Hamid Dehghani

Summary

Affiliation: Dartmouth Medical School
Country: USA

Publications

  1. ncbi request reprint Three-dimensional optical tomography: resolution in small-object imaging
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 42:3117-28. 2003
  2. ncbi request reprint Linear single-step image reconstruction in the presence of nonscattering regions
    H Dehghani
    Department of Medical Physics and Bioengineering, University College London, UK
    J Opt Soc Am A Opt Image Sci Vis 19:1162-71. 2002
  3. ncbi request reprint Multiwavelength three-dimensional near-infrared tomography of the breast: initial simulation, phantom, and clinical results
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 42:135-45. 2003
  4. ncbi request reprint Effects of refractive index on near-infrared tomography of the breast
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, New Hampshire 03755 8000, USA
    Appl Opt 44:1870-8. 2005
  5. ncbi request reprint Image reconstruction of effective Mie scattering parameters of breast tissue in vivo with near-infrared tomography
    Xin Wang
    Dartmouth College, Department of Physics and Astronomy, Hanover, New Hampshire 03755, USA
    J Biomed Opt 11:041106. 2006
  6. ncbi request reprint In vivo hemoglobin and water concentrations, oxygen saturation, and scattering estimates from near-infrared breast tomography using spectral reconstruction
    Subhadra Srinivasan
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Acad Radiol 13:195-202. 2006
  7. ncbi request reprint Spectrally constrained chromophore and scattering near-infrared tomography provides quantitative and robust reconstruction
    Subhadra Srinivasan
    Department of Biomedical Engineering, Thayer School of Engineering, Dartmouth College, P O Box 8000, Hanover, New Hampshire 03755, USA
    Appl Opt 44:1858-69. 2005
  8. ncbi request reprint Spectral priors improve near-infrared diffuse tomography more than spatial priors
    Ben Brooksby
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, New Hampshire 03755, USA
    Opt Lett 30:1968-70. 2005
  9. pmc Imaging breast adipose and fibroglandular tissue molecular signatures by using hybrid MRI-guided near-infrared spectral tomography
    Ben Brooksby
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
    Proc Natl Acad Sci U S A 103:8828-33. 2006
  10. ncbi request reprint Characterization of hemoglobin, water, and NIR scattering in breast tissue: analysis of intersubject variability and menstrual cycle changes
    Brian W Pogue
    Thayer School of Engineering, Dartmouth College, 800 Cummings Hall, Hanover, New Hampshire 03755, USA
    J Biomed Opt 9:541-52. 2004

Detail Information

Publications50

  1. ncbi request reprint Three-dimensional optical tomography: resolution in small-object imaging
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 42:3117-28. 2003
    ..Furthermore, the accuracy of quantitative imaging is increased to almost 100% of the target values when a priori information regarding the internal structure of imaging domain is utilized...
  2. ncbi request reprint Linear single-step image reconstruction in the presence of nonscattering regions
    H Dehghani
    Department of Medical Physics and Bioengineering, University College London, UK
    J Opt Soc Am A Opt Image Sci Vis 19:1162-71. 2002
    ..The errors in quantitative and localization accuracies depend on the size and location of the clear regions...
  3. ncbi request reprint Multiwavelength three-dimensional near-infrared tomography of the breast: initial simulation, phantom, and clinical results
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 42:135-45. 2003
    ....
  4. ncbi request reprint Effects of refractive index on near-infrared tomography of the breast
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, New Hampshire 03755 8000, USA
    Appl Opt 44:1870-8. 2005
    ..The results suggest that provided the refractive index of breast tissue is approximately 1.3-1.4, their exclusion will have minimal effect on the reconstructed images...
  5. ncbi request reprint Image reconstruction of effective Mie scattering parameters of breast tissue in vivo with near-infrared tomography
    Xin Wang
    Dartmouth College, Department of Physics and Astronomy, Hanover, New Hampshire 03755, USA
    J Biomed Opt 11:041106. 2006
    ....
  6. ncbi request reprint In vivo hemoglobin and water concentrations, oxygen saturation, and scattering estimates from near-infrared breast tomography using spectral reconstruction
    Subhadra Srinivasan
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Acad Radiol 13:195-202. 2006
    ....
  7. ncbi request reprint Spectrally constrained chromophore and scattering near-infrared tomography provides quantitative and robust reconstruction
    Subhadra Srinivasan
    Department of Biomedical Engineering, Thayer School of Engineering, Dartmouth College, P O Box 8000, Hanover, New Hampshire 03755, USA
    Appl Opt 44:1858-69. 2005
    ..Accurate quantification was obtained with a mean error of 7.7% for oxygen saturation and 6.2% for total hemoglobin, with minimal cross talk between different parameters...
  8. ncbi request reprint Spectral priors improve near-infrared diffuse tomography more than spatial priors
    Ben Brooksby
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, New Hampshire 03755, USA
    Opt Lett 30:1968-70. 2005
    ..When both spatial and spectral priors were applied in a healthy volunteer, glandular tissue showed a higher [Hb(T)], water fraction, and scattering power compared to adipose tissue...
  9. pmc Imaging breast adipose and fibroglandular tissue molecular signatures by using hybrid MRI-guided near-infrared spectral tomography
    Ben Brooksby
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
    Proc Natl Acad Sci U S A 103:8828-33. 2006
    ..Combined MR and near-infrared tomography provides fundamental molecular information about these tissue types with resolution governed by MR T1 images...
  10. ncbi request reprint Characterization of hemoglobin, water, and NIR scattering in breast tissue: analysis of intersubject variability and menstrual cycle changes
    Brian W Pogue
    Thayer School of Engineering, Dartmouth College, 800 Cummings Hall, Hanover, New Hampshire 03755, USA
    J Biomed Opt 9:541-52. 2004
    ....
  11. pmc Implementation of a computationally efficient least-squares algorithm for highly under-determined three-dimensional diffuse optical tomography problems
    Phaneendra K Yalavarthy
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Med Phys 35:1682-97. 2008
    ..Use of these new alternative forms becomes effective when the ratio of the number of imaging property parameters exceeds the number of measurements by a factor greater than 2...
  12. ncbi request reprint Breast deformation modelling for image reconstruction in near infrared optical tomography
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Phys Med Biol 49:1131-45. 2004
    ..Finally, assuming a non-deformed breast shape for image reconstruction is shown to lead to poor quality images since the geometry of the breast is greatly altered, whereas using the correct deformed geometry produces the best images...
  13. ncbi request reprint Combining near-infrared tomography and magnetic resonance imaging to study in vivo breast tissue: implementation of a Laplacian-type regularization to incorporate magnetic resonance structure
    Ben Brooksby
    Dartmouth College, Thayer School of Engineering, 8000 Cummings Hall, Hanover, New Hampshire 03755, USA
    J Biomed Opt 10:051504. 2005
    ..This approach is expected to improve recovery of abnormalities within the breast, as the inclusion of structural information increases the accuracy of recovery of embedded heterogeneities, at least in phantom studies...
  14. ncbi request reprint Near-infrared characterization of breast tumors in vivo using spectrally-constrained reconstruction
    Subhadra Srinivasan
    Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire 03755, USA
    Technol Cancer Res Treat 4:513-26. 2005
    ..These changes represent potential diagnostic indicators, which can be assessed to characterize breast tumors...
  15. ncbi request reprint Receiver operating characteristic and location analysis of simulated near-infrared tomography images
    Xiaomei Song
    Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire 03755, USA
    J Biomed Opt 12:054013. 2007
    ..Interobserver variance performance in detecting objects in these images was low, suggesting that because of the low spatial resolution, detection tasks with NIR tomography is likely consistent between human observers...
  16. ncbi request reprint Image analysis methods for diffuse optical tomography
    Brian W Pogue
    Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire 03755, USA
    J Biomed Opt 11:33001. 2006
    ..Each of these three major areas of image interpretation and analysis are reviewed in the context of medical imaging as well as how they are used to quantify the performance of diffuse optical imaging of tissue...
  17. ncbi request reprint Improved quantification of small objects in near-infrared diffuse optical tomography
    Subhadra Srinivasan
    Dartmouth College, Thayer School of Engineering, Hanover, NH 03755, USA
    J Biomed Opt 9:1161-71. 2004
    ..The algorithm is successfully applied to clinical data from a subject with a breast abnormality to yield quantitatively increased absorption coefficients, which enhances the contrast to 3.8 compared to 1.23 previously...
  18. ncbi request reprint Automated region detection based on the contrast-to-noise ratio in near-infrared tomography
    Xiaomei Song
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 43:1053-62. 2004
    ..4. A new linear convolution method of CNR calculation was developed for automated region of interest (ROI) detection...
  19. ncbi request reprint Magnetic-resonance-imaging-coupled broadband near-infrared tomography system for small animal brain studies
    Heng Xu
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 44:2177-88. 2005
    ....
  20. ncbi request reprint Image-guided optical spectroscopy provides molecular-specific information in vivo: MRI-guided spectroscopy of breast cancer hemoglobin, water, and scatterer size
    Colin M Carpenter
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Opt Lett 32:933-5. 2007
    ..Integration of molecular spectroscopy into standard clinical MRI can be achieved with this approach to spectral tomography...
  21. ncbi request reprint Video-rate near-infrared optical tomography using spectrally encoded parallel light delivery
    Daqing Piao
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Opt Lett 30:2593-5. 2005
    ..35 mm diameter inclusion with an absorption coefficient of 0.01 mm(-1) and a reduced scattering coefficient of 1.5 mm(-1) that is moving along a circular path inside a 1% Intralipid solution...
  22. ncbi request reprint Excitation patterns in three-dimensional electrical impedance tomography
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Physiol Meas 26:S185-97. 2005
    ..However, in terms of quantitative imaging an excitation pattern where all electrode layers are in phase produces better results...
  23. ncbi request reprint Absorption and scattering imaging of tissue with steady-state second-differential spectral-analysis tomography
    Heng Xu
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Opt Lett 29:2043-5. 2004
    ..The steady-state broadband CCD system has the potential to provide accurate chromophore imaging without the technological complexity of time- or frequency-domain systems...
  24. ncbi request reprint The effects of internal refractive index variation in near-infrared optical tomography: a finite element modelling approach
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Phys Med Biol 48:2713-27. 2003
    ....
  25. ncbi request reprint Subsurface diffuse optical tomography can localize absorber and fluorescent objects but recovered image sensitivity is nonlinear with depth
    Dax S Kepshire
    Thayer School of Engineering, Dartmouth College, New Hampshire 03755, USA
    Appl Opt 46:1669-78. 2007
    ..However, increases in tissue curvature and/or the addition of prior information are expected to improve the linearity of the response. The potential for this type of imaging technique to serve as a surgical guide is highlighted...
  26. pmc Tissue drug concentration determines whether fluorescence or absorption measurements are more sensitive in diffuse optical tomography of exogenous contrast agents
    Scott C Davis
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Appl Opt 48:D262-72. 2009
    ..Specifically, fluorescence measurements are favorable if background drug concentrations are below 135-200 nM for LuTex and 25-50 nM for ICG, while absorption measurements are more sensitive above these ranges...
  27. pmc Magnetic resonance-coupled fluorescence tomography scanner for molecular imaging of tissue
    Scott C Davis
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Rev Sci Instrum 79:064302. 2008
    ..A pilot murine study using an orthotopic glioma tumor model demonstrates optical-MRI imaging of an epidermal growth factor receptor targeted fluorescent probe in vivo...
  28. pmc Fluorescence tomography characterization for sub-surface imaging with protoporphyrin IX
    Dax Kepshire
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Opt Express 16:8581-93. 2008
    ....
  29. pmc A microcomputed tomography guided fluorescence tomography system for small animal molecular imaging
    Dax Kepshire
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Rev Sci Instrum 80:043701. 2009
    ..This multimodality imaging system will have a wide range of applications in preclinical cancer research ranging from studies of the tumor microenvironment and treatment efficacy for emerging cancer therapeutics...
  30. ncbi request reprint Spectral derivative based image reconstruction provides inherent insensitivity to coupling and geometric errors
    Heng Xu
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Opt Lett 30:2912-4. 2005
    ....
  31. pmc Interpreting hemoglobin and water concentration, oxygen saturation, and scattering measured in vivo by near-infrared breast tomography
    Subhadra Srinivasan
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Proc Natl Acad Sci U S A 100:12349-54. 2003
    ..These breast constituents vary significantly between individuals and can be altered because of changes in breast physiology or pathological state...
  32. pmc Automatic exposure control and estimation of effective system noise in diffuse fluorescence tomography
    Dax L Kepshire
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755, USA
    Opt Express 17:23272-83. 2009
    ..This fluorophore has very low fluorescence yield, but high biological relevance for tumor imaging, given that it is produced in the mitochondria, and upregulated in many tumor types...
  33. pmc Fast segmentation and high-quality three-dimensional volume mesh creation from medical images for diffuse optical tomography
    Michael Jermyn
    Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire 03755, USA
    J Biomed Opt 18:86007. 2013
    ..These capabilities represent a significant step toward enabling translational multimodal NIR research for both expert and nonexpert users in an open-source platform...
  34. pmc Early-photon fluorescence tomography: spatial resolution improvements and noise stability considerations
    Frederic Leblond
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover New Hampshire 03755, USA
    J Opt Soc Am A Opt Image Sci Vis 26:1444-57. 2009
    ..5 to 2.5 mm) separated by less than 1.5 mm...
  35. ncbi request reprint Electrical impedance tomography of human brain function using reconstruction algorithms based on the finite element method
    Andrew P Bagshaw
    Department of Clinical Neurophysiology, University College London, UK
    Neuroimage 20:752-64. 2003
    ....
  36. ncbi request reprint Weight-matrix structured regularization provides optimal generalized least-squares estimate in diffuse optical tomography
    Phaneendra K Yalavarthy
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Med Phys 34:2085-98. 2007
    ....
  37. pmc Implicit and explicit prior information in near-infrared spectral imaging: accuracy, quantification and diagnostic value
    Brian W Pogue
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Philos Trans A Math Phys Eng Sci 369:4531-57. 2011
    ..Most beneficial inclusion of prior information has been in the inversion/reconstruction process, because it solves the mathematical intractability. However, it is not clear that this is always the most beneficial stage...
  38. ncbi request reprint Spectrally resolved bioluminescence optical tomography
    Hamid Dehghani
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Opt Lett 31:365-7. 2006
    ..The location of the internal bioluminescence is obtained with 1 mm accuracy. Further, the amplitude of the reconstructed source is proportional to the actual bioluminescence intensity...
  39. pmc Multiple-gate time domain diffuse fluorescence tomography allows more sparse tissue sampling without compromising image quality
    Robert W Holt
    Thayer School of Engineering, Dartmouth College, Hanover, New Hampshire 03755, USA
    Opt Lett 37:2559-61. 2012
    ....
  40. ncbi request reprint Near-infrared imaging in the small animal brain: optimization of fiber positions
    Heng Xu
    Dartmouth College, Thayer School of Engineering, Hanover, New Hampshire 03755, USA
    J Biomed Opt 8:102-10. 2003
    ..Practical space limitation considerations favor the one-sided fiber array geometry in the case where the NIR acquisition is expected to occur simultaneously with MRI...
  41. ncbi request reprint A novel data calibration scheme for electrical impedance tomography
    Nirmal K Soni
    Thayer School of Engineering, Dartmouth College, 8000 Cummings Hall, Hanover, NH 03755 8000, USA
    Physiol Meas 24:421-35. 2003
    ....
  42. ncbi request reprint CT contrast predicts pancreatic cancer treatment response to verteporfin-based photodynamic therapy
    Michael Jermyn
    Thayer School of Engineering, Dartmouth College, Hanover, NH 03755, USA
    Phys Med Biol 59:1911-21. 2014
    ..This study is the first to show that contrast CT provides needed surrogate dosimetry information to predict treatment response in a manner which uses standard-of-care clinical images, rather than invasive dosimetry methods...
  43. ncbi request reprint Optical tomography of a realistic neonatal head phantom
    Adam Gibson
    Department of Medical Physics and Bioengineering, University College London, 11 20 Capper Street, London WC1E 6JA
    Appl Opt 42:3109-16. 2003
    ..The head-shaped mesh performed slightly better than the spherical mesh, particularly when the absorption of the central region of the phantom was increased...
  44. doi request reprint Diffuse optical imaging
    Adam Gibson
    Department of Medical Physics and Bioengineering, University College London, London WC1E 6BT, UK
    Philos Trans A Math Phys Eng Sci 367:3055-72. 2009
    ..We aim to review the state of the art of optical imaging...
  45. ncbi request reprint Time resolved optical tomography of the human forearm
    E M Hillman
    Department of Medical Physics and Bioengineering, University College London, UK
    Phys Med Biol 46:1117-30. 2001
    ....
  46. ncbi request reprint Finite element implementation of Maxwell's equations for image reconstruction in electrical impedance tomography
    Nirmal K Soni
    Philips Medical Systems, Cleveland, OH 44143, USA
    IEEE Trans Med Imaging 25:55-61. 2006
    ..The results show that scalar/vector potential reconstruction produces images which are essentially indistinguishable from a Laplace algorithm for frequencies below 1 MHz but superior at frequencies reaching 10 MHz...
  47. ncbi request reprint Contrast-detail analysis characterizing diffuse optical fluorescence tomography image reconstruction
    Scott C Davis
    J Biomed Opt 10:050501. 2005
    ..Contrast-detail analysis using human detection of lower contrast limits provides fundamentally important information about the performance of reconstruction algorithms, and can be used to compare imaging performance of different systems...
  48. ncbi request reprint Endoscopic, rapid near-infrared optical tomography
    Daqing Piao
    School of Electrical and Computer Engineering, Oklahoma State University, Stillwater, Oklahoma, USA
    Opt Lett 31:2876-8. 2006
    ..This novel approach provides the key feasibility studies to allow this blood-based contrast imaging technology to be attempted in detection of cancer in internal organs via endoscopic interrogation...
  49. ncbi request reprint Numerical modelling errors in electrical impedance tomography
    Hamid Dehghani
    School of Physics, University of Exeter, UK
    Physiol Meas 28:S45-55. 2007
    ....
  50. pmc Retinotopic mapping of adult human visual cortex with high-density diffuse optical tomography
    Benjamin W Zeff
    Department of Radiology, Washington University School of Medicine, St Louis, MO 63110, USA
    Proc Natl Acad Sci U S A 104:12169-74. 2007
    ..These results demonstrate that high-density DOT is a practical and powerful tool for mapping function in the human cortex...