Long-term analysis of an unconventional way of doing double-head pterygium excision.

AIM: The aim of the study is to describe an unconventional technique of vertically split conjunctival autograft (CAG) for primary double-head pterygium and its long-term outcome.
MATERIALS AND METHODS: This was a retrospective, noncomparative, interventional case series of 95 eyes of 95 patients, who underwent vertical, split CAG surgery without maintaining limbus-limbus orientation for primary double-head pterygium from January 2013 to January 2017. All patients were reviewed for recurrence in their follow-up period.
RESULTS: The mean follow-up was 14.12 ± 9.42 months. The baseline characteristics included 44 males and 51 females, with a mean age of 56.24 ± 10.03 years. The only significant complication was recurrence rate of 2.10% (2 eyes out of 95). The most common secondary outcome was graft edema (36.84%, 35 eyes out of 95), which resolved without any intervention. The other outcomes such as graft retraction (12.63%), Tenon's granuloma (1.05%), and subconjunctival hemorrhage (34.73%) were also recorded.
CONCLUSION: Unconventional vertical split CAG without maintaining limbus-limbus orientation has convincing results in treating double-head pterygium with lower recurrence rate. Copyright:

Introduction

Pterygium is a pinkish fibrovascular growth on the cornea of the eye.[1] The exact cause is unknown but partly related to long-term exposure of ultraviolet light and dust.[2] The frequency ranges from 1% to 33% in various parts of the world, but commonly seen in India and African continent which is closer to the equator.[3] Dolezalová reported an incidence of double-head pterygium in the same eye to be 2.5%.[4] It is an already established fact that conjunctival autograft (CAG) is the gold standard in the management of primary pterygium;[5] however, it may be inadequate to cover the bare scleral defect in a double-head pterygium.

We herein report a unique way of excising double-head pterygium using vertically split CAG without maintaining limbus–limbus orientation.

Materials and Methods

A total of 95 eyes of 95 patients which underwent primary double-head pterygium excision with vertical split CAG without limbus–limbus orientation from January 2013 to January 2017 were reviewed retrospectively at a tertiary eye care hospital in South India. Preoperative data included patient's age, sex, and visual acuity before and after surgery, ocular medical and surgical history, surgical technique, and complications. All the surgeries were performed by one surgeon. Pterygium was graded according to the corneal involvement (Grade 1: crossing limbus; Grade 2: midway between limbus and pupil; Grade 3: reaching up to pupillary margin; and Grade 4: crossing pupillary margin). Only up to Grade 3 pterygium was included in the study with exclusion of Grade 4 and recurrent pterygium. The study was approved by the institutional ethics committee and adhered to the tenets of the Declaration of Helsinki.

Surgical procedure

Preoperative image of double-head pterygium in the left eye is shown in Figure 1. After preoperative sterile painting and draping, 0.5% proparacaine HCl (Aurocaine, Aurolab, Tamil Nadu, India) was used as a topical anesthesia. The head of nasal pterygium was avulsed using a toothed forceps and an iris spatula. The underlying fibrovascular tissue was then excised using conjunctival forceps followed by scraping of bed for any residual tissue using crescent blade. Adequate wet-field cautery was used to achieve hemostasis. Similar step was performed for the temporal pterygium. The superior bulbar conjunctiva was selected as donor site. Balanced salt solution was injected subconjunctivally with a 26G needle, which helped in good dissection of conjunctiva from Tenon's capsule. After giving a small nick incision at the forniceal end, a thin conjunctival graft of adequate size was fashioned. Starting from forniceal end, the graft was split vertically into two halves till the limbus was reached [Figure 2a]. Tenon's capsule was separated meticulously for each graft. For successful graft take-up, thin graft with meticulous dissection of Tenon's capsule is required.[6] The nasal graft was then excised from its base using Vannas scissor, and without changing the orientation, the graft was placed on bare scleral defect of the nasal side [Figure 2b]. With epithelium side up, split conjunctival nasal autograft was secured with fibrin glue Tisseel VH (Baxter AG, Vienna, Austria). Similar procedure was followed for temporal half CAG [Figure 2c]. Here, limbus–limbus orientation was not maintained and complete covering of bare area was ensured [Figure 2d]. The eye was patched overnight. Postoperatively, topical 0.5% moxifloxacin HCl, topical 0.5% loteprednol etabonate, and tear substitute 0.5% carboxymethylcellulose were started 6 times daily for the first week and then tapered gradually. Patients were examined on the postoperative day 1 and later asked for follow-up after 1 week [Figure 3a], 6 weeks [Figure 3b], 6 months, and 1 year [Figure 4] thereafter. Patients with a follow-up of less than 6 months were not included in the study. Recurrence was defined as fibrovascular tissue in the growth of 1.5 mm or more beyond the limbus onto the clear cornea with conjunctival dragging as described by Singh et al.[7]

Figure 1

Double-head pterygium preoperatively

Figure 2

(a) Vertical split conjunctival graft technique, (b) nasal split graft secured with glue without limbus–limbus orientation, (c) temporal split graft secured with glue without limbus–limbus orientation, (d) both grafts in situ without limbus–limbus orientation

Figure 3

(a) One-week postoperative, (b) 6 weeks postoperative

Figure 4

One-year follow-up

Statistical analysis

Recurrence of pterygium was the primary outcome, whereas other complications such as Tenon's granuloma, graft retraction, graft edema, and subconjunctival hemorrhage were considered as other outcome variables. Descriptive analysis for quantitative variables was done using mean and standard deviation.

Results

On retrospective analysis of 95 eyes with primary double-head pterygium operated by this technique without maintaining limbus–limbus orientation, the following results were obtained. The total number of males was 44 and females was 51, with a mean age of 56.24 ± 10.03 (years). The mean follow-up was 14.12 ± 9.42 (months). Patients with a follow-up of less than 6 months were not included in the study. A total of 2.10% (2 eyes out of 95) had recurrence and both were temporal site recurrence. 36.84% (35 eyes out of 95) had postoperative edema. Similarly, 34.73% (33 eyes out of 95) had subconjunctival hemorrhage. 12.63% (12 eyes out of 95) had graft retraction in the postoperative period, and 1.05% (1 eye out of 95) developed Tenon's granuloma. Table 1 shows the percentage of various outcome of this study.

Table 1

Outcomes of this study

Complications	n=95, n (%)
Edema	35 (36.84)
SCH	33 (34.73)
Retraction	12 (12.63)
Recurrence (total)	2 (2.10)
Tenon’s granuloma	1 (1.05)

SCH: Subconjunctival hemorrhage

Discussion

One of the major complications postpterygium surgery is recurrence, which usually occurs within 6 months.[8] The main aim is to minimize the recurrence rate along with better cosmetic outcomes. In this technique, we had used vertically split CAG from superior quadrant and secured the graft using fibrin glue without maintaining limbus–limbus orientation on bare scleral defects. There is no dearth of literature as far as the way of treating double-head pterygium ranging from vertical split CAG with limbus–limbus orientation, split CAG with horizontal graft, superior and inferior bulbar CAG, and amniotic membrane transplantation (AMT), but none of them has overall acceptance. Conventional bare sclera technique is not done routinely because of high recurrence rate.[9] Use of various adjuncts such as beta-irradiation or thiotepa eye drops, anti-mitotic drugs (mitomycin C and 5-fluorouracil), fibrin glue, and AMT has been described to prevent recurrence.[10] Amniotic membrane is costly and requires preservation and availability is an issue sometimes. Previous studies have reported higher recurrence rate with the use of AMT compared to conjunctival autografting.[11] Various complications of mitomycin-C have been noted such as punctuate keratopathy, scleral melt, and corneal melting.[12] Use of fibrin glue for securing graft gives advantages of easy fixation and better postoperative comfort.[13] The author has already published this similar technique where sutures were used instead of glue for securing the two grafts and had excellent results.[14] In this technique, we have used glue instead of sutures and had very comparable postoperative recurrence rate of 2.01% (2 eyes out of 95) with much better cosmetic outcomes. Furthermore, various suture-related complications published in the literature was also avoided.[1516] In this study, two eyes with temporal site recurrence had excessive graft retraction in the early postoperative period, which could be due to inclusion of Tenon's in the graft and can be reduced by meticulous dissection.[16] The remaining 12 eyes with retraction resolved at 6 weeks without any intervention. Very recently, a new Pterygium Extended Removal Followed by Extended Conjunctival Transplant technique for double-head pterygium was published by Hirst and Smallcombe with no recurrence rate at 1-year follow-up in 20 eyes.[17] Using other procedures, previously published studies for primary double-head pterygium have shown varying degrees of recurrence that ranged from 0% to 35%.[1417181920] Graft edema was the most common outcome of our study, as reported earlier by Mutla et al.[21] Graft edema subsided without any intervention at the end of 1–2 weeks and can be prevented by avoiding excessive handling of the graft. We had 1.05% of Tenon's granuloma (1 eye out of 95), which may be due to friction of the exposed Tenon's tissue with upper lid during blinking eventually, leading to granuloma formation.[22] The role of limbal stem cells in acting as a barrier between the conjunctiva and corneal epithelium and its destruction, leading to growth of conjunctival tissue on to the cornea,[23] has been reported in the past. However, in our technique, adequate size graft and enough to cover the bare sclera defect without maintaining limbus–limbus orientation and along with usage of fibrin glue have better cosmetic outcome and lower recurrence rate.

Table 2 shows the results of different techniques of double head pterygium surgery and their postoperative outcomes.

Table 2

Comparison of outcomes with published literature

Authors	Pterygium type	Number of eyes (n)	Surgery technique	Mean follow-up (months)	Recurrence rate (%)	Granuloma (%)	SCH (%)	Edema (%)
This study	Primary	95	Vertical SCG with glue without limbus-limbus orientation	14.12±9.42	2/95 (2.10)	1/95 (1.05)	33/95 (34.73)	35/95 (36.84)
Kodavoor et al.[14]	Primary	87	Vertical SCG with sutures without limbus-limbus orientation	17.28±10.28	3/87 (3.45)	3/87 (3.45)	32/87 (36.78)	37/87 (42.52)
Hirst and Smallcombe[17]	Primary	20	PERFECT technique	12	0/20 (0)	-	-	-
Solomon et al.[18]	Primary	11	Extensive pterygium excision with AMT	12.8±4.3	1/11 (9)	-	-	-
Wu et al.[19]	Primary	20	Conjunctival rotational autograft combined with CAG	22.6	7/20 (35)	-	9/20 (45)	-
Maheshwari[20]	Primary	7	SCG with limbus-limbus orientation on nasal side	17.7±6.0	0/7 (0)	-	-	-

†AMT: Amniotic membrane transplant, ‡PERFECT: Pterygium Extended Removal Followed by Extended Conjunctival Transplant, SCG: Split conjunctival graft, CAG: Conjunctival autograft, SCH: Subconjunctival hemorrhage

Conclusion

Our study had certain limitations of being nonrandomized and retrospective in nature. This technique using glue has near similar results compared to use of sutures, as already published by us in previous literature Use of fibrin glue in this technique improves further comfort and outcome. Nevertheless, the probability success of this technique remains to be tested in cases of recurrent pterygium.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.