Retina - Other

---

When a storm is brewing inside of the vitreous, how do you get to the destination safely? Before the 1995 EVS study, there was no clear consensus on how to utilize vitrectomy and IV antibiotics for patients with post-op endophthalmitis. Therefore, the EVS study sought to define a treatment protocol for these scary cases. In the study, 420 patients with clinical evidence of endophthalmitis within 6 weeks after cataract surgery or secondary intraocular lens implantation were randomly assigned to four groups with combinations of pars plana vitrectomy PPV or no PPV, and treatment with or without systemic antibiotics.

Key Points:

• Systemic antibiotics may not be necessary and increase cost, length of stay, and toxic side effects
• Routine PPV is not necessary for patients with better than light perception (LP) vision at presentation
• PPV is beneficial for patients presenting with LP or worse vision, leading to better visual outcomes and reduced adverse outcomes 

Overall, EVS established an LP cutoff for routine PPV in post-op endophthalmitis. If a patient can see HM, you can wave them goodbye instead of taking straight to the OR.

Corticosteroids reduce macular edema in patients with retinal vein occlusion? SCORE! The Standard Care vs Corticosteroid for Central Retinal Vein Occlusion (SCORE-CRVO) sought to determine the optimal treatment for vision loss associated with macular edema secondary to perfused central retinal vein occlusion (CRVO). 271 patients from 66 clinical sites were randomized to three groups: observation (n=88), 1mg intravitreal triamcinolone (n=92), 4mg intravitreal triamcinolone (n=91). Participants were retreated at 4-month intervals for 36 months. 

Key Points:

• The likelihood of a 15 letter gain in visual acuity at 1 year was five times greater with 1mg intravitreal triamcinolone (95% CI, 1.8-14.1; P=.001) and 4mg intravitreal triamcinolone (95% CI, 1.8-14.4; P=.001) compared to the observation group
• Unlike visual acuity, no significant difference was found in retinal thickness between groups at 12 months
• There was a dose-dependent relationship to the need of initiating IOP-lowering medications with triamcinolone (41% in the 4-mg group and 7% in the 1-mg group) compared with the standard-care group (2%)

Overall, the SCORE-CRVO is a landmark study because it led to a major shift in the treatment of vision loss associated with macular edema secondary to CRVO. Prior to this study, there was no proven, effective treatment for this condition and the standard of care was observation. The results demonstrate both 1-mg and 4-mg intravitreal triamcinolone had better visual acuity outcomes over 12 months compared to the untreated natural course of disease. Given the safety profile of the low dose, particularly with respect to glaucoma and cataract, 1-mg intravitreal triamcinolone became the preferred treatment of macular edema in patients with CRVO. Shortly after this study, however, another set of Landmark studies (BRAVO & CRUISE) enlightened us to even more effective treatment options.

Keep your friends close, but your anti-VEGF injections closer… The BRAVO and CRUISE trials looked to find the best course of treatment for macular edema in the setting of branch and central retinal vein occlusions. Prior to this, laser therapy had proven to be ineffective and patients were simply observed with little hope in visual improvement. In the BRAVO and CRUISE trials, patients with macular edema following BRVO (n=397) and CRVO (n=392) were randomized to receive monthly intravitreal injections of 0.3 or 0.5 mg of ranibizumab or sham injections.

Key Points:

• For BRVO, an increase in at least 15 letters in BCVA at 6 months was seen in 55.2% (0.3 mg) and 61.2% (0.5 mg) of patients compared to only 28.8% in the placebo arm; for CRVO, the respective groups yielding 46.2% (0.3 mg), 47.7% (0.5 mg), and 16.9% (placebo)
• Central foveal thickness at 6 months following BRVO/CRVO had decreased by a mean of 337/434 mircons (0.3 mg) and 345/452 microns (0.5 mg) in the ranibizumab groups compared to 158/168 mircons in the placebo grou
• The BRAVO trial saw more placebo patients (54.5%) receive rescue grid laser compared with the 0.3 mg (18.7%) and 0.5 mg (19.8%) ranibizumab groups

The importance of this study was showing that anti-VEGF injections were effective in treating macular edema following retinal vein occlusions leading to marked improvement in visual acuity while still maintaining a very low risk of complications.