title: Changes in metamorphopsia in daily life after successful epiretinal membrane surgery and correlation with M-CHARTS score.
abstract: OBJECTIVE
  To determine the correlation between the changes in metamorphopsia in daily life environment and the M-CHARTS scores after epiretinal membrane (ERM) removal, and to determine the criterion for determining whether clinically significant changes in the metamorphopsia score have occurred in M-CHARTS.
  
  
  METHODS
  We studied 65 eyes undergoing vitrectomy for unilateral ERM. Self-administered questionnaires were used to examine the metamorphopsia in their daily life. The degree of metamorphopsia was determined by M-CHARTS. The receiver operating characteristic curve was used to determine the best predictor of the changes in metamorphopsia in daily life. To determine the reproducibility of the M-CHARTS score, another set of 56 eyes with ERM was tested twice on two different days.
  
  
  RESULTS
  The postoperative changes in the logarithm of the M-CHARTS score was defined as M2-value. The area under the receiver operating characteristic curve for the M2-value as a predictor of the changes in metamorphopsia in daily life was larger than area under the receiver operating characteristic curve obtained for any other parameter. The optimal cutoff value was -0.4. The 95% limits of agreement between test and retest measurements had a reproducibility of ±0.3 logarithm of the M-CHARTS score. Taking into account not only the reproducibility but also the consistency with the subjective changes, we determined the criterion for clinically significant changes in the M-CHARTS scores as a change of the M2-value by ≥0.4.
  
  
  CONCLUSIONS
  Evaluating the changes in the M-CHARTS scores in logarithmic form is favorable not only theoretically but also from the perspective of consistency with the subjective changes.
authors: Department of Ophthalmology, Sapporo City General Hospital, Sapporo, Japan ; Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
authors: Takamasa
authors: T
authors: Kinoshita
authors: Department of Ophthalmology, Sapporo City General Hospital, Sapporo, Japan.
authors: Hiroko
authors: H
authors: Imaizumi
authors: Department of Ophthalmology, Sapporo City General Hospital, Sapporo, Japan.
authors: Hirotomo
authors: H
authors: Miyamoto
authors: Department of Ophthalmology, Sapporo City General Hospital, Sapporo, Japan.
authors: Utako
authors: U
authors: Okushiba
authors: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
authors: Yuki
authors: Y
authors: Hayashi
authors: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
authors: Takashi
authors: T
authors: Katome
authors: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, Japan.
authors: Yoshinori
authors: Y
authors: Mitamura
keywords: ERM; criterion; metamorphopsia score; vitrectomy