Autologous serum eye drops diluted with 0.5% methylcellulose and 0.9% saline solution: a clinical comparative study.

Purpose: This clinical study compared autologous serum eye drops diluted with 0.5% methylcellulose and 0.9% saline solution. The subjective criteria for symptom improvement and the objective clinical criteria for response to therapy were evaluated.

Methods: This longitudinal prospective study enrolled 23 patients (42 eyes) with persistent epithelial defects or severe dry eye disease refractory to conventional therapy who had been using autologous serum 20% prepared with methylcellulose for > 6 months and started on autologous serum diluted in 0.9% saline solution. The control and intervention groups consisted of the same patients under alternate treatments. The subjective criteria for symptom relief were evaluated using the Salisbury Eye Evaluation Questionnaire. The objective clinical criteria were evaluated through a slit-lamp examination of the ocular surface, tear breakup time, corneal fluorescein staining, Schirmer's test, rose Bengal test, and tear meniscus height. These criteria were evaluated before the diluent was changed and after 30, 90, and 180 days.

Results: In total, 42 eyes were analyzed before and after 6 months using autologous serum diluted with 0.9% saline. No significant differences were found in the subjective criteria, tear breakup time, tear meniscus, corneal fluorescein staining, or rose Bengal test. Schirmer's test scores significantly worsened at 30 and 90 days (p=0.008). No complications or adverse effects were observed.

Conclusions: This study reinforces the use of autologous serum 20% as a successful treatment for severe dry eye disease resistant to conventional therapy. Autologous serum in 0.9% saline was not inferior to the methylcellulose formulation and is much more cost-effective.