Abstract
Purpose :
Keratoprosthesis (Kpro) represents an advance in the treatment of patients with ocular surface disorders and corneal opacities. When low vision persists, functional visual loss may be minimized by magnification with optical devices. This study aimed to assess self-reported visual function and related quality of life in low vision patients with Boston type I Kpro referred to visual rehabilitation.
Methods :
Adult subjects with best-corrected distance visual acuity from 0.6 to 1.5logMAR in the better-vision eye and referred to visual rehabilitation were included. Participants underwent monocular and binocular visual acuity (ETDRS chart) for distance (DVA) and near (NVA) measurements, optical device training and visual performance evaluation with the magnification. The WHO 25-item International Visual Functioning Questionnaire (VFQ) was applied in individual interviews before and after low vision rehabilitation. VFQ scores were calculated for the domains of visual functioning (VF: subdomains general vision, distant vision, near vision, sensory adaptation), quality of life (QL: subdomains pain, social activities, mental status) and vision related quality of life (VQL: VF and QL). Internal consistency of responses was measured by Cronbach’s alpha statistic.
Results :
Six participants (5 males – 83%) aged 25 to 67 years (mean=48.5±13.7) were included. Mean binocular DVA was 0.92±0.13logMAR and NVA 0.86±0.11logMAR. All patients were enabled to use optical devices which were prescribed for distance (telescopes; 2.5x to 4.0x) in 83% and for near (spherical spectacle and hand-held magnifiers; 1.5x to 2.5x) in 50% of them, improving visual performance on average in 6 lines (logMAR chart). Before low vision rehabilitation, mean VF, QL and VQL scores were 58.0±17.2, 73.8±11.7 and 63.5±14.1, increasing 12.5, 4.8 and 9.8 points, respectively, after optical devices adaptation. There was a strong association between the subdomain distance vision score and the distance visual performance with optical magnification (r=0.73) as well as for near vision (r=0.99). Internal consistency of responses for VQL was 0.91 before and 0.80 after magnifiers usage.
Conclusions :
Low vision rehabilitation enhanced the visual performance of this small group of patients, impacting positively on their quality of life. Optical devices should be considered as an alternative in the treatment of patients with Kpro and low vision.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.