Search results for "Sound"
showing 10 items of 1845 documents
A Computational Study on Temperature Variations in MRgFUS Treatments Using PRF Thermometry Techniques and Optical Probes
2021
Structural and metabolic imaging are fundamental for diagnosis, treatment and follow-up in oncology. Beyond the well-established diagnostic imaging applications, ultrasounds are currently emerging in the clinical practice as a noninvasive technology for therapy. Indeed, the sound waves can be used to increase the temperature inside the target solid tumors, leading to apoptosis or necrosis of neoplastic tissues. The Magnetic resonance-guided focused ultrasound surgery (MRgFUS) technology represents a valid application of this ultrasound property, mainly used in oncology and neurology. In this paper
Simultaneous remote extraction of multiple speech sources and heart beats from secondary speckles pattern
2009
The ability of dynamic extraction of remote sounds is very appealing. In this manuscript we propose an optical approach allowing the extraction and the separation of remote sound sources. The approach is very modular and it does not apply any constraints regarding the relative position of the sound sources and the detection device. The optical setup doing the detection is very simple and versatile. The principle is to observe the movement of the secondary speckle patterns that are generated on top of the target when it is illuminated by a spot of laser beam. Proper adaption of the imaging optics allows following the temporal trajectories of those speckles and extracting the sound signals ou…
Deformable object segmentation in ultra-sound images
2013
Breast cancer is the second most common type of cancer being the leading cause of cancer death among females both in western and in economically developing countries. Medical imaging is key for early detection, diagnosis and treatment follow-up. Despite Digital Mammography (DM) remains the reference imaging modality, Ultra-Sound (US) imaging has proven to be a successful adjunct image modality for breast cancer screening, specially as a consequence of the discriminative capabilities that US offers for differentiating between solid lesions that are benign or malignant. Despite US usability,US suffers inconveniences due to its natural noise that compromises the diagnosis capabilities of radio…
Depth determination of skin cancers treated with superficial brachytherapy: ultrasound vs. histopathology
2014
Purpose: The purpose of this study is to compare high frequency ultrasonography (HFUS) and histpathologic assessment done by punch biopsy in order to determine depth of basal cell carcinoma (BCC), in both superficial and nodular BCCs prior to brachytherapy treatment. Material and methods: This study includes 20 patients with 10 superficial and 10 nodular BCCs. First, punch biopsy was done to confirm the diagnosis and to measure tumour depth (Breslow rate). Subsequently, HFUS was done to measure tumour depth to search for correlation of these two techniques. Results: Neither clear tendency nor significance of the punch biopsy vs. HFUS depth determination is observed. Depth value differences …
Ostectomy versus osteotomy with repositioning of the vestibular cortical in periapical surgery of mandibular molars : a preliminary study
2010
Introduction: Accessing the tooth roots in periapical surgery (PS) requires the elimination of periapical bone. Objective: To compare the postoperative morbidity and prognosis following PS on mandibular molars by ostectomy, or by osteotomy with repositioning of the vestibular cortical. Material and Methods: A retrospective clinical study of mandibular molars subjected to PS with ultrasound. Two groups were considered according to the surgical procedure used to access the roots: Group 1 (G1) with ostectomy and Group 2 (G2) with osteotomy and repositioning of the vestibular cortical. Only patients who had properly followed the post-operative instructions, adequately completed the post-operati…
The application of the photoacoustic transmittance oscillations for determining elastic constants in gallium and indium selenides
1996
Transmittance periodic oscillations are observed in GaSe and InSe on excitation with optical pulses. Such oscillations are explained in terms of photoacoustic generation of dilatational waves, which become resonant within the crystal. Spectral analysis of those oscillations in samples of different thickness has led to an accurate determination of the longitudinal acoustic‐wave velocity along the crystallographic axis c. Julio.Pellicer@uv.es ; Chantal.Ferrer@uv.es ; Vicente.Munoz@uv.es
HIFU for Bone Metastases and other Musculoskeletal Applications
2018
AbstractHigh-intensity focused ultrasound (HIFU) is a totally noninvasive procedure that has shown promising results in the management of numerous malignant and nonmalignant conditions. Under magnetic resonance or ultrasound guidance, high-intensity ultrasound waves are focused on a small, well-defined target region, inducing biologic tissue heating and coagulative necrosis, thus resulting in a precise and localized ablation. This treatment has shown both great safety and efficacy profiles, and may offer a multimodal approach to different diseases, providing pain palliation, potential local tumor control, and, in some cases, remineralization of trabecular bone. In musculoskeletal field, HIF…
The Androgen Excess and PCOS Society criteria for the polycystic ovary syndrome: the complete task force report.
2009
Abstract OBJECTIVE: To review all available data and recommend a definition for polycystic ovary syndrome (PCOS) based on published peer-reviewed data, whether already in use or not, to guide clinical diagnosis and future research. DESIGN: Literature review and expert consensus. SETTING: Professional society. PATIENTS: None. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): A systematic review of the published peer-reviewed medical literature, by querying MEDLINE databases, to identify studies evaluating the epidemiology or phenotypic aspects of PCOS. RESULT(S): The Task Force drafted the initial report, following a consensus process via electronic communication, which was then reviewed and c…
Analyzing and organizing the sonic space of vocal imitations
2015
The sonic space that can be spanned with the voice is vast and complex and, therefore, it is difficult to organize and explore. In order to devise tools that facilitate sound design by vocal sketching we attempt at organizing a database of short excerpts of vocal imitations. By clustering the sound samples on a space whose dimensionality has been reduced to the two principal components, it is experimentally checked how meaningful the resulting clusters are for humans. Eventually, a representative of each cluster, chosen to be close to its centroid, may serve as a landmark in the exploration of the sound space, and vocal imitations may serve as proxies for synthetic sounds.
Early auditory processing in musicians and dancers during a contemporary dance piece
2016
AbstractThe neural responses to simple tones and short sound sequences have been studied extensively. However, in reality the sounds surrounding us are spectrally and temporally complex, dynamic and overlapping. Thus, research using natural sounds is crucial in understanding the operation of the brain in its natural environment. Music is an excellent example of natural stimulation which, in addition to sensory responses, elicits vast cognitive and emotional processes in the brain. Here we show that the preattentive P50 response evoked by rapid increases in timbral brightness during continuous music is enhanced in dancers when compared to musicians and laymen. In dance, fast changes in brigh…