A5057474970- Photoacoustic and Ultrasonic Imaging
- Photodynamic Therapy Research Studies
- Advanced Fluorescence Microscopy Techniques
- Optical Imaging and Spectroscopy Techniques
- Optical Coherence Tomography Applications
- Biosensors and Analytical Detection
- 3D Printing in Biomedical Research
- Spectroscopy Techniques in Biomedical and Chemical Research
- Oral Health Pathology and Treatment
- Cell Image Analysis Techniques
- Viral Infectious Diseases and Gene Expression in Insects
- Mesenchymal stem cell research
- Salivary Gland Tumors Diagnosis and Treatment
- Image Processing Techniques and Applications
- Cellular Mechanics and Interactions
- AI in cancer detection
- Photonic and Optical Devices
- Head and Neck Cancer Studies
- Esophageal Cancer Research and Treatment
- Electrowetting and Microfluidic Technologies
- Cancer Research and Treatments
- Radiomics and Machine Learning in Medical Imaging
- Gut microbiota and health
- Diversity and Career in Medicine
- Laser Applications in Dentistry and Medicine
Texas A&M University
2015-2024
Chan Zuckerberg Initiative (United States)
2023-2024
Texas A&M Engineering Experiment Station
2023
Imaging Center
2021-2023
Texas College
2021
Mitchell Institute
2017-2019
Center For Remote Sensing (United States)
2017
The University of Texas at Austin
2006-2008
Lawrence Livermore National Laboratory
2007-2008
Bournville College
2006
This paper presents the use and characterization of an electrically focus tunable lens to perform axial scanning in a confocal microscope. Lateral resolution are characterized over >250 µm scan range. Confocal microscopy using optical is demonstrated epithelial tissue compared traditional stage scanning. By enabling rapid scanning, minimizing motion artifacts, reducing mechanical complexity, this technique has potential enhance vivo three-dimensional imaging endomicroscopy.
Porous shape memory polymers (SMPs) include foams, scaffolds, meshes, and other polymeric substrates that possess porous three-dimensional macrostructures. SMPs exhibit active structural volumetric transformations have driven investigations in fields ranging from biomedical engineering to aerospace the clothing industry. The present review article examines recent developments SMPs, with focus given chemical classification, methods of characterization, applications. We conclude current body...
There is an increasing interest in the application of fluorescence lifetime imaging (FLIM) for medical diagnosis. Central to clinical translation FLIM technology development compact and high-speed clinically compatible systems. We present a handheld probe design consisting small maneuverable box fitted with rigid endoscope, capable continuous at multiple emission bands simultaneously. The system was characterized using standard fluorescent dyes. performance then further demonstrated by...
We present a novel chromatic confocal microscope capable of volumetric reflectance imaging microstructure in non-transparent tissue. Our design takes advantage the aberration aspheric lenses that are otherwise well corrected. Strong aberration, generated by multiple aspheres, longitudinally disperses supercontinuum light onto sample. The backscattered detected with spectrometer is therefore wavelength encoded and each spectrum corresponds to line image. This approach obviates need for...
Optical imaging techniques using a variety of contrast mechanisms are under evaluation for early detection epithelial precancer; however, tradeoffs in field view (FOV) and resolution may limit their application. Therefore, we present multiscale multimodal optical system combining macroscopic biochemical fluorescence lifetime (FLIM) with subcellular morphologic reflectance confocal microscopy (RCM). The FLIM module images 16×16 mm2 tissue area 62.5 μm lateral 320 ps temporal to guide cellular...
Significance: There have been numerous academic and commercial efforts to develop high-resolution in vivo microscopes for a variety of clinical use cases, including early disease detection surgical guidance. While many high-profile studies, commercialized products, publications resulted from these efforts, mainstream adoption has relatively slow other than few applications (e.g., dermatology). Aim: Here, our goals are threefold: (1) introduce motivate the need microscopy (IVM) as an...
Fluorescence lifetime imaging (FLIM) offers a noninvasive approach for characterizing the biochemical composition of biological tissue. There has been an increasing interest in application multispectral FLIM medical diagnosis. Central to clinical translation technology is development compact and high-speed endoscopy systems. Unfortunately, predominant approaches suffer from limitations that impede systems are suitable vivo tissue imaging. We present wide-field time-gated flexible endoscope...
Blood, saliva, mucus, sweat, sputum, and other biological fluids are often hindered in their ability to be used point-of-care (POC) diagnostics because assays require some form of off-site sample pre-preparation effectively separate biomarkers from larger components such as cells. The rapid isolation, identification, quantification proteins small molecules circulating the blood plasma interfering therefore particularly important factors for optical diagnostic tests, particular, when using...
Abstract Human mesenchymal stem cells (hMSCs) are effective in treating disorders resulting from an inflammatory or heightened immune response. The hMSCs derived induced pluripotent (ihMSCs) share the characteristics of tissue but lack challenges associated with limited sources and donor variation. To meet expected future demand for ihMSCs, there is a need to develop scalable methods their production at clinical yields while retaining immunomodulatory efficacy. Herein, we describe platform...
We have performed a pilot clinical study, in which multispectral endogenous fluorescence (or autofluorescence) lifetime imaging (FLIM) was on clinically suspicious oral lesions of 73 patients undergoing tissue biopsy for dysplasia and cancer diagnosis. The results from this study indicated that mild-dysplasia early stage could be detected benign using computed aided diagnosis system developed based biochemical metabolic biomarkers derived the FLIM images. diagnostic performance novel tool...
Purpose: Mesenchymal stem cells (MSCs) have demonstrated clinically relevant therapeutic effects for treatment of trauma and chronic diseases. The proliferative potential, immunomodulatory characteristics, multipotentiality MSCs in monolayer culture is reflected by their morphological phenotype. Standard techniques to evaluate viability are subjective, destructive, or time-consuming. We present an image analysis approach objectively determine phenotype prediction efficacy. Approach:...
We present a single fiber reflectance confocal microscope with two dimensional MEMS gimbaled scanner. Achieved lateral and axial resolutions are 0.82 mum 13 mum, respectively. The field of view is 140 x 100 at 8 frames/second. Images videos cell phantoms tissue presented sub-cellular resolution.
We developed a technique for constructing light diffusing devices comprised of flexible shape memory polymer (SMP) cylindrical diffuser attached to the tip an optical fiber. The are fabricated by casting SMP rod over cleaved fiber and media blasting create surface. axial polar emission profiles circumferential (azimuthal) uniformity characterized various pressures, nozzle-to-sample distances, nozzle translation speeds. diffusers generally strongly forward-directed consistently withstand 8 W...
A variety of innovative point-of-care (POC) solutions using Raman systems have been explored. However, the vast effort is in assay development, while studies characteristics required for spectrometers to function POC applications are lacking. In this study, we tested and compared performance eight commercial ranging size from benchtop microscopes portable handheld paper fluidic cartridges, including their ability detect cardiac troponin I heart fatty acid binding protein, both which...
This paper presents the design and evaluation of a reflectance confocal laser endomicroscope using miniature objective lens within rigid probe in conjunction with an electrically tunable for axial scanning. The was characterized alone as well endoscope across 200 µm scan range lens. ability to human oral cavity is demonstrated by imaging mucosa vivo. results indicate that endomicroscopy has potential be used clinical setting guide diagnostic biological tissue.
Whole-animal fluorescence imaging with recombinant or fluorescently-tagged pathogens cells enables real-time analysis of disease progression and treatment response in live animals. Tissue absorption limits penetration excitation light, particularly the visible wavelength range, resulting reduced sensitivity to deep targets. Here, we demonstrate use an optical fiber bundle deliver light into mouse lung excite fluorescent bacteria, circumventing tissue whole-animal imaging. We present this...
A reflectance confocal endomicroscope with double-clad fiber coupler and electrically tunable focus lens is applied to imaging of the oral mucosa. The instrument designed be lightweight robust for clinical use. allows axial scanning through >250 μm in epithelium when probe tip placed contact tissue. Images are acquired at 6.6 frames per second a field view diameter up 850 μm. In vivo wide range normal sites cavity demonstrates accessibility handheld probe. lesions diagnosed as inflammation...
Automatic segmentation of nuclei in reflectance confocal microscopy images is critical for visualization and rapid quantification nuclear-to-cytoplasmic ratio, a useful indicator epithelial precancer. Reflectance can provide three-dimensional imaging tissue vivo with sub-cellular resolution. Changes nuclear density or ratio as function depth obtained from be used to determine the presence stage cancers. However, low background contrast, resolution at greater depths, significant variation...
We present a mechanical-scan-free method for volumetric imaging of biological tissue. The optical sectioning is provided by structured illumination, and the depth plane varied using an electrically tunable-focus lens. characterize evaluate ability this axial-scanning mechanism in illumination microscopy demonstrate its to perform subcellular resolution oral mucosa ex vivo. proposed can potentially convert any wide-field microscope 3D-imaging platform without need mechanical scanning optics...
In this paper, we demonstrate the ability of structured illumination microscopy to enhance fluorescence lifetime imaging resolve lifetimes in relatively thick samples that possess distinct but spectrally overlapping fluorescent layers.Structured (SI-FLIM) is shown be able accurately reconstruct values homogenous fluorophore (POPOP, NADH, and FAD) as well measure two layer models are layered with NADH/FAD over POPOP, where POPOP have spectral overlap.Finally, SI-FLIM was demonstrated a...
Raman spectroscopy using aluminum nitride (AlN) optical waveguides was demonstrated for organic compound analysis. The AlN waveguide device prepared by reactive sputtering deposition and complementary-metal-oxide semiconductor (CMOS) processes. A fundamental mode observed over a broad visible spectrum the evanescent wave used to excite signals of test analytes. performance sensor characterized measuring spectra benzene derivative mixtures consisting benzene, anisole, toluene. compositions...