Patient reported outcomes before and following ex vivo cultured autologous limbal stem cell transplantation for total unilateral limbal stem cell deficiency

Abstract

Purpose: There is little published data concerning subjective outcomes before and following therapy for limbal stem cell deficiency (LSCD). Purpose: to assess patient reported outcomes using a variety of instruments as part of an investigational case series of patients with unilateral LSCD treated with ex vivo cultured autologous limbal stem cell transplantation.

Methods: Twenty subjects were treated with transplanted ex vivo cultured limbal epithelial stem cells that were grown on 3x3cm sheets of human amniotic membrane, from a 1.5x1.5mm limbal biopsy taken from the unaffected eye, using an animal product-free culture system as previously published (Kolli et al., Stem Cells. 2010). Questionnaires, including the Ocular Surface Disease Index (OSDI) and the National Eye Institute Visual Function Questionnaire 25 (NEI-VFQ) were completed at baseline, 3, 6 and 12 months postoperatively. The NEI-VFQ data was re-calculated into two continuous scales, the Long Form Socio-emotional Scale (LFSES₂₅) and the Long Form Visual Functioning Scale (LFVFS₂₅), scoring systems developed by Rasch analysis to enhance the NEI-VFQ (Pesudovs et al., J Cataract Refract Surg. 2010). Interim data is presented for 12 patients who have completed 12 month follow-up.

Results: The baseline NEI-VFQ scores were significantly higher than published normal subjects for both ocular pain (p=.047) and mental health subsections (p=.021); other subsection scores were not significantly different. OSDI scores were qualitatively improved at all time-points after treatment compared to baseline, although not statistically significant (p=.325).Following therapy, scores for most NEI-VFQ subsections improved slightly. There were no significant differences between baseline and post treatment time points for the LFVFS₂₅ (p=.951) and LFSES₂₅ (p=.833).

Conclusions: There is the lack of suitable tools for assessing patient outcomes in LSCD. As commonly used measures, the NEI‑VFQ and OSDI scores were included in the study protocol although they have known limitations. The LFVFS₂₅ and LFSES₂₅ were used to generate more valid, statistically meaningful measures. The data presented doesn’t show a significant improvement in patient reported outcomes; data collection continues. It is important to assess patient outcomes, as well as clinical measures, when considering complex diseases and interventions.