TELKOMNIKA, Vol.17, No.1, February 2019, pp.463~472
ISSN: 1693-6930, accredited First Grade by Kemenristekdikti, Decree No: 21/E/KPT/2018
DOI: 10.12928/TELKOMNIKA.v17i1.11604 463
Received June 10, 2018; Revised November 9, 2018; Accepted December 7, 2018
Classification of neovascularization using
convolutional neural network model
Wahyudi Setiawan
1
, Moh. Imam Utoyo
2
, Riries Rulaningtyas
*3
1
Informatics Department, University of Trunojoyo Madura, Bangkalan, Indonesia
1,2
Mathematics Department, University of Airlangga, Surabaya, Indonesia
3
Physics Department, University of Airlangga, Surabaya, Indonesia
*Corresponding author, e-mail: riries-r@fst.unair.ac.id
Abstract
Neovascularization is a new vessel in the retina beside the artery-venous. Neovascularization can
appear on the optic disk and the entire surface of the retina. The retina categorized in Proliferative Diabetic
Retinopathy (PDR) if it has neovascularization. PDR is a severe Diabetic Retinopathy (DR). An image
classification system between normal and neovascularization is here presented. The classification using
Convolutional Neural Network (CNN) model and classification method such as Support Vector Machine,
k-Nearest Neighbor, Naïve Bayes classifier, Discriminant Analysis, and Decision Tree. By far, there are no
data patches of neovascularization for the process of classification. Data consist of normal, New Vessel on
the Disc (NVD) and New Vessel Elsewhere (NVE). Images are taken from 2 databases, MESSIDOR and
Retina Image Bank. The patches are made from a manual crop on the image that has been marked by
experts as neovascularization. The dataset consists of 100 data patches. The test results using three
scenarios obtained a classification accuracy of 90%-100% with linear loss cross validation 0%-26.67%.
The test performs using a single Graphical Processing Unit (GPU).
Keywords: classification, convolutional neural network, deep learning, diabetic retinopathy,
neovascularization.
Copyright © 2019 Universitas Ahmad Dahlan. All rights reserved.
1. Introduction
Fundus image is a retinal image obtained from the fundus camera. An expert analyzes
the fundus image to determine retina diseases. Diabetic Retinopathy (DR) is one of the retinal
diseases. Usually, DR is present on Diabetes Mellitus (DM) patient for more than 15 years. DR
causes blindness if not treated early [1].
A study in the UK, from 2004 to 2014, reported the number of people with DR. The
study used a sample of 7,707,475 DM patients. The results showed a percentage of DR
sufferers increases every year. In 2004, the number of patients with DR 0.9%, in 2014
increased to 2.3% of the DM patients [2]. Other studies, the people with DR in Southeast Asia,
reported 35% of patients with DM [3].
Clinical examination of DR is done through several tests include biomicroscope,
fluorescein angiography, fundus photo, and indocyanine green angiography. Also, experts
perform Optical Coherence Tomography (OCT). The results of the analysis should be supported
by age-related information, medical history, visual acuity, cardiovascular and disease
progression [4, 5]. The examination procedures consist of several tests. It needs a relatively
long time and expensive cost. An alternative solution is DR computationally detection.
The degree of abnormality DR is Non-Proliferative Diabetic Retinopathy (NPDR) and
Proliferative Diabetic Retinopathy (PDR). This article has focused on PDR classification. The
symptoms of PDR are new blood vessels on the surface of the retina or new blood vessels in
the Optic Disk. Figure 1 shows PDR fundus images.
There is widely research on PDR. Jelinek et al. have classified NPDR and PDR [6].
Goatman et al. have classified two classes, normal and abnormal [7]. Akram et al. have
classified three classes, normal, NVD, and NVE [8]. Welikala et al. have classified two classes,
PDR and NPDR [9]. Gupta et al. have classified three classes, NVE, NPDR and Normal [10].
The study performs image processing with conventional method phases. It includes
preprocessing, segmentation, feature extraction, feature selection, and classification. The