Lattice degeneration is a common finding involving localized thinning of the peripheral retina, the light-sensitive tissue at the back of the eye. Although it is present in a significant portion of the general population, most people are unaware they have it because it typically causes no noticeable symptoms. Understanding this condition is important primarily because of its association with the serious, vision-threatening complication known as retinal detachment.
Defining Lattice Degeneration
Lattice degeneration is an acquired, degenerative disorder characterized by distinct, oval or linear patches of atrophy in the far outer edges of the retina. This thinning affects the full thickness of the retina. The term “lattice” comes from the appearance of fine, crisscrossing white lines often visible within these thinned areas, which are actually sclerotic, or hardened, blood vessels.
These lesions are typically found in the vertical meridians of the eye, located between the equator and the ora serrata, the edge where the retina ends. The thinning may also be accompanied by pigment clumping. Lattice degeneration is often found in both eyes (affecting 30–50% of individuals who have it in one eye) and is typically discovered incidentally during a routine dilated eye examination.
Risk Factors and Associated Conditions
While the precise cause of lattice degeneration remains unknown, the condition is found in approximately 6–10% of the general population. The most significant risk factor is nearsightedness, or myopia, especially when severe.
In myopic eyes, the eyeball is longer than average, stretching the retinal tissue and contributing to peripheral thinning. Lattice degeneration frequently clusters within families, suggesting a genetic component. It is also associated with rare, hereditary connective tissue disorders, such as Marfan syndrome, Ehlers-Danlos syndrome, and Stickler syndrome, which cause generalized tissue fragility.
The Primary Risk: Retinal Tears and Detachment
Lattice degeneration is the most significant peripheral retinal change that increases the risk of retinal detachment. The danger arises from the interaction between the thinned retina and the vitreous humor, the gel filling the center of the eye. As a person ages, the vitreous gel naturally liquefies and shrinks, leading to a posterior vitreous detachment (PVD), where the gel separates from the retina.
In a person with lattice degeneration, the vitreous remains abnormally and firmly attached at the edges of the thinned lesions. The normal shrinkage and separation of the vitreous gel creates a strong pulling or tractional force on these adhered areas of weakened retina. This traction can cause a full-thickness break, known as a retinal tear, often shaped like a horseshoe.
Once a retinal tear forms, liquefied vitreous fluid can pass through the opening and accumulate beneath the retina, causing it to peel away from the underlying tissue. This separation is a retinal detachment, which interrupts the blood supply and nutrient exchange, leading to permanent vision loss if not addressed quickly. Despite the risk, the overall chance for any single person with the condition to develop a retinal detachment is low, estimated at less than one percent.
A sudden appearance of symptoms indicates a tear or detachment may be occurring, requiring emergency medical attention. Urgent warning signs include a sudden increase in floaters—small, dark specks or cobweb-like shapes—that drift across the field of vision. Flashes of light, called photopsia, are also common, representing the vitreous pulling on the sensitive retina. A shadow or dark curtain obscuring vision signifies that a portion of the retina has already detached.
Monitoring and Treatment Options
Lattice degeneration itself typically does not require intervention; the primary management strategy is careful monitoring through regular, comprehensive eye examinations. A dilated fundus examination allows the specialist to view the entire peripheral retina in detail to check for new tears or holes. Patients with stable lattice degeneration are advised to remain vigilant for symptoms of a tear or detachment and to continue with annual or biannual check-ups.
Preventive treatment is reserved for specific, high-risk situations, such as when a retinal tear is already present within the lattice area. Treatment may also be considered if the patient has lattice degeneration in one eye and has previously experienced a retinal detachment in the other. The standard procedure involves laser photocoagulation, which uses a precisely targeted laser to create tiny burns that form scar tissue around the edges of the lesion. This scarring creates a strong adhesion, effectively walling off the weakened area to prevent detachment.