterygium excision, and the postoperative use of topical mitomycin C as eyedrops [9–16]. Studies [11,13,14] have shown that the Although mitomycin C has been shown to be an effective treatment for pterygium, its use has been associated with serious sight-threatening complications, which may present many years after surgery, such as scleral necrosis, infectious scleritis, perforation and endophthalmitis [17]. Patients should be counseled regarding the potential for rare, but serious long-term sight-threatening complications related to its use. Other medical treatment Several isolated studies have proposed alternative methods of treatment. Dadeya and Kamlesh [18] demonstrated a statistically significant difference in the recurrence rate of patients who were treated with daunorubicin and those that received water placebo. Treated eyes were more chemotic (20%), however, with 6.7% having delayed epithelialization, compared with the control eyes, which did not have similar complications. Sodhi et al. [19] reported comparable results with the use of doxorubicin and mitomycin C. In a study that evaluated the use of 5-fluorouracil, Maldonado et al. [20] reported that this was not effective in preventing pterygium recurrence. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 310 Corneal and external disorders A randomized controlled prospective study [21] comparing 5-fluorouracil to conjunctival autograft showed a marginal reduction in recurrence rate with the former. Larger randomized clinical trials with longer follow-up periods would need to be performed to evaluate the efficacy and long-term safety of each of these potential treatment options. Beta-irradiation Various regimes of beta-irradiation have been used to treat pterygium, including a single application of beta-irradiation, several applications over consecutive days in the immediate postoperative period, or several applications periodically over a 2-week period [22–24]. Although this modality of treatment has been used for decades, few prospective studies have been described. The use of postoperative single dose irradiation was demonstrated to be similarly efficacious as consecutive days of postoperative application. Chayakul [22] showed that beta-irradiation was associated with a significantly higher recurrence rate than postoperative mitomycin C eyedrops. Beta-irradiation is a less popular procedure because of the inconvenience of arranging its treatment and the longterm risk of serious sight-threatening complications, such as scleral necrosis, infectious scleritis, corneal perforation and endophthalmitis [25]. Patients should therefore be counseled regarding the potential long-term complications arising from its use. Surgical methods The surgical options available include the use of conjunctival autograft, limbal and limbal–conjunctival transplant, conjunctival flap and conjunctival rotation autograft surgery, amniotic membrane transplant, cultivated conjunctival transplant, lamellar keratoplasty and use of fibrin glue. Conjunctival autografts Conjunctival autograft surgery is generally regarded as the procedure of choice for the treatment of primary and recurrent pterygium, because of its efficacy and longterm safety [26–32]. A free conjunctival graft is harvested from the superior bulbar conjunctiva and is sutured in place over the bare scleral defect [9–11,13,14]. Variations in conjunctival autograft surgery include the use of narrow-strip conjunctival autograft, limbal–conjunctival autografts, limbal epithelial autografts, conjunctival flaps or conjunctival rotation autografts [29,33–39]. A retrospective noncomparative case series [40] has shown that juxtalimbal narrow-strip conjunctival autograft with posterior epithelized bare sclera zone is effective in preventing pterygium recurrence. Conjunctival autografts are associated with recurrence rates (ranging from 2 to 39%) that are comparable to that of mitomycin C and beta-irradiation, without the attendant risk of sight-threatening complications associated with mitomycin C or beta-irradiation usage [27,28]. Sharma et al. [28] demonstrated that there was no statistically significant difference in the recurrence rates between conjunctival autografting and mitomycin C use. A combination of conjunctival autograft with low dose (0.2 mg/ml) mitomycin C was shown in a prospective randomized comparative study by Frucht-Pery et al. [41] to have a significantly lower recurrence rate compared with conjunctival graft alone. ComparedwiththeuseofmitomycinC andbeta-irradiation, conjunctival autografting is more technically demanding and more time-consuming to perform. Inter-surgeon variability in terms of surgical technique, skill and experience contributes to the wide variation in recurrence rates that have been reported. Once the surgical technique is mastered, however, conjunctival autografting is generally considered to be a better option than the other treatment modalities, because of its proven efficacy and its long safety record. Limbal and limbal–conjunctival transplantation It has been suggested that including limbal stem cells in the conjunctival autograft (limbal–conjunctival graft) may act as a barrier to conjunctival cells migrating onto the corneal surface and help prevent recurrence. The limbal–conjunctival graft includes approximately 0.5 mm of the limbus and peripheral cornea. The corneal limbal side of the graft is sutured in place with interrupted 10/0 nylon sutures, and the conjunctival side is sutured with 10/0 absorbable sutures. The recurrence rates after limbal–conjunctival autograft surgery (ranging from 0 to 15%) are similar to that of conjunctival autograft surgery [29,33–35], while some authors suggest that limbal–conjunctival autografts are more effective than conjunctival autografts for recurrent pterygium [34]. Oguz et al. [42] demonstrated an overall recurrence rate of 9.52% with limbal conjunctival miniautografting performed in 63 eyes. Young et al. [35] prospectively compared mitomycin C and limbal– conjunctival autograft surgery in preventing pterygial recurrence, and showed that the mitomycin C group was associated with a higher recurrence rate (15.9%) compared with the limbal–conjunctival autograft group (1.9%). A major drawback for limbal–conjunctival autograft transplantation is that it is technically more demanding and time-consuming to perform. To date, however, it should be noted that no conclusive evidence regarding the superiority of limbal–conjunctival autografts over conventional conjunctival autografts exists, and the added risk of limbal damage at the donor site deserves consideration. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Pterygium treatment Ang et al. 311 Conjunctival flap and conjunctival rotation autograft surgery Lamellar keratoplasty Two reports [36,37] have described the use of sliding conjunctival flaps harvested from the inferior or the superior bulbar conjunctiva to close the scleral defect, with reported recurrence rates ranging from 1 to 5%. Conjunctival rotation autografting involves removal of the pterygium and reversal of the removed conjunctiva so that the most nasal aspect is sutured at the limbus and vice versa [38,39]. This is a useful technique for cases in which it is not possible or desirable to use the superior conjunctiva as a donor source, such as with excision of extensive pterygium, which leaves insufficient conjunctival tissue for the autograft. Lamellar keratoplasty has been used to act as a barrier against pterygium recurrence and to replace thinned and scared corneal tissue after pterygium excision [52]. It does not appear to offer any special advantage in preventing pterygium recurrence, with recurrence rates ranging from 6 to 100% [52]. As such this is not a favored procedure for treating primary pterygium. It has mostly been used to treat recurrent pterygium to restore corneal thickness in thinned, scarred corneas. The main limitations are the need for donor corneal tissue with the attendant risks of graft rejection and transmission of infection, as well as the increased complexity of the procedure. Amniotic membrane transplantation Fibrin glue Amniotic membrane transplantation has recently been proposed as a treatment option [43–46]. Ma et al. [44] compared the excision of recurrent pterygia followed by amniotic membrane alone and amniotic membrane graft combined with intraoperative mitomycin C, and found no significant difference in the recurrence rates between the two groups. Amniotic membrane possesses antiscarring, antiangiogenic and anti-inflammatory properties, which may be useful for treating pterygium. Besides the conventional epithelized cryopreserved human amniotic membrane, the efficacy of membranes that are alternatively prepared such as the de-epithelized [47] or freezedried sterilized ones [48] have also been studied. Delayed vascularization of amniotic membrane demonstrated with an anterior segment indocyanine green angiography is thought to be responsible for the delayed recurrence after pterygium surgery [49]. An additional advantage is that it removes the need for harvesting large autografts, thereby minimizing iatrogenic injury to the rest of the conjunctiva surface. Three prospective studies [44,45,50] have compared amniotic membrane transplantation with other conventional treatment modalities. In a randomized prospective study by Tananuvat et al. [45], amniotic membrane transplant is associated with an unacceptably high recurrence rate compared with conjunctival autograft. This result is also supported by Luanratanakorn et al. [50]. Fibrin glue (or Tisseel) has been used as an alternative to sutures for securing conjunctival grafts [53–56]. The use of fibrin glue shortens operating times significantly and is associated with less postoperative discomfort. Fibrin glue also provides a more even attachment of the graft to the scleral bed. Most cases performed with fibrin adhesive healed with minimal inflammation and there were only sporadic cases of graft dislodgment or loss. Cultivated conjunctival transplantation A novel method of closing the surgical defect involves the use of an ex-vivo expanded conjunctival epithelial sheet on an amniotic membrane substrate. Although the preliminary study [51] demonstrated no significant difference in the recurrence rate compared with denuded amniotic membrane transplantation, operated eyes achieved almost immediate reepithelialization of the ocular surface, reduced postoperative inflammation and faster ocular rehabilitation. This procedure may be particularly useful for closing large surgical defects following excision of extensive pterygium. In a retrospective study, Koranyi et al. [54] demonstrated a pterygium recurrence rate of 5.3% with glue versus 13.5% with sutures. The authors suggested that immediate adherence of the graft and the lack of postoperative inflammation may inhibit fibroblast ingrowth and reduce recurrence. Bahar et al. [57] showed that the use of fibrin glue was associated with a significantly shorter operative time and greater patient acceptance compared with using sutures. The major concerns that need to be addressed include the cost of Tisseel and the potential risk of transmitted infection. Further studies are required to evaluate the long-term efficacy of fibrin glue in reducing recurrences. Complications of treatment Operative complications related to pterygium excision are uncommon, and are generally related to the surgical technique. This includes excessive bleeding, button hole of the conjunctiva graft, perforation of the globe with the suture needle, and injury to the medial rectus muscle. The main postoperative complication is recurrence. Other complications such as pyogenic granuloma, dellen, persistent epithelial defects are not uncommon, but these may be easily treated with no significant long-term sequelae. Of greater concern is the potentially serious sight-threatening complications that have been associated with the use of adjunctive mitomycin C and beta-irradiation, such as scleral necrosis, infectious scleritis, severe secondary glaucoma, iritis, cataract, corneal edema, corneal perforation, Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. 312 Corneal and external disorders and endophthalmitis [17,25]. Complications arising from the use of beta irradiation have been reported in up to 13% of patients, with latency periods of up to 14.5 2.5 years [25]. These serious complications represent cases in which surgery was performed some years back, when relative therapeutic doses of both mitomycin C and beta irradiation were higher, and it remains to be seen if the newer treatments with reduced therapeutic dosages are associated with similar complications. Conclusion Pterygium excision combined with mitomycin C or conjunctival autograft surgery are currently the main methods used for treating pterygium. As the clinical trials describing various surgical techniques often have differing methodology and sometimes conflicting results, additional large randomized clinical trials need to be performed to evaluate the relative efficacy and long-term safety of the various treatment options. Issues that need to be addressed include developing a standardized method of grading pterygium and its recurrence, as well as identifying risk factors for pterygium recurrence. References and recommended reading Papers of particular interest, published within the annual period of review, have been highlighted as: of special interest of outstanding interest Additional references related to this topic can also be found in the Current World Literature section in this issue (p. 344). 15 Raiskup F, Solomon A, Landau D, et al. Mitomycin C for pterygium: long term evaluation. Br J Ophthalmol 2004; 88:1425–1428. 16 Segev F, Jaeger-Roshu S, Gefen-Carmi N, Assia EI. Combined mitomycin C application and free flap conjunctival autograft in pterygium surgery. Cornea 2003; 22:598–603. 17 Rubinfeld RS, Pfister RR, Stein RM, et al. Serious complications of topical mitomycin-C after pterygium surgery. Ophthalmology 1992; 99:1647– 1654. 18 Dadeya S, Kamlesh. Intraoperative daunorubicin to prevent the recurrence of pterygium after excision. Cornea 2001; 20: 172–174. 19 Sodhi PK, Verma L, Pandey RM, Ratan S. Comparison between the role of intraoperative mitomycin C and doxorubicin in preventing the recurrence of primary pterygium. Ophthalmic Res 2004; 37:1–6. 20 Maldonado MJ, Cano-Parra J, Navea-Tejerina A, et al. Inefficacy of low-dose intraoperative fluorouracil in the treatment of primary pterygium. Arch Ophthalmol 1995; 113:1356–1357. 21 Bekibele CO, Baiyeroju AM, Olusanya BA, et al. Pterygium treatment using 5-FU as adjuvant treatment compared to conjunctiva autograft. Eye 2006; Jun16 [Epub ahead of print]. 22 Chayakul V. Postoperative mitomycin C eye drop and beta radiation in the treatment of pterygia. J Med Assoc Thai 1991; 74:373–376. 23 Jurgenliemk-Schulz IM, Hartman LJ, Roesink JM, et al. Prevention of pterygium recurrence by postoperative single-dose beta-irradiation: a prospective randomized clinical double-blind trial. Int J Radiat Oncol Biol Phys 2004; 59:1138– 1147. 24 Pajic B, Greiner RH. Long term results of nonsurgical, exclusive strontium-/ yttrium-90 beta-irradiation of pterygia. Radiother Oncol 2005; 74:25–29. 25 Moriarty AP, Crawford GJ, McAllister IL, Constable IJ. Severe corneoscleral infection: a complication of beta irradiation scleral necrosis following pterygium excision. Arch Ophthalmol 1993; 111:947 –951. 26 Tan DT, Chee SP, Dear KB, Lim AS. Effect of pterygium morphology on pterygium recurrence in a controlled trial comparing conjunctival autografting with bare sclera excision. Arch Ophthalmol 1997; 115:1235 – 1240. 27 Mutlu FM, Sobaci G, Tatar T, Yildirim E. A comparative study of recurrent pterygium surgery: limbal conjunctival autograft transplantation versus mitomycin C with conjunctival flap. Ophthalmology 1999; 106:817–821. 28 Sharma A, Gupta A, Ram J, Gupta A. Low-dose intraoperative mitomycin-C versus conjunctival autograft in primary pterygium surgery: long-term followup. Ophthalmic Surg Lasers 2000; 31:301–307. 1 Moran DJ, Hollows FC. Pterygium and ultraviolet radiation: a positive correlation. Br J Ophthalmol 1984; 68:343–346. 2 Taylor HR, West S, Munoz B, et al. The long-term effects of visible light on the eye. Arch Ophthalmol 1992; 110:99–104. 3 Hirst LW. The treatment of pterygium. Surv Ophthalmol 2003; 48:145–180. 29 Frau E, Labetoulle M, Lautier-Frau M, et al. Corneo–conjunctival autograft transplantation for pterygium surgery. Acta Ophthalmol Scand 2004; 82:59– 63. 4 Di Girolamo N, Chui J, Coroneo MT, Wakefield D. Pathogenesis of pterygia: role of cytokines, growth factors, and matrix metalloproteinases. Prog Retin Eye Res 2004; 23:195–228. 30 Gris O, Guell JL, del Campo Z. Limbal–conjunctival autograft transplantation for the treatment of recurrent pterygium. Ophthalmology 2000; 107:270– 273. 5 Gallagher MJ, Giannoudis A, Herrington CS, Hiscott P. Human papillomavirus in pterygium. Br J Ophthalmol 2001; 85:782–784. 6 Reisman D, McFadden JW, Lu G. Loss of heterozygosity and p53 expression in pterygium. Cancer Lett 2004; 206:77–83. 31 Miyai T, Hara R, Nejima R, et al. Limbal allograft, amniotic membrane transplantation, and intraoperative mitomycin C for recurrent pterygium. Ophthalmology 2005; 112:1263–1267. 7 Tan DT, Tang WY, Liu YP, et al. Apoptosis and apoptosis related gene expression in normal conjunctiva and pterygium. Br J Ophthalmol 2000; 84:212–216. 33 Du Z, Jiang D, Nie A. Limbal epithelial autograft transplantation in treatment of pterygium. Chin J Ophth 2002; 38:351–354. 8 Tseng SCG, Chen JJY, Huang AJW, et al. Classification of conjunctival surgeries for corneal diseases based on stem cell concept. Ophthalmol Clin North Am 1990; 3:595–610. 34 Al-Fayez M-F. Limbal versus conjunctival autograft transplantation for advanced and recurrent pterygium. Ophthalmology 2002; 109:1752 – 1755. 9 Frucht-Pery J, Charalambos SS, Ilsar M. Intraoperative application of topical mitomycin C for pterygium surgery. Ophthalmology 1996; 103:674–677. 35 Young AL, Leung GY, Wong AK, et al. A randomised trial comparing 0.02% mitomycin C and limbal conjunctival autograft after excision of primary pterygium. Br J Ophthalmol 2004; 88:995–997. 10 Lam DS, Wong AK, Fan DS, et al. Intraoperative mitomycin C to prevent recurrence of pterygium after excision: a 30-month follow-up study. Ophthalmology 1998; 105:901–904. 11 Gupta VP, Saxena T. Comparison of single-drop mitomycin C regime with other mitomycin C regimes in pterygium surgery. Ind J Ophth 2003; 51:59–65. 12 Manning CA, Kloess PM, Diaz MD, Yee RW. Intraoperative mitomycin in primary pterygium excision: a prospective, randomized trial. Ophthalmology 1997; 104:844–848. 13 Cardillo JA, Alves MR, Ambrosio LE, et al. Single intraoperative application versus postoperative mitomycin C eye drops in pterygium surgery. Ophthalmology 1995; 102:1949–1952. 14 Oguz H, Basar E, Gurler B. Intraoperative application versus postoperative mitomycin C eye drops in pterygium surgery. Acta Ophthalmol Scand 1999; 77:147–150. 32 Oguz H. Inferior limbal conjunctival autograft transplantation for recurrent pterygium. Indian J Ophthalmol 2003; 51:108–109. 36 Lei G. Surgery for pterygium using a conjunctival pedunculated flap slide. Br J Ophthalmol0 1996; 80:33–34. 37 Tomas T. Sliding flap of conjunctival limbus to prevent recurrence of pterygium. Refract Corneal Surg 1992; 8:394–395. 38 Dadeya S, Malik KP, Gullian BP. Pterygium surgery: conjunctival rotation autograft versus conjunctival autograft. Ophthalmic Surg Lasers 2002; 33: 269–274. 39 Jap A, Chan C, Lim L, Tan DT. Conjunctival autorotation autograft for pterygium: an alternative to conjunctival autografting. Ophthalmology 1999; 106:67– 71. 40 Dupps WJ Jr, Jeng BH, Meisler DM. Narrow-strip conjunctival autograft for treatment of pterygium. Ophthalmology 2006; 114:227–231. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Pterygium treatment Ang et al. 313 41 Frucht-Pery J, Raiskup F, Ilsar M, et al. Conjunctival autografting combined with low-dose mitomycin C for prevention of primary pterygium recurrence. Am J Ophthalmol 2006; 141:1044–1050. In this interventional randomized prospective study, the authors compared the recurrence rates and complications in four treatment groups, namely MMC (0.2 mg/ml) alone, conjunctival autograft alone, combined MMC (0.2 mg/ml) and conjunctival autograft, as well as sodium chloride 0.9% alone. The group treated with combined conjunctival autograft and MMC had the lowest rate of recurrence. 42 Oguz H, Kilitcioglu A, Yasar M. Limbal conjunctival mini-autografting for preventing recurrence after pterygium surgery. Eur J Ophthalmol 2006; 16: 209–213. 43 Solomon A, Pires RT, Tseng SC. Amniotic membrane transplantation after extensive removal of primary and recurrent pterygia. Ophthalmology 2001; 108:449–460. 44 Ma DH, See LC, Hwang YS, Wang SF. Comparison of amniotic membrane graft alone or combined with intraoperative mitomycin C to prevent recurrence after excision of recurrent pterygia. Cornea 2005; 24:141–150. 45 Tananuvat N, Martin T. The results of amniotic membrane transplantation for primary pterygium compared with conjunctival autograft. Cornea 2004; 23: 458–463. 46 Shimazaki J, Kosaka K, Shimmura S, Tsubota K. Amniotic membrane transplantation with conjunctival autograft for recurrent pterygium. Ophthalmology 2003; 110:119–124. 47 Memarzadeh F, Fahd AK, Shamie N, Chuck RS. Comparison of de-epithelialized amniotic membrane transplantation and conjunctival autograft after primary pterygium surgery. Eye 2006; June 9 [Epub ahead of print]. 48 Nakamura T, Inatomi T, Sekiyama E, et al. Novel clinical application of sterilized freeze-dried amniotic membrane to treat patients with pterygium. Acta Ophthalmol Scand 2006; 84:401–405. 49 Kucukerdonmez C, Akova YA, Altinors DD. Vascularization is more delayed in amniotic membrane graft than conjunctival autograft after pterygium surgery. Am J Ophthalmol Feb 2007; 143:245–249. 50 Luanratanakorn P, Ratanapakorn T, Suwan-Apichon O, Chuck RS. Randomised controlled study of conjunctival autograft versus amniotic membrane graft in pterygium excision. Br J Ophthalmol 2006; 90:1476–1480. This randomized controlled study compared the efficacy of the use of amniotic membrane and conjunctival autograft in both primary and recurrent pterygia groups. Six months after surgery, amniotic membrane transplant is shown to have a higher recurrence rate than conjunctival autograft. 51 Ang LP, Tan DT, Cajucom-Uy H, Beuerman RW. Autologous cultivated conjunctival transplantation for pterygium surgery. Am J Ophthalmol 2005; 139: 611–619. 52 Golchin B, Butler TK, Robinson LP, et al. Long-term follow-up results of lamellar keratoplasty as a treatment for recurrent pterygium and for scleral necrosis induced by beta-irradiation. Cornea 2003; 22:612–618. 53 Uy HS, Reyes JM, Flores JD, Lim-Bon-Siong R. Comparison of fibrin glue and sutures for attaching conjunctival autografts after pterygium excision. Ophthalmology 2005; 112:667–671. 54 Koranyi G, Seregard S, Kopp ED. The cut-and-paste method for primary pterygium surgery: long-term follow-up. Acta Ophthalmol Scand 2005; 83:298–301. 55 Koranyi G, Seregard S, Kopp ED. Cut and paste: a no suture, small incision approach to pterygium surgery. Br J Ophthalmol 2004; 88:911–914. 56 Marticorena J, Rodriguez-Ares MT, Tourino R, et al. Pterygium surgery: conjunctival autograft using a fibrin adhesive. Cornea 2006; 25:34–36. 57 Bahar I, Weinberger D, Dan G, Avisar R. Pterygium surgery: fibrin glue versus Vicryl sutures for conjunctival closure. Cornea 2006; 25:1168–1172. Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.