A novel 3D photoacoustic imaging technique is experimentally demonstrated using a 64×64 element bias-sensitive crossed-electrode relaxor array. This allows for large 2D arrays to receive across all elements while minimal channel counts. Hadamard-bias patterns are applied column electrodes signals measured from row electrodes. Photoacoustic crossed-wire phantom in an intralipid scattering medium. The Hadamard-bias-encoded scheme showed signal-to-noise (SNR) of 25.3 dB, the single-column...

To understand the pathogenic processes for infectious bacteria, appropriate research tools are required replicating and characterizing infections. Fluorescence bioluminescence imaging have primarily been used to image infections in animal models, but optical scattering tissue significantly limits depth resolution. Photoacoustic imaging, which has improved depth-to-resolution ratio compared conventional could be useful visualizing melA-expressing bacteria since melA is a bacterial tyrosinase...

A combined photoacoustic-ultrasound (PAUS) tomography system is introduced using ring-array and novel aperture encoding schemes. The ultrasound subsystem able to achieve diffraction limited half-wavelength isotropic in-plane spatial resolution unlike previous systems. S-sequence improves signal-to-noise ratio (SNR) for the (UST) subsystem. We measured an average of [Formula: see text] UST a photoacoustic tomography. were measure SNR improvement tissue-mimicking phantoms, we displayed...

A novel reconstruction technique based on delay-and-sum ultrasound tomography algorithms is introduced. This enables tomographic systems to produce compressibility- and density-weighted images (D-WI) for spherically symmetric scatterers. The efficacy of this was demonstrated with simulation phantom experiments. Separation between a dense wire target compressible thread within quantified, showing an increased signal the D-WIs. suppression background scatter in D-WIs also quantified....

Aspects of spinal bone marrow fat to water ratio (FWR) quantification with magnetic resonance spectroscopy (MRS) at 3 T were examined in this work. A Point RESolved Spectroscopy (PRESS) sequence TE = 40 ms and 70 was employed obtain spectra from L3 T7 vertebrae twenty healthy volunteers within the age range 21–50 years (8 female, 12 male); measurements C4 vertebra obtained 19 volunteers. The used determine FWR T2 values. Spectra fitted yield areas for peak (≈1.3 ppm), (≈4.7 ppm) olefinic...

We compare scanned-mosaicking and blanket illumination schemes for wide-field photoacoustic tomography with potential applications to breast imaging. For each illumination, a locally high-SNR image patch is reconstructed then mosaicked patches from other illuminations. Because the beam not diffused over entire area, fluence of can be maximized, therefore maximizing signal generated. Moreover, imaging potentially still done fast enough within breath-hold. A Monte Carlo simulation as function...

An ultrasound tomography (UST) system was used to image scattering anisotropy in phantom experiments. This visualized as vector fields with arrows corresponding the principal angle of each pixel. UST a ring-array allows for large range transmit and receive combinations, producing real-time acquisition maps unachievable previous single element linear array studies. Resolution measured be [Formula: see text], averaged over seven different placements within transducer's field-of-view. Vector...

Recently, ℓ1-norm based reconstruction approaches have been used with linear array systems to improve photoacoustic resolution and demonstrate undersampled imaging when there is sufficient sparsity in some domain. However, such yet beat the half-wavelength limit. In this paper, ability diffraction limit demonstrated using a 5 MHz ring tomography system approaches. We image wire targets at ≈2−3cm depth both intralipid scattering solution water. The minimum observable separation was estimated...

Antibiotic drug resistance is a major worldwide issue. Development of new therapies against pathogenic bacteria requires appropriate research tools for replicating and characterizing infections. Previously fluorescence bioluminescence modalities have been used to image infectious burden in animal models but scattering significantly limits imaging depth resolution. We hypothesize that photoacoustic imaging, which has improved depth-toresolution ratio, could be useful visualizing...

Previously we described the potential for multiple illumination photoacoustic tomography to provide quantitative reconstructions, however this work used only simulated data. We have developed a custom photoacoustic-ultrasound system capable of illuminations and parallel acquisition from 256 element 5 MHz transducer ring array with 8-cm diameter. The scheme uses free-space light delivery geometry where rotational stage scans pulsed laser beam onto different incident locations around sample....

An optimal genetically-encoded probe for photoacoustic (PA) imaging should exhibit high optical absorption, low fluorescence quantum yield, and an absorption maxima within the near-infrared (NIR) window. One promising candidate is a newly engineered chromoprotein (CP), designated dark small ultra-red fluorescent protein (dsmURFP), which based on cyanobacterial phycobiliprotein. To optimize dsmURFP characteristics PA imaging, we have developed directed evolution method to iteratively screen...

A reflection-mode ultrasound scattering tomography system is introduced that capable of in-plane isotropic half-wavelength diffraction-limited resolution. By implementing an S-Sequence aperture encoding scheme, the Signal to Noise Ratio (SNR) improved. Resolution and SNR improvement were both measured experimentally with a ring array transducer.