title: A study on hemorrhage detection using hybrid method in fundus images.
abstract: Image processing of a fundus image is performed for the early detection of diabetic retinopathy. Recently, several studies have proposed that the use of a morphological filter may help extract hemorrhages from the fundus image; however, extraction of hemorrhages using template matching with templates of various shapes has not been reported. In our study, we applied hue saturation value brightness correction and contrast-limited adaptive histogram equalization to fundus images. Then, using template matching with normalized cross-correlation, the candidate hemorrhages were extracted. Region growing thereafter reconstructed the shape of the hemorrhages which enabled us to calculate the size of the hemorrhages. To reduce the number of false positives, compactness and the ratio of bounding boxes were used. We also used the 5 × 5 kernel value of the hemorrhage and a foveal filter as other methods of false positive reduction in our study. In addition, we analyzed the cause of false positive (FP) and false negative in the detection of retinal hemorrhage. Combining template matching in various ways, our program achieved a sensitivity of 85% at 4.0 FPs per image. The result of our research may help the clinician in the diagnosis of diabetic retinopathy and might be a useful tool for early detection of diabetic retinopathy progression especially in the telemedicine.
authors.affiliation: Biomedical Engineering Branch, Division of Basic & Applied Sciences, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do, South Korea.
authors.forename: Jang Pyo
authors.initials: JP
authors.lastname: Bae
authors.forename: Kwang Gi
authors.initials: KG
authors.lastname: Kim
authors.forename: Ho Chul
authors.initials: HC
authors.lastname: Kang
authors.forename: Chang Bu
authors.initials: CB
authors.lastname: Jeong
authors.forename: Kyu Hyung
authors.initials: KH
authors.lastname: Park
authors.forename: Jeong-Min
authors.initials: JM
authors.lastname: Hwang
mesh_terms: D003930:Diabetic Retinopathy / Q000150:complications*; D005654:Fundus Oculi; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods; D012372:ROC Curve; D015203:Reproducibility of Results; D012166:Retinal Hemorrhage / Q000175:diagnosis* / Q000209:etiology; D042262:Retinoscopy / Q000379:methods*; D012680:Sensitivity and Specificity