Base color

Model & settings

Scotoma model

Vision loss severity50%

Perceptual severity curve Acquired dyschromatopsia Gradual scotoma edge

Image simulation

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

Research notes

LHON results from point mutations in mitochondrial DNA encoding Complex I (NADH dehydrogenase) subunits. The three primary mutations — m.11778G>A (ND4, ~70%), m.3460G>A (ND1, ~13%), and m.14484T>C (ND6, ~14%) — impair the electron transport chain in retinal ganglion cells, whose long unmyelinated axons are highly metabolically vulnerable. Gradual scotoma edge simulates the expanding lesion margin during the subacute conversion phase. Dyschromatopsia mode desaturates colors along the red-green axis, a characteristic LHON feature.

Swatches — Reference vs LHON Central Scotoma

Reference

HEX: — • RGB: — • xy: —

LHON 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, scaled by angular scotoma radius in degrees. Cecocentral mode extends the mask from the blind spot to the fovea along the papillomacular bundle trajectory. Dyschromatopsia desaturates along the red-green (protan/deutan) axis, reflecting LHON's characteristic acquired color defect. Use the severity slider to blend from normal (0%) to dense central scotoma (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 radius (°)

Scotoma edge

Color axis

Clinical notes: The cecocentral scotoma connects the blind spot (physiological scotoma at 15° temporal) to the fixation point along the papillomacular bundle — the fiber trajectory most vulnerable in LHON due to high mitochondrial density in small-calibre axons. Ring scotoma mode simulates partial spontaneous recovery (most common with m.14484T>C mutation, ~50% recover to 20/200 or better). Red-green dyschromatopsia is the characteristic LHON color defect; blue-yellow axis may predominate in some m.3460G>A carriers.

Model assumptions & limits

Central scotoma is modeled as a radially symmetric Gaussian; real LHON scotomas are often horizontally elongated along the papillomacular bundle axis.
Cecocentral extension is a horizontal ellipse approximation; the real PMB trajectory follows a curved arcuate path from the optic disc.
Dyschromatopsia is a global post-processing desaturation; real color defects in LHON are spatially heterogeneous and axis-dependent.
Recovery simulation (ring mode) is a phenomenological approximation; real recovery is driven by mitochondrial heteroplasmy shifts and spontaneous rescue of surviving ganglion cells, which is not modeled.