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This paper aims to review the mechanical characteristics of the robotic mechanisms developed for ultrasound examinations. This will help to extract those mechanical features which together can produce a design with superior functionality.

Following an introduction regarding ultrasound examination, this paper discusses the concept of robotic ultrasound imaging and classifies the mechanisms in terms of their power trains used for robotic and haptic devices which assist physicians to perform ultrasound imaging on patients. A set of mechanical characteristics which together can generate a superior design is also presented.

The present paper shows that the robotic devices developed so far can perform ultrasound examinations. Each design with its own advantageous characteristics, and their simultaneous implementation in a new design, will create a robotic device with improved performance.

This paper provides a detailed review of the developments of the robotic systems for ultrasound examinations and some guidelines for new designs with improved functionality.

Twin to Twin Transfusion Syndrome (TTTS) is a well understood, yet under-recognized, placental disease affecting any given pregnancy at a rate of 1 in 1,000. There is no clustering of TTTS; instead the threat remains pathologically distinctive due to its pervasiveness. However, while incidence rates are random, survival rates are not. Despite compliant acceptance of “routine prenatal care,” sadly, there are many women who for currently unknown reasons are not receiving the advanced prenatal care needed to appropriately screen for, diagnosis and treat TTTS. And these women are paying the ultimate price for such obstetrical oversight.

This study hypothesizes that differential care being given by primary obstetricians of TTTS patients is resulting in experienced inequalities. Utilizing social reproduction theory, and through ethnographic and quantitative analyses of primary data, this study seeks to divulge the complex social processes taking place (or failing to take place) within the world of American obstetrics, and begin to understand how they are affecting TTTS mortality and morbidity rates.

Findings illuminate a profound imbalance of power and influence amongst the following entities: American Congress of Obstetricians and Gynecologists and Society of Maternal Fetal Medicine; obstetrical training and practice; and levels of patient awareness and advocacy.

This study argues that the current social relations being reproduced by these entities are perpetuating a climate that allows for disregard of proper TTTS management. Specifically, this study theoretically explores what social relations and subsequent (in)actions are being reproduced prior to TTTS diagnoses, and applies the effects of those observations.

Today, medical models can be made by the use of medical imaging systems through modern image processing methods and rapid prototyping (RP) technology. In ultrasound imaging systems, as images are not layered and are of lower quality as compared to those of computerized tomography (CT) and magnetic resonance imaging (MRI), the process for making physical models requires a series of intermediate processes and it is a challenge to fabricate a model using ultrasound images due to the inherent limitations of the ultrasound imaging process. The purpose of this paper is to make high quality, physical models from medical ultrasound images by combining modern image processing methods and RP technology.

A novel and effective semi‐automatic method was developed to improve the quality of 2D image segmentation process. In this new method, a partial histogram of 2D images was used and ideal boundaries were obtained. A 3D model was achieved using the exact boundaries and then the 3D model was converted into the stereolithography (STL) format, suitable for RP fabrication. As a case study, the foetus was chosen for this application since ultrasonic imaging is commonly used for foetus imaging so as not to harm the baby. Finally, the 3D Printing (3DP) and PolyJet processes, two types of RP technique, were used to fabricate the 3D physical models.

The physical models made in this way proved to have sufficient quality and shortened the process time considerably.

It is still a challenge to fabricate an exact physical model using ultrasound images. Current commercial histogram‐based segmentation method is time‐consuming and results in a less than optimum 3D model quality. In this research work, a novel and effective semi‐automatic method was developed to select the threshold optimum value easily.

Hospital waiting lists are a feature of publicly funded health services that result when demand appears to exceed supply. While much has been written about surgical waiting lists, little is known about the dynamics of radiology waiting lists, which is surprising given that rational treatment, and indeed the medical profession's claim to expertise, rests on establishing a diagnosis. This paper reports the findings of a case study of a problematic ultrasound waiting list. In particular, this paper highlights how the management of the ultrasound waiting list served to subordinate the needs of waiting patients and their general practitioners to the interests and values of radiologists. Radiologist concern to protect specialist expertise from encroachment by outpatient clinicians and sonographers is implicated in the growth of the ultrasound waiting list. It is argued that an adequate understanding of ultrasound waiting lists depends on grasping how radiologists are successful in structuring problems of access in ways that enhance radiologist control over ultrasound imaging. The case study reported helps to shed light on why increasing funding to clear waiting lists proves ineffective.

The present work aims to deal with ultrasound-assisted organic pigment (phthalocyanine blue and green) dispersion and its comparison with the conventional approach.

Ultrasound is expected to give beneficial results based on the strong shear forces generated by cavitational effects. The dispersion quality for preparation using an ultrasound-based method has been compared with dispersion obtained using high-speed dispersion mill. Effects of different operating parameters such as probe diameter and use of surfactants on the physical properties of dispersion and the colour strength have been investigated. Calculations for the energy requirement for two approaches have also been presented.

The use of sodium dodecyl sulphate and Tween 80 surfactants shows better performance in terms of the colour properties of dispersion prepared in water and organic solvent, respectively. Ultrasound gives better dispersion quality as compared to the conventional approach.

The present work presents a new approach of ultrasound-assisted dispersion of phthalocyanine blue and green pigments. Understanding into the effect of surfactants and type of solvent also presents new important design-related information.

Previous studies have proven that, under optimised ultrasonic conditions, a range of materials used in electronic manufacturing can be sonochemically surface modified using benign solutions at low temperature. The purpose of this paper is to focus on a specific process, namely, the desmearing of through holes in printed circuit boards (PCB). The objective was to determine whether the introduction of low frequency ultrasound (20 kHz) to the “etch” stage of a standard “swell and etch” desmear system could enable reduced temperature processing and the use of less chemistry in the permanganate solution.

The study was divided into three main stages. In the first “screening” phase, the effect of ultrasound in the etch solution was studied by measuring the weight loss after desmear on a PCB laminate material (Isola 370HR). Factors such as etch temperature and concentration of permanganate (including permanganate‐free) were varied. In stage 2, confirmatory runs were carried out on the most promising conditions from the screening work and through holes in a four‐layer multi‐layer board (MLB) were assessed for smear removal using a scanning electron microscope (SEM). Finally, a four‐layer MLB was desmeared through the most promising ultrasonic process and then metallized at a PCB manufacturer. Thermal shock testing was subsequently carried out and sections from the board assessed for inter‐connection defects (ICDs).

The initial screening study indicated that, whenever ultrasound was used in the etch stage of the desmear process, significantly higher weight loss was achieved compared to a standard “silent” process. This effect was most pronounced when permanganate was removed from the etch solution and, in this situation, weight loss could be an order of magnitude higher than the silent equivalent. Further testing on through holes suggested that smear‐free inner‐layers could only be guaranteed if permanganate was present in the etch solution but that ultrasound again improved smear removal. Final testing under semi‐production conditions confirmed that, if ultrasound was employed in the etch part of the desmear process, then a reduction in processing temperature from 85°C to 60°C could be achieved and the permanganate concentration halved (65 to 33 g/L) whilst still achieving ICD‐free boards.

The paper indicates the feasibility of using ultrasound to reduce temperatures and chemical concentrations used in the permanganate etch solution, whilst still producing through holes with no ICDs.

Ultrasound is a well-established technology in medical science, though many of the conventional measurement systems (hydrophones and radiation force balances [RFBs]) often lack accuracy and tend to be expensive. This is a significant problem where sensors must be considered to be “disposable” because they inevitably come into contact with biological fluids and expense increases dramatically in cases where a large number of sensors in array form are required. This is inevitably the case where ultrasound is to be used for the in vitro growth stimulation of a large plurality of biological samples in tissue engineering. Traditionally only a single excitation frequency is used (typically 1.5 MHz), but future research demands a larger choice of wavelengths for which a single broadband measurement transducer is desirable. Furthermore, because of implementation conditions there can also be large discrepancies between measurements. The purpose of this paper deals with a very cost-effective alternative to expensive RFBs and hydrophones.

Utilization of cost-effective piezoelectric elements as broadband sensors.

Very effective results with equivalent (if not better) accuracy than expensive alternatives.

This paper concentrates on how very cost-effective piezoelectric ultrasound transducers can be implemented as sensors for ultrasound power measurements with accuracy as good, if not better than those achievable using radiation force balances or hydrophones.

Describes a prospective study to establish the clinical outcome of patients who had undergone Doppler ultrasound for symptomatic suspected deep vein thrombosis, focusing on 142 consecutive patients referred for ultrasound investigation of their leg symptoms. Outcome measures included presence or absence of thrombus on ultrasound; re‐admission or outpatient investigations post ultrasound; and mortality at one year. Concludes that no patient with a negative Doppler ultrasound examination subsequently developed a thrombus in the following year although 18.8 per cent had died. Suggests that patients with leg symptoms of venous thrombosis but negative ultrasound should be followed up closely because of the likelihood of underlying pathology.

The purpose of this study is to develop a hybrid algorithm for segmenting tumor from ultrasound images of the liver.

After collecting the ultrasound images, contrast-limited adaptive histogram equalization approach (CLAHE) is applied as preprocessing, in order to enhance the visual quality of the images that helps in better segmentation. Then, adaptively regularized kernel-based fuzzy C means (ARKFCM) is used to segment tumor from the enhanced image along with local ternary pattern combined with selective level set approaches.

The proposed segmentation algorithm precisely segments the tumor portions from the enhanced images with lower computation cost. The proposed segmentation algorithm is compared with the existing algorithms and ground truth values in terms of Jaccard coefficient, dice coefficient, precision, Matthews correlation coefficient, f-score and accuracy. The experimental analysis shows that the proposed algorithm achieved 99.18% of accuracy and 92.17% of f-score value, which is better than the existing algorithms.

From the experimental analysis, the proposed ARKFCM with enhanced level set algorithm obtained better performance in ultrasound liver tumor segmentation related to graph-based algorithm. However, the proposed algorithm showed 3.11% improvement in dice coefficient compared to graph-based algorithm.

The image preprocessing is carried out using CLAHE algorithm. The preprocessed image is segmented by employing selective level set model and Local Ternary Pattern in ARKFCM algorithm. In this research, the proposed algorithm has advantages such as independence of clustering parameters, robustness in preserving the image details and optimal in finding the threshold value that effectively reduces the computational cost.

Ultrasound examinations represent one of the major diagnostic modalities of future healthcare. They are currently used to support medical space research but require a high skilled operator for both probe positioning on the patient's skin and image interpretation. TERESA is a tele‐echography project that proposes a solution to bring astronauts and remotely located patients on ground quality ultrasound examinations despite the lack of a specialist at the location of the wanted medical act.