Purchase this article with an account.
Duck Jin Hwang, Se Joon Woo, Sang Yoon Lee, Jeeyun Ahn, Seong Joon Ahn, Kyu Hyung Park; Effect Of Diabetic Macular Edema On Peripapillary Retinal Nerve Fiber Layer Thickness Profiles. Invest. Ophthalmol. Vis. Sci. 2012;53(14):394.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Change in the retinal nerve fiber layer thickness (RNFL) thickness is one of the most important findings for the early diagnosis and determination of glaucoma progression. The aim of this study was to investigate the effect of macular edema (ME) on RNFL measurements using Optical Coherence Tomography (OCT) in patients with diabetic retinopathy.
Part 1: One hundred and fifty seven eyes of 107 patients (40 diabetic patients with ME and 67 diabetic patients without ME) were included in the study. Stratus OCT examination with macular thickness mapping and RNFL analysis protocol were performed. RNFL thickness was measured in 4 quadrants around the optic disc and the overall mean RNFL thickness was assessed. RNFL thickness was compared between ME group and non-ME group. In addition, the relationship between RNFL profiles and macular thickness was evaluated. Part 2: Twenty three eyes of 20 patients who received an intravitreal injection of 1.25mg of bevacizumab for diabetic macular edema were included. All eyes underwent Spectralis OCT before and after receiving a single injection of bevacizumab. Average and 4 quadrant peripapillary RNFL thickness profiles of pre- and post-injection were compared.
Part 1: There was a significant difference in RNFL profiles between ME group (82 eyes) and non-ME group (75 eyes). Global RNFL thickness was thicker in ME group (117.8±19.2 μm) than non-ME group (103.3±13.3 μm, p <0.001). RNFL thickness of all four quadrants was also thicker in ME group than that of non-ME group (p=<0.001). Global RNFL thickness was significantly correlated with mean foveal thickness (r=0.406, p<0.001). Part 2: In 23 eyes, there was a significant decrease of the foveal thickness (p <0.001) and RNFL thickness (p=0.001) after intravitreal bevacizumab injections. The mean RNFL thickness of pre- and post-injection was 126.1 ± 31.8 μm, 119.5 ± 33.2 μm, respectively (p =0.001). The reduction in RNFL thickness was largest in the temporal quadrant (12.4 μm), followed by superior (7.1 μm), nasal (3.7 μm), and inferior (3.5 μm) quandrants.
Overall, RNFL thickness was generally overestimated in diabetic patient with ME, thus implicating ME could mask the decreased RNFL thickness. Although clinical implications of these finding will require further studies, cautious evaluation of the RNFL thickness may be recommended in patient with glaucoma and diabetic macular edema.
This PDF is available to Subscribers Only