A Guide to Posterior Eye Pathology: Key Conditions Explained

Here’s a concise summary of the key points from our Posterior Eye Pathology webinar.

Diabetic Retinopathy

Diabetes affects the body’s smallest blood vessels, including those in the eyes. High blood sugar damages these vessels, making them fragile and prone to leakage. When oxygen delivery to the retina decreases, the body tries to grow new vessels, but these are brittle, often breaking and leading to bleeding and scarring.

Signs to look for:

• R1 (background): Microaneurysms, dot-and-blot haemorrhages
• R2 (pre-proliferative): Cotton wool spots, venous beading/looping, flame haemorrhages
• R3 (proliferative): Neovascularisation, pre-retinal haemorrhages

Maculopathy (M1): Exudates near the macula may threaten central vision.

Management:

• R1: Monitor
• R2: Routine referral
• R3: Urgent referral → possible laser (PRP), vitrectomy, or anti-VEGF
• M1: Consider anti-VEGF, focal laser, or steroid injections

Hypertensive Retinopathy

High blood pressure causes thickening of arterial walls, narrowing blood flow to the retina. Over time, this leads to vessel changes, haemorrhages, and optic nerve swelling in severe cases.

Grading:

• Grade 1: Generalised narrowing
• Grade 2: Focal narrowing, AV nipping, “copper wiring”
• Grade 3: Haemorrhages, exudates, cotton wool spots, macular star
• Grade 4: Severe changes + optic disc swelling (emergency)

Referral:

• Undiagnosed hypertension/diabetes → GP
• Retinal vascular changes → ophthalmology
• Papilledema → emergency referral

Age-Related Macular Degeneration (AMD)

• Dry AMD: Characterised by drusen and, in later stages, geographic atrophy.
  • Management: Lifestyle advice (AREDS2 supplements, leafy greens, UV protection, no smoking), monitoring with Amsler grid.
• Wet AMD: Caused by abnormal vessel growth and leakage under the macula.
  • Management: Anti-VEGF injections, sometimes laser.

Retinal Detachment

The vitreous gel can pull on the retina, creating tears that allow fluid to leak underneath, causing detachment.

Types:

• Rhegmatogenous: Caused by retinal tear
• Exudative: Fluid from underlying conditions (e.g., AMD, tumours)
• Tractional: From scarring (e.g., uncontrolled diabetes)

Key signs:

• Flashes (brief, peripheral “lightning” due to traction)
• Floaters (clumped cells casting shadows)
• Schaefer’s sign (pigmented cells in vitreous, “tobacco dust”)

Management:

• Urgent referral if retinal tear/detachment suspected
• Surgery may include vitrectomy with gas/oil

Other Posterior Pathologies

Epiretinal Membrane (ERM)

• A fibrocellular “sheet” over the retina, often after PVD.
• Symptoms: Distorted or blurred central vision.
• Management: Observation if mild; vitrectomy + membrane peel if severe.

Central Serous Retinopathy (CSR)

• Fluid buildup under the macula, often linked to stress.
• Usually resolves in 1–6 months; persistent cases may need laser, photodynamic therapy, or anti-VEGF.

Macular Holes

• Graded by OCT into stages 1–4.
• Symptoms: Central vision loss.
• Management: Monitoring for early holes; vitrectomy with gas for larger/full-thickness holes.

Best Disease (Vitelliform Macular Dystrophy)

• Juvenile inherited macular dystrophy.
• Classic “egg yolk” appearance progressing to scrambled-egg-like changes.
• Adult-onset form is milder but can mimic AMD.

Key Takeaways

• Systemic health (diabetes, hypertension) has a major impact on eye health.
• Recognising early signs of retinopathy or macular disease allows for timely referral and intervention.
• Patient education, explaining complex processes in simple terms helps individuals understand the importance of controlling systemic risk factors.