Optic Neuritis Simulator | Demyelinating Vision Loss Research

Base color

Model & settings

Scotoma model

Vision loss severity50%

Perceptual severity curve Color desaturation (red washing) Uhthoff phenomenon (heat/fatigue)

Image simulation

Choose image Upload JPG/PNG (max 1200×1200). Simulated canvas next to original.

Research notes

Optic neuritis is the most common acquired optic neuropathy in young adults and the presenting feature in ~25% of MS cases. The hallmark central scotoma reflects macular fiber vulnerability to conduction block. Color desaturation — especially red washing ("objects look less red") — is a sensitive early feature. Uhthoff phenomenon (paradoxical worsening in heat or fatigue) is characteristic of demyelinating disease due to temperature- dependent conduction block in incompletely remyelinated fibers. Combined mode adds global contrast attenuation layered over the central scotoma to approximate the full NMOSD-ON or severe MS-ON experience.

Swatches — Reference vs ON Central Scotoma

Reference

HEX: — • RGB: — • xy: —

ON Sim

HEX: — • RGB: — • xy: —

ΔE (CIE76)

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ΔE (CIEDE2000)

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Deep preview

Reference

Simulated

Chromaticity (CIE xy)

Achromatic axis (to D65)

D65 white point: 0.313, 0.329

Image simulation

Simulations operate in linear sRGB for perceptual correctness. ΔE2000 implemented locally. Central scotoma is applied as a Gaussian radial attenuation mask centered at fixation. Diffuse depression mode applies a global luminance scaling factor (like a dimmer) representing widespread axonal conduction block. Color desaturation shifts the chromaticity toward the achromatic point preferentially in the red-green axis, reflecting optic neuritis's characteristic reduction of red desaturation sensitivity. Uhthoff checkbox applies additional global contrast suppression (+20% severity increase) to approximate temperature-dependent conduction block. Use severity slider to blend from normal vision (0%) to severe ON depression (100%).

Multi-condition comparison

Condition A

Condition B

Steps

Compare normal, Condition A and Condition B across multiple severities. If an image is loaded it will be processed into the grid, otherwise color swatches are shown.

Advanced mode

Scotoma size (°)

Scotoma type

Desaturation mode

Clinical notes: MS-ON typically presents with a central scotoma corresponding to loss of macular fibers (central arcuate bundle) due to focal demyelinating plaque within the optic nerve. NMOSD-ON (AQP4-IgG) tends to produce more severe, often bilateral, diffuse or posterior field defects associated with chiasmal or optic tract extension. MOG-IgG-ON has a predilection for anterior nerve and perineuritis pattern, occasionally producing disc swelling. The desaturation mode setting allows approximation of the different color defect axes: red-green preferential in MS-ON; more global in severe NMOSD-ON.

Model assumptions & limits

Scotoma is modeled as a symmetric Gaussian. Real MS-ON scotomas are often irregular, reflecting plaque geometry within the nerve fascicle bundles.
Diffuse depression approximates global conduction block. Real diffuse depression in NMOSD reflects extensive longitudinal nerve inflammation (optic nerve length >1 cm on MRI), which is not geometrically modeled.
Uhthoff simulation is multiplicative severity increase; real Uhthoff effect is a reversible temperature-dependent conduction block that reduces safety factor of action potential generation at demyelinated nodes.
Recovery simulation assumes spontaneous partial remyelination (MS-ON: ~90% recover to 20/40 by 6 months); NMOSD-ON recovery is typically poor and not simulated separately.