Safety And Feasibility Of Subconjunctival Injection Of Mesenchymal Stem Cells For Acute Severe Ocular Burns: A Single-Arm Study

Purpose: To investigate the safety and feasibility of topical injection of bone marrow derived mesenchymal stem cells (BM-MSCs) in acute severe ocular burns. Methods: In this open-label,single-arm study, subconjunctival injection of allogenic BM-MSCs combined with standard treatment was given to 16 patients with acute severe ocular burns (Dua's grade IV to VI) within 2 weeks after injury. The primary outcome was efficacy rate which referred to the proportion of complete corneal epithelialization patients without perforation. The secondary outcome was safety, visual acuity, the number of symblephara, and elevated intraocular pressure. Results: One patient was lost to follow-up. During the follow-up period, no corneal perforation was developed. Complete corneal epithelialization was noted 8 (ranged 4-10 weeks) weeks after treatment in 13 eyes (81.3%). The efficacy rate was 87.5% (95% confidence interval, CI: 61.7-98.4). Hypopyon was detected and later well controlled in 1 eye. Partial or total limbal stem cell deficiency (LSCD) was noted in all eyes. Improvement of visual acuity was achieved in 5 out of 16 eyes (31.3%). Seven eyes' visual acuity was reached 0.1. Symblepharon with varied severity was noted in 5 eyes. Two eyes had elevated intraocular pressure. Conclusions: This study confirms the safety of subconjunctival injection of BM-MSCs as an innovative and convenient procedure in ocular burns. The overall result is promising considering the absence of perforation, the low severity of symblepharon and visual acuity improvement.