Background/aims The Mycotic Ulcer Treatment Trial I (MUTT I) was a double-masked, multicentre, randomised controlled trial, which found that topical natamycin is superior to voriconazole for the treatment of filamentous fungal corneal ulcers. In this study, we determine risk factors for low vision-related quality of life in patients with fungal keratitis.

Methods The Indian visual function questionnaire (IND-VFQ) was administered to MUTT I study participants at 3 months. Associations between patient and ulcer characteristics and IND-VFQ subscale score were assessed using generalised estimating equations.

Results 323 patients were enrolled in the trial, and 292 (90.4%) completed the IND-VFQ at 3 months. Out of a total possible score of 100, the average VFQ score for all participants was 81.3 (range 0–100, SD 23.6). After correcting for treatment arm, each logMAR line of worse baseline visual acuity in the affected eye resulted in an average 1.2 points decrease on VFQ at 3 months (95% CI −1.8 to 0.6, p<0.001). Those who required therapeutic penetrating keratoplasty had an average of 25.2 points decrease on VFQ after correcting for treatment arm (95% CI −31.8 to −18.5, p<0.001). Study participants who were unemployed had on average 28.5 points decrease on VFQ (95% CI −46.9 to −10.2, p=0.002) after correcting for treatment arm.

Conclusions Monocular vision loss from corneal opacity due to fungal keratitis reduced vision-related quality of life. Given the relatively high worldwide burden of corneal opacity, improving treatment outcomes of corneal infections should be a public health priority.

Trial registration number Clinicaltrials.gov Identifier: NCT00996736.