Purpose To assess visual outcomes of Coats disease by classification stage.

Methods A retrospective review was conducted on consecutive patients with Coats disease, classified according to Shields classification and with available Snellen visual acuity before and after treatment.

Results There were 160 eyes with Coats disease (stage 1 (n=2) vs stage 2A (n=17) vs stage 2B (n=22) vs stage 3A1 (n=26) vs stage 3A2 (n=40) vs stage 3B (n=42) vs stage 4 (n=9) vs stage 5 (n=2)). By comparison, more advanced stage showed greater frequency of poor presenting visual acuity (<20/200) (0% vs 0% vs 50% vs 35% vs 38% vs 83% vs 100% vs 100%, p<0.001) and higher mean intraocular pressure (17 vs 15 vs 15 vs 15 vs 15 vs 15 vs 37 vs 26, p<0.001). More advanced stage was less likely managed with laser photocoagulation (100% vs 87% vs 48% vs 62% vs 74% vs 35% vs 0% vs 0%, p<0.001) and more likely with cryotherapy (0% vs 47% vs 81% vs 81% vs 82% vs 88% vs 50% vs 100%, p=0.001). More advanced stage was associated with lower frequency of visual acuity ≥20/40 (100% vs 71% vs 5% vs 42% vs 23% vs 5% vs 0% vs 0%, p<0.001) and greater frequency of visual acuity <20/200 (0% vs 12% vs 36% vs31 % vs 45% vs 88% vs 0% vs 100%, p<0.001).

Conclusion Visual acuity in eyes with Coats disease parallels staging with more advanced stage demonstrating poorer visual acuity at presentation and final visit.