Abstract
Purpose :
Conventional therapies for potentially blinding corneal disorders like burns, ulcers and scars have several limitations. We aimed to clinically validate the findings of previous animal studies, which had indicated that application of limbal stromal stem cells (LSSC) to the wounded corneal surface promoted corneal stromal regeneration, prevented fibrosis and restored corneal transparency.
Methods :
In this pilot-clinical trial, one-clock hour wide limbal biopsies were obtained from donor eyes. The LSSC were isolated ex-vivo using a previously standardized xeno-free cultivation technique. The Funderbugh technique of LSSC delivery involved: (i) debridement of the corneal epithelium using a dry sponge; (ii) mixing 0.5 million LSSC in 0.05ml of the fibrinogen component of commercially available fibrin sealant and layering it over the bared corneal stroma; (iii) adding 0.05ml of the thrombin component and allowing the two components to gel; and (iv) placing a bandage contact lens on the eye. Patients in the study group were prescribed prophylactic topical antibiotics without any corticosteroids. Patients in the control group received the standard medical therapy, including topical corticosteroids, along with debridement and fibrin glue but without the cells.
Results :
The study group included 5 eyes each with acute corneal burns and sterile non-healing ulcers, which received allogeneic LSSC; and 5 eyes with chronic post-infectious scars, which received autologous LSSC. The control group was matched both in terms of numbers and baseline characteristics. At 4 weeks, when compared to controls, the eyes receiving LSSC, irrespective of the source, showed: (i) greater improvement in best-corrected visual acuity (P=0.003); (ii) faster corneal epithelization (p=0.002); (iii) better corneal clarity, evaluated both clinically (P=0.012) and on scheimpflug imaging (P<0.0001); and lesser corneal vascularization (p<0.0001). None of the 15 eyes receiving LSSC required a second surgical intervention as compared to 6 of 15 (40%) eyes in the control group (p=0.017).
Conclusions :
The Funderburgh technique of delivering autologous and allogeneic LSSC was effective in enhancing vision, promoting corneal epithelization, improving corneal clarity, reducing corneal scarring and thus obviating the need for corneal transplantation in eyes with corneal burns, ulcers and scars.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.