Purpose: To compare the healing process of the retinal pigment epithelium (RPE) with and without the overlying sensory retina.
Methods: A dome-shaped retinal detachment was created in the pigmented rabbit eye by injecting balanced salt solution into the subretinal space. The detached retina was partially removed with a vitrector; in some eyes, the detached retina was removed completely. RPE about 1.5 mm in diameter was removed from Bruch's membrane and aspirated through the retinal break. All eyes were examined morphologically.
Results: Independent of the sensory retina, 4 days postoperatively the RPE wound was covered by immature RPE cells that gradually formed an epithelial-like sheet by 2 weeks postoperatively. In eyes with overlying sensory retina, regenerated RPE cells similar to normal RPE cells formed a monolayer in most areas. The RPE-photoreceptor outer segment interface gradually organized. In eyes with no sensory retina, the regenerated RPE cells were longer, mounded, and their microvilli were shorter and disorganized. The RPE cells were multilayered in some areas and often had a tubuloacinar structure.
Conclusions: The RPE wounds healed rapidly, independent of the presence of the overlying sensory retina, up to 2 weeks after RPE removal. Reconstruction of the RPE monolayer and the apical morphology of regenerated RPE cells were influenced by the sensory retina.