Automatic retinal vessel tortuosity measurement

Retinal vessel tortuosity measurement is the reliable method used as an opthalmological diagnostic tool. For example, Retinopathy of Prematurity (ROP), this disease can be characterised by the increasing in vascular dilation and tortuosity. This paper proposes a method of how to measure and define tortuous scale using the mean curvature. The tortuosity measurement is calculated base on the radius derive from chord in each curve of the blood vessel. The result obtains from this method can set the standard of tortuosity grading in the retinal vessel. The advantage of this method is to reduce the error in tortuosity calculation, which cause by the low quality image of the retinal vessel.