Coats' Disease

• Described by Georges Coats (Scotland) in 1908
• Unilateral retinal vascular abnormalities and retinal exudation in young males
• Similar to Leber's descripiton of a similar condition in 1912 called Leber's disease

• Idiopathic retinal telangiectasia
• Intraretinal and/or subretinal exudation leading to retinal detachment
• Peripheral retinal nonperfusion
• Vitreous relatively normal
• Sporadic
• No systemic abnormalities
• Unilateral (if bilateral second eye is very mildly affected)
• Male in first or second decade of life
• Xanthocoria

• Retinal tumors
  • hemangioblastoma
  • retinoblastoma
  • choroidal hemangioma
• Exudative vitreoretinopathies
  • Retinopathy of Prematuity
  • Familial Exudative Vitreoretinopathy
  • Norrie disease
• Other causes of leukocoria
  • retinal hemorrhage
  • toxocariasis
  • persistent fetal vasculature
  • coloboma
  • endophthalmitis
  • CMV retinitis
  • toxoplasmosis

Adapted from Shields JA, Shields CL, Honavar S, Demirci H. Classification and management of Coats disease: The 2000 Proctor Lecture. Am J Ophthalmol 2001;131:572-83

• Diode 532nm recommended by Shapiro et al.
  • Power generally 400 to 750 mW
  • Duration 1000 ms
  • Rapid interval cycles to simulate near continuous treatment
  • endpoint: telangiectatic vessel whitening
• Diode 810nm recommended by Villegas et al.
  • Large (1.2 mm) spot size
  • Power typically around 350 mW
  • treat entire surface of telangiectatic vessels and/or exudative detachment as well as the avascular retina.
  • endpoint: complete whitening of the telangiectatic vessels
  • add bevacizumab 1.25 mg

• adjunctive treatment
• 1.25 mg via pars plana

1. Coats disease: An overview of classification, management and outcomes. Indian J Ophthalmolol. 2019 Jun;67(6):763-771
2. Advanced Coats’ disease treated with intravitreal bevacizumab combined with laser vascular ablation. Clinical Ophthalmology 2014:8;973-976
3. https://1drv.ms/b/c/31d83ae8e55e0542/EfAH56QMqQVPhMKbQmtwVVcBCvsKaSRLX-AI2zQoc2dG_w?e=bfAzNc |Effects of Green Diode Laser in the Treatment of Pediatric Coats Disease. Shapiro et al. Am J Ophthalmolol 2011;151:725-731]]
4. Current Management of Coats Disease, Survey of Ophthalmology 2014;59:30-46
5. Selective photocoagulation in Coats’ disease: ten-year follow-up. Eur J Ophthalmol 2002;12:501-5