Retinal pigment epithelial wound healing in vivo
P. F. Lopez, Q. Yan, L. Kohen, N. A. Rao, C. Spee, J. Black and A. Oganesian
Department of Ophthalmology, University of Southern California School of Medicine, Los Angeles, USA.
OBJECTIVE: To develop an in vivo rabbit model of retinal pigment epithelial
wound healing that preserves the overlying retina. METHODS: Hydraulic
debridement of the retinal pigment epithelium was performed in one eye of
35 pigmented rabbits by means of a pars plana vitrectomy approach. Five of
the 35 eyes were examined by stereoscopic color fundus photography,
fluorescein angiography, and light microscopy on each of the following
postoperative days: 0, 2, 4, 7, 14, 28, and 56. RESULTS: Retinal pigment
epithelial debridement with this technique results in apical decapitation
of the retinal pigment epithelial cells followed by subsequent hydraulic
removal of the residual nucleus-containing basal cellular debris. The
retinal pigment epithelium-denuded Bruch's membrane was resurfaced mostly
by a monolayer of flattened, hypopigmented retinal pigment epithelial cells
within 4 days after debridement. Progressive retinal pigment epithelial
hyperplasia also occurred beginning between postoperative days 2 and 4.
CONCLUSIONS: Retinal pigment epithelial wound healing after hydraulic
debridement occurs rapidly and in a manner initially consistent with
sliding migration. Progressive retinal pigment epithelial hyperplasia also
occurs and may contribute to this repair process. Further investigation of
retinal pigment epithelial repair by means of this in vivo model may
provide important insight into the pathogenesis and treatment of outer
retinal disorders.
