The movement of the common carotid artery (CCA) vessel wall has been well accepted as one important indicator of atherosclerosis, but it is still one challenge to estimate the motion of vessel wall from ultrasound images. In this paper, a robust H∞ filter was incorporated with block matching (BM) method to estimate the motion of carotid arterial wall. The performance of our method was compared ...

An algorithm for non-parametric estimation of one-dimensional ul-trasound pulses in echo sequences from human tissues is derived. The technique is a variation of the homomorphic ltering technique using the real cepstrum, and the underlying basis of the method is explained. The algorithm exploits a priori knowledge about the structure of rf line echo data and can employ a number of adjacent rf l...

Information on fetal weight is of importance to obstetricians in the management of pregnancy and delivery. The objective of this study is to compare the accuracy of clinical and sonographic methods of predicting fetal weights at term. This prospective comparative study of 200 parturients was conducted at the University of Calabar Teaching Hospital, Calabar. The study participants were mothers w...

Estimation of the tissue perfusion parameters using ultrasound contrast agent can help to improve diagnosis occlusion of coronary arteries thus it can helps to prevent myocardial infarction. Precise registration of ultrasound time sequence is precondition for automatic and reliable perfusion analysis. Many image registration methods were developed, but ultrasound image registration is a still a...

The major issue associated with ultrasound imaging is that it may be corrupted by speckle noise during image acquicition. Speckle pattern is a form of multiplicative noise which blurs the ultrasound images. It reduces the contrast and resolution of ultrasound images which results in poor interpretation of image features. Hence speckle reduction is often used as a preprocessing step for successf...

Time-delay estimation determines the relative displacement between two ultrasound echo signals. In this paper, we propose a new time-delay estimation algorithm which uses only the sign function to obtain the corresponding timedelay estimate. The performance of the proposed algorithm was compared with two established algorithms, i.e., normalized cross-correlation (NCC) and sum of squared differe...

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PURPOSE Ultrasound-based motion estimation is an expanding subfield of image-guided radiation therapy. Although ultrasound can detect tissue motion that is a fraction of a millimeter, its accuracy is variable. For controlling linear accelerator tracking and gating, ultrasound motion estimates must remain highly accurate throughout the imaging sequence. This study presents a temporal regularizat...

Background: Knowledge of the weight of the foetus in utero is important for the obstetricians to decide the time and mode of delivery. It can be estimated clinically, biochemically or by radiological imaging .None of the diagnostic tools are direct .Interestingly clinically estimated foetal weight is being found more precise than radiological estimation Aim:. This study was designed to find the...

A new estimator for determining the two-dimensional velocity vector using a pulsed ultrasound field is derived. The estimator uses a transversely modulated ultrasound field for probing the moving medium under investigation. A modified autocorrelation approach is used in the velocity estimation. The new estimator automatically compensates for the axial velocity when determining the transverse ve...