Browsing by Author "Fox M.D."

Now showing 1 - 2 of 2

Hexagonal filters for ultrasound images
(2014) Contreras Ortiz, Sonia Helena; Fox M.D.
Most of the devices for acquisition and display of medical images use rectangular lattices even though there are other sampling strategies that can be more efficient in terms of resolution. This paper proposes an approach for ultrasound image enhancement that uses a hexagonal sampling scheme to display and process the images. The images were resampled on an interlaced grid. Interlaced sampling uses square pixels shifted half a pixel on alternate rows. Two types of hexagonal filters were designed and tested on ultrasound images: a statistical adaptive filter and an anisotropic diffusion filter. Results show improvements in signal-to-noise ratio and more natural representation of curved structures. © 2014 SPIE and IS&T.
Ultrasound image enhancement: A review
(2012) Contreras Ortiz, Sonia Helena; Chiu T.; Fox M.D.
Medical ultrasound imaging uses pulsed acoustic waves that are transmitted and received by a hand-held transducer. This is a mature technology that it is widely used around the world. Among its advantages are that it is cost-effective, flexible, and does not require ionizing radiation. However, the image quality is affected by degradation of ultrasound signals when propagating through biological tissues. Many efforts have been done in the last three decades to improve the quality of the images. This paper reviews some of the most important methods for ultrasound enhancement. We classified these techniques into two groups: preprocessing and post-processing, analyzed their benefits and limitations, and presented our beliefs about where ultrasound research could be directed to, in order to improve its effectiveness and broaden its applications. © 2011 Elsevier Ltd.