Purchase this article with an account.
J. Kumar; A New Approach to Develop a Real Time Perfusion System . Invest. Ophthalmol. Vis. Sci. 2006;47(13):416.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Improvement of perfusion systems with the modern technologies is the key to understanding critical issues related to the regulation of aqueous outflow in enucleated cadaver eyes. Thus the goal of the present study was to improve on existing, whole eye perfusion system.
The conventional approach of perfusion system is equipped with the old device constituted of a pair of balance and hanging cups to measure aqueous outflow facility. I have developed a new approach that utilizes a highly sensitive digital balance, AB135–S (Mettler Toledo, OH), attached to fixed reservoirs, having feature to reduce evaporation, on the balance pans instead of hanging buckets. The reservoir on the balance is filled up initially, and, the real time acquisition of flow data corresponding to weight loss is recorded directly using Balance Talk XL 5.1(Labtronics Inc,Canada) software. This system has also capability to measure outflow facility in two pairs of eyes at a time, and provides options to adopt either the Grant corneal fitting device and/or needle insertion in the anterior chamber of the whole eye. To validate this system, we tested the effect of H–7 (100µM) on outflow facility in porcine eyes. In addition, we compared the effect of conventional perfusion medium (PBS plus glucose) and Optimedia (Gibco, NY), on outflow facility.
The flow graphs between the weight loss vs. time on balance talk XL software appeared as straight line consistently thereby eliminating any concerns with respect to leakage in the system. In addition to the outflow facility measurements, the software allows us to quantify the flow data in real time per second to evaluate whether the flow is continuous or discontinuous. Consistent with earlier findings, the outflow facility in the presence of H–7 in PBS was 50% higher as compared to basal value. In sham controls, the outflow facility was similar regardless of whether the perfusion was performed in PBS or Optimedia. However, of significance is our finding that the outflow facility in the presence of H–7 was three times greater in Optimedia as compared to the same set of experiment performed using PBS plus glucose as perfusion media.
This study suggests that the Optimedia, having similar composition to aqueous humor, is far superior physiological medium than the traditionally used PBS plus glucose to analyze the effect of the drugs to measure outflow facility. We hope that the newly developed real time perfusion system will be valuable for studies aimed at characterizing the molecular mechanism(s) for regulation of aqueous outflow in enucleated cadaver eyes.
This PDF is available to Subscribers Only