COAT’S DISEASEDr. Lanin Chen

Resident, Dept. of OphthalmologyD. Y. Patil Medical College, Navi Mumbai.

INTRODUCTION First described by George Coats in 1908. Coats’ disease is an idiopathic condition characterized

by retinal vascular changes and exudation caused by a defect in retinal vasculature development.

Increased permeability of abnormal retinal vessels causes leakage into the intraretinal and subretinal spaces.

Males: Females :: 3:1 80% are unilateral 2/3rd cases present before 10 years of age No predilection for race

CLASSIFICATION

Shields, JA et al. Classification and Management of Coats Disease: the 2000 Proctor Lecture. Am J Ophthalmology. 2001;31(5):572-583. 

CLINICAL FEATURESSYMPTOMS Blurred vision Photopsia Floaters Red eye effect

SIGNS Leucocoria Strabismus Corneal Oedema Iris

neovascularization Heterochromia

FUNDUS EXAMINATION Telengiectasia Intraretinal

exudation Exudative RD Partial RD Total RD Retinal hemorrhage Retinal macrocyst

DIFFERENTIAL DIAGNOSIS Retinoblastoma Retinal detachment Persistent hyperplastic primary vitreous Congenital cataract Norrie’s disease Eale’s disease Vasculitis Tumour with exudation Idiopathic juxtafoveal telangiectasia

DIAGNOSTIC TESTS FFA USG - Hyperechoic mass in the posterior vitreous without posterior

acoustic shadowing. Vitreous and subretinal hemorrhage may be seen.

CT Scan - The globe appears hyperdense compared to the normal vitreous due to the proteinaceous exudate, which may obliterate the vitreous space in advanced disease. The anterior margin of the subretinal exudate enhances with contrast. Since the retina is fixed posteriorly at the optic disc, this enhancement has a V-shaped configuration.

MRI - The subretinal exudate shos high signal intensity on both T1 and T2 weighted images. The exudate may appear heterogenous if hemorrhage or fibrosis is present. The subretinal space does not enhance with gadolinium constrast. Mild to moderate linear enhancement may be seen between the exudate and the remaining vitreous.

FFA

TREATMENTThe major goal of treatment in Coats' disease is

to preserve or improve visual acuity or, when this is impossible, to preserve the anatomical integrity of the eye.

Treatment generally consists of photocoagulation, cryotherapy, and in severe cases, retinal reattachment surgery.

Anti-VEGF injections have been successfully used as part of combination therapy in case series but there is a risk of vitreo-retinal traction.

TREATMENT MODALITIES Stage 1 – periodic observations / laser

photocoagulation Stage 2 – Laser photocoagulation /

cryotherapy Stage 3A – Retinal re-attachment surgery /

laser photocoagulation Stage 3B – Retinal re-attachment surgery

/Cryotherapy Stage 4 – Enucleation Stage 5 – No aggressive treatment

TREATMENT Intravitreal triamcinolone acetonide

Effective in macular oedema and subretinal exudation.

Intravitreal Anti-VEGF agentsReduces subretinal fluid and macular

exudation. Surgical Intervention

in cases of traction, hemorrhage, retinal detachment, painful blind eye.

THANK YOU

REFERENCES:1. Shields, JA et al. Classification and Management of Coats

Disease: the 2000 Proctor Lecture. Am J Ophthalmology. 2001;31(5):572-583. 

2. Kanski, Jack J. Clinical Ophthalmology: A Systematic Approach. 6th ed. Elsevier Ltd., 2007.