Macroaneurysm — EyeWiki

Citation

EyeWiki Contributors. “Macroaneurysm.” EyeWiki, American Academy of Ophthalmology. Accessed 2026-04-14. https://eyewiki.org/Macroaneurysm

Key references within the article:

• Moorsavi RA et al. Retinal artery macroaneurysms: clinical and fluorescein angiographic features in 34 patients. Eye (Lond) 2006.
• Fichte C et al. A histopathologic study of retinal arterial aneurysms. Am J Ophthalmol 1978.
• Xu L et al. Frequency of retinal macroaneurysms in adult Chinese: the Beijing Eye Study. Br J Ophthalmol 2007.
• Pichi F et al. Intravitreal bevacizumab for macular complications from retinal arterial macroaneurysms. Am J Ophthalmol 2013.

Key Findings / Takeaways

• RAM = acquired focal dilation of retinal arterial branches, mostly 2nd-order arterioles, 100–250 μm diameter
• Classified as hemorrhagic or exudative — this distinction affects prognosis and management
• Most common location: superotemporal arcade
• Strong association with hypertension (75% of patients), elderly, female predominance
• Incidence: ~1 per 9000 eyes (Beijing Eye Study); 10% bilateral in hemorrhagic type
• Histopathology: vessel wall thickening, fibrin, foamy macrophages — resembles age-related arteriosclerotic changes
• Linear breaks in arterial walls → round or fusiform dilation → hemorrhage/exudation at any retinal level
• Multilevel hemorrhage (preretinal + intraretinal + subretinal) is a hallmark diagnostic clue — shared only with anemic/leukemic retinopathy and shaken baby syndrome
• FFA: saccular type fills mid-to-late phase; fusiform type fills early phase; vessel wall staining with possible late leakage
• SD-OCT useful for quantifying exudates in the exudative type
• Prognosis: most regress spontaneously; hemorrhagic type has better prognosis than exudative; worst prognosis with persistent macular edema or subretinal hemorrhage
• Laser photocoagulation: controversial — moderate-intensity, large-spot (200–500 μm) adjacent to aneurysm; risk of BRAO in up to 16% of cases
• Anti-VEGF (bevacizumab, ranibizumab): promising for macular edema (Pichi et al. — 38 eyes showed reduction in edema and hard exudates), but not extensively studied
• Submacular hemorrhage: pneumatic displacement ± tPA
• Premacular hemorrhage: Nd:YAG posterior hyaloidotomy to release blood into vitreous
• No approved management guidelines exist

Clinical Implications

• Hypertension workup is mandatory in every RAM patient
• Multilevel hemorrhage on fundoscopy → think RAM (high-yield exam point)
• Observation is first-line; intervene only when macula threatened
• Laser carries real risks — BRAO in 16% — so anti-VEGF may become preferred for macular edema cases as evidence grows
• Secondary RAM can occur with branch-retinal-vein-occlusion, diabetic-retinopathy, radiation-retinopathy, retinal arteritis — always look for underlying cause

Entities Mentioned

• retinal-arterial-macroaneurysm — primary entity
• hypertensive-retinopathy — strongest systemic association
• bevacizumab — treatment for macular edema
• ranibizumab — treatment for macular edema
• branch-retinal-vein-occlusion — secondary cause / differential
• diabetic-retinopathy — secondary cause
• radiation-retinopathy — secondary cause
• coats-disease — differential diagnosis
• von-hippel-lindau — differential diagnosis
• vitreous-hemorrhage — complication / presenting feature

Concepts Covered

• fluorescein-angiography — diagnostic: filling patterns, leakage
• oct-interpretation — quantifying exudation
• laser-photocoagulation — treatment modality
• pneumatic-displacement — submacular hemorrhage management
• intravitreal-injections — anti-VEGF delivery
• yag-posterior-hyaloidotomy — premacular hemorrhage management

Contradictions / Updates

• None vs existing wiki content (first source ingested in vascular diseases domain)