Vision Loss
1. Sudden or gradual vision loss?
- sudden: vascular occlusion or bleeding
- gradual: degenerations or depositions
2. Associated with pain?
Associated pain is a common finding in anterior ocular processes. Other painful conditions: orbital disease, optic neuritis, and giant cell arteritis.
3. Transient or persistent vision loss?
- transient: temporary/subcritical vascular insufficiency or papilledema
- persistent: structural or irreversible damage to the
4. Unilateral or Bilateral vision loss?
- unilateral: a local cause or lesion anterior to optic chiasma
- bilateral: a more widespread or systemic process or lesion posterior to optic chiasma
5. Blurred, dimmed or distorted vision (What)?
- blurring or dimming: pathology anywhere in the visual pathway from cornea to cortex; common problems include refractive error, cataract, and macular disease.
- distortion: macular pathology, high refractive error (high ametropia/astigmatism) or other ocular disease.
6. Where is the vision loss?
- superior or inferior hemispheric field loss (Altitudinal): corresponding inferior or superior vascular event involving the retina (e.g., retinal vein occlusion) or optic disc (e.g., segmental AION)
- peripheral field loss: retinal detachment (usually rapidly evolving from far periphery), optic nerve disease, chiasmal compression (typically bitemporal loss), or cortical pathology (homonymous hemianopic defects)
- central blurring of vision: diseases of the macula (positive scotoma: a “seen” spot) or optic nerve (negative scotoma: an unseen defect).
7. When is the vision loss?
- glare: from headlights or bright sunlight due to posterior subcapsular lens opacities. Further investigations are based upon the disease suspected from history and ophthalmic examination.