Detection and Analysis of Hard Exudates by Polarization-Sensitive Optical Coherence Tomography in Patients With Diabetic Maculopathy

作者：Lammer Jan^*; Bolz Matthias; Baumann Bernhard; Pircher Michael; Gerendas Bianca; Schlanitz Ferdinand; Hitzenberger Christoph K; Schmidt Erfurth Ursula

来源：Investigative Ophthalmology & Visual Science, 2014, 55(3): 1564-1571.

DOI：10.1167/iovs.13-13539

• hard exudates
• diabetic retinopathy
• polarization-sensitive OCT
• diabetic maculopathy
• color fundus photography

PURPOSE. To image and analyze hard exudates (HEs) and their precursors in patients with diabetic macular edema (DME) by using polarization-sensitive optical coherence tomography (PS-OCT).
METHODS. Twenty-two eyes of 16 patients with DME were imaged by using color fundus photography (CF) and PS-OCT. In PS-OCT, HEs were automatically detected by their distinct polarization-scrambling qualities. Color fundus images were manually graded for the presence of HEs by two masked graders and correlated with the corresponding PS-OCT HE maps: corresponding images were overlaid and an identical grid of 128 x 128 fields was used for correlation of detected HEs.
RESULTS. In all eyes, HEs were present owing to DME. Agreement of a pixel-to-pixel analysis of HEs in CF images was 0.72 (Cohen's kappa) between graders and 0.44 between graders and automated detection by PS-OCT. Mean +/- SD detection of HEs was significantly higher in PS-OCT than in manual grading (1180.5 +/- 1009.8 fields versus 828.8 +/- 695.0 fields; P = 0.02). The higher detection rate of PS-OCT was confirmed by a linear regression analysis with a slope of beta = 1.18 (r = 0.81).
CONCLUSIONS. PS-OCT enables not only two-dimensional imaging of the extent of HEs, as in CF, but also allows tissue-specific, three-dimensional imaging of HEs throughout retinal layers, based on their distinct polarization-scrambling characteristics. The higher detection rate in PS-OCT images indicates an increased sensitivity of PS-OCT imaging over conventional CF.

• 出版日期2014-3