Dr Ben Wild
Overview |
Our vision comes from light waves stimulating retinal photoreceptors and these photoreceptors transferring their signals through the several different cells in the retina and onwards to the brain. For light to focus on the retina, it must pass through the cornea (front of the eye), the pupil, then lens and the clear vitreous humor gel.
Sagittal view of a healthy eye.
Lattice and snail track degenerations are mostly bilateral (both eyes) conditions thought to develop early in life (2nd or 3rd decade) most commonly in people who have moderate to high nearsightedness. Simply put, they are like stretch marks on the retina. Snail tracks are white spindle shaped areas of retinal thinning. It is thought that this thinning then leads to pulling of the retina by the vitreous humor gel leading to lattice formation. Lattice presents as spindle shaped pigmented lines on the retina, often with white blood vessels overtop, often with retinal holes nearby, and liquefied vitreous gel overtop known as lacunae.
Lattice degeneration is the most important degeneration linked to retinal detachments as 40% of all retinal detachments occur in eyes with lattice degeneration although only 1% of eyes with lattice degeneration develop a retinal detachment.
A sagittal view of an eye with snail track degeneration (white) and lattice degeneration (black) with a retinal hole nearby.
Signs and Symptoms |
Signs
Snail Track | White spindle shaped lines in the retina. |
Lattice | Spindle shaped lines of dark pigment in the retina, possible retinal holes nearby, white blood vessels overtop. |
Symptoms
Asymptomatic (no symptoms).
Causes and Risk Factors |
Causes
Thin retina due to genetics or due to overgrowth of the eye (nearsightedness).
Risk Factors
Genetics, nearsightedness.
Prevention and Treatment |
Prevention
There are no known preventative measures.
Treatments
· Close monitoring every 1-2 years for development of a retinal hole or tear.
· If a retinal hole or tear occurs; laser retinopexy surgery.
Prognosis |
Neither snail track nor lattice degeneration affect vision. Vision is only affected if the degeneration leads to a retinal hole or tear and then a retinal detachment. Holes and tears can usually be treated with retinal laser surgery without any affects on vision but if a retinal detachment occurs, long-term vision will be permanently affected.
For either lattice or snail track degeneration, seek medical attention same day with any new flashes of light, floaters or a veil appearance in vision.