Ophthalmoscopic model of nerve fiber bundle defects in monkey eyes produced by intraocular retinal coagulation

The development of nerve fiber bundle defects in monkey eyes by means of intraocular retinal coagulation, such as endodiathermy, intraocular cryotherapy or endophotocoagulation was confirmed by ophthalmoscopy. Two to 4 days after the application of intraocular retinal coagulation, the findings could be already observed. Endodiathermy especially could provide the typical ophthalmoscopic findings of nerve fiber bundle defects without any abnormal fluorescein angiographic findings, while endophotocoagulation and intraocular cryotherapy induced hyperfluorescence due to window defect at the coagulation site. Therefore, endodiathermy in monkey eyes can provide an excellent ophthalmoscopic model of the nerve fiber bundle defects. Histological findings 8 weeks after the coagulation showed thinning of the retinal nerve fiber layer and gliosis occurring in the retinal portion corresponding to the lesion.