Purchase this article with an account.
J.A. Jamison, S. Ball, C. Miller, T.S. Kern, D.P. Bingaman; A Comparison of Oscillatory Potential Isolation Techniques and the Functional Protection of Topical 0.3% Nepafenac in the Streptozotocin Induced Model of Diabetes . Invest. Ophthalmol. Vis. Sci. 2006;47(13):1675.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Evaluate the effect of sharp vs. broad band cutoff filters used to isolate OP’s in STZ–induced diabetes, treated and untreated for 9 months with 0.3% topical Nepafenac.
Diabetic and control animals received 0.3% Nepafenac or mannitol vehicle 4x/day for 9 months. Cone ERG’s were collected over a 2 log range (max 0.52 log cd sec/m2) using a Ganzfeld LKC (UTAS) system after a 7 minute light adaptation of 0.8 log cd/m2. OP’s were isolated from the maximum intensity response using LKC internal software, as well raw data was imported into MatlabTM (Mathworks Inc.) and analyzed using sharp cutoff filters (SCF) with low cutoff between 25–100hz and high cutoff of 300Hz.
Stage 1a diabetic patients are characterized by normal amplitude OP’s with prolonged timing of the individual peaks, similar result were observed between control and diabetic animals. There was no statistical difference in RMS power between groups. There was a significant delay in the summed timing of OP’s 1–4 in the diabetic animals, which was prevented with 0.3% Nepafenac. These results were consistent with which ever analysis technique we used although the SCF’s provided smaller errors and a qualitatively better result when analyzing the amplitude and timing of individual OP’s. Considering only the first OP using the LKC program, the diabetic animals have both reduced amplitude and delayed timing. Nepafenac treated animals have similar timing but reduction in amplitude of OP 1 compared to control, whereas vehicle treated animals have amplitude similar to controls with a delay in timing. This dichotomy could result in a confusing interpretation of the data. Using a SCF’s resulted in both timing and amplitude matching of control and Nepafenac treated as well as diabetic and vehicle treated animals across all of the observed OP’s.
0.3% Nepafenac protected against OP timing delays in the STZ–induced diabetic rat model. Using SCF’s can better isolate OP’s and provide better resolution of detail than broader band filters.
This PDF is available to Subscribers Only