In our present study, we used the Turkish-translated NEI VFQ-25 questionnaire, which was developed to accurately characterize visual function with the self-reported dimensions. The reliability of the NEI VFQ-25 questionnaire was evaluated and was found to accurately measure VR-QOL. The NEI-VFQ 25 questionnaire was found to be able to discriminate between the ERM group and the CG. Missing data in the driving category may be due to populaton based differences (rate of having driving license or driving).
A successful ERM surgery results in mostly positive visual results.[9, 10] In our patients, increasing levels of visual acuity are also observed in their 6-month follow-up. Visual acuity may be poor in expressing many aspects of visual function and may be insufficient to predict whether individuals have difficulties in real-world activities. Our results confirm this information and visual acuity explained 19% of the composite score of NEI VFQ-25. However, metamorphopsia after ERM surgery may persist[7, 12] and impair vision-related quality of life. In our results, the composite score of patients with ERM remained lower than the CG, 6 months after a successful surgery. This situation is similar to previous studies of NEI-VFQ 25 assessment after ERM surgery.
Binocular interference was defined as a situation in which the visual quality with both eyes open is worse than with only 1 eye, associated with the patient closing 1 eye. It was reported in a recent study that binocular interference worsens the quality of life of patients with ERM. ERM is usually unilateral or asymmetrically bilateral. The visual performance of the patients' fellow eyes was generally unaffected. Therefore, although the composite score of patients with unilateral ERM is lower than the CG, it is found that patients with ERM are similar to the CG in other categories, except for the categories of general vision, ocular pain and near and distance activities, as seen in the subscale. Although the visual acuity of patients with ERM has improved, it is seen that it does not reach a sufficient level compared to CG. Postoperative unequal vision levels may cause binocular interference and result in lower subscale categories compared to the CG. However, the thing to consider when evaluating these results is that we performed NEI-VFQ 25 questionare at postoperative 6th month. After ERM surgery, visual improvement has been reported in 43% of eyes at 12 month, 54% at 2 year, and 60% at 3 year, and this may lead to an improvement in NEI-VFQ 25 results in the long term.
In previous studies evaluating the postoperative NEI VFQ-25 results of ERM patients, mean NEI VFQ-25 composite score are as follows, respectively; 77.9, 78.5. The mean composite scores of NEI VFQ-25 after vitreoretinal surgery in patients with macular hole, rhegmatogenous retinal detachment, proliferative diabetic retinopathy and age-related macular degeration have been reported as 82.4, 80.3, 68.5 and 54.4 respectively. In the present study, the mean composite score of NEI VFQ-25 was 71.9 and it was lower than the ERM patients reported in the literature and was similar to the score of proliferative diabetic retinopathy (PDR) patients. It should be noted that the composite score was better in diseases that usually affect only one side, such as ERM, macular hole and rhegmatogenous retinal detachment, than in diseases that usually affect both sides, such as PDR and age-related macular degeneration.
Ghazi-Nouri et al. reported a significant association between binocular BCVA and VR-QOL, but no association with VR-QOL for monocular BCVA, metamorphopsia, and contrast sensitivity in ERM patients. Metamorphopsia in age-related macular degeneration and vitreomacular traction has been reported to be associated with VR-QOL. Another study reported that stereopsis was consistently altered in patients with ERM and was associated with VR-QOL.
The limitation of our study is that we did not evaluate the preoperative NEI VFQ-25 score and did not evaluate the metamorphopsia and steropsis of the patients.
In conclusion, according to the reviewed literature, findings such as metamorphopsia and impaired stereopsis may persist in the postoperative period and may impair VR-QOL in patients with ERM. Diseases with binocular involvement affected VR-QOL more. In present study, we demonstrated that near and distance activity scores and ocular pain scores were worse in ERM patients with low visual acuity. We demonstrated that the NEI VFQ-25 questionnaire can discriminate ERM patients from healthy individuals and that visual acuity does not exactly reflect VR-QOL. To our knowledge, this is the first paper reporting NEI VFQ-25 after ERM surgery in Turkish population. More comprehensive studies are needed to evaluate the performance of the NEI VFQ-25 questionnaire to discriminate between other macular diseases.