Is metamorphopsia more important than visual acuity in vitreomacular interface disorders? A scoping review

Background Vitreomacular interface disorders are known to reduce vision-related quality of life (VR-QoL). This is due to both reduced visual acuity and metamorphopsia. In clinical practice, visual acuity is measured routinely, but quantitative measurements of metamorphopsia are less frequent. We conducted a scoping literature review to determine whether metamorphopsia or visual acuity has the greatest effect on VR-QoL. Methods A literature review, of studies published in English, and indexed in Medline or Embase, in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. 65 studies were identified. 55 were excluded as they did not meet the inclusion criteria. Results Of the 10 publications, six studied epiretinal membrane, two studied full-thickness macular hole, one studied vitreomacular traction with or without macular hole and one included both macular hole and epiretinal membrane. A variety of different methods were used to measure metamorphopsia and VR-QoL. Of the eight studies reporting the association between preoperative metamorphopsia and VR-QoL, five found a significant correlation. Six studies examined the association between post-operative metamorphopsia and VR-QoL, five of which found a significant correlation. Five studies looked for any link between reduction in metamorphopsia and improvement in VR-QoL. All five found a significant association. In contrast, only two of eight studies found any association between preoperative vision and VR-QoL, and none found any relationship between improvement in visual acuity and improvement in VR-QoL. Conclusions Although the published evidence is limited, it appears that metamorphopsia may be a better predictor of preoperative and postoperative VR-QoL than visual acuity. Further research is necessary to confirm this, but metamorphopsia should be measured when assessing vitreomacular interface disorders.