Image credit: The American Academy of Ophthalmology

Lattice degeneration is a common form of peripheral retinal degeneration and is  characterized by localized thinning of the retina, overlying retinal liquefaction, and marginal vitreoretinal adhesion. This condition is linked to atrophic retinal holes, tears, and detachments. It can be found in approximately 6-8% of the general population and is more prevalent in individuals with myopia, affecting around 33% of this group. Lattice degeneration is present in 20-30% of people who experience rhegmatogenous retinal detachment however, only 1% of people with lattice degeneration will develop a retinal detachment.

Postmortem histological examination of lattice lesions have shown three consistent findings:

1- Retinal thinning

2- Vitreous liquefaction overlying the area of retinal thinning

3- Tight vitreoretinal adhesion at the margins of the lesion

Histological study of lattice degeneration
Image credit: The American Academy of Ophthalmology
Interpretation: Stéphane Fitoussi, OD

Atrophic holes:

Atrophic round holes occur within the lattice lesion and likely represent the end-stage of retinal thinning and subsequent dissolution of tissue. These holes rarely progress to a clinical retinal detachment but may develop a small cuff of subretinal fluid originating from the overlying liquefied vitreous. As this cuff typically remains stable over time, it is believed that the overlying liquid vitreous does not communicate with the greater vitreous body. Overall, a small percentage of retinal detachments are caused by lattice degeneration with atrophic holes

Retinal tears:

Retinal tears are believed to stem from traction at the margins of lattice lesions due to tight vitreoretinal adhesion. This traction may originate from a posterior vitreous detachment, and as such, the retinal tear is often on the posterior margin of the lattice lesion (see image below).

Image credit: Brisbane retina, Dr Abhishek Sharma

However, not all retinal tears occurring in eyes with lattice degeneration occur adjacent to a lattice lesion, suggesting that these eyes may be at a generalized increased risk of retinal tears. Estimates for the percentage of tears that do occur adjacent to lattice lesions range widely, from 28% to 82.5%. Overall, the risk of retinal tear occurring adjacent to a lattice lesion is very low, with one study suggesting a 1% incidence after 10 years.

Prognosis:

Eyes with lattice (with or without holes) are at very low risk for retinal detachment overall. Eyes which develop retinal tears, especially following a posterior vitreous detachment, are at risk for retinal detachment and require laser photocoagulation or cryotherapy to treat the horseshoe tear(s).