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Abstract: An experimental study of the spatial resolution in elastography was conducted. Models that involved two cylindrical inclusions arranged as a wedge were used to characterize the axial and lateral resolution of the axial strain elastograms. A study of the dependence of the spatial resolution on several factors such as the algorithmic parameters, the applied strain and the modulus contrast was performed. The axial resolution was found to show a linear dependence with respect to the algorithmic parameters, namely the window length and the window shift used for strain estimation. The lateral resolution showed a weak dependence on the algorithmic parameters. A weak dependence of the spatial resolution on factors such as the modulus contrast and the applied strain was found. The trade-offs between the spatial resolution and the elastographic contrast-to-noise ratio (CNRe) were then analyzed. A nonlinear trade-off between the CNRe and the axial and lateral resolution was shown for conventional strain estimation techniques, with the CNRe improving at a more than linear rate with respect to a linear degradation in the resolution. This study provided an experimental framework for characterizing the spatial resolution in elastography and facilitating a comparison of the CNRe with spatial resolution. [Copyright &y& Elsevier]

Elastography involves tracking the ultrasonic A-mode signals before and after mechanical compression of tissue to form a computed image of the local strains undergone by various tissue components. The quality of the strain estimates in elastography is typically quantified using factors such as the elastographic SNR (SNRe), contrast-to-noise ratio (CNRe), and the spatial resolution. These quality factors depend on the mechanical parameters (such as the applied strain and the boundary conditions), the acoustic parameters (such as the sonographic SNR, the center frequency, and the bandwidth), and the signal-processing parameters (such as the window length and the window separation). Theoretical developments in elastography have established functional relationships between the SNRe and CNRe and these parameters. Similarly, simulations have established empirical relationships between the axial resolution and the acoustic and signal-processing parameters. We find that a trade-off exists between the achievable SNRe (CNRe) and the axial resolution in elastography and that the trade-off occurs only with respect to the signal-processing parameters. Theoretical work on the spatial resolution accompanied with simulations and experiments were used to confirm such an observation. The trade-off between the SNRe (CNRe) and the resolution was found to be nonlinear, with large improvements in the SNRe being possible at the expense of small reductions in the axial resolution. All the quality factors improve with the acoustic parameters, which suggests the preferred use of transducers with high absolute bandwidths and center frequencies. (E-mail: Jonathan.Ophir@uth.tmc.edu) [Copyright &y& Elsevier]

Objective To assess the results of our experience in correcting primary varicocele using a modified technique of antegrade scrotal sclerotherapy. Patients and methods From December 1997 to February 2000, 201 patients with primary varicocele underwent antegrade scrotal sclerotherapy. Before treatment all patients were evaluated by a physical examination, colour Doppler ultrasonography of the spermatic cord, and abdominal and scrotal ultrasonography. Sperm samples were analysed only in patients aged > 18 years. The treatment was administered using a special venous catheter system with a Y-adapter. Complications after treatment and the rate of persistence of reflux were assessed 3 and 6 months after the antegrade scrotal treatment, by clinical examination and colour-Doppler ultrasonography of the spermatic cord. Results The mean operative duration was 15 min; there were no significant complications during treatment and all patients were discharged within 4 h. Complications after treatment occurred in 10 of the 201 patients (5%); four patients had epididymo-orchitis, three a scrotal haematoma, one a surgical wound infection, one persistent scrotal pain and one persistent flank pain on the same side as the surgery. Reflux was persistent in 12 patients (6%). Conclusions Antegrade scrotal sclerotherapy is a simple, minimally invasive and highly effective technique for blocking spermatic vein reflux, with a low rate of complications. The technical changes simplified the cannulation of the spermatic vein and facilitated antegrade phlebography and sclerotherapy using the air-block technique. [ABSTRACT FROM AUTHOR]

Abstracrt ITER is incorporating two types of In-Vessel Coils (IVCs): ELM Coils to mitigate Edge Localized Modes and VS Coils to provide a reliable Vertical Stabilization of the plasma. Strong coupling with the plasma is required in order that the ELM and VS Coils can meet their performance requirements. Accordingly, the IVCs are mounted on the Vacuum Vessel (VV) inner wall, in close proximity to the plasma, just behind the Blanket Shield Modules (BSM). Due to high radiation environment, mineral insulated copper conductors enclosed in a stainless steel jacket have been selected. The reference design and prototype work provided a good basis for the development of radiation resistant conductor capable of operating within the harsh conditions in ITER vacuum chamber. However, this effort identified shortcomings in achieving satisfactory manufacturing solution, and most significantly, difficulties in brazing the brackets onto the ELM coil conductor. Since this process has not proven successful, alternative designs are under development and prototyping. Prototype manufacturing on the alternative designs has been completed at ICAS, Italy and ASIPP, China. The aim was to eliminate the need for internal coil joints, to prove the principle of longer conductor length manufacturing, and to perform bending and welding trials on two different conductor cross-sections: circular and square. The procurement of the IVCs and their conductors will be done via direct call for tender from the ITER Organization. This paper will give an overview of the alternative design and prototype manufacturing of the ITER In-Vessel coils. [ABSTRACT FROM AUTHOR]

The authors report a rare case of high flow priapism due to a bilateral arteriosinusoidal fistula conservatively treated. Twenty months after the treatment the patient claimed to have a normal sexual activity. [ABSTRACT FROM AUTHOR]