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Proposes a real-time retinal tracking system for image-guided laser treatment. Strategy for retinal image segmentation; Detection of blood vessel boundaries using deformable models; Segmentation of the optic disc; Estimation of laser shot locations.

Presents an approach for speckle reduction and coherence enhancement of ultrasound images based on nonlinear coherent diffusion. Pattern of medical ultrasound speckle; Effect of logarithmic compression on clinical images; Application of diffusion filtering models.

We develop a simple yet effective technique for motion artifact suppression in ultrasound images reconstructed from multiple acquisitions. Assuming a rigid-body motion model, a navigator echo is computed for each acquisition and then registered to estimate the motion in between acquisitions. By detecting this motion, it is possible to compensate for it in the reconstruction step to obtain images that are free of lateral motion artifacts. The theory and practical implementation details are described and the performance is analyzed using computer simulations as well as real data. The results indicate the potential of the new method for real-time implementation in lower cost ultrasound imaging systems. [ABSTRACT FROM AUTHOR]

Presents a study of the nonlinear dynamics of electrocardiogram (ECG) signals for the characterization of arrhythmia. Facts on the use of Lyapunov exponents in the study; Classes of ECG signals; Analysis of parameters for the ECG model.

[Display omitted] • Hyperspectral imaging (HSI) system can be utilized to distinguish spectral differences in biological soft tissues (kidney, heart, and liver). • The optical system comprises of two techniques to quantify the tissue's light transmission (T r) and diffuse light reflectance (R d), respectively. • The ANOVA test and Tukey's test were employed to categorize the tissue samples into three independent clusters (group I / group II / group III). • The investigation provides the optimum wavelength for each tissue based on their spectroscopic optical properties in the VIS-NIR spectrum. • The HSI system has potential applications in endoscopic interventions or open surgery in the diagnosis and therapy. The rapid advancement of diagnostic and therapeutic optical techniques for oncology demands a good understanding of the optical properties of biological tissues. This study explores the capabilities of hyperspectral (HS) cameras as a non-invasive and non-contact optical imaging system to distinguish and highlight spectral differences in biological soft tissues of three structures (kidney, heart, and liver) for use in endoscopic intervention or open surgery. The study presents an optical system consisting of two individual setups, the transmission setup, and the reflection setup, both incorporating an HS camera with a polychromatic light source within the range of 380 to 1050 nm to measure tissue's light transmission (T r) and diffuse light reflectance (R d), respectively. The optical system was calibrated with a customized liquid optical phantom, then 30 samples from various organs were investigated for tissue characterization by measuring both T r and R d at the visible and near infrared (VIS-NIR) band. We exploited the ANOVA test, subsequently by a Tukey's test on the created three independent clusters (kidney vs. heart: group I / kidney vs. liver: group II / heart vs. liver: group III) to identify the optimum wavelength for each tissue regarding their spectroscopic optical properties in the VIS-NIR spectrum. The optimum spectral span for the determined light T r of the three groups was 640 ∼ 680 nm, and the ideal range was 720 ∼ 760 nm for the measured light R d for mutual group I and group II. However, the group III range was different at a range of 520 ∼ 560 nm. Therefore, the investigation provides vital information concerning the optimum spectral scale for the computed light T r and R d of the investigated biological tissues (kidney, liver, and heart) to be employed in diagnostic and therapeutic medical applications. [ABSTRACT FROM AUTHOR]