The aim of this study is to investigate the clinical efficacy and safety of subconjunctival injection of 5-fluorouracil (5-FU) adjacent to the lesion for the treatment of early-stage, active recurrent pterygium, and observe its potential to reverse early lesions that have already invaded the cornea.

Data were collected from 6 patients (6 eyes) diagnosed with early recurrent pterygium and treated at the Department of Ophthalmology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology from December 2021 to July 2025. The cohort included 1 male (1 eye) and 5 females (5 eyes) with a mean age of (34.8±5.5) years (ranging from 25 to 40 years). All patients received outpatient subconjunctival injections of 5-FU (0.2 to 0.3 ml per session) adjacent to the lesion, administered once weekly until the lesion entered a quiescent state. Before and after treatment regarding the degree of congestion under slit-lamp microscopy, the extent of corneal invasion, and neovascularization were observed; epithelial morphology under in vivo confocal microscopy (IVCM); and ocular irritation symptoms including foreign body sensation, congestion sensation, photophobia, and tearing assessed using the visual analogue scale (VAS). The patient′s age, recurrence time, injection frequency, and VAS score were described using ±s. Categorical data such as gender and efficacy assessment were described using frequency and percentage (%).

The postoperative recurrence time for the 6 patients (6 eyes) was a mean of (4.2±1.0) months (ranging from 3 to 5.5 months). All patients completed the treatment and follow-up. The 6 patients (6 eyes) received 2 to 4 injections, with a mean of (2.8±0.8) injections; the follow-up period ranged from 8 to 12 months, with a mean follow-up duration of (9.8±1.5) months. All 6 patients (6 eyes) in this study showed a response to treatment, yielding a total effective rate of 100%. Among them, 5 patients (5 eyes) achieved remission, accounting for 83.3%; objectively, the conjunctival epithelium and neovascularization of the recurrent pterygium invading the cornea completely regressed and remained stable during the follow-up period; subjective symptoms essentially disappeared, with VAS scores ≤0.5. One patient (1 eye) showed improvement, accounting for 16.7%; objectively, the degree of congestion and tissue thickness significantly improved compared to baseline; the pterygium head did not invade further into the cornea during follow-up. Before treatment, the VAS scores of the 6 patients (6 eyes) ranged from 2 to 6 scores, with a mean of (4.0±1.4) scores. After treatment, at the last follow-up, VAS scores ranged from 0 to 0.5 scores, with a mean of (0.17±0.26) scores, indicating that ocular irritation symptoms were significantly improved or resolved in all patients. The best corrected visual acuity of the patients remained at 1.0 before and after treatment. Pre-treatment intraocular pressure ranged from 12.0 to 18.7 mmHg (1 mmHg=0.133 kPa), with a mean of (15.9±2.4) mmHg; post-treatment intraocular pressure ranged from 13.0 to 19.0 mmHg, with a mean of (16.1±2.3) mmHg, both within the normal range. IVCM showed that the highly reflective proliferative epithelium observed before treatment returned to a normal morphology after treatment. During the follow-up period, none of the 6 patients (6 eyes) experienced severe complications such as corneal epithelial defects, corneal stromal melting, scleral softening, or infection.

For early-stage active recurrent pterygium, subconjunctival injection of 5-FU adjacent to the lesion is a safe, effective, and minimally invasive treatment option. This therapy can not only effectively inhibit disease progression and significantly improve patient symptoms but also induce regression in early lesions that have already invaded the cornea, providing a new interventional strategy to avoid reoperation in clinical practice.