The VFQ-25 composite score improved from 62.6 points before treatment to 74.3 points 12 months after treatment in this study. The VFQ-25 composite score in CRVO at baseline was 66.9 points in a study by Deramo et al.22 and 77.4 points in the COPERNICUS study,23 and the scores observed in our study were lower than those of the COPERNICUS study. Eligible patients had BCVA of 20/40 to 20/320 in the COPERNICUS study,23 whereas there was no criterion for BCVA of eligible patients in the present study, consequently, the range of BCVA was from 20/20 to 20/2000. In the present study, the VFQ-25 composite score at baseline may have been lower than that in the COPERNICUS study because our study included patients with extremely poor vision.
The mean increase from baseline VFQ-25 composite score was 9.5 points after 6 months, and 11.7 points after 12 months of treatment in this study. The mean increase from the baseline VFQ-25 composite score was 7.1, 7.2, and 7.1 points in the GALILEO,4 COPERNICUS,23 and CRUISE3 studies, respectively, after 6 months and 7.8, 7.5, and 7.1 points respectively, after 12 months of treatment. In our study, the mean number of injections for 12 months was 5.6, which was lower than the 9.8 in the CRUISE study,3 and 11.8 in the GALILEO study.4 Despite these results, there was a greater improvement in the VFQ-25 composite score in the present study than in other studies, suggesting that pro re nata (3 + PRN) is acceptable as a standard treatment for CRVO in terms of QOL.
The VR-QOL has been investigated in patients with various retinal diseases, including ERM,12,13 MH,14 RD,15–17 PDR,18,19 DME,19 and BRVO.20,21 The mean increase from baseline VFQ-25 composite score was 11.7 points in ERM,13 6.9 points in MH,14 10.8 points in PDR,19 6.0 points in DME,19 and 9.0–9.4 points in BRVO.21,24 Despite differences in the observation period and inclusion criteria, the improvement in the VFQ-25 composite score of patients with CRVO was nearly similar to that of patients with other retinal diseases after treatment, suggesting that anti-VEGF treatment in patients with CRVO has clinical significance.
The IVR treatment for CRVO improved BCVA and CFT immediately after treatment and was maintained throughout the following 12 months. In the present study, the improvement in BCVA at 12 months was 0.2 logarithm of the minimum angle of resolution (logMAR) (10 letters). In the CRUISE3 and GALILEO study,4 BCVA at 12 months after anti-VEGF treatment was 13.9 and 16.9 letters from baseline, respectively. The reason for the less extent of improvement in BCVA in our study compared with that in other studies may be the inclusion criteria. As mentioned earlier, patients with CRVO in the CRUISE and GALILEO studies had a BCVA of 20/40 to 20/320,3,4 whereas, in the present study, the range of BCVA of the patients at baseline was 20/20 to 20/2000. The improvement in BCVA was lower than that in the abovementioned studies because our study included patients with extremely poor vision and patients with good vision.
We observed that the baseline VFQ-25 composite score was not associated with BCVA, whereas the post-treatment composite score showed a significant correlation with post-treatment BCVA. Consistently, Deramo VA et al. also reported that the VR-QOL of pre-treatment patients with CRVO was not associated with visual acuity.22 Visual acuity and VR-QOL are related in common eye diseases25; however, the relationship between VR-QOL and visual functions (except visual acuity) has been indicated in many retinal diseases. The VR-QOL in ERM17,23 and MH21 was associated with metamorphopsia and not visual acuity. In PDR,22,23 DME,23 after RD,18 and vitreous floaters,26 contrast sensitivity affected the VR-QOL. Moreover, stereopsis was associated with VR-QOL after RD surgery.20 Visual dysfunctions such as metamorphopsia27 and aniseikonia28 have been reported in patients with CRVO; hence, visual function factors other than visual acuity may be involved in the deterioration of VR-QOL.
In the present study, IVR treatment for patients with CRVO significantly improved subscale items of general vision, ocular pain, near activities, distance activities, mental health, role difficulties, and dependency. At baseline, all subscale items were lower in patients with CRVO than in normal controls. Even after treatment, subscale items, including general health, general vision, near activities, social functioning, mental health, role difficulties, dependency, and peripheral vision in CRVO, were significantly lower than those in the normal controls. In addition, the VFQ-25 composite score and subscale items social functioning, and dependency after treatment showed a significant correlation with BCVA. Most subscale items in pre-treatment in patients with CRVO were lower than those in normal controls, consistent with the findings of previous reports.22 Although anti-VEGF treatment for CRVO improved the values of many subscale items, those related to the quality of vision (general vision, near activities, and peripheral vision) and psychosocial functioning (social functioning, mental health, role difficulties, and dependency) were more impaired than those in normal controls even after treatment. Further treatment aimed at improving visual function, as well as social and psychological care by medical social workers, are necessary.
The limitations of this study were a small sample size and short follow-up duration. We evaluated the patients for 12 months after treatment. In the COPERNICUS study, BCVA in patients with CRVO treated with intravitreal aflibercept injection at 24 months was 3.2 letters less than that at 12 months.29 As CRVO is a retinal disease with a poor prognosis, it is important to monitor visual functions and QOL in the long term. Future studies with a larger sample size and longer follow-up duration will further improve our understanding of VR-QOL in patients with CRVO.