Scleral lenses have emerged as an efficacious treatment option for various types of intractable ocular surface diseases with many advantageous results. The purpose of this study was to report the efficacy and safety of the LK scleral lenses and determine their suitability in Asian patients with intractable ocular surface diseases. Subjects with intractable ocular surface diseases are enrolled to fit LK scleral lenses for 12 weeks for a prospective study. Evaluations are performed at 1, 4, 8 and 12 weeks. General patient demographics and medical history, visual acuities, thorough ophthalmic evaluation, ocular surface disease index and National Eye Institute 25-Item Visual Function Questionnaire are collected for each patient.

To date, there are several commercially manufactured scleral lenses of different designs and sizes, all of which have been proven to be clinically beneficial in a wide spectrum of diseases. Especially in the management of intractable ocular surface diseases, scleral lenses with large diameters are commonly used so that the lens entirely rests on the sclera with sufficient tear reservoir. PROSE devices (Boston Foundation for Sight, Needham, MA), one of the first and representative scleral lenses shown to have long-term clinical benefits for complex corneal diseases, have large diameters of 17.5 to 23.0 mm. However, in Republic of Korea, only scleral lenses with small diameters are currently available. SoClearⓇ and OnefitⓇ scleral lenses, two of the most commonly used scleral lenses in Republic of Korea, possess diameters ranging from 14.1 to 15.5 mm and 13.3 to 15.0 mm, respectively, and are not actually fully scleral but more of a corneoscleral type lenses. Furthermore, Asians have smaller palpebral fissures with tighter eyelids than the Western population, which may restrict patients' tolerability of wearing a large scleral lens and limit its clinical benefits. Therefore, a more suitable scleral lens for Asians with larger diameter is required.

Accordingly, this study investigates the efficacy and safety of the LK scleral lens (Lucid Korea LTD, Seoul, Republic of Korea), which has been newly manufactured to have larger diameters than currently available commercial lenses, and determines their suitability in Asian patients with intractable ocular surface diseases.

Inclusion Criteria:

• Age between 20 to 69 years
• Intractable ocular surface disease
• Uncorrected visual acuity better than count finger and ≥ 0.3 logMAR (log of the Minimum Angle of Resolution)
• Best-corrected visual acuity ≥ 0.3 logMAR (log of the Minimum Angle of Resolution)

Exclusion Criteria:

• Currently under treatment for infectious keratitis
• Difficulty of scleral lens application due to severe allergic conjunctivitis, low compliance, and other potential contraindications
• Diabetes mellitus and/or hypertension
• Pregnant or planning pregnancy E. Unwilling to follow study schedule F. Enrolled in another clinical study G. Determined inappropriate under investigators' discretion