Photoacoustic Imaging - Principles, Advances and Applications最新文献

Determination of the Source Localization and the Beginning Time of the Acoustic Signal 声源定位和声信号起始时间的确定

Photoacoustic Imaging - Principles, Advances and Applications Pub Date : 2020-02-18 DOI: 10.5772/intechopen.91199

R. Romanyshyn, G. Romanyshyn, I. Romanyshyn

{"title":"Determination of the Source Localization and the Beginning Time of the Acoustic Signal","authors":"R. Romanyshyn, G. Romanyshyn, I. Romanyshyn","doi":"10.5772/intechopen.91199","DOIUrl":"https://doi.org/10.5772/intechopen.91199","url":null,"abstract":"For the problem of PAT, that is, determining the coordinates and the beginning time of an acoustic signal, it is necessary to carry out synchronized registration of acoustic signals of a source using a multichannel receiving system. Synchronously recorded signals are the signals with a delayed (long) front. A threshold method is proposed for determining the arrival time of noisy acoustic signals with a delayed front based on the evaluation of an adaptive threshold. An approach that allows to reduce the problem of determining the coordinates and the beginning time of an acoustic signal to solving a system of linear algebraic equations is proposed. Matrix A of the system of linear algebraic equations depends on the arrival times of synchronized registered signals (source coordinates). Therefore, when collecting data for a given geometry of the product and the location of the receivers, it is necessary to calculate areas, where matrix A is ill-conditioned. Areas of poor conditionality of matrix A should be excluded from the permissible areas of location of sources of acoustic signals. For these areas there will certainly be poor accuracy. The results of simulation and experimental testing of the developed PAT technologies are presented.","PeriodicalId":360243,"journal":{"name":"Photoacoustic Imaging - Principles, Advances and Applications","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114515427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Photoacoustic Spectroscopy of Gaseous and Condensed Matter 气体和凝聚态物质的光声光谱

Photoacoustic Imaging - Principles, Advances and Applications Pub Date : 2019-10-25 DOI: 10.5772/intechopen.88840

S. Thakur

引用次数: 0

Photoacoustic Imaging in Gastroenterology: Advances and Needs 光声成像在胃肠病学:进展和需要

Photoacoustic Imaging - Principles, Advances and Applications Pub Date : 2019-05-08 DOI: 10.5772/INTECHOPEN.86051

Sheena R. Bhushan, S. Anandasabapathy, E. Petrova

{"title":"Photoacoustic Imaging in Gastroenterology: Advances and Needs","authors":"Sheena R. Bhushan, S. Anandasabapathy, E. Petrova","doi":"10.5772/INTECHOPEN.86051","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.86051","url":null,"abstract":"Gastroenterologists routinely use optical imaging and ultrasound for the minimally invasive diagnosis and treatment of chronic inflammatory diseases and cancerous tumors in gastrointestinal tract and related organs. Recent advances in gastroenterological photoacoustics represent combination of multispectral and multiscale photoacoustic (PA), ultrasound (US), and near-infrared (NIR) fluorescent imaging. The novel PA endoscopic methods have been evaluated in preclinical models using catheter-based miniature probes either noncontact, all-optical, forward-viewing probe or contact, side-viewing probe combined with ultrasound (esophagus and colon). The deep-tissue PA tomography has been applied to preclinical research on targeted contrast agents (pancreatic cancer) using benchtop experimental setups. The clinical studies engaging human tissue ex vivo have been performed on endoscopic mucosal resection tissue with PA-US tomography system and intraoperative imaging of pancreatic tissue with PA and NIR fluorescence multimodality. These emerging PA methods are very promising for early cancer detection and prospective theranostics. The noninvasive transabdominal examination with PA-US handheld probe has been implemented into clinical trials for the assessment of inflammatory bowel disease. To facilitate translational and clinical research in PA imaging in gastroenterology, we discuss potential clinical impact and limitations of the proposed solutions and future needs.","PeriodicalId":360243,"journal":{"name":"Photoacoustic Imaging - Principles, Advances and Applications","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127301005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Photoacoustic Imaging of the Eye 眼睛的光声成像

Photoacoustic Imaging - Principles, Advances and Applications Pub Date : 2019-04-27 DOI: 10.5772/INTECHOPEN.86050

Yanxiu Li, Y. Paulus

{"title":"Photoacoustic Imaging of the Eye","authors":"Yanxiu Li, Y. Paulus","doi":"10.5772/INTECHOPEN.86050","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.86050","url":null,"abstract":"Photoacoustic imaging (PAI) is a novel, hybrid, non-ionizing, and non-invasive imaging technology with high-resolution, high sensitivity, high-contrast, and high depth of penetration. Hence, it has particularly useful applications in eye investiga-tions. It can provide both anatomic and functional ocular characterizations. Many eye diseases, including macular degeneration and diabetic retinopathy, involve abnormalities in the vasculature, and thus the ability of PAI to affectively visualize the vasculature can be incredibly helpful to evaluate normal and disease states of the eye. In future research, PAI of the eye can be dramatically improved in terms of its resolution, use of contrast agents for molecular imaging, safety evaluations to develop a clinically approved system, and integration with existing fundus imaging modalities. Multimodality ocular imaging platforms have also been successfully developed by a combination of photoacoustic microscopy (PAM) with other optical imaging such as optical coherence tomography (OCT), scanning laser ophthalmoscopy (SLO), and fluorescence microscopy (FM). The multimodal images can accurately be acquired from a single imaging system and co-registered on the same image plane, enabling improved evaluation of eye disease states. In this book chapter, the potential application of photoacoustic imaging of the eye in both research and clinical diagnosis are comprehensively discussed as a powerful medical screening technique for visualization of various ocular diseases.","PeriodicalId":360243,"journal":{"name":"Photoacoustic Imaging - Principles, Advances and Applications","volume":"85 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132920643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3