for Journals by Title or ISSN
for Articles by Keywords
help
Followed Journals
Journal you Follow: 0
 
Sign Up to follow journals, search in your chosen journals and, optionally, receive Email Alerts when new issues of your Followed Journals are published.
Already have an account? Sign In to see the journals you follow.
Journal Cover Ultrasonic Imaging
  [SJR: 0.818]   [H-I: 34]   [1 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0161-7346 - ISSN (Online) 1096-0910
   Published by Sage Publications Homepage  [835 journals]
  • Foreword to the Special Issue of Ultrasonic Imaging on Biomedical Imaging
           with Combined Light and Sound
    • Authors: Wang, X; Feleppa, E.
      Pages: 3 - 4
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615622835
      Issue No: Vol. 38, No. 1 (2015)
       
  • Ultrasound-Guided Diffuse Optical Tomography for Predicting and Monitoring
           Neoadjuvant Chemotherapy of Breast Cancers: Recent Progress
    • Authors: Xu, C; Vavadi, H, Merkulov, A, Li, H, Erfanzadeh, M, Mostafa, A, Gong, Y, Salehi, H, Tannenbaum, S, Zhu, Q.
      Pages: 5 - 18
      Abstract: In this manuscript, we review the current progress of utilizing ultrasound-guided diffuse optical tomography (US-guided DOT) for predicting and monitoring neoadjuvant chemotherapy (NAC) outcomes of breast cancer patients. We also report the recent advance on optical tomography systems toward portable and robust clinical use at multiple clinical sites. The first patient who has been closely monitored before NAC, at day 2, day 8, end of first three cycles of NAC, and before surgery is given as an example to demonstrate the potential of US-guided DOT technique.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615580280
      Issue No: Vol. 38, No. 1 (2015)
       
  • Dual Modality Noncontact Photoacoustic and Spectral Domain OCT Imaging
    • Authors: Leiss-Holzinger, E; Bauer-Marschallinger, J, Hochreiner, A, Hollinger, P, Berer, T.
      Pages: 19 - 31
      Abstract: We developed a multimodal imaging system, combining noncontact photoacoustic imaging and optical coherence tomography (OCT). Photoacoustic signals are recorded without contact to the specimens’ surface by using an interferometric technique. The interferometer is realized within a fiber-optic network using a fiber laser at 1550 nm as source. The fiber-optic network allows the integration of a fiber-based OCT system operating at a wavelength region around 1310 nm. Light from the fiber laser and the OCT source are multiplexed into one fiber using wavelength-division multiplexing. The same focusing optics is used for both modalities. Back-reflected light from the sample is demultiplexed and guided to the respective imaging systems. As the same optical components are used for OCT and photoacoustic imaging, the obtained images are co-registered intrinsically in lateral direction. Three-dimensional imaging is implemented by hybrid galvanometer and mechanical scanning. To allow fast B-scan measurements, scanning of the interrogation beam along one dimension is executed by a galvanometer scanner. Slow-axis scanning, perpendicular to the fast axis, is performed utilizing a linear translational stage. We demonstrate two-dimensional and three-dimensional imaging on agarose phantoms.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615582003
      Issue No: Vol. 38, No. 1 (2015)
       
  • Coherence-Weighted Synthetic Focusing Applied to Photoacoustic Imaging
           Using a High-Frequency Annular-Array Transducer
    • Authors: Chitnis, P. V; Aristizabal, O, Filoux, E, Sampathkumar, A, Mamou, J, Ketterling, J. A.
      Pages: 32 - 43
      Abstract: This paper presents an adaptive synthetic-focusing scheme that, when applied to photoacoustic (PA) data acquired using an annular array, improves focusing across a greater imaging depth and enhances spatial resolution. The imaging system was based on a 40-MHz, 5-element, annular-array transducer with a focal length of 12 mm and an 800-µm diameter hole through its central element to facilitate coaxial delivery of 532-nm laser. The transducer was raster-scanned to facilitate 3D acquisition of co-registered ultrasound and PA image data. Three synthetic-focusing schemes were compared for obtaining PA A-lines for each scan location: delay-and-sum (DAS), DAS weighted with a coherence factor (DAS + CF), and DAS weighted with a sign-coherence factor (DAS + SCF). Bench-top experiments that used an 80-µm hair were performed to assess the enhancement provided by the two coherence-based schemes. Both coherence-based schemes increased the signal-to-noise ratio by approximately 10 dB. When processed using the DAS-only scheme, the lateral dimension of the hair in a PA image with 20 dB dynamic range was between 300 µm and 1 mm for imaging depth ranging from 8 to 20 mm. In comparison, the DAS + CF scheme resulted in a lateral dimension of 200 to 450 µm over the same range. The DAS + SCF synthetic focusing further improved the smallest-resolvable dimension, which was between 150 and 400 µm over the same range of imaging depth. When used on PA data obtained from a 12-day-old mouse embryo, the DAS + SCF processing improved visualization of neurovasculature.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615583981
      Issue No: Vol. 38, No. 1 (2015)
       
  • Multiscale Functional and Molecular Photoacoustic Tomography
    • Authors: Yao, J; Xia, J, Wang, L. V.
      Pages: 44 - 62
      Abstract: Photoacoustic tomography (PAT) combines rich optical absorption contrast with the high spatial resolution of ultrasound at depths in tissue. The high scalability of PAT has enabled anatomical imaging of biological structures ranging from organelles to organs. The inherent functional and molecular imaging capabilities of PAT have further allowed it to measure important physiological parameters and track critical cellular activities. Integration of PAT with other imaging technologies provides complementary capabilities and can potentially accelerate the clinical translation of PAT.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615584312
      Issue No: Vol. 38, No. 1 (2015)
       
  • A Method for Delineation of Bone Surfaces in Photoacoustic Computed
           Tomography of the Finger
    • Authors: Biswas, S. K; van Es, P, Steenbergen, W, Manohar, S.
      Pages: 63 - 76
      Abstract: Photoacoustic (PA) imaging of interphalangeal peripheral joints is of interest in the context of using the synovial membrane as a surrogate marker of rheumatoid arthritis. Previous work has shown that ultrasound (US) produced by absorption of light at the epidermis reflects on the bone surfaces within the finger. When the reflected signals are backprojected in the region of interest, artifacts are produced, confounding interpretation of the images. In this work, we present an approach where the PA signals known to originate from the epidermis are treated as virtual US transmitters, and a separate reconstruction is performed as in US reflection imaging. This allows us to identify the bone surfaces. Furthermore, the identification of the joint space is important as this provides a landmark to localize a region-of-interest in seeking the inflamed synovial membrane. The ability to delineate bone surfaces allows us to identify not only the artifacts but also the interphalangeal joint space without recourse to new US hardware or a new measurement. We test the approach on phantoms and on a healthy human finger.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615589288
      Issue No: Vol. 38, No. 1 (2015)
       
  • Three-Dimensional Optoacoustic and Laser-Induced Ultrasound Tomography
           System for Preclinical Research in Mice: Design and Phantom Validation
    • Authors: Ermilov, S. A; Su, R, Conjusteau, A, Anis, F, Nadvoretskiy, V, Anastasio, M. A, Oraevsky, A. A.
      Pages: 77 - 95
      Abstract: In this work, we introduce a novel three-dimensional imaging system for in vivo high-resolution anatomical and functional whole-body visualization of small animal models developed for preclinical and other type of biomedical research. The system (LOUIS-3DM) combines a multiwavelength optoacoustic tomography (OAT) and laser-induced ultrasound tomography (LUT) to obtain coregistered maps of tissue optical absorption and speed of sound, displayed within the skin outline of the studied animal. The most promising applications of the LOUIS-3DM include 3D angiography, cancer research, and longitudinal studies of biological distributions of optoacoustic contrast agents.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615591163
      Issue No: Vol. 38, No. 1 (2015)
       
  • Multi-Wavelength Photoacoustic Visualization of High Intensity Focused
           Ultrasound Lesions
    • Authors: Gray, J. P; Dana, N, Dextraze, K. L, Maier, F, Emelianov, S, Bouchard, R. R.
      Pages: 96 - 112
      Abstract: High intensity focused ultrasound (HIFU) thermal therapies are limited by deficiencies in existing image-guidance techniques. Previous studies using single-wavelength photoacoustic (PA) imaging have demonstrated that HIFU lesions generate contrast with respect to native tissues but have not sufficiently assessed lesion extent. The purpose of this study is to demonstrate feasibility of characterization of in vitro HIFU ablation lesion dimensions using 3D multi-wavelength PA imaging. Fresh porcine cardiac and liver tissue samples were embedded in agar phantoms and ablated using a 2.5 MHz small-animal HIFU system. Both 2D and 3D multi-wavelength photoacoustic-ultrasonic (PAUS) scans were performed in the near-infrared (NIR) range to characterize the change in the absorption spectrum of tissues following ablation and were compared to stained gross pathology to assess treatment margins and lesion extent. Comprehensive 2D multi-wavelength PA imaging yielded a spectrum in ablated tissue that did not display the characteristic local maximum in the optical absorption spectrum of deoxy-hemoglobin (Hb) near 760 nm. Two-dimensional tissue characterization map (TCM) images reconstructed from 3D TCM volumes reliably characterized lesion area and showed >70% area agreement with stained gross pathology. In addition, tissue samples were heated via water bath and concurrently interrogated with 2D PAUS imaging. PA signal exhibited an initial amplitude increase across all wavelengths, corresponding to an initial temperature increase, before then exhibiting a spectral change. This study suggests that multi-wavelength PA imaging has potential to obtain accurate characterization of HIFU lesion extent and may be better suited to guide HIFU ablation therapies during clinical treatments than single-wavelength methods.
      PubDate: 2015-12-16T02:19:17-08:00
      DOI: 10.1177/0161734615593747
      Issue No: Vol. 38, No. 1 (2015)
       
 
 
JournalTOCs
School of Mathematical and Computer Sciences
Heriot-Watt University
Edinburgh, EH14 4AS, UK
Email: journaltocs@hw.ac.uk
Tel: +00 44 (0)131 4513762
Fax: +00 44 (0)131 4513327
 
About JournalTOCs
API
Help
News (blog, publications)
JournalTOCs on Twitter   JournalTOCs on Facebook

JournalTOCs © 2009-2015