Cut and Paste: No Suture, No Glue Conjunctival Autograft Technique for Pterygium Surgery - Our Experience

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1 Cut and Paste: No Suture, No Glue Conjunctival Autograft Technique for Pterygium Surgery - Our Experience Satish D Shet, Piyush Gupta, Yallappa B Bajantri, S Sahana ORIGINAL ARTICLE ABSTRACT Background: Pterygium is a common ocular disease and surgical excision with conjunctival autografting is the treatment of choice. However, recurrence is a common problem and use of sutures and glue to secure the autograft is associated with a number of adverse effects. We present an autograft technique for pterygium surgery using autologous fibrin derived from a thin layer of blood. Aim: To evaluate a sutureless, glue free conjunctival autograft technique for pterygium surgery. Setting and Design: Prospective interventional case series conducted at Karnataka Institute of Medical Sciences, Hubli. Materials and Methods: 90 eyes of 84 patients were included. After pterygium excision, the recipient bed was encouraged to achieve natural hemostasis. A thin layer of blood was allowed to cover the recipient bed and provide a source of autologous fibrin. A thin Tenon s free conjunctival autograft taken at the superotemporal limbus was placed over the recipient scleral bed without sutures or fibrin glue. Patients were followed up for any complications. Results: Follow-up period ranged from 6 to 15 months (mean 12 months). The mean surgical timing was 13 min. Graft displacement was seen in 8 cases on the 1 st post-operative day, which was repositioned. Graft retraction was seen in 2 cases at 1-month post-operative follow-up. A conjunctival granuloma was seen in one case, which was excised. No recurrences were seen during the follow-up period. Cosmesis was excellent. Conclusion: This simple technique for pterygium surgery may prevent potential adverse reactions encountered with the use of foreign materials such as sutures or fibrin glue. The technique is cost effective and requires less surgical time. KEY WORDS: Autologous fibrin, conjunctival autograft, gluefree, pterygium, sutureless INTRODUCTION Pterygium is a worldwide disease with a high incidence in tropical and subtropical areas. Primary pterygium is a fibrovascular proliferation over the nasal cornea, probably resulting from limbal stem cell deficiency. [1] The exact cause of pterygium is not well-understood. However, long-term exposure to sunlight, especially ultraviolet rays, and chronic eye irritation from dry, dusty conditions seem to play an important role. [2] Histopathologically it shows degenerative and hyperplastic changes. [3,4] An electron microscopic study of the cap areas of several pterygia shows the presence of active fibroblasts in the natural tissue planes surrounding Bowman s Quick Response Code: Access this article online Website: *** layer. The hypothesis is that the fibroblasts originate in the limbal connective tissue. They advance in the cornea above and below Bowman s membrane, destroying the latter and a variable amount of superficial corneal stroma. [5] Pterygium is a nonmalignant, slow growing, wing-shaped proliferation of fibrovascular tissue arising from subconjunctival tissue, which may extend over the cornea, thereby causing visual disturbances. [6] India, a tropical country where heat and dust are synonymous with the environment, has a high prevalence of pterygium. Surgical removal is the treatment of choice. [7] However, simple excision of the pterygium has a very high rate of recurrence, ranging from 30% to 70%. [8] To overcome this, a wide Department of Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India Address for correspondence: Dr. Satish D Shet, Department of Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India. Phone: , satshet@rediffmail.com Journal of Vision Sciences/May-Aug 2015/Volume 1/Issue 2 3

2 variety of surgical modifications have been used. The adjunctive therapies include mitomycin-c, beta irradiation, human amniotic membrane grafting, and autologous conjunctival grafting. [9] The transplantation of conjunctival or conjunctivolimbal autograft was reported to be the most effective method of lowering recurrence rate (2~9%) and complications. [10-12] Currently available techniques for securing the conjunctival autograft include sutures and fibrin glue. Both these techniques are associated with some complications ranging from post-operative discomfort with sutures to a rare risk of viral transmission with fibrin glue. [7] In developing countries, the cost is also a concern when using commercially available fibrin glue. as achieving a smooth scleral bed for autograft is difficult due to the dense fibrous adhesions in these cases. Written informed consent was obtained from all the patients. Surgical technique (Figures 1 and 2) Peribulbar anesthesia with a Von lint block was given. Step 1: Preparation of the graft (Figure 1a and b) The graft was prepared before pterygium excision so as to allow quick placement of graft over a fresh layer of blood. Graft size was decided based on the grade of pterygium [15] assuming that the gap between In this study, we describe a cost-effective method of achieving conjunctival autograft adherence in pterygium surgery using autologous fibrin derived from blood, without the use of sutures or commercially available fibrin glue. Some recent studies [13,14] have shown the success of this procedure. Here, we present a large case series of patients who underwent pterygium excision with conjunctival autograft with this technique. a b MATERIALS AND METHODS It was a prospective, interventional case series conducted at the Ophthalmology Department of a Karnataka Institute of Medical Sciences, Hubli, Karnataka, India. Ninety eyes of 84 patients with primary pterygium who presented between February 2011 and March 2013 were included. The study was approved by the Local Ethics Committee, and the trial was registered with the Clinical Trial Registry India (CTRI/01/2012/02366) during the study. Inclusion and exclusion criteria Patients aged between years who had a growing primary pterygium which had invaded more than 1 mm onto the cornea were included. This age group was chosen as patients were more likely to comply with instructions and observe precautions. Patients with a recurrent pterygium, ocular surface pathology or infection and major systemic illnesses like collagen vascular disorder, uncontrolled diabetes mellitus were excluded. Recurrent pterygium cases were excluded c Figure 1: (a) Irrigation of the grft site with trypan blue, (b) preparing Tenon s free limbal based conjunctival autograft, (c) avulsion of pterygium using colibri forceps, (d) rupture of capillaries to provide autologous fibrin a c Figure 2: (a and b) Sliding of the conjunctival autograft, (c) instillation of povidone iodine, (d) gentle closure of lids with hoskin s forceps d b d Journal of Vision Sciences/May-Aug 2015/Volume 1/Issue 2 4

3 graft-host junction would be epithelized in a few days. Table 1 shows the grading of pterygium. The superotemporal area was irrigated with Trypan Blue (Rhex-Id, Appasamy Associates, India) (Figure 1a). It has two advantages. Trypan Blue stains the epithelial surface and hence allows for easier identification of the graft side. Furthermore, incisions can be made out easily due to conjunctival surface staining. Trypan Blue is easily available as it is routinely used in cataract surgery. A Castroviejo caliper was used to measure the size and extent of the autograft and to mark four points over the stained conjunctiva, two at the posterior limbus and two corresponding points behind the limbus at precalculated distances based on the grade of the pterygium, by giving a firm pressure with the tip of the instrument over these points. The graft was rectangular in shape, and the average size of the graft was 5 mm 7 mm. Tenon s free limbal based conjunctival autograft (Figure 1b) was prepared without separating the limbal attachment of the graft. Step 2: Excision of the pterygium (Figure 1c) The head of the pterygium was excised using the avulsion technique with a Colibri forceps and any remnant pterygium tissue over the cornea was removed with a Tooke corneal knife. The body of the pterygium and subconjunctival tissue was excised with corneal scissors leaving behind a bare sclera. Step 3: Providing source of autologous fibrin (Figure 1d) A thin layer of fresh blood is required over the bare sclera to provide autologous fibrin. After pterygium excision, if no blood was evident at the recipient bed, small perforating veins or capillaries were deliberately ruptured with a Hoskin s forceps. Any excess bleeding was cauterized. Step 4: Sliding the graft from the donor to the recipient site (Figure 2a and b) At this stage, the graft was separated from the limbus and stretched evenly over the bare scleral bed with the help of the closed smooth jaws of a McPherson forceps. This ensured maximum surface area contact of the autograft with the sclera bed akin to spreading bed linen without folds over a mattress. A McPherson forceps has smooth jaws, and when both jaws are apposed, it helps in even stretching of the graft without Table 1: Approximate graft size depending on grade of pterygium [15] Grade 1 Grade 2 Grade 3 causing any damage. After positioning the graft well, it was ensured that any residual bleeding did not lift the graft. Any excess bleeding was controlled with direct compression using a Weck-cel sponge and McPherson forceps. A drop of povidone iodine was instilled at the end of surgery and the speculum was gently removed (Figure 2c). Eyelids were closed with the help of a Hoskin forceps while taking care not to dislodge the graft (Figure 2d). An eye pad was placed overnight. Post-operative period Antibiotic-steroid drops (chloramphenicoldexamethasone) were prescribed 6 times/day for 1 week, and then steroids were given in tapering doses over the next 2-3 weeks. Dexamethasone was preferred as it does not form precipitates like prednisolone. No eye ointments were used. Patients were given instructions not to rub the eye and report to the hospital staff in case of symptoms such as pain, watering or irritation at the earliest so that they could be examined for graft dislocation or loss of autograft. Follow-up Patients were followed up at 1 day, 1 week, 1 month and then at 2, 3, 6, 9, 12, and 15 months after surgery. Primary outcome measures included graft dislocation and pterygium recurrence. Secondary outcome measures included patient comfort and surgical time 30% of patients were lost to follow-up after 6 months. A majority of them were reluctant to come for follow-up since they had no further complaints. RESULTS (TABLE 2) Pterygium extends <2 mm over the cornea (graft area approximately mm 2 ) Pterygium extends 2 4 mm over the cornea (graft area approximately mm 2 ) Pterygium extends >4 mm over the cornea (graft area approximately mm 2 ) All the surgeries included in the study were performed by a single experienced surgeon (S.S). During the study period, 48 males and 36 females underwent sutureless, glue free (SGF) conjunctival autograft for pterygium. Six patients (all males) had bilateral Grade 3 nasal pterygium. Mean age at surgery was 34.6 years ± standard deviation Journal of Vision Sciences/May-Aug 2015/Volume 1/Issue 2 5

4 Table 2: Results Mean (age) Mean surgical timing was 13 min (10-17 min). Graft displacement was seen in 8 cases (9%) on the 1 st post-operative day. The graft was repositioned with a Hoskin forceps under topical anesthesia with the patient sitting in front of a slit lamp. No graft displacements were noticed subsequently following repositioning the graft. Graft retraction was seen on the 1 st post-operative day in 14 eyes (15.5%). At 1-month follow-up, graft retraction was seen only in 2 cases (2.2%) which suggested that the exposed area epithelized adequately on follow-up in most cases, without compromising the surgical or cosmetic results. No recurrences were seen until the last follow-up in any of the cases. The only complication noted was conjunctival granuloma in 1 case (who had Grade 2 pterygium pre-operatively) at the nasal side of the host-graft junction at 1 month, which was excised without compromising the surgical result. Cosmesis was excellent in all cases. No other significant post-operative complications occurred that warranted further treatment. DISCUSSION 34.6 years Male: Female 48:36 Laterality (RE: LE) 52:38 Grade of pterygium Mean surgical timing Mean follow up Graft displacement at 4 h post operative (on 1 st day) (%) Grade 1 41 eyes Grade 2 36 eyes Grade 3 13 eyes 13 min (10 17 min) 12 months (6 15 months) 8 (9) Graft retraction on the 1 st day (%) 14 (15.5) Graft retraction at 1 month (%) 02 (2.2) Recurrence None Sutures and fibrin glue have been used to secure conjunctival autografts. The use of sutures to secure the autograft prolongs the operating time and is also associated with drawbacks, such as post-operative discomfort and suture-related complications. The presence of sutures may lead to prolonged wound healing and fibrosis [7,16] and more chances of pyogenic granuloma formation. Fibrin glue as an alternative for suturing for conjunctival closure, has been used in pterygium surgery because of its advantages in decreasing operating time, decreasing post-operative discomfort, and avoiding suture-related complications, but it is associated with the risk of hypersensitivity reactions and viral transmission. [17] Virus removal and inactivation procedures are included in the manufacturing process, but they may be of limited value against non-enveloped viruses such as hepatitis A virus and parvovirus B19. [18] The cost of commercially available fibrin glue is also a concern in developing countries. Recurrence is the most important concern in pterygium surgery as it is a source of frustration for both patients and surgeons. It is defined as the presence of fibrovascular tissue re-growth extending beyond the surgical limbus onto the clear cornea. [18] Recurrences were noted in other case series of SGF graft procedure in the comparative tabulated form as per Table 3. We did not have any recurrence in our case series. Long-term follow-up is necessary to study recurrence rates. However, a study by Alpay et al. [19] comparing four commonly used techniques for pterygium surgery reported the mean time for the appearance of any complication including recurrence is 4-6 months. [20] We found that a graft size bigger than the recipient bed (as used in the standard technique) is not required because sutures or fibrin glue are not used, and some amount of conjunctival retraction is expected. Irrespective of the graft size, some amount of gap is expected at graft-host junction. Specifically, the risk of graft retraction as described by Tan [21] appears to be no greater, with no suture no glue technique, as long as a meticulous dissection of the subepithelial graft tissue is respected. We too agree with the postulate that as there is even tension across the whole of the graft interface, and no direct tension on the free graft edges, chances of graft adherence are more with reduced stimulus for subconjunctival scar tissue to form. [21] Our study of 90 eyes is the largest case series using SGF conjunctival autograft technique that has been reported so far. We have made an effort to compare the results of similar case studies with ours (Table 3). We have found a similar rate of graft displacement, although the rate of graft retraction and recurrence of pterygium is lesser in comparison to others. techniques Journal of Vision Sciences/May-Aug 2015/Volume 1/Issue 2 6

5 Table 3: Comparison of results with autograft SGF studies Parameters de Wit et al. [17] (%) Singh et al. [13] (%) Malik et al. [14] (%) Our study (%) Total number of cases Graft displacement 1 (10) 2 (5) 8 (9) Graft retraction 1 (10) 3 (7.5) 2 (2.2) Recurrences None 1 (10) 1 (2.5) None (0) SGF: Sutureless glue free of pterygium surgeries. We have not encountered any recurrences in our large case series. Further follow-up is necessary to report any recurrences. There were some limitations in this study. Evaluating pain is not easy since patients report different sensitivity for the same stimulus. In addition, they have different capacity to withstand the pain. In this study, pain reported by the patients was not objectively compared with the patients in whom sutures or fibrin glue were used. However, subjectively patients did not complain of significant pain in the post-operative period with this technique. Most importantly, the operating time, post-operative symptoms, recurrence and complication rate of the above-described technique appears to be significantly less as compared to conventional suture and glue techniques with a similar follow-up duration. [7,16,17,22] CONCLUSION This simple technique for pterygium surgery may prevent potential adverse reactions encountered with the use of foreign materials such as suture or fibrin glue. Surgeons should consider this technique to obtain a better surgical outcome with good cosmesis, minimal chances of recurrences, lesser surgical time, less instrumentation, and early rehabilitation to make it affordable to more patients and the community at large. REFERENCES 1. Prabhakar SK. Safety profile and complications of autologous limbal conjunctival transplantation for primary pterygium. Saudi J Ophthalmol 2014;28: Austin P, Jakobiec FA, Iwamoto T. Elastodysplasia and elastodystrophy as the pathologic bases of ocular pterygia and pinguecula. Ophthalmology 1983;90: Saw SM, Tan D. Pterygium: Prevalence, demography and risk factors. Ophthalmic Epidemiol 1999;6: Kase S, Takahashi S, Sato I, Nakanishi K, Yoshida K, Ohno S. Expression of p27(kip1) and cyclin D1, and cell proliferation in human pterygium. Br J Ophthalmol 2007;91: Cameron ME. Histology of pterygium: An electron microscopic study. Br J Ophthalmol 1983;67: Ashok G, Toukhy Essam EL, Nassaralla Belquiz A, Sunil M. Surgical and Medical Management of Pterygium. India: Jaypee Brothers Medical Publication; p Koranyi G, Seregard S, Kopp ED. Cut and paste: A no suture, small incision approach to pterygium surgery. Br J Ophthalmol 2004;88: Hirst LW. The treatment of pterygium. Surv Ophthalmol 2003;48: Pan HW, Zhong JX, Jing CX. Comparison of fibrin glue versus suture for conjunctival autografting in pterygium surgery: A meta-analysis. Ophthalmology 2011;118: Ma DH, See LC, Liau SB, Tsai RJ. Amniotic membrane graft for primary pterygium: Comparison with conjunctival autograft and topical mitomycin C treatment. Br J Ophthalmol 2000;84: Sánchez-Thorin JC, Rocha G, Yelin JB. Meta-analysis on the recurrence rates after bare sclera resection with and without mitomycin C use and conjunctival autograft placement in surgery for primary pterygium. Br J Ophthalmol 1998;82: 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: Singh PK, Singh S, Vyas C, Singh M. Conjunctival autografting without fibrin glue or sutures for pterygium surgery. Cornea 2013;32: Malik KP, Goel R, Gupta A, Gupta SK, Kamal S, Malik VK, et al. Efficacy of sutureless and glue free limbal conjunctival autograft for primary pterygium surgery. Nepal J Ophthalmol 2012;4: Kanski JJ. Clinical Ophthalmology. 6 th ed. New York: Butterworth-Heinemann/Elsevier; Allan BD, Short P, Crawford GJ, Barrett GD, Constable IJ. Pterygium excision with conjunctival autografting: An effective and safe technique. Br J Ophthalmol 1993;77: de Wit D, Athanasiadis I, Sharma A, Moore J. Sutureless and glue-free conjunctival autograft in pterygium surgery: A case series. Eye (Lond) 2010;24: Gröner A. Pathogen safety of plasma-derived products - Haemate P/Humate-P. Haemophilia 2008;14 Suppl 5: Alpay A, Ugurbas SH, Erdogan B. Comparing techniques for pterygium surgery. Clin Ophthalmol 2009;3: Journal of Vision Sciences/May-Aug 2015/Volume 1/Issue 2 7

6 20. Markovich AL, Bahar I, Srinivasan S, Slomovic AR. Surgical management of pterygium. Int Ophthalmol Clin 2010;50: Tan D. Conjunctival grafting for ocular surface disease. Curr Opin Ophthalmol 1999;10: Sebban A, Hirst LW. Pterygium recurrence rate at the Princess Alexandra Hospital. Aust N Z J Ophthalmol 1991;19: How to cite this article: Shet SD, Gupta P, Bajantri YB, Sahana S. Cut and paste: No suture, no glue conjunctival autograft technique for pterygium surgery - Our experience. J Vis Sci 2015;1(2):3-8. Financial Support: None; Conflict of Interest: None Journal of Vision Sciences/May-Aug 2015/Volume 1/Issue 2 8