A 9-year-old boy has reduced vision in the left eye for one year. Fundus examination shows extensive yellow-green subretinal exudation temporally with clusters of retinal telangiectatic vessels. Fluorescein angiography demonstrates marked capillary dilation, microaneurysms, and leakage. Ultrasound shows exudates but no calcification. The MOST likely diagnosis is:
- A Retinoblastoma
- B Best vitelliform macular dystrophy
- C Coats disease ✓
- D Familial exudative vitreoretinopathy
Correct answer: C. Coats disease
Explanation
Coats disease is a unilateral idiopathic retinal telangiectasia with progressive lipid exudation, classically affecting young males. Fluorescein angiography showing telangiectasia, aneurysmal dilatations and bulb-like leakages is diagnostic, and absence of calcification argues against retinoblastoma, the main mimic causing leukocoria in this age group. Best disease is bilateral with an egg-yolk macular lesion and abnormal EOG, and FEVR is familial with peripheral avascularity.
Reference: AAO Basic and Clinical Science Course, Section 12: Retina and Vitreous, 2023-2024 ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.