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High-frequency Ultrasound (high-frequency + ultrasound)
Selected AbstractsImaging of the Calf Vocal Fold With High-Frequency Ultrasound,THE LARYNGOSCOPE, Issue 10 2008Conor J. Walsh MSME Abstract Objectives/Hypothesis: High-frequency ultrasound imaging offers the potential for assisting in the diagnosis and treatment of vocal fold pathology if it allows aspects of vocal fold microstructure to be visualized noninvasively. The objective of this study was to assess the ability of high-frequency ultrasound to image vocal fold anatomy and injected biomaterials. Study Design: The vocal folds of two excised calf larynges were imaged ex vivo and compared with corresponding histological sections. Methods: High-frequency ultrasound imaging was performed under saline submersion using 40 and 50 MHz transducers, and corresponding cryostat cross-sections were stained with H&E, Trichome, and Verhoeff's Van Gieson stains. Results: The epithelial surface, lamina propria, and underlying muscle were easily identified with the high-frequency ultrasound as verified with histological sections representing each imaged region. The arytenoid cartilage vocal process can also be clearly distinguished from the surrounding tissue, as can the full extent of injected biomaterials within the superficial lamina propria. Useful ultrasound resolution was obtained to depths of at least 10 mm within the tissue with the 40 MHz transducer. Conclusions: This preliminary study demonstrates the capability of high-frequency ultrasound to image the layered anatomy of the calf vocal fold and to discern materials injected into the superficial lamina propria, indicating that this technology holds a strong potential for use in phonosurgery. [source] Medical imaging and MRI in nail disorders: report of 119 cases and review of the literatureDERMATOLOGIC THERAPY, Issue 2 2002Bertrand Richert Radiographs remain the golden standard for exploration of the bony structures located beneath the nail plate, but they provide no information on the perionychium. Until a few years ago the nail apparatus was deprived of investigative medical imaging. Glomus tumor was the only condition that was explored using invasive techniques such as angiography or scintigraphy. High-frequency ultrasound rapidly came up against technical limits. High-resolution magnetic resonance imaging (MRI) offers a superior alternative in detection of distal lesions as well as their relationship with the adjacent structures. MRI provides an accurate analysis of the nail apparatus with detection of lesions as small as 1 mm. This noninvasive technique will allow us to better understand, diagnose, and treat pathologies of the distal phalanx. [source] Salivary simulation with ascorbic acid enhances sonographic diagnosis of obstructive sialadenitisJOURNAL OF CLINICAL ULTRASOUND, Issue 6 2009Alessandro Bozzato MD Abstract Purpose. High-frequency ultrasound (US) is routinely used to evaluate various diseases of the salivary glands. Normally, the duct network of the submandibular and parotid glands is not visible during US assessment. In obstructive sialadenitis of the parotid and submandibular glands, localization of the obstacle is often difficult. Methods. In a case-control study, the sonographic visibility of the duct before and after stimulation with oral ascorbic acid (vitamin C) was compared with sialendoscopy as the gold standard. Twenty male and 23 female patients suffering from salivary gland diseases were included in this study and compared with 25 healthy volunteers. US examination of the parotid and submandibular glands was performed before and after oral ascorbic acid stimulation. Changes in visibility of the main excretory duct were recorded and US diagnoses were compared with results of sialendoscopy. Results. In 7 of 25 controls, the main duct became partially visible after stimulation. In the group of 43 patients, the main duct was depicted before stimulation in 27 patients (63%). After ascorbic acid stimulation, the main duct became visible in 41 patients (95%). Grading the stimulated duct dilation by measuring diameters at different points revealed no correlation with the underlying type of pathology. Conclusions. Application of ascorbic acid prior to diagnostic US examination facilitates the sonographic evaluation of obstructive salivary gland diseases. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2009 [source] Ultrasound detection of spontaneous hepato-cellular carcinomas in X/myc bitransgenic miceLIVER INTERNATIONAL, Issue 6 2004W. Mai Abstract: Aims: To evaluate trans-abdominal ultrasound for the detection of Hepatocellular carcinoma (HCC) in a bitrasgenic murine (X/myc) model using a commercially available high-frequency ultrasound unit. Methods: Sixty-one female animals were included in this study. These animals were submitted to a single ultrasound examination of the liver under general anesthesia (isoflurane), and then euthanized. Results of ultrasound were compared with necropsy and histopathology. Results: The lesions demonstrated a fairly consistent aspect (oval- or round-shaped, well-defined hypoechoic homogeneous lesions), and lesions as small as 2 mm were identified. For detection of hepatic nodules per mouse the sensitivity was 75%, the specificity was 100% and the accuracy was 88.5%. For detection of hepatic focal lesions per lesions the overall sensitivity was 60%, the specificity was 97%, and the accuracy was 75.9%. Contrast-enhanced harmonic ultrasound imaging did not improve the identification of the lesions in our experimental conditions. Conclusion: High-frequency ultrasound appears to be an efficient tool allowing new possibilities to use this animal model and evaluate new therapies in longitudinal studies, which are much more powerful. [source] Imaging of the Calf Vocal Fold With High-Frequency Ultrasound,THE LARYNGOSCOPE, Issue 10 2008Conor J. Walsh MSME Abstract Objectives/Hypothesis: High-frequency ultrasound imaging offers the potential for assisting in the diagnosis and treatment of vocal fold pathology if it allows aspects of vocal fold microstructure to be visualized noninvasively. The objective of this study was to assess the ability of high-frequency ultrasound to image vocal fold anatomy and injected biomaterials. Study Design: The vocal folds of two excised calf larynges were imaged ex vivo and compared with corresponding histological sections. Methods: High-frequency ultrasound imaging was performed under saline submersion using 40 and 50 MHz transducers, and corresponding cryostat cross-sections were stained with H&E, Trichome, and Verhoeff's Van Gieson stains. Results: The epithelial surface, lamina propria, and underlying muscle were easily identified with the high-frequency ultrasound as verified with histological sections representing each imaged region. The arytenoid cartilage vocal process can also be clearly distinguished from the surrounding tissue, as can the full extent of injected biomaterials within the superficial lamina propria. Useful ultrasound resolution was obtained to depths of at least 10 mm within the tissue with the 40 MHz transducer. Conclusions: This preliminary study demonstrates the capability of high-frequency ultrasound to image the layered anatomy of the calf vocal fold and to discern materials injected into the superficial lamina propria, indicating that this technology holds a strong potential for use in phonosurgery. [source] Evaluation of the atrophogenic potential of different glucocorticoids using optical coherence tomography, 20-MHz ultrasound and profilometry; a double-blind, placebo-controlled trialBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2006M. Coßmann Summary Background, Skin atrophy is one of the main side-effects of topical corticosteroid therapy. Although the use of high-frequency ultrasound is an established method that has been studied previously, it allows measurements of the slow-reacting dermal thickness only. Objectives, To investigate the decreasing epidermal thickness, which occurs earlier, we used optical coherence tomography (OCT), a high-resolution noninvasive imaging technique, and compared it with 20-MHz ultrasound and profilometry. Patients/methods, In this double-blind placebo-controlled trial 20 healthy volunteers applied four different corticosteroids and the cream base formulation as placebo to the volar part of both arms once a day over a 4-week period. The epidermal thickness, the dermal thickness and the skin surface roughness were assessed using OCT, high-frequency ultrasound and profilometry. Results, Each of the three methods allowed the detection and monitoring of significant corticosteroid-induced skin atrophy and its reversibility. The changes correlated with the potency of the steroids. The epidermal thickness decreased significantly in all test areas, even in the placebo and the untreated fields. As expected, the reduction in epidermal thickness was more pronounced and could be detected earlier by OCT than the reduction of dermal thickness using ultrasound. The epidermal surface roughness investigated using profilometry showed a slight smoothing. Conclusions, OCT allows a simple, fast and noninvasive in vivo measurement of the epidermal thickness. To evaluate the atrophogenic potential of corticosteroids it is more suitable than high-frequency ultrasound as epidermal thickness decreases earlier. In addition, epidermal thickness is a more sensitive indicator of steroid atrophy as the degree of thinning is much higher compared with the dermal atrophy. Profilometry might give further information; however, it would not be suitable for clinical use as the results were generally less pronounced. In the future, OCT might be useful to detect corticosteroid-induced side-effects at the beginning for monitoring the therapy. [source] | ||||||||||