IEEE J Sel Top Quantum Electron
· 2026 · PMID 42088446
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We propose an inverse design framework for metasurfaces that achieves highly uniform two-dimensional intensity profiles across an on-demand shape. The optimization objective is formulated to enhance overall projection ef...We propose an inverse design framework for metasurfaces that achieves highly uniform two-dimensional intensity profiles across an on-demand shape. The optimization objective is formulated to enhance overall projection efficiency via the adjoint method, while a regularization term penalizes local deviations in field amplitude to suppress intensity non-uniformity. The regularization weight is adaptively tuned based on the current non-uniformity, enabling stable and efficient optimization. Compared with the widely used mean squared error (MSE) objective, our method yields superior performance in both intensity fidelity and uniformity. We also extend our framework to handle realistic Gaussian beam illumination by biasing the library. This framework utilizes the Finite Element Method (FEM) for surrogate modeling and full-wave Finite-Difference Time-Domain (FDTD) simulations for rigorous verification. Simulation results confirm the effectiveness of our approach for generating high-quality, uniform field patterns.
Zhao M, Dickstein L, Nadig AS
… +8 more, Zhou W, Aparanji S, Estrada HG, Liu SJ, Zhou T, Yang W, Lord A, Srinivasan VJ
IEEE J Sel Top Quantum Electron
· 2025 · PMID 41822112
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Light speckle fluctuations provide a means for noninvasive measurements of cerebral blood flow index (CBFi). While conventional Diffuse Correlation Spectroscopy (DCS) quantifies these fluctuations to provide marginal bra...Light speckle fluctuations provide a means for noninvasive measurements of cerebral blood flow index (CBFi). While conventional Diffuse Correlation Spectroscopy (DCS) quantifies these fluctuations to provide marginal brain sensitivity for CBFi in adult humans, new techniques have emerged to improve diffuse light throughput and brain sensitivity. Here we further optimize one such approach, interferometric diffusing wave spectroscopy (iDWS), with respect to the number of independent channels, camera duty cycle and full well capacity, incident laser power, noise and artifact mitigation, and data processing. We build the system on a cart and define conditions for stable operation. We show pulsatile CBFi monitoring at 4-4.5 cm source-collector separation in adults with moderate pigmentation (Fitzpatrick 4). We also report preliminary clinical measurements of patient CBFi in the Neuro Intensive Care Unit (Neuro ICU). These results push the boundaries of iDWS CBFi monitoring performance beyond previous reports.
IEEE J Sel Top Quantum Electron
· 2026 · PMID 41809093
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Nonlinear microscopy enables label-free imaging by deriving contrast from the intrinsic spectroscopic responses of specimens, thereby offering a valuable tool for biomedical applications. Often, clinical imaging systems...Nonlinear microscopy enables label-free imaging by deriving contrast from the intrinsic spectroscopic responses of specimens, thereby offering a valuable tool for biomedical applications. Often, clinical imaging systems implement either multiphoton or vibrational contrast, not both. Consequently, most clinically deployed label-free nonlinear microscopes lack a robust, complementary contrast palette suitable for investigating the morphofunctional features of heterogeneous specimens. This deficiency limits not only the analytical capabilities of the nonlinear microscope but also its diagnostic utility. A main reason for this disregard is that the various imaging modalities impose distinct and stringent requirements on the excitation source and the detection chain. In this contribution, we propose a strategy that targets multiphoton and vibrational contrasts to achieve a robust, complementary contrast palette. The approach emerges from a systematic investigation of readout schemes and provides engineering criteria to tailor the detection chain and thus maximize quantitative performance. In concert with this detection strategy, we present a compact laser source that drives vibrational coherences while simultaneously exciting multiphoton signals. We validate the resulting imaging platform using two rodent case studies: one involving a naturally occurring metastatic cancer in a mouse and another relying on an allogeneic mammary cancer model in a rat. Owing to its dimensions, cost, and versatility, we anticipate that this biophotonics tool will readily find its way into clinical applications.
IEEE J Sel Top Quantum Electron
· 2026 · PMID 41552355
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We evaluated the microstructural and thermal stability of beef fat and lean meat tissue over 56 days of household frozen storage (-18°C) using Brillouin spectroscopy, Raman spectroscopy, Differential Scanning Calorimetry...We evaluated the microstructural and thermal stability of beef fat and lean meat tissue over 56 days of household frozen storage (-18°C) using Brillouin spectroscopy, Raman spectroscopy, Differential Scanning Calorimetry (DSC), and Fluorescence Lifetime Imaging Microscopy (FLIM). Mechanical stiffness represented by Brillouin shift values ( ) and Brillouin line FWHM values ( ), and thermal metrics ( ) of fat and lean meat samples remained within experimental uncertainty ( ) throughout storage. While Raman spectra showed minimal chemical contrast between tissue types, autofluorescence lifetime constants ( ) and Brillouin shifts enabled robust, label-free mechanical discrimination of fat versus lean meat domains. Compression and acetone treatments confirmed the techniques' sensitivity. These results demonstrate that common home-freezing preserves beef tissue microstructure and fat thermal behavior over two months, and that combined optical and calorimetric methods offer a non-destructive framework for meat quality assessment.
Hasan MZ, Yan J, Sarker S
… +2 more, Saha PS, Zhu C
IEEE J Sel Top Quantum Electron
· 2026 · PMID 41541596
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Most tissue optical spectroscopy platforms use a fiber probe for light delivery and collection, while the inconsistent probe-sample contact could induce significant distortions in the measured optical signals, which cons...Most tissue optical spectroscopy platforms use a fiber probe for light delivery and collection, while the inconsistent probe-sample contact could induce significant distortions in the measured optical signals, which consequently bring analysis errors. Moreover, it will be practically difficult to use a fiber probe for measurements in some cases such as oral cancer investigations using small animal models. To address the critical challenge, we report a portable, lens-based, optical spectroscopy device capable of quantifying key vascular and metabolic parameters without probe-sample contact. We combined lenses based diffuse reflectance and fluorescence spectroscopy into one portable platform to enable multi-parametric functional characterizations of orthotopic tongue cancer models . We also implemented easy-to-use spectroscopic algorithms with the system for rapid quantification of the key metabolic and vascular parameters on biological tissue models. We then demonstrated our non-contact optical spectroscopy on tissue-mimicking phantoms and mouse tongue tumor models. Our phantom and animal studies showed that our non-contact optical spectroscopy, along with spectroscopic algorithms, could quantify the major metabolic and vascular parameters on tongue tumors with high accuracy. We also captured the diverse metabolic and vascular phenotypes of tongue tumors with different radiation sensitivity. Our new optical spectroscopy implemented with easy-to-use spectroscopic algorithms will provide a non-contact way for rapid and systematic characterizations of biological tissue metabolism and vascular microenvironment , which may significantly advance head and neck cancer research in the future.
Howard AC, Kim B, Carlton L
… +4 more, Yücel MA, Liu B, Boas DA, Cheng X
IEEE J Sel Top Quantum Electron
· 2025 · PMID 40842636
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Speckle contrast optical spectroscopy (SCOS) is an optical technique capable of measuring human cerebral blood flow and brain function non-invasively. Its tomographic extension, speckle contrast optical tomography (SCOT)...Speckle contrast optical spectroscopy (SCOS) is an optical technique capable of measuring human cerebral blood flow and brain function non-invasively. Its tomographic extension, speckle contrast optical tomography (SCOT), can provide blood flow variation maps with measurements using overlapping source-detector channel pairs. Linearity is often assumed in most image reconstruction methods, but non-linearity could exist in the relations between measured signals and blood flow variations. We have constructed a forward model for SCOT using the Rytov approximation to solve the correlation diffusion equation and compared it with the first Born approximation as well as the more accurate, but computationally expensive Monte Carlo simulation approach. We have shown that the results obtained using the Rytov approximation are in good agreement with the Monte Carlo simulations, while the first Born approximation deviates from the other two methods for large blood flow variations. For instance, the first Born approximation breaks down at around 30% cerebral blood flow (CBF) changes within a volume of size 60 × 50 × 40 mm, therefore we recommend using the Rytov approximation above this threshold. We have shown that our defined blood flow index (BFi) measured in SCOT is linearly related to local CBF variations, thus the forward and inverse problems can be solved linearly using the sensitivity matrix approach. We have then demonstrated image reconstruction experimentally showing human brain activations using our recently developed high-density SCOS system. Our method guides experimental system design and data analysis for SCOT.
Robinson MB, Renna M, Otic N
… +4 more, Kierul OS, Muldoon A, Franceschini MA, Carp SA
IEEE J Sel Top Quantum Electron
· 2025 · PMID 40766943
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In this work, we present an enhanced diffuse correlation spectroscopy (DCS) method called pathlength-selective, interferometric DCS (PaLS-iDCS), which uses pathlength-specific coherent gain to improve both the sensitivit...In this work, we present an enhanced diffuse correlation spectroscopy (DCS) method called pathlength-selective, interferometric DCS (PaLS-iDCS), which uses pathlength-specific coherent gain to improve both the sensitivity to deep tissue hemodynamics and measurement SNR. Through interferometric detection, PaLS-iDCS can provide time-of-flight (ToF) specific blood flow information without the use of expensive time-tagging electronics and low-jitter detectors. The technique is compared to time-domain DCS (TD-DCS), another enhanced DCS method able to resolve photon ToF in tissue, through Monte Carlo simulation, phantom experiments, and human subject measurements. PaLS-iDCS consistently demonstrates improvements in SNR (>2x) for similar measurement conditions (same photon ToF), and the SNR improvements allow for measurements at extended photon ToFs, which have increased sensitivity to deep tissue hemodynamics (~50% increase). Further, like TD-DCS, PaLS-iDCS allows direct estimation of tissue optical properties from the sampled ToF distribution. This method offers a relatively straightforward way to allow DCS systems to make robust measurements of blood flow with greatly enhanced sensitivity to deep tissue hemodynamics without the need for time-resolved detection, enabling further applications of this non-invasive technology.
IEEE J Sel Top Quantum Electron
· 2023 · PMID 38327699
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myloid-Detection and imaging of amyloid-β plaques (Aβ) has been a focus in the field of neurodegeneration (ND) due to the high correlation with Parkinson's and Alzheimer's diseases. Here, a novel approach is being propos...myloid-Detection and imaging of amyloid-β plaques (Aβ) has been a focus in the field of neurodegeneration (ND) due to the high correlation with Parkinson's and Alzheimer's diseases. Here, a novel approach is being proposed and developed to induce and assess those diseases. Photodynamic therapy (PDT) is applied to the fruit fly as a model of systemic oxidative stress to induce rapid Aβ accumulation. Excised brains are evaluated by Brillouin-Raman spectroscopy and microscopy with UV surface emissions (MUSE) to interrogate physical property changes due to fixation and high-dose PDT. MUSE reveals reasonable autofluorescence in the spectral range of Aβ, particularly for females, with increased signal once stained. A presence of significant mechanical changes in fresh brains treated with PDT compared to healthy controls is revealed using Brillouin spectroscopy. Aβ plaque presence was confirmed with confocal analysis, with female PDT flies yielding nearly four-fold the mean intensity of controls, thus marking PDT as a potential neurodegenerative disease model. MUSE may serve as a viable early screening method for Aβ presence and quantification in a research setting. This reduces the time for sample preparation and drastically decreases the cost of Aβ quantification.
Tehrani KF, Park J, Chaney EJ
… +2 more, Tu H, Boppart SA
IEEE J Sel Top Quantum Electron
· 2023 · PMID 37193134
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Hematoxylin and eosin (H&E) staining, the century-old technique, has been the gold standard tool for pathologists to detect anomalies in tissues and diseases such as cancer. H&E staining is a cumbersome, time-consuming p...Hematoxylin and eosin (H&E) staining, the century-old technique, has been the gold standard tool for pathologists to detect anomalies in tissues and diseases such as cancer. H&E staining is a cumbersome, time-consuming process that delays and wastes precious minutes during an intraoperative diagnosis. However, even in the modern era, real-time label-free imaging techniques such as simultaneous label-free autofluorescence multiharmonic (SLAM) microscopy have delivered several more layers of information to characterize a tissue with high precision. Still, they have yet to translate to the clinic. The slow translation rate can be attributed to the lack of direct comparisons between the old and new techniques. Our approach to solving this problem is to: 1) reduce dimensions by pre-sectioning the tissue in 500 μm slices, and 2) produce fiducial laser markings which appear in both SLAM and histological imaging. High peak-power femtosecond laser pulses enable ablation in a controlled and contained manner. We perform laser marking on a grid of points encompassing the SLAM region of interest. We optimize laser power, numerical aperture, and timing to produce axially extended marking, hence multilayered fiducial markers, with minimal damage to the surrounding tissues. We performed this co-registration over an area of 3 × 3 mm of freshly excised mouse kidney and intestine, followed by standard H&E staining. Reduced dimensionality and the use of laser markings provided a comparison of the old and new techniques, giving a wealth of correlative information and elevating the potential of translating nonlinear microscopy to the clinic for rapid pathological assessment.
IEEE J Sel Top Quantum Electron
· 2023 · PMID 36466144
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This study explores UV light induced fluorescence from blood vessels for indicating successful infrared laser sealing of vascular tissues. A light emitting diode (LED) with center wavelength of 340 nm and 0.1 mW power wa...This study explores UV light induced fluorescence from blood vessels for indicating successful infrared laser sealing of vascular tissues. A light emitting diode (LED) with center wavelength of 340 nm and 0.1 mW power was used with a Y-shaped fiber bundle of seven 200-μm-core fibers. The central excitation fiber was connected to the LED, while the detection ring of six fibers was connected to a spectrometer. The fiber bundle was aligned with porcine renal arteries compressed between optical windows. Fluorescence was acquired before and after vessel sealing, with a 1470 nm laser for 5 s at 30 W (sealing, n = 10) or 5 W (control, n = 10). Signal increase in the 470-520 nm spectrum was correlated with vessel burst pressures (BP). Integrated fluorescence increased 71 ± 25% at 30 W vs. 19 ± 14% at 5 W (p < 0.05), corresponding to a successful BP of 639 ± 189 mmHg vs. failed seal BP of 39 ± 41 mmHg (p < 0.05). Real-time measurements showed a gradual increase in fluorescence with the signal reaching a plateau at 3-4 s, indicating that shorter seal times are possible. The increase in fluorescence signal during laser vessel sealing may provide a non-destructive, real-time, optical method for indicating hemostatic seals.
Hasan MZ, Yan J, Yi Z
… +3 more, Korfhage MO, Tong S, Zhu C
IEEE J Sel Top Quantum Electron
· 2023 · PMID 36341280
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OBJECTIVE: Real-time monitoring of nanoparticle delivery in biological models is essential to optimize nanoparticle-mediated therapies. However, few techniques are available for convenient real-time monitoring of nanopar...OBJECTIVE: Real-time monitoring of nanoparticle delivery in biological models is essential to optimize nanoparticle-mediated therapies. However, few techniques are available for convenient real-time monitoring of nanoparticle concentrations in tissue samples. This work reported novel optical spectroscopic approaches for low-cost point-of-care real-time quantification of nanoparticle concentrations in biological tissue samples. METHODS: Fiber probe measured diffuse reflectance can be described with a simple analytical model by introducing an explicit dependence on the reduced scattering coefficient. Relying on this, the changes on the inverse of diffuse reflectance are proportional to absorption change when the scattering perturbation is negligible. We developed this model with proper wavelength pairs and implemented it with both a standard optical spectroscopy platform and a low-cost compact spectroscopy device for near real-time quantification of nanoparticle concentrations in biological tissue models. RESULTS: Both tissue-mimicking phantom and tissue sample studies showed that our optical spectroscopic techniques could quantify nanoparticle concentrations in near real-time with high accuracies (less than 5% error) using only a pair of narrow wavelengths (530 nm and 630 nm). CONCLUSION: Novel low-cost point-of-care optical spectroscopic techniques were demonstrated for rapid accurate quantification of nanoparticle concentrations in tissue-mimicking medium and tissue samples using optical signals measured at a pair of narrow wavelengths. SIGNIFICANCE: Our methods will potentially facilitate real-time monitoring of nanoparticle delivery in biological models using low-cost point-of-care optical spectroscopy platforms, which will significantly advance nanomedicine in cancer research.
Shutov AD, Harrington JT, Zhu H
… +3 more, Wang DW, Zhang D, Yakovlev VV
IEEE J Sel Top Quantum Electron
· 2021 · PMID 35756884
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Raman spectroscopy provides a non-invasive, chemically-specific optical imaging of biological objects without relying on endogenous labels. Nonlinear Raman spectroscopy allows non-invasive imaging at much faster speed wi...Raman spectroscopy provides a non-invasive, chemically-specific optical imaging of biological objects without relying on endogenous labels. Nonlinear Raman spectroscopy allows non-invasive imaging at much faster speed with an improved spatial resolution and axial sectioning capability. In this report we propose a novel use of nonlinear Raman spectroscopy as a sensor of local nano-environment. Time-resolved coherent anti-Stokes Raman spectrograms are found to be sensitive to small variations of local structural changes, which are not normally observed using conventional Raman spectroscopy.
Mendez CB, Gonda A, Shah JV
… +8 more, Siebert JN, Zhao X, He S, Riman RE, Tan MC, Moghe PV, Ganapathy V, Pierce MC
IEEE J Sel Top Quantum Electron
· 2021 · PMID 36710719
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Fluorescence-guided surgery (FGS) is an emerging technique for tissue visualization during surgical procedures. Structures of interest are labeled with exogenous probes whose fluorescent emissions are acquired and viewed...Fluorescence-guided surgery (FGS) is an emerging technique for tissue visualization during surgical procedures. Structures of interest are labeled with exogenous probes whose fluorescent emissions are acquired and viewed in real-time with optical imaging systems. This study investigated rare-earth-doped albumin-encapsulated nanocomposites (REANCs) as short-wave infrared emitting contrast agents for FGS. Experiments were conducted using an animal model of 4T1 breast cancer. The signal-to-background ratio (SBR) obtained with REANCs was compared to values obtained using indocyanine green (ICG), a near-infrared dye used in clinical practice. Prior to resection, the SBR for tumors following intratumoral administration of REANCs was significantly higher than for tumors injected with ICG. Following FGS, evaluation of fluorescence intensity levels in excised tumors and at the surgical bed demonstrated higher contrast between tissues at these sites with REANC contrast than ICG. REANCs also demonstrated excellent photostability over 2 hours of continuous illumination, as well as the ability to perform FGS under ambient lighting, establishing these nanocomposites as a promising contrast agent for FGS applications.
IEEE J Sel Top Quantum Electron
· 2021 · PMID 34177217
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We propose and demonstrate, first on simulated spectra and then experimentally, a novel approach to correct the undesired background distortions in the Brillouin spectra caused by molecular filter's absorption, fluoresce...We propose and demonstrate, first on simulated spectra and then experimentally, a novel approach to correct the undesired background distortions in the Brillouin spectra caused by molecular filter's absorption, fluorescent emission, ambient room light or any other constant contaminant. The developed multi-wavelength excitation Brillouin spectroscopy method computationally reconstructs the pure Brillouin component of the signal from multiple Brillouin spectra acquired using different excitation wavelengths. By removing the baseline distortions, the approach improves the goodness of fit of the Brillouin peaks, enabling accurate Brillouin shift and linewidth measurements from a wide range of challenging samples. In the present report, we explain the principle behind the method on a set of simulated spectra and present experimental application on an intentionally strongly-distorted spectrum. Utilizing the multi-excitation Brillouin spectroscopy approach, we successfully reconstruct Brillouin spectra of a highly-scattering sample, initially rendered not analyzable by excessive iodine absorption and contamination by out-of-focus light.
IEEE J Sel Top Quantum Electron
· 2021 · PMID 34054285
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Cancer is among the leading cause of death around the world, causing close to 10 million deaths each year. Significant efforts have been devoted to developing novel technologies that can detect and treat cancer early and...Cancer is among the leading cause of death around the world, causing close to 10 million deaths each year. Significant efforts have been devoted to developing novel technologies that can detect and treat cancer early and effectively to reduce cancer recurrences, treatment costs, and mortality. Gold nanoparticles (GNP) have been given particular attention for its use with photo-induced hyperthermia coupled with novel immunotherapy methods to provide a new platform for highly selective and less invasive cancer treatment. Among the various GNP platforms, gold nanostars (GNS) have a unique star-shaped geometric structure that allows superior light absorption and photothermal heating. This photothermal effect have also been found to amplify the anti-tumor immune response and can be exploited with adjuvant treatments using immune checkpoint inhibitors. This combination treatment known as Synergistic Immuno Photo Nanotherapy (SYMPHONY) has been shown to reverse tumor-mediated immunosuppression and has led to effective and long-lasting immunity against not only primary tumors but also cancer metastasis. This overview highlights the development and applications of GNS-mediated therapy developed in our laboratory for cancer treatment. This paper also presents recent results of experimental studies to illustrate the superior performance of GNS for photothermal treatment applications.
Meena GG, Wright JG, Hawkins AR
… +1 more, Schmidt H
IEEE J Sel Top Quantum Electron
· 2021 · PMID 33994767
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High sensitivity and easy integration with microfabrication techniques has made silicon photonics one of the leading technologies used to build biosensors for diagnostic applications. Here we introduce a new silicon diox...High sensitivity and easy integration with microfabrication techniques has made silicon photonics one of the leading technologies used to build biosensors for diagnostic applications. Here we introduce a new silicon dioxide based optofluidic platform having a planar solid-core (SC) waveguide orthogonally intersecting a liquid-core (LC) waveguide with high refractive index ZnI2 salt solution as core. This enables both more uniform collection of particle fluorescence by the core mode and its propagation to an off-chip detector. This approach results in ultra-high sensitivity performance, demonstrated by achieving 8X enhancement in signal-to-noise ratio, a 45x increase in detection efficiency, and a 100x lower detection limit of 80 aM of fluorescent nanobeads. This represents a key step towards an ultrasensitive biosensor system for analyzing pathogens at clinical concentrations.
Zvietcovich F, Singh M, Ambekar YS
… +3 more, Aglyamov SR, Twa MD, Larin KV
IEEE J Sel Top Quantum Electron
· 2021 · PMID 33994766
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In optical coherence elastography (OCE), air-pulse stimulation has been widely used to produce propagation of mechanical waves for elastic characterization of tissues. In this paper, we propose the use of spatial deforma...In optical coherence elastography (OCE), air-pulse stimulation has been widely used to produce propagation of mechanical waves for elastic characterization of tissues. In this paper, we propose the use of spatial deformation spreading (SDS) on the surface of samples produced by air-pulse stimulation for the OCE of transverse isotropic tissues. Experiments in isotropic tissue-mimicking phantoms and anisotropic chicken tibialis muscle were conducted using a spectral-domain optical coherence tomography system synchronized with a confocal air-pulse stimulation. SDS measurements were compared with wave speeds values calculated at different propagation angles. We found an approximately linear relationship between shear wave speed and SDS in isotropic phantoms, which was confirmed with predictions made by the numerical integration of a wave propagation model. Experimental measurements in chicken muscle show a good agreement between SDS and surface wave speed taken along and across the axis of symmetry of the tissues, also called degree of anisotropy. In summary, these results demonstrated the capabilities of SDS produced by the air-pulse technique in measuring the shear elastic anisotropy of transverse isotropic tissues.
IEEE J Sel Top Quantum Electron
· 2021 · PMID 33746498
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Blood vessel burst pressures were simulated and predicted for sealing and cutting of vessels in a two-step process, using low (<25 W), medium (~100 W), and high (200 W) power lasers at a wavelength of 1470 nm. Monte Carl...Blood vessel burst pressures were simulated and predicted for sealing and cutting of vessels in a two-step process, using low (<25 W), medium (~100 W), and high (200 W) power lasers at a wavelength of 1470 nm. Monte Carlo optical transport, heat transfer, Arrhenius integral tissue damage simulations, and vessel pressure equations were utilized. The purpose of these studies was to first validate the numerical model by comparison with experimental results (for low and medium power) and then to use the model to simulate parameters that could not be experimentally tested (for high power). The goal was to reduce the large range of parameters (power, irradiation time, and linear beam dimensions) to be tested in future experiments, for achieving short vessel sealing/cutting times, minimal bifurcated seal zones (BSZ), and high vessel burst pressures. Blood vessels were compressed to 400 μm thickness. A wide range of linear beam profiles (1-5 mm widths and 8-9.5 mm lengths), incident powers (20-200 W) and clinically relevant irradiation times (0.5-5.0 s) were simulated and peak seal and cut temperatures as well as thermal seal zones, ablation zones, and BSZ computed. A simplistic mathematical expression was used to estimate vessel burst pressures based on seal width. Optimal low-power parameters were: 24W/5s/8×2mm (sealing) and 24W/5s/8×1mm (cutting), yielding a BSZ of 0.4 mm, corresponding to experimental burst pressures of ~450 mmHg. Optimal medium-power parameters were: 90W/1s/9.5×3mm (sealing) and 90W/1s/9.5×1mm (cutting), yielding a BSZ of 0.9 mm for burst pressures of ~1300 mmHg. Simulated only optimal high-power parameters were: 200W/0.5s/9×3 mm (sealing) and 200W/0.5s/9×1mm (cutting), yielding a BSZ of 0.9 mm and extrapolated to predict a seal strength of ~1300 mmHg. All lasers produced seal zones between 0.4-1.5 mm, corresponding to high vessel burst pressures of 300-1300 mmHg (well above normal systolic blood pressure of 120 mmHg). Higher laser powers enable shorter sealing/cutting times and higher vessel strengths.
Yang L, Park J, Marjanovic M
… +4 more, Chaney EJ, Spillman DR, Phillips H, Boppart SA
IEEE J Sel Top Quantum Electron
· 2021 · PMID 33746497
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Intraoperative imaging in surgical oncology can provide information about the tumor microenvironment as well as information about the tumor margin. Visualizing microstructural features and molecular and functional dynami...Intraoperative imaging in surgical oncology can provide information about the tumor microenvironment as well as information about the tumor margin. Visualizing microstructural features and molecular and functional dynamics may provide important diagnostic and prognostic information, especially when obtained in real-time at the point-of-procedure. A majority of current intraoperative optical techniques are based on the use of the labels, such as fluorescent dyes. However, these exogenous agents disrupt the natural microenvironment, perturb biological processes, and alter the endogenous optical signatures that cells and the microenvironment can provide. Portable nonlinear imaging systems have enabled intraoperative imaging for real-time detection and diagnosis of tissue. We review the development of a label-free multimodal nonlinear optical imaging technique that was adapted into a portable imaging system for intraoperative optical assessment of resected human breast tissue. New developments have applied this technology to assessing needle-biopsy specimens. Needle-biopsy procedures most always precede surgical resection and serve as the first sampling of suspicious masses for diagnosis. We demonstrate the diagnostic feasibility of imaging core needle-biopsy specimens during veterinary cancer surgeries. This intraoperative label-free multimodal nonlinear optical imaging technique can potentially provide a powerful tool to assist in cancer diagnosis at the point-of-procedure.