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Coats’ Disease

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Title: Coats’ Disease
Author (s): Tyler Boulter, BS; Charles Calvo, MD; Daniel Churgin, MD
Photographer: Moran Eye Center photography
Date: 08-23-2017
Keywords/Main Subjects: Coats’ Disease, Exudative retinopathy, Pediatric Ophthalmology
Brief Description:
Coats’ disease was first described in 1908 and is an idiopathic, typically unilateral, retinal vasculopathy that manifests with a spectrum of findings which can include retinal telangiectasia, exudation, and exudative retinal detachment.1-4 Coats’ disease shows a male predominance, occurs more often in early childhood, and can lead to vision loss.5 Less commonly, this condition presents in teenagers and young adults with less aggressive features.4 No racial or ethnic preference has been shown.5

Coats’ disease classification and management has evolved over time, changing with advances in imaging techniques. The most recent classification was published by Shields et al. in 2000, and is listed below.3



Figure 1: Fluorescein angiogram of the right eye showing vascular non-perfusion and terminal vascular bulbs

Figure 2: Color fundus photo of the right eye showing diffuse yellow exudation in stage 2B Coats’ disease


Symptoms: Painless gradual vision loss is the primary symptom. The most common signs include: strabismus, leukocoria, and visual impairment.5

Environmental Factors or Other Considerations: No environmental factors have been linked to Coats’ onset or severity.5 Genetic causes have been proposed without any clear evidence.5

Treatment:  The main goal of treatment is to eradicate the telangiectasias and facilitate resolution of exudation, salvaging as much vision as possible. Historically, treatment was based on clinical findings. However, with the advent of wide-field imaging, the first step which guides treatment is now wide-angle fluorescein angiography to identify areas of leakage and capillary dropout. Low power and continuous laser is used to treat leaking vascular abnormalities and low power repeated spots of scatter laser treatment can be used to treat avascular areas of retina. Still investigational is the use of anti-angiogenic treatments, such as those neutralizing the bioactivity of vascular endothelial growth factor (VEGF). One hypothesis being considered for anti-VEGF agents is to reduce the choroioretinal anastomosis that occurs in the macula with macular exudates but this is still conjecture without strong evidence. Cryotherapy is avoided if at all possible. If there are areas of serous fluid consideration to external drainage and laser or cryotherapy to vascular areas is given. In advanced Coats’, external drainage, pars plana vitrectomy and endolaser to leaking vessels with silicone oil may be needed.

Stable cases may be observed.3, 7

However, Coats’ disease has been reported to recur even 10 years after initial diagnosis so life-long observation is recommended.8

Pathophysiology: The exact mechanism remains elusive, but there is some evidence that local retinal hypoxia and/or vascular changes may serve to initiate the disease process.1, 9  In addition, there are studies looking at molecular defects in members of  the Wnt signaling pathway also implicated in other conditions such as familial exudative vitreoretinopathy (FEVR) and persistent fetal vasculature (PFV).

 Differential Diagnosis:  The differential includes: retinoblastoma, retinal capillary angioma, familial exudative vitreoretinopathy (FEVR), retina of prematurity (ROP), persistent fetal vasculature syndrome, pars planitis, ocular toxocariasis, and incontinentia pigmenti. 5



  1. Coats G. Forms of retinal diseases with massive exudation. Royal London Ophthalmic Hosp Rep.1908; 17: 440–525.
  2. Cahill M, O’Keefe M, Acheson R, Mulvihill A, Wallace D, Mooney D. Classification of the spectrum of Coats’ disease as subtypes of idiopathic retinal telangiectasis with exudation. Acta Ophthalmol Scand. 2001; 79(6):596–602.
  3. Shields JA, Shields CL, Honavar SG, Demirci H, Cater J. Classification and management of Coats disease: the 2000 Proctor Lecture. Am J Ophthalmol. 2001; 131(5):572–583.
  4. Smithen LM, Brown GC, Brucker AJ, Yannuzzi LA, Klais CM, Spaide RF. Coats’ disease diagnosed in adulthood. Ophthalmology. 2005; 112:1072–1078.
  5. Originally published in: Hartnett, Mary Elizabeth. Pediatric retina: medical and surgical approaches. 2nd Ed. Philadelphia: Lippincott Williams & Wilkins, 2005.
  6. Gomez Morales A. Coats’ disease. Natural history and results of treatment. Am J Ophthalmol 1965; 60:855-864
  7. Ganesan S, Rishi E. Surgical implications in exudative retinal detachment. Sci J Med & Vis Res. 2017; 35: 29-36.

Acknowledgement: The authors acknowledge Wolters Kluwer/ Lippincott Williams and Wilkins [Pediatric retina: medical and surgical approaches. 2nd Ed. Philadelphia: Lippincott Williams & Wilkins, 2005].

Faculty Approval by: M.E.Hartnett

Copyright statement: Copyright ©2017 Boulter, Calvo, Churgin. For further information regarding the rights to this collection, please visit: