Cerebral vessel enhancement using bilateral and Hessian-based filter

Vessel enhancement in magnetic resonance angiography (MRA) is an important preprocessing step for stroke surgical planning and further processing. Bilateral filter has been widely used to reduce noise due to its ability for smoothing an image and preserve the edges. It suffers a drawback of over smoothing that leads to discontinuity of blood vessels when applied to MRA image. Hessian-based filter is known to have the ability of enhancing the vessels and preserving the geometrical structure. This paper presents the vessel enhancement technique which combines bilateral and Hessian-based filters to exploit the advantages of them. The bilateral filtered images show that weighted bilateral filter can reduce more noise when comparing the peak signal-to-noise ratio (PSNR) value. Then, Hessian-based filter is performed on several types of preprocessed images to compare the performance of this technique on different types of images. Our method shows a promising result in suppressing the noise that is enhanced by Hessian-based filter.