Purchase this article with an account.
L. Nehmad, R.J. Madonna, B. Bathija, M. Halkias, A. Chandra; The Influence of Cataract Surgery on Macular Structure as Measured by OCT and Its Association With Visual Function . Invest. Ophthalmol. Vis. Sci. 2006;47(13):661.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Changes in macular structure are well known following cataract surgery, even in patients without clinical evidence of cystoid macular edema (CME). Optical coherence tomography (Stratus OCT, Carl Zeiss Ophthalmics, Inc., Dublin, CA) is a powerful, non–invasive tool that has been shown to be able to measure macular structure. The purpose of this study is to compare OCT macular strctural measurements before and after cataract surgery and to determine whether structural changes affect final visual function.
All patients about to undergo cataract surgery were eligible for the study. Patients with reduced visual function due to causes other than cataract, with clinically evident post–operative CME, and those with poor quality OCT images were excluded. Patients were tested pre–operatively, and then during a 90–day follow–up period. At each study visit, a fast macular thickness map was generated. From this map, foveal thickness, central 1mm average thickness, and total macular volume over 6mm were recorded. Additionally, best corrected Snellen visual acuity (VA) and contrast sensitivity (CS) were measured.
Eleven patients met entrance criteria. Average pre–operative measurements were 154.6 microns +/– 21.5 (range 126–200), 189.4 microns +/– 16.9 (range 168–215), and 6.28 cubic mm +/– 0.3 (range 5.88–6.88) for foveal thickness, central 1mm average thickness, and total macular volume respectively. Average measurements at the last post–operative visit were 174.1 microns +/– 25.6 (range 138–213), 204.9 microns +/– 21.5 (range 172–245), 6.69 cubic mm +/– 0.57 (range 5.82–7.96) for foveal thickness, central 1 mm average thickness and total macular volume, respectively. Correlation between the largest OCT–measured macular change at any post–operative visit and reduced final visual function was found for foveal thickness and VA, and CS at .5, 1, and 2 cycles/degree; total macular volume and VA, and CS at .5, 2, 4 and 6 cycles/degree; central average 1 mm thickness and VA, and CS at .5, 2 and 6 cycles per degree. However, only total macular volume and VA and CS at 6 cycles/degree reached a statistical significance level of p <.10. The greatest percentage increase in total macular volume at any post–operative visit was the best predictor of reduced, final visual function.
Comparison of OCT macular structural measurements before and after cataract extraction may serve to identify patients who exhibit reduced final visual function. Measurement of total macular volume may be the best predictor of final visual function.
This PDF is available to Subscribers Only