In this retrospective cohort study, which is the first to date comparing sutureless CAG and CLAG fixation for pterygium surgery, the latter showed a longer recurrence-free time and an overall reduced rate of recurrence and complications.
Pterygium excision with CAG placement has been established over the years as the gold standard of pterygium surgery, and it is currently used as the control technique in most evaluations of new surgical techniques.2–6,8 Several studies have shown the effectiveness of including limbal tissue in the conjunctival graft for reducing the risk of pterygium recurrence,12–16,18,19,23 but very few comparisons of CLAG versus CAG are available, and all of them use the sutures for the graft fixation.13,15 We found a significantly lower recurrence rate of pterygium in the overall CLAG group at one year after surgery, with approximately 4%, compared to the 17% of CAG. This was similar in the subgroup analysis of primary pterygium and in the overall results at the end of the follow-up. In the subgroup of recurrent pterygium, the recurrence rate was always lower for CLAG (13% vs. 33% of CAG), but it was not statistically significant (p = 0.17). This was probably due to the smaller sample size (N = 36) if compared to that one of primary pterygium (N = 229). These results are congruent with those previously reported in the literature,6,13,15 and might be due to the fact that conjunctival grafting is not enough to solve one of the most relevant causes of pterygium, that is limbal insufficiency.1,5 Multivariate analysis further confirmed this trend, as CLAG was independently associated with a reduced risk of recurrence compared with CAG.
To the best of our knowledge, this is the first study to report pterygium excision with CLAG versus CAG using exclusively sutureless graft fixation of the conjunctival-limbal autograft to the sclera. Indeed, all previous assessments used sutures13,15, whereas current trends favor the use of a sutureless technique (i.e., fibrin glue) because it was seen to reduce operating times and postoperative patient discomfort, resulting in greater cost-effectiveness than sutures alone.9,10,24 It is therefore possible that the combination of the autograft of healthy limbal stem cells and a sutureless fixation could be more efficient in reducing the recurrence rate than their separate use.
Importantly, our data showed, for the first time, that CLAG and CAG had an average time to recurrence of approximately nine and five months, respectively. For CLAG, the first recurrences appeared from the sixth postoperative month, while for CAG, they appeared almost immediately from the first month. It is probable that the use of limbal grafts could promote better restoration of the right limbal anatomy and reduce the risk of early recurrences, as shown in the other techniques involving this tissue (i.e., Simple Limbal Epithelial Transplantation, SLET).17,25 When considering the risk of postoperative complications, CLAG was shown to be safer than CAG. Epithelial defects occurred only once in the CLAG group (1% vs. 7% in CAG) and were easily managed with bandage contact lens application. The major concern with Limbal surgery, which is a limbal stem cell deficiency induced at the site of the limbal graft, was not observed in the present study or in previous studies.13,15,17–19
Even though CAG is a safe and effective technique, still preferred by most surgeons,2,3,5 CLAG was previously shown to reduce the risk of recurrence,13,15,16,18,19 and the present assessment also found that CLAG increases the time to potential recurrence, essentially preventing recurrences within 6 months after surgery. Moreover, since the surgical time was comparable to that of CAG and the safety profile was even more favorable, our study suggests that CLAG could have a better cost-effectiveness profile, reducing the risk of recurrence and complications without additional cost.
This was the largest cohort study to date to employ the sutureless technique, which assessed not only the recurrence rate but also the time free from recurrence. The outcomes were measured during a follow-up period of at least one year, performing complete clinical examinations, and systematically recording all complications. Nevertheless, this study has limitations that must be mentioned. First, the retrospective nature of data collection may have introduced bias, although it was ascertained that clinical records were collected consistently during the entire study period. Second, loss to follow-up involved 15% of the initial procedures; however, this could hardly bias our estimates because it was balanced across the two groups: 7% for CLAG and 8% for CAG.
In conclusion, this study joins the body of evidence in favor of CLAG over CAG,13,15, as it not only reduced the risk of recurrence, but also guaranteed a longer disease-free time, and ultimately supports CLAG as the most reasonable option whenever the decision is to treat the pterygium with an autologous graft.16,18,19 However, as the current surgical approaches are still far from 100% effectiveness,6–8 further studies are necessary to deeply understand the pathogenesis of the disease and the best surgical management.