Characteristics and Prognosis of Retinal Detachments with Demarcation Lines

Abstract

In longstanding retinal detachments, retinal pigment epithelial cells can prolif­ erate and undergo metaplasia at the junc­ tion of attached and detached retina, forming what is clinically known as a demarcation line. We reviewed 553 cases of consecutive retinal detachments to de­ termine the characteristics and prognosis of detachments with demarcation lines. Demarcation lines are present in 16.7% of phakic and 13.5% of aphakic retinal detachments. Clinically, a demarcation line appears either as a line of pigmenta­ tion at the junction of attached and de­ tached retina, or in the detached area of the retina as a line of subretinal fibrous tissue concave to the ora serrata. The metaplastic retinal pigment epithelial cells may produce a fibrous adhesion to the retina. In some cases this adhesion prevents progression of the retinal de­ tachment, but a demarcation line cannot be regarded as continued protection against further spread of the detachment. Most retinal detachments with demar­ cation lines are of at least three months' duration. Longstanding retinal detach­ ments may progress to massive periretinal proliferation (ΜΡΡ) more readily than those of shorter duration. Massive perire­ tinal proliferation is also known as mas­ sive preretinal retraction (MPR), or mas­ sive vitreous retraction (MVR); it is the most common cause of failure of retinal detachment surgery. In massive periretin­ al proliferation, pigment epithelial cells