A Prospective Questionnaire-Based Study To Assess The Risk Factors Of Midday Fogging Among Scleral Lens Users

To identify risk factors for midday fogging (MDF) among scleral contact lens (SCL) users with various corneal disease.

Patients with any corneal pathology, who were seen in cornea clinic between January 2022 and December 2022, and were referred to contact lens clinic for scleral lenses fitting were included. Details of all patients were taken from the electronic medical record and they were subjected to the questionnaire telephonically. The questionnaire consisted of nineteen questions.

After an informed consent, patients were subjected to the questionnaire telephonically in their preferred language. Questions were designed to assess factors including underlying corneal pathology, age of the scleral lens in use, lens material, diameter; average duration of lens wear, type of solution for cleaning and storage of the lens; fluid used as reservoir to fill the vault; type of lubricating eyedrops and other non-lubricating topical medications, mode of lens storage(dry vs wet), use of topical steroids, and presence or absence of MDF.

A total of 465 eyes were included. Of the total, 55.3% had ectatic disorders, keratoconus being the most common etiology. Forty percent had ocular surface disorders(OSDs), of which Stevens-Johnson syndrome was the commest. Of these, 66.5%(309 eyes) reported MDF. Among the patients with no MDF,73% eyes had ectatic disorders. While in MDF group, there was no significant difference among ectatic disorders and OSDs. When compared, patients who were on topical immunomodulators(p=0.005) and topical steroids(p=0.0002) had significantly increased MDF. No significant difference between two groups in terms of different lens cleaning(p=0.25) and/ or storage solutions(p=0.18). Also, No significant difference in MDF among dry or wet lens storage(p=0.06)

Midday fogging is a major concern among patients with SCL users. Use of topical steroids and immunomodulators may contribute to the occurrence of MDF. This can be indirectly due to increased ocular surface inflammation in such eyes which demands use of these medications. Etiology, type of lens material, different type of cleaning or storage solution, or storage modality (dry vs wet storage) may not play a significant role in MDF.