DISCIFORM SCAR

Disciform scar is the final scar stage of wet AMD or other causes of choroidal neovascularization (CNV). It’s basically the eye’s “healing” response after a bleed under the macula, but the scar damages central vision.

What it is

  • Definition: A gray-white, disc-shaped fibrous scar under the retina in the macular area
  • Size: Usually 1-5 mm wide, right where you need sharp vision
  • Tissue: Made of fibrous tissue, blood vessels, and pigment after a CNV membrane closes off

How it forms

  1. CNV develops: Abnormal blood vessels from the choroid break through Bruch’s membrane into the subretinal space
  2. Leakage and bleeding: Those vessels are fragile. They leak fluid and blood under the macula
  3. Inflammation + scarring: Your body tries to heal the bleed. Fibroblasts lay down collagen and the CNV becomes fibrotic
  4. RPE disruption: Retinal pigment epithelium clumps or dies, leaving pigment changes around the scar
  5. End stage: Active leakage stops, but the scar remains. This whole process takes weeks to months

Main causes

  • Wet age-related macular degeneration: Most common cause. Seen in patients 60+
  • Pathologic myopia: Can also end in a disciform scar, but in younger myopes it’s often called a Fuchs spot
  • Ocular histoplasmosis: POHS can cause CNV and scarring
  • Trauma or inflammation: Any CNV that bleeds can end this way if untreated

Appearance on exam

  • Color: Gray-white to yellow-white central lesion
  • Shape: Round or oval, “disc” like
  • Surrounding changes: Pigment clumps, atrophy, or lipid deposits at the edges
  • Size: Correlates with how bad vision loss is. Larger = worse

Symptoms

  • Central vision loss: Permanent blur or blank spot in the middle of vision
  • Distortion first: Before scar forms, patients report wavy lines from fluid. After scarring, it’s replaced by a fixed blind spot
  • Peripheral vision stays: You won’t go completely blind. Side vision is normal
  • Contrast loss: Reading and faces are hard even if acuity isn’t terrible

Diagnosis

  • Dilated fundus exam: Doctor sees the pale elevated scar
  • OCT scan: Shows hyperreflective subretinal material, loss of outer retinal layers, RPE disruption
  • Fluorescein angiography: Early CNV leaks. Late disciform scar stains but doesn’t leak because vessels are closed
  • History: Patient usually describes sudden vision drop months earlier from a bleed

Treatment

  • No reversing the scar: Once formed, the tissue is fibrotic and vision doesn’t return
  • Goal is prevention: Anti-VEGF injections like Avastin, Eylea, Vabysmo treat active wet AMD before it scars
  • Too late if scarred: Injections don’t help a mature disciform scar
  • Low vision rehab: Magnifiers, better lighting, eccentric viewing training to use peripheral retina

Disciform scar vs Fuchs spot
Feature Disciform scar Fuchs spot
Main cause Wet AMD Myopic CNV
Age 60+ usually 30s-50s
Color Gray-white fibrous Dark pigmented
Eye shape Normal axial length Long, >26.5 mm
Bilaterality Second eye at risk in 4-7 years Second eye at risk in 30-35%
Prognosis

  • Vision: Usually 6/60 or worse if the scar is subfoveal. If it’s off center, vision may be 6/12 to 6/24
  • Stability: Scar doesn’t grow, but geographic atrophy can develop around it
  • Other eye: High risk of wet AMD in fellow eye. Regular monitoring with Amsler grid and OCT is key

Bottom line: A disciform scar is the “tombstone” of wet AMD. Modern anti-VEGF therapy has made them much less common because we can shut down CNV before it bleeds and scars. That’s why sudden distortion or vision drop needs an urgent retina check.