The mean VFQ-25 composite score was 76.5 ± 11.1 points (range 43.9 to 95.5) for patients with naïve BRVO at baseline in this study. Previous studies have reported that the mean VFQ-25 composite scores at baseline for patients with ERM, MH, DME, and PDR were 66.2, 70.5, 63.1, and 56.3, respectively7–9, 11. Thus, the mean VFQ-25 composite score in BRVO was found to be relatively higher than in other retinal disorders.
Treatment of BRVO with IVR improved the VFQ-25 composite score and all subscale scores except for “general health.” An improvement from baseline in the mean VFQ-25 composite score was observed as early as 12 months, which accounted for 9.9 points in this study. Previous studies have reported that the mean change from baseline VFQ-25 composite score in patients with BRVO was 9.3 points and 10.4 points in the 0.3 mg and 0.5 mg ranibizumab treatment groups, respectively, in the BRAVO study13, while it was 9.4 points with aflibercept treatment in the VIBRANT study16. While our results were equally effective in determining the VR-QOL, there was a difference in regimens between our study and these two studies. The treatment period was day 0 to month 2 in this study, while it was day 0 to month 5 in the BRAVO study13 and day 0 to month 6 in the VIBRANT study16. Therefore, from the viewpoint of VR-QOL, IVR treatment with 3 + PRN may be adequate to treat patients with naïve BRVO.
The mean VFQ-25 composite score at baseline in BRVO was worse than that in the healthy subjects in this study. Okamoto et al.7,11 reported that the preoperative VFQ-25 composite scores were significantly lower in patients with ERM and PDR than in healthy subjects. Patients with BRVO after treatment had a good mean VFQ-25 composite score, similar to healthy subjects. A previous study had revealed that the VFQ-25 composite score remained significantly lower for the patients with ERM, MH, DME, RD, and PDR than the healthy subjects, even after surgery18. Therefore, unlike other retinal diseases, the treatment of BRVO with IVR can be considered to be favorable in terms of QOL prognosis.
As shown in the results, IVR treatment significantly improved almost all VFQ-25 subscale scores for patients with BRVO, similar to those in healthy subjects. However, only subscales “near vision” and “mental health” did not improve to normal level, even after treatment. Although the score of “near vision” of patients with inferior BRVO was the same as that of healthy subjects, that of patients with superior BRVO was lower than that of healthy subjects. Patients with superior BRVO had inferior visual field impairments. It is well known that humans use an inferior visual field for near work, such as reading books and detailed work19,20. Therefore, QOL for patients with superior BRVO with inferior visual field impairment may have been lower than that of healthy subjects.
In this study, there was no significant association between the VFQ-25 composite score and the BCVA of patients with BRVO before and after treatment. Frick et al.21 reported that VR-QOL score correlated positively with BCVA in patients with uveitis. Matza et al.22 revealed that changes in BCVA were associated with corresponding changes in VR-QOL among patients with diabetic retinopathy. Previous studies have revealed that contrast sensitivity affected VR-QOL of patients with DME and RD9,10. In addition, it is known that metamorphopsia is significantly associated with VR-QOL in ERM and MH7,8. Based on the results of these reports, visual functions such as metamorphopsia and contrast sensitivity might be associated with the VR-QOL in patients with BRVO; further studies are required to identify the visual function associated with VR-QOL.
One of the limitations of our study was the small sample size, which reduced the probability of identifying statistically significant associations. The placebo effect with the VFQ-25 can be a limitation of this study. The patients recognized that they had received IVR treatment and may have answered VFQ-25 questions more positively because of the expectation that they would benefit from the treatment. This could not be avoided by the study design and could have accounted for some of the improvements in the VFQ-25.
In summary, the VR-QOL was compromised in patients with naïve BRVO. Treatment with IVR improved the VFQ-25 composite score and subscales, except for “general health,” to normal levels. Visual acuity was not associated with the VR-QOL in patients with BRVO.