Analysis of normal human retinal vascular network architecture using multifractal geometry

• Published in: International journal of ophthalmology Vol. 10; no. 3; pp. 434 - 438
• Main Author: tefan ？？lu Sebastian Stach Dan Mihai C？lug？ru Carmen Alina Lupa？cu Simona Delia Nicoar
• Format: Journal Article
• Language: English
• Published: China International Journal of Ophthalmology Press 18.03.2017; Press of International Journal of Ophthalmology (IJO PRESS)
• Subjects: Clinical Research; generalized dimensions; multifractal; retinal image analysis; retinal microvasculature; retinal vessel segmentation; standard box-counting method; generalized dimensions; retinal vessel segmentation; standard box-counting method; multifractal; retinal image analysis; retinal microvasculature
• DOI: 10.18240/ijo.2017.03.17
• ISSN: 2222-3959

AIM：To apply the multifractal analysis method as a quantitative approach to a comprehensive description of the microvascular network architecture of the normal human retina.METHODS：Fifty volunteers were enrolled in this study in the Ophthalmological Clinic of Cluj-Napoca,Romania,between January 2012 and January 2014. A set of 100 segmented and skeletonised human retinal images,corresponding to normal states of the retina were studied. An automatic unsupervised method for retinal vessel segmentation was applied before multifractal analysis. The multifractal analysis of digital retinal images was made with computer algorithms,applying the standard boxcounting method. Statistical analyses were performed using the Graph Pad In Stat software.RESULTS：The architecture of normal human retinal microvascular network was able to be described using the multifractal geometry. The average of generalized dimensions（D_q）for q=0,1,2,the width of the multifractal spectrum（Δα=α_（max）-α_（min））and the spectrum arms＇ heights difference（│Δf│）of the normal images were expressed as mean±standard deviation（SD）：for segmented versions,D_0=1.7014±0.0057; D_1=1.6507±0.0058; D_2=1.5772±0.0059; Δα=0.92441±0.0085; │Δf│= 0.1453±0.0051; for skeletonised versions,D_0=1.6303±0.0051; D_1=1.6012±0.0059; D_2=1.5531± 0.0058; Δα=0.65032±0.0162; │Δf│= 0.0238±0.0161. The average of generalized dimensions（D_q）for q=0,1,2,the width of the multifractal spectrum（Δα）and the spectrum arms＇ heights difference（│Δf│）of the segmented versions was slightly greater than the skeletonised versions.CONCLUSION：The multifractal analysis of fundus photographs may be used as a quantitative parameter for the evaluation of the complex three-dimensional structure of the retinal microvasculature as a potential marker for early detection of topological changes associated with retinal diseases.