3D-Printed Contact Lenses to Release Polyvinyl Alcohol as a Therapeutic Agent for the Treatment of Dry Eyes

Abstract

Purpose: Dry eye disease is highly prevalent, and the most common treatment, lubricating eye drops, only remains effective for a very short period of time. This project aims to 3D print a proof-of-concept, custom-fit, polyvinyl alcohol (PVA)-eluting contact lens (CL) for the treatment of dry eye disease. PVA is a commonly used viscosity enhancer in eye drops, with the capability of reducing symptoms of dry eye by stabilizing the tear film and reducing tear evaporation. The protective effects of PVA could be attributed to its water-retaining ability, which provides moisturization and prevents the loss of water. Method: In this work, a low-cost stereolithography-based 3D printer was retrofitted with a humidity and temperature control kit to 3D print a PVA-loaded custom-fit CL. To evaluate the print quality of the 3D-printed CL, circularity was used to evaluate the shape fidelity in 3D printing. The PVA release from these lenses was assessed, along with its role in acting as a viscosity enhancer. The effect of PVA was further analyzed by a dry eye disease (desiccation stress) cell model. Results: The shape fidelity evaluation of the 3D-printed CL displayed excellent circularity. The diameter, sagittal depth, and base curve of the 3D-printed lenses were measured to be 14.27 ± 0.06 mm, 3.77 ± 0.16 mm, and 6.4 ± 0.24 mm, respectively. The PVA release curves showed that approximately 1300 µg of PVA was released over the study duration of 24 h. Conclusions: Overall, this work demonstrates that a 3D-printed PVA-eluting CL is a promising candidate for the treatment of dry eye.

Keywords: desiccation stress; dry eye disease; polyvinyl alcohol; shape fidelity; three-dimensional-printed contact lenses.

Scheme 1

Scheme of preparation of P-Gel prepolymer solution and 3D printing of CL.

Figure 1

Comparative optical clarity of (a) commercially available Dailies Aqua Comfort Plus™ CL and (b,c) 3D-printed PVA-loaded CLs (P-Gel-1.5% and P-Gel-3%). The images were taken on a 3D-printed eye model mimicking the human eye to show the fitting of these lenses and their optical clarity.

Figure 2

Three-dimensional printed contact lenses (a) before and (b) after washing and post-curing.

Figure 3

Analysis of shape fidelity and circularity of 3D-printed contact lenses (calculations based on 2D top view).

Figure 4

(a) Optical transparency of 3D-printed CLs on a colored background. (b) Optical transmittance curves of Dailies Aqua Comfort Plus™ (Nelfilcon A), GelMA, P-Gel-1.5%, and P-Gel-3%.

Figure 5

(a) Cumulative PVA release curves of P-Gel-1.5% and P-Gel-3%. (b) Instantaneous release of PVA (µg/mL) from P-Gel-1.5% and P-Gel-3%. (c) Modeling of the PVA release data using the Korsmeyer–Peppas model (R² = 0.9806 and R² = 0.9864 for P-Gel-1.5% and P-Gel-3%, respectively).

Figure 6

Graph representing viscosity as a function of PVA concentration.

Figure 7

Effect of PVA and Refresh Classic eye drops on HCECs and resistance against desiccation stress (* p < 0.05 and ** p < 0.005).