Ultrasound. Ultrasound (US) based imaging methodologies have been wildly adopted to study VC in dialysis patients to assess superficial vessels, such as the femoral and carotid arteries [319]. Ultrasound involves the transmission of high frequency sound waves (2 to 10 MHz) through an anatomic site of interest followed by conversion of echoes into electrical impulses, producing 2-dimensional images [320]. Ultrasound studies rely on the availability of the tool, the inexpensive nature of the measurements and the ease of identification of superficial vessels such as the carotid and femoral arteries. Ultrasound- based methods, however, only provide qualitative and semi-quantitative assessment of VC [321, 322]. The distinction between intimal and medial calcification is difficult and results are, for the most part, based on subjective interpretation [323]. However, the results generated with this methodology appear to be a reliable means for VC screening and outcome prediction. The advantages of US are that it is a safe method with no radiation exposure, and is relatively low cost, moreover, it permits assessment of calcification of superficial vessels such as carotid and femoral arteries [324]. It is however operator dependent and only a qualitative method [324].
Ultrasound. Muscle morphology was acquired through B-mode ultrasound images (model LOGIQ S7 Expert, General Electric, GE Healthcare, USA), on the dominant side of the participants, defined as the leg chosen to kick a ball (26). All images were acquired by an evaluator with 700 hours of experience in image acquisition and image processing was performed by an evaluator with 312 hours of experience in image analysis. The procedures for acquiring images for the cross-sectional area (CSA) were conducted as described by Xxxxxxx et al. (21). This technique for assessing CSA was validated by Xxxxxxxx et al (29) by comparing the extended field-of-view ultrasound method with computed tomography (ICC: 0.95 - 0.99). First, the greater trochanter and the lateral epicondyle of the femur were identified and the femur length was measured, then, starting from the proximal region of the thigh, points 40, 50, 60, and 70% of the femur length were identified. Thus, the participants' anterior thigh region was marked in each of these percentages for image acquisition. After 5 minutes of rest on a stretcher (5), two images were acquired in each of the percentages in the extended view mode with a 5 cm transducer. The settings used were: frequency of 10 MHz, image capture depth of 7 cm, and gain of 60 dB. Water-based gel was applied to the transducer head to achieve acoustic coupling, and extra care was taken to avoid muscle strain. Rectus femoris and vastus lateralis CSA were manually demarcated using ImageJ public domain software (V.1.52; National Institute of Health, USA). The average of the four percentages for each muscle represented the CSA for the statistical analysis. For muscle architecture, the same settings reported above were used. Then, the transducer was positioned longitudinally to the femur, oriented parallel to the muscle fascicles, and perpendicular to the skin (15). Two images were acquired at 50% of the femur length for the rectus femoris and vastus lateralis. Muscle thickness was determined as the distance between the muscle's deepest and most superficial aponeurosis (6). For the acquisition of muscle thickness, five measurements were taken along the image (one at each end, one central, and two intermediates), then the average between them was calculated. The fascicle length was estimated using the Fini and Komi equation (13) and understood as the length of the fascicular path between the superficial and deep aponeurosis. The pennation angle was defined as the angle betwee...
Ultrasound. On B-mode ultrasound fibroids appear as discrete, globular structures with well defined circumference (Figure 4). However they can have a variety of appearances depending on the ratio of connective tissue to smooth muscle and the presence and type of degeneration. Bizarre appearances can occur after fibroid degeneration when they can contain hypoechoic areas or Figure 4 Transvaginal ultrasound image showing a submucous fibroid with saline infusion to delineate the endometrial cavity. calcifications. High resolution transvaginal ultrasound can identify fibroids as small as 4 – 5mm which are commonly asymptomatic (Xxxxxx 1998). The high diagnostic value of 2D transvaginal ultrasound was confirmed by Xxxxxxx et al. in a study of 106 women scheduled for hysterectomy. The positive predictive value of ultrasound was 96% while ultrasound was accurate to within 2 mm of the true fibroid diameter as measured at histopathology (Dueholm et al. 2002). It should be noted that the performance of ultrasound deteriorated when the uterine volume was large secondary to the presence of several tumours. This may be due to increasing distance between the transvaginal probe and the fibroid under examination. Despite its high sensitivity 2D grey scale ultrasound performs poorly in distinguishing between intramural and submucous fibroids as it is not always easy to discern the relationship between fibroid and endometrial cavity. Xxxxxx et al. showed that 2D transvaginal ultrasound misclassified 36% of fibroids when compared to hysteroscopic findings. Enhancing the image with the infusion of saline improved performance of 2D ultrasound and misclassification dropped to 2.8% (Xxxxxx et al. 1993). The enhancing effect of saline infusion for the diagnostic ability of 2D ultrasound was confirmed by Xxxxxxxxx et al who compared ultrasonic findings to those at the time of surgery (Xxxxxxxxx et al. 1995). They reported 100% sensitivity and specificity for sonohysterography and less than 2 mm difference between sonohysterography and direct evaluation after surgery. Other groups have reported similar findings (Xxxxxxx et al. 2001) The high sensitivity of transvaginal ultrasound poses new problems for practitioners. Fibroids are often an incidental finding as tumours 5 mm in diameter do not cause symptoms. However they may become symptomatic if they grow to over 20 mm diameter (Wegienka et al. 2003). Given the dearth of information regarding the clinical course of these tumours with only two ...
Ultrasound. The sonographic differential diagnosis of a pelvic masses based on their location, internal consistency, size and definition of borders is presented. Besides separating pelvic masses into the conventional categories of cystic, solid, complex and grayscale sonographic features of a pelvic mass can be accustomed to subcategorize these masses into a more useful vary diagnoses. The information of sonographic can be effectively utilized for establishing differential diagnoses of pelvic masses. Many pelvic masses, for example, dermoid cysts diagnostic more than one sonographic appearance, therefore, had to be considered in more than one diagnostic category (Benacerraf al., 2015).
Ultrasound. Distributors who sell Ultrasound Products may not appoint Sub-Distributors for Ultrasound Products.
Ultrasound. Ultrasound is not useful in assessment of lesion size and should not be used as a method of measurement. If new lesions are identified by ultrasound in the course of the study, confirmation by CT is advised.
Ultrasound assisted ionic liquid extraction IL-based ultrasound-assisted extraction (IL-UAE) methods have been developed for the effective extraction of alkaloids (Xxx et al., 2009; Xxxxx et al., 2009) and phenolic compounds (Xxxxx et al., 2010) from plant material. The extraction time is one of the most important factors and optimal extraction efficiency can be achieved in 30-40 min. For example, the extraction efficiency of the optimized IL-UAE approach increased the yield of piperine by ca. 30- 45% as compared with UAE but with a conventional solvent (ethanol) (Xxx et al., 2009).
