[ { "id": "authors:jcr8g-1bs45", "collection": "authors", "collection_id": "jcr8g-1bs45", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180919-160039145", "type": "book_section", "title": "Photoacoustic microscopy with submicron resolution", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2010", "author": [ { "family_name": "Maslov", "given_name": "Konstantin", "orcid": "0000-0003-3408-8840", "clpid": "Maslov-K-I" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "We show that it is possible to obtain high optical contrast photoacoustic images of tissue with 0.55 \u03bcm transverse resolution. To achieve high sensitivity, we used a high NA (0.85), 125 MHz spherically focused ultrasonic transducer in a confocal arrangement with a high resolution optical objective (NA=0.6). Laser pulses of a few nJ in pulse energy with durations of 1.5 ns at a 20 KHz pulse repetition rate were used to generate photoacoustic waves. Although the penetration depth is limited to hundreds of microns by both optical scattering and ultrasonic absorption, the developed technique can compete with optical microscopy, for example, in quantitative spectral measurements, in microcirculation research, or in nanoparticle detection.", "doi": "10.1117/12.841919", "isbn": "9780819479600", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2010-02-23", "pages": "Art. No. 75640W" }, { "id": "authors:wnrp9-xw230", "collection": "authors", "collection_id": "wnrp9-xw230", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-100906917", "type": "book_section", "title": "Novel breast cancer detection system combining both thermoacoustic (TA) and photoacoustic (PA) tomography using carbon nanotubes (CNTs) as a dual contrast agent", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2009", "author": [ { "family_name": "Pramanik", "given_name": "Manojit", "clpid": "Pramanik-M" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Li", "given_name": "Changhui", "clpid": "Li-Changhui" }, { "family_name": "Swierczewska", "given_name": "Magdalena", "clpid": "Swierczewska-M" }, { "family_name": "Green", "given_name": "Danielle", "clpid": "Green-D" }, { "family_name": "Sitharaman", "given_name": "Balaji", "clpid": "Sitharaman-B" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "We report here a novel breast cancer scanner using microwave and light excitation and ultrasound detection. This combined thermoacoustic and photoacoustic tomography scanner is a nonionizing low cost system that can potentially provide high-resolution, dual contrast (microwave and light absorption) three dimensional images of the breast. Front breast compression will be used in this scanner to alleviate patient discomfort, experienced in side breast compression during traditional X-ray mammography. This scanner will use dry instead of gel ultrasonic coupling. We have also developed a carbon nanotube-based contrast agent for both thermoacoustic and photoacoustic imaging. In the future, targeted molecular photoacoustic and thermoacoustic imaging should be possible using this contrast agent.", "doi": "10.1117/12.809230", "isbn": "9780819474230", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2009-02-24", "pages": "Art. No. 71772G" }, { "id": "authors:p5dsw-xyw15", "collection": "authors", "collection_id": "p5dsw-xyw15", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-100905238", "type": "book_section", "title": "In-vivo imaging of microcirculation using integrated photoacoustic and optical-coherence microscopy", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2009", "author": [ { "family_name": "Li", "given_name": "Li", "clpid": "Li-Li" }, { "family_name": "Maslov", "given_name": "Konstantin I.", "orcid": "0000-0003-3408-8840", "clpid": "Maslov-K-I" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Photoacoustic imaging and optical coherence tomography have complementary imaging contrasts. Photoacoustic imaging is sensitive to optical absorption, thus is able to generate detailed maps of deep microvasculature in vivo. Optical coherence tomography exploits the optical scattering contrast, and can provide real-time, micrometer-resolution imaging of tissue. We integrate an optical-resolution photoacoustic microscopy and a spectral-domain optical coherence tomography into a single system. Our preliminary experiments showed that it could be a valuable imaging tool for microcirculation studies in vivo.", "doi": "10.1117/12.809323", "isbn": "9780819474230", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2009-02-24", "pages": "Art. No. 71770I" }, { "id": "authors:qbs6h-spn32", "collection": "authors", "collection_id": "qbs6h-spn32", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-100904263", "type": "book_section", "title": "Multi-bandwidth image reconstruction in photoacoustic tomography", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2008: The Ninth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Chou", "given_name": "Cheng-Ying", "clpid": "Chou-Cheng-Ying" }, { "family_name": "Anastasio", "given_name": "Mark A.", "orcid": "0000-0002-3192-4172", "clpid": "Anastasio-M-A" }, { "family_name": "Zhang", "given_name": "Jin", "clpid": "Zhang-Jin" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Yang", "given_name": "Xinmai", "clpid": "Yang-Xinmai" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Photoacoustic tomography (PAT), also referred to optoacoustic tomography, is a hybrid imaging technique that combines an optical contrast mechanism and ultrasonic detection principles. The laser-induced photoacoustic signals in PAT are broadband in nature, but only a bandpass approximation of the signal is recorded by use of a conventional ultrasonic transducers due to its limited bandwidth. To circumvent this, a PAT system has been developed that records photoacoustic signals by use of multiple ultrasonic transducers that possess different central frequencies. In this work, we investigate a sensor fusion methodology for combining the multiple measurements to obtain an estimate of the true photoacoustic signal that is superior to that obtainable by use of any single transducer measurement. From the estimated photoacoustic signals, three-dimensional images of the optical absorption distribution are reconstructed and are found to possess improved accuracy and statistical properties as compared to the single transducer case. Preliminary computer-simulation studies are presented to demonstrate and investigate the proposed method.", "doi": "10.1117/12.764127", "isbn": "9780819470317", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2008-02-28", "pages": "Art. No. 68561G" }, { "id": "authors:6v9q8-bc581", "collection": "authors", "collection_id": "6v9q8-bc581", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-100904638", "type": "book_section", "title": "RF diffraction effect in RF-induced thermoacoustic tomography: calibration and distortion", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2008: The Ninth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Li", "given_name": "Changhui", "clpid": "Li-Changhui" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Manojit", "given_name": "Pramanik", "clpid": "Manojit-P" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Because the wavelengths of radio-frequency (RF) waves used in thermoacoustic tomography (TAT) are comparable with the size of detected objects, RF diffraction plays important roles in TAT. The RF diffraction affects not only the global distribution of the RF field in the tissue, but also local RF energy deposition. In this paper, we discussed these two major effects. Both numerical simulations and phantom experiments are done to demonstrate these phenomena. We also provide a partial correction method for the image distortion and a calibration algorithm for image calibration.", "doi": "10.1117/12.763450", "isbn": "9780819470317", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2008-02-28", "pages": "Art. No. 685612" }, { "id": "authors:g1j6y-ss644", "collection": "authors", "collection_id": "g1j6y-ss644", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-100904170", "type": "book_section", "title": "Improving the image quality of photoacoustic tomography (PAT) by using a negative acoustic lens", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2008: The Ninth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Li", "given_name": "Changhui", "clpid": "Li-Changhui" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Although a small point ultrasound transducer has a wide acceptance angle, its signal-to-noise (SNR) is low due to the high thermal-noise-induced electric voltages in the transducer, which is a result of its small active area. By contrast, a finite size flat transducer has high sensitivity (good SNR), but the acceptance angle is generally small, which limits its application in reconstruction-based photoacoustic tomography (PAT). In this paper, we report a negative lens concept to increase the acceptance angle for a flat transducer. We also provide phantom experiments that demonstrate this concept can greatly increase the detection region for PAT and without losing sensitivity.", "doi": "10.1117/12.763533", "isbn": "9780819470317", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2008-02-28", "pages": "Art. No. 685623" }, { "id": "authors:0m30f-cmh75", "collection": "authors", "collection_id": "0m30f-cmh75", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180921-100902463", "type": "book_section", "title": "Adaptive and robust techniques (ART) for thermoacoustic and photoacoustic tomography", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2007: The Eighth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Xie", "given_name": "Yao", "clpid": "Xie-Yao" }, { "family_name": "Guo", "given_name": "Bin", "clpid": "Guo-Bin" }, { "family_name": "Li", "given_name": "Jian", "orcid": "0000-0003-0297-6528", "clpid": "Li-Jian" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "In this paper, we present new Adaptive and Robust Techniques (ART) for microwave-based thermoacoustic tomography (TAT) and laser-based photo-acoustic tomography (PAT), and study their performances for breast cancer detection. TAT and PAT are emerging medical imaging techniques that combine the merits of high contrast due to electromagnetic or laser stimulation and high resolution offered by thermal acoustic imaging. The current image reconstruction methods used for TAT and PAT, such as the widely used Delay-and-Sum (DAS) approach, are data-independent and suffer from low resolution, high sidelobe levels, and poor interference rejection capabilities. The data-adaptive ART can have much better resolution and much better interference rejection capabilities than their data-independent counterparts. By allowing certain uncertainties, ART can be used to mitigate the amplitude and phase distortion problems encountered in TAT and PAT. Specifically, in the first step of ART, RCB is used for waveform estimation by treating the amplitude distortion with an uncertainty parameter. In the second step of ART, a simple yet effective peak searching method is used for phase distortion correction. Compared with other energy or amplitude based response intensity estimation methods, peak searching can be used to improve image quality with little additional computational costs. Moreover, since the acoustic pulse is usually bipolar: a positive peak, corresponding to the compression pulse, and a negative peak, corresponding to the rarefaction pulse, we can further enhance the image contrast in TAT or PAT by using the peak-to-peak difference as the response intensity for a focal point. The excellent performance of ART is demonstrated using both simulated and experimentally measured data.", "doi": "10.1117/12.698391", "isbn": "9780819465504", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2007-02-13", "pages": "Art. No. 643715" }, { "id": "authors:9dm8c-9rj87", "collection": "authors", "collection_id": "9dm8c-9rj87", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181107-143143362", "type": "book_section", "title": "Photoacoustic and thermoacoustic tomography with both optical and electrical contrasts", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2006: The Seventh Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "The absorption of electromagnetic energy causes thermal expansion and induces acoustic waves in biological tissues. Various tissues present particular characteristics in their absorption spectra. To acquire both photoacoustic and thermoacoustic images with multiple contrasts that reflect the absorption of electromagnetic energy, biological tissues are stimulated using laser and microwave pulses, respectively. Muscles with a rich blood supply strongly absorb green optical radiation, which provides excellent optical contrast. High water content tissues, such as connective tissue and muscle tissue, display high contrast to fatty tissues when imaged using microwave radiation. Most cancerous tissues have higher water and ionic concentrations, two characteristics that are also associated with angiogenesis and hemoglobin oxygen saturation. Therefore, cancer diagnosis based on information from tissue properties over an electromagnetic spectrum from microwave to optical bands can be more accurate than was previously available.", "doi": "10.1117/12.646365", "isbn": "9780819461285", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2006-03-06", "pages": "Art. No. 608618" }, { "id": "authors:memws-nh639", "collection": "authors", "collection_id": "memws-nh639", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181107-111820114", "type": "book_section", "title": "Photoacoustic molecular imaging of small animals in vivo", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2006: The Seventh Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Li", "given_name": "Meng-Lin", "clpid": "Li-Meng-Lin" }, { "family_name": "Oh", "given_name": "Jung-Taek", "clpid": "Oh-Jung-Taek" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Wei", "orcid": "0000-0002-5257-7675", "clpid": "Wang-Wei" }, { "family_name": "Li", "given_name": "Chun", "clpid": "Li-Chun" }, { "family_name": "Similache", "given_name": "Sergiu", "clpid": "Similache-S" }, { "family_name": "Lungu", "given_name": "Gina F.", "clpid": "Lungu-Gina-F" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Molecular imaging is a newly emerging field in which the modern tools of molecular and cell biology have been married to state-of-the-art technologies for noninvasive imaging. The study of molecular imaging will lead to better methods for understanding biological processes as well as diagnosing and managing disease. Here we present noninvasive in vivo spectroscopic photoacoustic tomography (PAT)-based molecular imaging of \u03b1v\u03b23 integrin in a nude mouse U87 brain tumor. PAT combines high optical absorption contrast and high ultrasonic resolution by employing short laser pulses to generate acoustic waves in biological tissues through thermoelastic expansion. Spectroscopic PAT-based molecular imaging offers the separation of the contributions from different absorbers based on the differences in optical absorption spectra among those absorbers. In our case, in the near infrared (NIR) range, oxy-heamoglobin (O2Hb), deoxy-heamoglobin (HHb) and the injected \u03b1v\u03b23-targeted peptide-ICG conjugated NIR fluorescent contrast agent are the three main absorbers. Therefore, with the excitation by multiple wavelength laser pulses, spectroscopic PAT-based molecular imaging not only provides the level of the contrast agent accumulation in the U87 glioblastoma tumor, which is related to the metabolism and angiogenesis of the tumor, but also offers the information on tumor angiogenesis and tumor hypoxia.", "doi": "10.1117/12.645121", "isbn": "9780819461285", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2006-03-06", "pages": "Art. No. 608606" }, { "id": "authors:ppb4v-e3s86", "collection": "authors", "collection_id": "ppb4v-e3s86", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-143522670", "type": "book_section", "title": "Combined Photoacoustic and Molecular Fluorescence Imaging In Vivo", "book_title": "27th Annual International Conference of the IEEE Engineering in Medicine and Biology Society", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Oh", "given_name": "Jung-Taek", "clpid": "Oh-Jung-Taek" }, { "family_name": "Li", "given_name": "Meng-Lin", "clpid": "Li-Meng-Lin" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Ke", "given_name": "Shi", "clpid": "Ke-Shi" }, { "family_name": "Similache", "given_name": "Sergiu", "clpid": "Similache-S" }, { "family_name": "Li", "given_name": "Chun", "clpid": "Li-Chun" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" } ], "abstract": "Because of the overwhelming scattering of light in biological tissues, the spatial resolution and imaging depth of conventional fluorescent imaging is unsatisfactory. Therefore, we present a dual modality imaging technique by combining fluorescence imaging with high-resolution noninvasive photoacoustic tomography (PAT) for the study of an animal tumor model. PAT provides high-resolution structural images of tumor angiogenesis, and fluorescence imaging offers high sensitivity to molecular probes for tumor detection. Coregistration of the PAT and fluorescence images was performed on nude mice with M21 human melanoma cell lines with alpha_vbeta_3 integrin expression. An integrin alpha_vbeta_3-targeted peptide-ICG conjugated NIR fluorescent contrast agent was used as the molecular probe for tumor detection. PAT was employed to noninvasively image the brain structure and the angiogenesis associated with tumors in mice. The coregistration between the PAT and fluorescence images was used to visualize tumor location, angiogenesis, and brain structure simultaneously.", "doi": "10.1109/iembs.2005.1616374", "isbn": "0780387414", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2005-09", "pages": "190-192" }, { "id": "authors:r8f3k-xgh16", "collection": "authors", "collection_id": "r8f3k-xgh16", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180926-073142733", "type": "book_section", "title": "Functional photoacoustic tomography for non-invasive imaging of cerebral blood oxygenation and blood volume in rat brain in vivo", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2005: The Sixth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Based on the multi-wavelength laser-based photoacoustic tomography, non-invasive in vivo imaging of functional parameters, including the hemoglobin oxygen saturation and the total concentration of hemoglobin, in small-animal brains was realized. The high sensitivity of this technique is based on the spectroscopic differences between oxy- and deoxy-hemoglobin while its spatial resolution is bandwidth-limited by the photoacoustic signals rather than by the optical diffusion as in optical imaging. The point-by-point distributions of blood oxygenation and blood volume in the cerebral cortical venous vessels, altered by systemic physiological modulations including hyperoxia, normoxia and hypoxia, were visualized successfully through the intact skin and skull. This technique, with its prominent intrinsic advantages, can potentially accelerate the progress in neuroscience and provide important new insights into cerebrovascular physiology and brain function that are of great significance to the neuroscience community.", "doi": "10.1117/12.589680", "isbn": "9780819456717", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2005-04-25", "pages": "1-6" }, { "id": "authors:xzjgs-h3x04", "collection": "authors", "collection_id": "xzjgs-h3x04", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180926-074540100", "type": "book_section", "title": "Breast cancer imaging by microwave-induced thermoacoustic tomography", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2005: The Sixth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Xu", "given_name": "Minghua", "clpid": "Xu-Minghua" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Jin", "given_name": "Xing", "clpid": "Jin-Xing" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "We report a preliminary study of breast cancer imaging by microwave-induced thermoacoustic tomography. In this study, we built a prototype of breast cancer imager based on a circular scan mode. A 3-GHz 0.3~0.5-\u03bcs microwave is used as the excitation energy source. A 2.25-MHz ultrasound transducer scans the thermoacoustic signals. All the measured data is transferred to a personal computer for imaging based on our proposed back-projection reconstruction algorithms. We quantified the line spread function of the imaging system. It shows the spatial resolution of our experimental system reaches 0.5 mm. After phantom experiments demonstrated the principle of this technique, we moved the imaging system to the University of Texas MD Anderson Cancer Center to image the excised breast cancer specimens. After the surgery performed by the physicians at the Cancer Center, the excised breast specimen was placed in a plastic cylindrical container with a diameter of 10 cm; and it was then imaged by three imaging modalities: radiograph, ultrasound and thermoacoustic imaging. Four excised breast specimens have been tested. The tumor regions have been clearly located. This preliminary study demonstrated the potential of microwave-induced thermoacoustic tomography for applications in breast cancer imaging.", "doi": "10.1117/12.589128", "isbn": "9780819456717", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2005-04-25", "pages": "45-48" }, { "id": "authors:6fn88-9ph66", "collection": "authors", "collection_id": "6fn88-9ph66", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180926-080928662", "type": "book_section", "title": "Deep penetrating photoacoustic tomography in biological tissues", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2005: The Sixth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Photoacoustic tomography (PAT) in a circular scanning configuration was developed to image the deeply embedded optical heterogeneity in biological tissues. Based on the intrinsic contrast between blood and chicken breast muscle, an embedded blood object that was 5 cm deep in the tissue was detected using pulsed laser light at a wavelength of 1064 nm. Compared with detectors for flat active surfaces, cylindrically focused ultrasonic transducers can reduce the interference generated from the off-plane photoacoustic sources and make the image in the scanning plane clearer. While the optical penetration was optimized with near-infrared laser pulses of 800 nm in wavelength, the optical contrast was enhanced by indocyanine green (ICG) whose absorption peak matched the laser wavelength. This optimized PAT was able to image fine objects embedded at a depth of up to 5.2-cm, which is 6.2 times the 1/e optical penetration depth, in chicken breast muscle, at a resolution of < ~750 microns with a sensitivity of <7 pmol of ICG in blood. The resolution was found to deteriorate slowly with increasing imaging depth.", "doi": "10.1117/12.588798", "isbn": "9780819456717", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2005-04-25", "pages": "117-126" }, { "id": "authors:v9aqm-6ej06", "collection": "authors", "collection_id": "v9aqm-6ej06", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180926-080326321", "type": "book_section", "title": "Photoacoustic tomography and molecular fluorescence imaging: dual modality imaging of small animal brains in vivo", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2005: The Sixth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Oh", "given_name": "Jung-Taek", "clpid": "Oh-Jung-Taek" }, { "family_name": "Li", "given_name": "Meng-Lin", "clpid": "Li-Meng-Lin" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ke", "given_name": "Shi", "clpid": "Ke-Shi" }, { "family_name": "Li", "given_name": "Chun", "clpid": "Li-Chun" }, { "family_name": "Similache", "given_name": "Sergiu", "clpid": "Similache-S" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "We present a dual modality imaging technique by combining photoacoustic tomography (PAT) and near-infrared (NIR) fluorescence imaging for the study of animal model tumors. PAT provides high-resolution structural images of tumor angiogenesis, and fluorescence imaging offers high sensitivity to molecular probes for tumor detection. Coregistration of the PAT and fluorescence images was performed on nude mice with M21 human melanoma cell lines with \u03b1v\u03b23 integrin expression. An integrin \u03b1v\u03b23-targeted peptide-ICG conjugated NIR fluorescent contrast agent was used as the molecular probe for tumor detection. PAT was employed to noninvasively image the brain structures and the angiogenesis associated with tumors in nude mice. Coregistration of the PAT and fluorescence images was used in this study to visualize tumor location, angiogenesis, and brain structure simultaneously.", "doi": "10.1117/12.589670", "isbn": "9780819456717", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2005-04-25", "pages": "107-110" }, { "id": "authors:fmmdq-w6837", "collection": "authors", "collection_id": "fmmdq-w6837", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180926-110946396", "type": "book_section", "title": "Mitigating artifacts via half-time reconstruction in thermoacoustic tomography", "book_title": "Photons Plus Ultrasound: Imaging and Sensing 2005: The Sixth Conference on Biomedical Thermoacoustics, Optoacoustics, and Acousto-optics", "author": [ { "family_name": "Anastasio", "given_name": "Mark A.", "orcid": "0000-0002-3192-4172", "clpid": "Anastasio-M-A" }, { "family_name": "Zhang", "given_name": "Jin", "clpid": "Zhang-Jin" }, { "family_name": "Pan", "given_name": "Xiaochuan", "clpid": "Pan-Xiaochuan" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Thermoacoustic tomography (TAT) is an ultrasound-mediated biophotonic imaging modality with great potential for a wide range of biomedical imaging applications. In this work, we demonstrate that half-time reconstruction approaches for TAT can mitigate image artifacts due to heterogeneous acoustic properties of an object. We also discuss how half-time reconstruction approaches permit explicit control of statistically complementary information in the measurement data, which can facilitate the reduction of image variances.", "doi": "10.1117/12.589190", "isbn": "9780819456717", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2005-04-25", "pages": "263-270" }, { "id": "authors:r7mwz-0sa27", "collection": "authors", "collection_id": "r7mwz-0sa27", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-143522758", "type": "book_section", "title": "High-resolution spectroscopic photoacoustic tomography for non-invasive functional imaging of small-animal brains in vivo", "book_title": "Second Asian and Pacific Rim Symposium on Biophotonics, 2004", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" } ], "abstract": "Based on the multiwavelength laser-based photoacoustic tomography, noninvasive imaging of cerebral blood oxygenation and blood volume in small-animal brains in vivo was realized. The high sensitivity of this technique is based on the spectroscopic differences between oxy- and deoxy-hemoglobins whereas its spatial resolution is diffraction-limited by the photoacoustic signals. The point-by-point distributions of hemoglobin oxygen saturation and total concentration of hemoglobin in the cerebral cortical venous vessels, altered by systemic physiological modulations including hyperoxia and hypoxia, were visualized successfully through the intact skin and skull. This technique can potentially accelerate the progress in neuroscience and provide important new insights into cerebrovascular physiology and brain function.", "doi": "10.1109/apbp.2004.1412374", "isbn": "0780386760", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2004-12", "pages": "246-247" }, { "id": "authors:ka0h8-msc05", "collection": "authors", "collection_id": "ka0h8-msc05", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-143523017", "type": "book_section", "title": "High-resolution photoacoustic tomography", "book_title": "17th Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2004", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" } ], "abstract": "Optical contrast is sensitive to physiological parameters, such as the oxygen saturation and total concentration of hemoglobin, in biological tissues. Photoacoustic tomography is based on the high optical contrast yet utilizing the high ultrasonic resolution. Our work in this emerging area of research will be summarized in this invited talk. In this technology, a diffraction-based inverse-source problem is solved in the image reconstruction, for which we developed the rigorous reconstruction theory. We implemented a prototype and accomplished non-invasive transdermal and transcranial functional imaging of small-animal brains in vivo. Changes in the cerebral blood oxygenation and blood volume of a rat, as a result of the alternation from hyperoxia to hypoxia, were imaged successfully.", "doi": "10.1109/leos.2004.1363465", "isbn": "0780385578", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2004-11", "pages": "767-768" }, { "id": "authors:2gx69-6s513", "collection": "authors", "collection_id": "2gx69-6s513", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-140403933", "type": "book_section", "title": "High-resolution ultrasound-aided biophotonic imaging", "book_title": "26th Annual International Conference of the IEEE Engineering in Medicine and Biology Society", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" } ], "abstract": "Optical contrast is sensitive to functional parameters, including the oxygen saturation and total concentration of hemoglobin, in biological tissues. However, due to the overwhelming scattering encountered by light in tissues, traditional optical modalities cannot provide satisfactory spatial resolution beyond the ballistic (a few hundred microns) and quasiballistic (1-2 mm) regimes. Photoacoustic tomography is based on the high optical contrast yet utilizing the high ultrasonic resolution. Our work in this emerging area of research will be summarized in this invited talk. In this technology, a diffraction-based inverse-source problem is solved in the image reconstruction, for which we developed the rigorous reconstruction theory. We implemented a prototype and accomplished noninvasive transdermal and transcranial functional imaging of small-animal brains in vivo. Change in the cerebral blood oxygenation of a rat, as a result of the alternation from hyperoxia to hypoxia, was imaged successfully.", "doi": "10.1109/iembs.2004.1404482", "isbn": "0780384393", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2004-09", "pages": "5307-5310" }, { "id": "authors:35mgg-fmt44", "collection": "authors", "collection_id": "35mgg-fmt44", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180927-114226804", "type": "book_section", "title": "Photoacoustic tomography of rat brain in vivo using multibandwidth ultrasonic detection", "book_title": "Photons Plus Ultrasound: Imaging and Sensing", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Photoacoustic tomography employs short laser pulses to generate acoustic waves. The photoacoustic image of a test sample can be reconstructed using the detected acoustic signals. The reconstructed image is characterized by the convolution of the sample structure in optical absorption, the laser pulse, and the impulse response of the ultrasonic transducer used for detection. Although laser-induced ultrasonic waves cover a wide spectral range, a single transducer can receive only part of the spectrum because of its limited bandwidth. To systematically analyze this problem, we constructed a photoacoustic tomographic system that uses multiple ultrasonic transducers, each at a different central frequency, to simultaneously receive the induced acoustic waves. The photoacoustic images associated with the different transducers were compared and analyzed. The system was used to detect the vascular system of the rat brain. The vascular vessels in the brain cortex were revealed by all of the transducers, but the image resolutions differed. The higher frequency detectors with wider bandwidths provided better image resolution.", "doi": "10.1117/12.532195", "isbn": "9780819452283", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2004-07-12", "pages": "172-178" }, { "id": "authors:kejwg-dsz58", "collection": "authors", "collection_id": "kejwg-dsz58", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180927-114226623", "type": "book_section", "title": "Laser-induced photoacoustic tomography enhanced with an optical contrast agent", "book_title": "Photons Plus Ultrasound: Imaging and Sensing", "author": [ { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Wegiel", "given_name": "Malgorzata A.", "clpid": "Wegiel-M-A" }, { "family_name": "Bornhop", "given_name": "Darryl J.", "clpid": "Bornhop-D-J" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Optical contrast agents, such as indocyanine dyes, nano-particles and their functional derivatives, have been widely applied to enhance the sensitivity and specificity of optical imaging. However, due to the overwhelming scattering of light in biological tissues, the spatial resolution of traditional optical imaging degrades drastically as the imaging depth increases. For the first time to our knowledge, non-invasive in vivo photoacoustic imaging of an optical contrast agent, distributed in the rat brain, was implemented with near-infrared light. Injection of indocyanine green polyethylene glycol, a contrast agent with a high absorption at the 805-nm wavelength, into the circulatory system of a rat enhanced the absorption contrast between the blood vessels and the background brain tissues. Because near-infrared light can penetrate deep into the brain tissues through the skin and skull, we were able to successfully reconstruct the vascular distribution in the rat brain from the detected photoacoustic signals. The dynamic concentration of this contrast agent in the brain blood after the intravenous injection was also studied. This work proved that the distribution of an exogenous contrast agent in biological tissues can be imaged clearly and accurately by photoacoustic tomography. This new technology has high potential for application in dynamic and molecular medical imaging.", "doi": "10.1117/12.532434", "isbn": "9780819452283", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2004-07-12", "pages": "77-82" }, { "id": "authors:vta87-ktq50", "collection": "authors", "collection_id": "vta87-ktq50", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180927-114227252", "type": "book_section", "title": "Non-invasive functional photoacoustic tomography of blood-oxygen saturation in the brain", "book_title": "Photons Plus Ultrasound: Imaging and Sensing", "author": [ { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Xie", "given_name": "Xueyi", "clpid": "Xie-Xueyi" }, { "family_name": "Wang", "given_name": "Yiwen", "clpid": "Wang-Yiwen" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" } ], "abstract": "Since optical contrast is sensitive to functional parameters, including the hemoglobin oxygen saturation and the total concentration of hemoglobin, imaging based on optical contrast has been widely employed for the real-time monitoring of tissue oxygen consumption and hemodynamics in biological tissues. However, due to the overwhelming scattering of light in tissues, traditional optical imaging modalities cannot provide satisfactory spatial resolution. Functional photoacoustic tomography is a novel technique that combines high optical contrast and high ultrasonic resolution. Here, we present our study of a laser-based photoacoustic technique that, for the first time to our knowledge, monitors blood oxygenation in the rat brain in vivo. The cerebral blood oxygenation in the rat brain was imaged by photoacoustic detection at two wavelengths. The change in the hemoglobin oxygen saturation in the brain vessels as a result of the alternation from hyperoxia status to hypoxia status was visualized successfully with satisfactory spatial resolution. This work demonstrates that photoacoustic technique, based on the spectroscopic absorption of oxy- and deoxy-hemoglobin, can provide accurate functional imaging of cerebral blood oxygenation in the small-animal brain non-invasively with the skin and skull intact.", "doi": "10.1117/12.532440", "isbn": "9780819452283", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2004-07-12", "pages": "69-76" }, { "id": "authors:wdw7f-rvz28", "collection": "authors", "collection_id": "wdw7f-rvz28", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-143522934", "type": "book_section", "title": "High-resolution functional photoacoustic tomography", "book_title": "2004 2nd IEEE International Symposium on Biomedical Imaging: Nano to Macro", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Wang", "given_name": "Xueding", "clpid": "Wang-Xueding" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Stoica", "given_name": "George", "orcid": "0000-0001-8071-4828", "clpid": "Stoica-G" } ], "abstract": "All-optical imaging has high contrast but poor spatial resolution beyond the ballistic and quasiballistic regimes. All-ultrasonic imaging has high spatial resolution but poor contrast for early stage tumors. Photoacoustic tomography combines the high optical contrast and the high ultrasonic resolution. Our work in this emerging area of research will be summarized in this invited talk. In this technology, a diffraction-based inverse-source problem is solved in the image reconstruction, for which our group developed the rigorous reconstruction theory. We developed a prototype and accomplished noninvasive transdermal and transcranial functional imaging of small-animal brains in vivo.", "doi": "10.1109/isbi.2004.1398829", "isbn": "0780383885", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2004-04", "pages": "1479-1481" }, { "id": "authors:f44rj-ec251", "collection": "authors", "collection_id": "f44rj-ec251", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-143524008", "type": "book_section", "title": "Combining microwave and ultrasound: scanning thermoacoustic tomography", "book_title": "Proceedings of the 22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "abstract": "Scanning thermoacoustic tomography based on microwave-induced thermoacoustic waves was studied. Two-dimensional images of /spl sim/50-mm thick biological tissue samples were obtained experimentally. The thermoacoustic signals were also simulated theoretically. The image resolution was significantly improved compared with purely microwave imaging.", "doi": "10.1109/iembs.2000.900607", "isbn": "0780364651", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2000-07", "pages": "2321-2323" }, { "id": "authors:90863-4pv81", "collection": "authors", "collection_id": "90863-4pv81", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190304-143523816", "type": "book_section", "title": "Hybrid medical imaging: scanning thermoacoustic tomography", "book_title": "Proceedings 13th IEEE Symposium on Computer-Based Medical Systems. CBMS 2000", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" } ], "abstract": "Scanning thermoacoustic tomography based on microwave-induced thermoacoustic waves studied. Two-dimensional images of /spl sim/50 mm thick biological tissue samples were obtained. The thermoacoustic signals were also simulated theoretically. The image resolution was significantly improved compared with purely microwave imaging.", "doi": "10.1109/cbms.2000.856890", "isbn": "0769504841", "publisher": "IEEE", "place_of_publication": "Piscataway, NJ", "publication_date": "2000-06", "pages": "129-134" }, { "id": "authors:sface-e5103", "collection": "authors", "collection_id": "sface-e5103", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181207-161547992", "type": "book_section", "title": "Scanning optoacoustic tomography with microwave radiation", "book_title": "Biomedical Optoacoustics", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Oraevsky", "given_name": "Alexander A.", "clpid": "Oraevsky-A-A" } ], "abstract": "Scanning thermoacoustic tomography based on microwave- induced thermoacoustic waves was studied. 2D images of approximately 50-mm thick biological tissue samples were obtained experimentally. The thermoacoustic signals were also simulated theoretically. The image resolution was significantly improved compared with purely microwave imaging.", "doi": "10.1117/12.386318", "isbn": "9780819435323", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "2000-05-19", "pages": "160-165" }, { "id": "authors:xzv4k-t9525", "collection": "authors", "collection_id": "xzv4k-t9525", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190305-153254127", "type": "book_section", "title": "Scanning thermoacoustic tomograhy in biological tissue", "book_title": "Biomedical Optical Spectroscopy and Diagnostics", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Wang", "given_name": "Lihong", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Li", "given_name": "T.", "clpid": "Li-T" } ], "abstract": "Thermoacoustic tomography in the microwave region is explored to image biological tissue. When short-pulse electromagnetic energy is deposited into tissue, acoustic waves are generated due to thermoelastic expansion. The microwave-induced acoustic wave is detected with a focused ultrasonic detector. Each time-domain signal from the ultrasonic transducer represents a one-dimensional image along the acoustic axis. Scanning the system generates multi-dimensional images. The time-domain acoustic signal was simulated theoretically and measured experimentally, where the theoretical and experimental results were in good agreement. Two-dimensional tomographic images of biological tissue were obtained experimentally. Thermoacoustic tomography combines the advantage of microwaves in imaging contrast and the advantage of acoustic waves in imaging resolution.", "doi": "10.1364/bosd.2000.tuc5", "isbn": "155752632X", "publisher": "Optical Society of America", "place_of_publication": "Washington, D.C.", "publication_date": "2000-04", "pages": "Art. No. TuC5" }, { "id": "authors:vw56j-5hz68", "collection": "authors", "collection_id": "vw56j-5hz68", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181207-161548152", "type": "book_section", "title": "Combining sound and light in scattering media", "book_title": "1999 International Conference on Biomedical Optics", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Shen", "given_name": "Qimin", "clpid": "Shen-Qimin" } ], "contributor": [ { "family_name": "Luo", "given_name": "Qingming", "clpid": "Luo-Qingming" }, { "family_name": "Chance", "given_name": "Britton", "clpid": "Chance-B" }, { "family_name": "Wang", "given_name": "Lihong V.", "clpid": "Wang-Lihong-V" }, { "family_name": "Jacques", "given_name": "Steven L.", "clpid": "Jacques-S-L" } ], "abstract": "Two imaging techniques combining ultrasound and light are reviewed. The motivation is to combine the advantages of optical information and acoustic imaging resolution. The first technique is sonoluminescence tomography, where a sonoluminescence signal generated internally in the media by continuous-wave ultrasound is used. 2D images can be produced for objects embedded in turbid media by raster scanning the media. The second technique is ultrasound-modulated optical tomography, where a frequency-swept ultrasonic wave was used to modulate the laser light passing through a scattering medium. Multiple 1D images obtained at various positions perpendicular to the ultrasonic axis were composed to obtain a 2D tomographic image of the medium.", "doi": "10.1117/12.364370", "isbn": "9780819434555", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "1999-09-17", "pages": "95-104" }, { "id": "authors:bdngw-v9815", "collection": "authors", "collection_id": "bdngw-v9815", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181210-161157461", "type": "book_section", "title": "Chirped ultrasound-modulated optical tomography", "book_title": "Optical Tomography and Spectroscopy of Tissue III", "author": [ { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Yao", "given_name": "Gang", "clpid": "Yao-Gang" }, { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" } ], "contributor": [ { "family_name": "Chance", "given_name": "Britton", "clpid": "Chance-B" }, { "family_name": "Alfano", "given_name": "Robert R.", "clpid": "Alfano-R-R" }, { "family_name": "Tromaberg", "given_name": "Bruce J.", "clpid": "Tromberg-B-J" } ], "abstract": "A novel chirped ultrasound-modulated optical tomography technique was developed to image turbid media. Frequency analysis was employed to obtain spatial resolution along the ultrasonic axis. 2D images from scattering medium were obtained. The chirped ultrasound modulated signal was detected in chicken breast tissue.", "doi": "10.1117/12.356831", "isbn": "9780819430670", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "1999-07-15", "pages": "371-375" }, { "id": "authors:4pt8w-1mh62", "collection": "authors", "collection_id": "4pt8w-1mh62", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181207-161548424", "type": "book_section", "title": "Sound and light in turbid media", "book_title": "Laser-Tissue Interaction X: Photochemical, Photothermal, and Photomechanical", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" }, { "family_name": "Shen", "given_name": "Qimin", "clpid": "Shen-Qimin" } ], "contributor": [ { "family_name": "Jacques", "given_name": "Steven L.", "clpid": "Jacques-S-L" }, { "family_name": "Mueller", "given_name": "Gerhard J.", "clpid": "Mueller-G-J" }, { "family_name": "Roggan", "given_name": "Andre", "clpid": "Roggan-A" }, { "family_name": "Sliney", "given_name": "David H.", "clpid": "SLiney-D-H" } ], "abstract": "Two imaging techniques combining ultrasound and light are reviewed. The motivation is to combine the advantages of optical information and acoustic imaging resolution. The first technique is sonoluminescence tomography, where a sonoluminescence signal generated internally in the media by continuous-wave ultrasound is used. Two-dimensional images can be produced for objects embedded in turbid media by raster scanning the media. The second technique is ultrasound- modulated optical tomography, where a frequency-swept ultrasonic wave was used to modulate the laser light passing through a scattering medium. Multiple 1D images obtained at various positions perpendicular to the ultrasonic axis were composed to obtain a 2D tomographic image of the medium.", "doi": "10.1117/12.350005", "isbn": "9780819430717", "publisher": "Society of Photo-optical Instrumentation Engineers (SPIE)", "place_of_publication": "Bellingham, WA", "publication_date": "1999-06-14", "pages": "238-247" }, { "id": "authors:vr65h-2cv54", "collection": "authors", "collection_id": "vr65h-2cv54", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190305-153255154", "type": "book_section", "title": "Frequency-swept ultrasound-modulated optical tomography", "book_title": "Advances in Optical Imaging and Photon Migration", "author": [ { "family_name": "Wang", "given_name": "Lihong V.", "orcid": "0000-0001-9783-4383", "clpid": "Wang-Lihong-V" }, { "family_name": "Ku", "given_name": "Geng", "clpid": "Ku-Geng" } ], "contributor": [ { "family_name": "Fujimoto", "given_name": "J.", "clpid": "Fujimoto-J" }, { "family_name": "Patterson", "given_name": "M.", "clpid": "Patterson-M" } ], "abstract": "A novel frequency-swept (chirped) ultrasound modulated optical tomography technique was developed to image scattering media. Laser light was modulated by a frequency-swept ultrasonic wave to add spatial information to the modulated optical signal. The modulated optical signal was received by a photomultiplier tube and was heterodyned with a reference modulation signal. Frequency analysis was employed to obtain spatial resolution along the ultrasonic axis. A spectrum can be converted to a ID image. Multiple spectra were obtained and were used to form a 2D image of the scattering medium.", "doi": "10.1364/aoipm.1998.awa3", "isbn": "1557525463", "publisher": "Optical Society of America", "place_of_publication": "Washington, D.C.", "publication_date": "1998-03", "pages": "Art. No. AWA3" } ]