Purchase this article with an account.
M. Minami, H. Oku, T. Okuno, T. Kobayashi, T. Yamagami, M. Takagi, T. Sugiyama, T. Ikeda; Experimental Assessment of High Infusion Pressure during Pars Plana Vitrectomy for the Development of Optic Nerve Atrophy after Successful Surgery. . Invest. Ophthalmol. Vis. Sci. 2004;45(13):5488.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To investigate the involvement of high infusion pressure during vitreous surgery in the pathogenesis of optic atrophy after successful operation. Methods: On one eye of albino rabbits, we performed surgery using phacoemulsification and aspiration (PEA) technique followed by pars plana vitrectomy (PPV) under general anesthesia with inpraperitoneal urethane (0.8mg/kg), while the other eye was kept as a control. The animals were divided into two groups after PEA; in one group, intraocular pressure (IOP) was monitored with a pressure transducer and increased to 80 mm Hg by increasing the height of the bottle for 30 minutes (high infusion pressure group, n=6), and in the other group IOP was maintained at 40 mm Hg (low infusion pressure group, n=5). Then, PPV was performed for 15 minutes in both groups under infusion pressure of 40 mm Hg. Functional alterations were assessed by using visually–evoked potentials (VEPs) and electroretinograms (ERGs). After completion of the 10–day experimental period, the animals were killed using intravenous pentobarbital sodium, and the eyes were enucleated and subjected to histological analysis. Damage to retinal ganglion cells (RGCs) was quantified by counting cells in the ganglion cell layer (GCL) in the posterior retina over a distance of approximately 5 mm. Results: In the control eyes, no significant changes were detected in either ERGs or VEPs. Significant changes were not detected in the ERG b–wave amplitudes after the surgery in either high or low perfusion pressure groups. However, elongation VEP implicit times (ITs) of 124 % and 114 % with a reduction in amplitudes by 76 % and 84 % to the baseline were observed 7 and 10 days after the surgery, respectively, in the high infusion pressure group, while no significant changes inVEPs were detected in the low infusion pressure group. Also, the number of GCL cells were significantly reduced from the control levels of 45.3/mm to 24.7/mm in the high infusion pressure group. Conclusions: Possible involvement of high infusion pressure during PPV in the development of optic nerve atrophy was experimentally suggested.
This PDF is available to Subscribers Only