Relationship between Recurrence of Macular Edema Due to Branch Retinal Vein Occlusion and Changes in Choroidal Thickness

Relationship between retinal volume changes and the prognosis of BRVO-ME treated with ranibizumab

Background

This study aimed to evaluate the efficacy of ranibizumab for the treatment of macular edema secondary to branch retinal vein occlusion (BRVO-ME), changes in retinal volume and central retinal thickness (CRT) before and after therapy, and the connection between visual prognosis and changes in retinal volume.

Methods

The 120 patients(121 eyes) of BRVO-ME were recruited from July 2020 to October 2022 at the Affiliated Hospital of Weifang Medical University. The clinical data of patients were retrospectively examined for changes in best-corrected visual acuity (BCVA), retinal volume, and CRT at 1 day, 1 week, 1 month, 3 months, 6 months and 1year after treatment.

Findings

Visual acuity improved gradually and became steady approximately 1 months after treatment, whereas retinal volume decreased gradually in both the outer and full layers and stabilized around 6 month after treatment. The decline in retinal volume and CRT was more visible in the deeper layers than in the inner levels. A higher correlation was observed between retinal volume and BCVA than between CRT and BCVA. BCVA after one year of treatment had a high correlation with baseline outer retinal volume.

Interpretation

Treatment of BRVO-ME with ranibizumab is highly effective, and the recovery of visual function was depends more on early treatment. The outer retina is the major site of edema. Changes in retinal volume may serve as a better predictor of visual prognosis than changes in CRT. Baseline ourter retinal volume is correlated with long-term visual prognosis.

The measurement and correlation analysis of scleral and choroid thickness in branch retinal vein occlusion

To use Optical Coherence Tomography (OCT) to measure scleral thickness (ST) and subfoveal choroid thickness (SFCT) in patients with Branch Retinal Vein Occlusion (BRVO) and to conduct a correlation analysis. A cross-sectional study was conducted. From May 2022 to December 2022, a total of 34 cases (68 eyes) of untreated unilateral Branch Retinal Vein Occlusion (BRVO) patients were recruited at the Affiliated Eye Hospital of Nanchang University. Among these cases, 31 were temporal branch vein occlusions, 2 were nasal branch occlusions, and 1 was a superior branch occlusion. Additionally, 39 cases (39 eyes) of gender- and age-matched control eyes were included in the study. Anterior Segment Optical Coherence Tomography (AS-OCT) was used to measure ST at 6 mm superior, inferior, nasal, and temporal to the limbus, while Enhanced Depth Imaging Optical Coherence Tomography (EDI-OCT) was used to measure SFCT. The differences in ST and SFCT between the affected eye, contralateral eye, and control eye of BRVO patients were compared and analyzed for correlation. The axial lengths of the BRVO-affected eye, contralateral eye, and control group were (22.92 ± 0.30) mm, (22.89 ± 0.32) mm and (22.90 ± 0.28) mm respectively, with no significant difference in axial length between the affected eye and contralateral eye (P > 0.05). The SFCT and ST measurements in different areas showed significant differences between the BRVO-affected eye, contralateral eye in BRVO patients (P < 0.05). The CRT of BRVO-affected eyes was significantly higher than that of the contralateral eyes and the control eyes (P < 0.001). In comparison between BRVO-affected eyes and control eyes, there were no statistically significant differences in age and axial length between the two groups (P > 0.05). However, significant differences were observed in SFCT and temporal, nasal, superior, and inferior ST between the two groups (P < 0.05). The difference in temporal ST between the contralateral eyes and the control eyes was not statistically significant (t = - 0.35, P = 0.73). However, the contralateral group showed statistically significant increases in SFCT, nasal, superior and inferior ST compared to control eyes (t = - 3.153, 3.27, 4.21, 4.79, P = 0.002, 0.002, < 0.001, < 0.001). However, the difference between the CRT of the contralateral and control eyes was not statistically significant (P = 0.421). When comparing SFCT and ST between BRVO-affected eyes with and without macular edema, no statistically significant differences were found (t = - 1.10, 0.45, - 1.30, - 0.30, 1.00; P = 0.28, 0.66, 0.21, 0.77, 0.33). The thickness of SFCT and temporal ST in major BRVO group is higher than the macular BRVO group and the difference was statistically significant (t = 6.39, 7.17, P < 0.001 for all). Pearson correlation analysis revealed that in BRVO patients, there was a significant positive correlation between SFCT/CRT and temporal ST (r = 0.288, 0.355, P = 0.049, 0.04). However, there was no correlation between SFCT/CRT and nasal ST, superior ST, and inferior ST (P > 0.05). In BRVO patients, both SFCT/CRT and ST increase, and there is a significant correlation between SFCT/CRT and the ST at the site of vascular occlusion.

Anti-Vascular Endothelial Growth Factor Therapy with or Without Initial Steroid Therapy for Macular Edema in Branch Retinal Vein Occlusion

Purpose

In branch retinal vein occlusion (BRVO), administering steroid injections to inhibit expression of inflammatory factors in the first phase of macular edema may reduce recurrence of the edema. The purpose of our study was to investigate the functional and morphological prognosis and frequency of recurrence after injection of an anti-vascular endothelial growth factor (VEGF) with and without initial steroid therapy to treat macular edema with BRVO.

Patients and Methods

Patients with BRVO and macular edema (41 eyes) received intravitreal ranibizumab injection (IRI) alone (IRI group, 21 eyes) or subtenon triamcinolone (STTA) injection and IRI (combination group, 20 eyes). Patients in both groups with recurrent macular edema received further IRI as appropriate. A laser flare meter was used to assess aqueous flare values, and an optical coherence tomography device was used to measure central macular thickness (CMT). Before the first treatment, we obtained samples of aqueous humor and analyzed them by the suspension array method to evaluate VEGF, placental growth factor (PlGF), platelet-derived growth factor (PDGF)-AA, soluble intercellular adhesion molecule (sICAM)-1, monocyte chemoattractant protein 1 (MCP-1), interleukin (IL)-6, IL-8, and interferon-inducible 10-kDa protein (IP-10).

Results

The two groups were not significantly different with regard to levels of VEGF, PlGF, PDGF-AA, sICAM-1, MCP-1, IL-6, IL-8, or IP-10. Best-corrected visual acuity, CMT, and aqueous flare value (IRI group, baseline 8.69 ± 4.55 photon counts/ms; combination group, baseline 9.21 ± 3.72 photon counts/ms) improved significantly in both groups without significant intergroup differences. Analyses showed no significant intergroup differences in the mean number of IRIs during the 12-month follow-up, but the proportion of patients without recurrence (ie, who received only one IRI) was significantly higher in the combination group than in the IRI group (P = 0.032). Furthermore, the time to initial recurrence was significantly longer in the combination group than in the IRI group (P = 0.003).

Conclusion

These findings suggest that initial STTA injection and IRI may have a synergistic effect in patients with BRVO and macular edema in that they increase the time between anti-VEGF treatments.

Effects of intravitreal injection of ranibizumab and aflibercept for branch retinal vein occlusion on the choroid: a retrospective study

BACKGROUND

Macular edema is found in more than half of branch retinal vein occlusion (BRVO) cases, leading to visual loss in most of these cases. Intravitreal injection of anti-vascular endothelial growth factor is currently the standard treatment for macular edema due to BRVO (BRVO-ME). The difference in the effects of aflibercept and ranibizumab on the choroid in BRVO-ME is unknown. Therefore, we analyzed the effects of intravitreal injection of ranibizumab and aflibercept on BRVO-ME.

METHODS

We retrospectively observed changes in choroidal thickness in the subfoveal region in 36 patients with BRVO-ME who visited the Department of Ophthalmology at the Juntendo University Urayasu Hospital. The patients were treated with intravitreal injection of aflibercept or ranibizumab and followed up for 12 months or more.

RESULTS

The observed point bifurcated into the affected and non-affected sides 500 μm from the fovea. The central macular thickness (CMT) and subfoveal choroidal thickness (SFCT) were 564.2 ± 268.5 μm and 228.8 ± 50.1 μm, respectively, in the ranibizumab group (16 patients, 16 eyes) and 542.4 ± 172.5 μm and 246.1 ± 59.1 μm, respectively, in the aflibercept group (20 patients, 20 eyes). The changes in CMT at 12 months were 324.0 ± 262.6 μm and 326.55 ± 187.2 μm in the ranibizumab and aflibercept groups, respectively, with no significant difference (p = 0.97). Similarly, the changes in SFCT over 12 months were not significant between the groups (ranibizumab, 41.9 ± 33.0 μm; aflibercept, 43.8 ± 43.8 μm, p = 0.89).

CONCLUSION

The effects of ranibizumab and aflibercept on choroidal thickness in BRVO-ME were the same regardless of the site. Although BRVO is a retinal disease, we hope that we can further explore the mechanism of BRVO-ME by observing changes in the choroid in the future.

The effect of branch retinal vein occlusion on the vascular structure of the choroid

OBJECTIVE

Our aim is to examine choroidal structural changes in eyes with branch retinal vein occlusion (BRVO).

MATERIAL AND METHOD

This retrospective, comparative study included 34 newly diagnosed unilateral BRVO patients and 40 healthy controls. Subfoveal choroidal thickness (SFCT) measurement was performed with enhanced depth imaging optical coherence tomography (EDI-OCT). The images were binarized using the ImageJ software program. Total choroidal area (TCA), stromal area (SA), and luminal area (LA) were calculated from the 1500 µm area. The choroidal vascular index (CVI) was determined as the LA/TCA ratio. All parameter values were compared between the BRVO eye and the fellow eye, and the control group eyes.

RESULTS

Eyes with BRVO had a greater SA compared to both fellow and control eyes; hence, the CVI was lower (p < 0.001). LA did not differ between eyes. TCA, although not statistically significant, was larger in eyes with BRVO than in both fellow and control eyes. SFCT was also greater in eyes with BRVO. No correlation was observed between CVI and SFCT and best-corrected visual acuity (BCVA).

CONCLUSION

BRVO affects the stromal part of the choroid rather than its vascular structure. SA increases due to choroidal exudation that occurs in response to retinal ischemia, and CVI decreases accordingly.