A5020019009- Photoacoustic and Ultrasonic Imaging
- Nanoplatforms for cancer theranostics
- Optical Imaging and Spectroscopy Techniques
- Thermography and Photoacoustic Techniques
- Photorefractive and Nonlinear Optics
- Photonic and Optical Devices
- Advanced Optical Imaging Technologies
- Advancements in Transdermal Drug Delivery
- Allergic Rhinitis and Sensitization
- Spectroscopy Techniques in Biomedical and Chemical Research
- Optical Coherence Tomography Applications
- Optical measurement and interference techniques
- Advanced Fiber Laser Technologies
- dental development and anomalies
- Surface Roughness and Optical Measurements
- Dermatology and Skin Diseases
- Bone and Dental Protein Studies
- Bee Products Chemical Analysis
- Thermoregulation and physiological responses
- Extracellular vesicles in disease
- Dental Trauma and Treatments
- Laser Material Processing Techniques
- Transition Metal Oxide Nanomaterials
- Thermal Regulation in Medicine
- Protein Interaction Studies and Fluorescence Analysis
University of Liverpool
2024
Singapore Bioimaging Consortium
2018-2023
Agency for Science, Technology and Research
2018-2023
Institute of Materials Research and Engineering
2023
Nanyang Technological University
2016-2018
Technological University Dublin
2011
Photoacoustic microscopy (PAM) is a scalable bioimaging modality; one can choose low acoustic resolution with deep penetration depth or high optical shallow imaging depth. High spatial and rather difficult to achieve using single system. Here we report switchable photoacoustic (AR-OR-PAM) system in capable of both on the same sample. Lateral 4.2 µm (with ~1.4 mm depth) lateral 45 μm ~7.6 was successfully demonstrated In vivo blood vasculature also performed for its biological application.
Microneedle technology allows micron-sized conduits to be formed within the outermost skin layers for both localized and systemic delivery of therapeutics including nanoparticles.Histological methods are often employed characterization, unfortunately do not allow in vivo visualization process.This study presents utilization optical resolution-photoacoustic microscopy characterize transdermal nanoparticles using microneedles.Specifically, we observe gold microneedles mice ear penetration,...
Equine odontoclastic tooth resorption and hypercementosis (EOTRH) is a painful disorder primarily affecting the incisor teeth of horses over 15 years age. Clinical signs disease include prehension problems, halitosis in severe cases weight loss. The predominately affects reserve crown presents as loss dental tissue excessive build-up cementum. To determine radiographic scores with EOTRH age-matched controls to increase understanding using microCT compare from controls. In vivo ex studies....
Photoacoustic microscopy (PAM) is a fast-growing biomedical imaging technique that provides high-resolution <italic>in vivo</italic> beyond the optical diffusion limit. Depending on scalable lateral resolution and achievable penetration depth, PAM can be classified into (OR-PAM) acoustic (AR-PAM). The use of microelectromechanical systems (MEMS) scanner has improved OR-PAM speed significantly highly beneficial in development miniaturized handheld devices. shallow depth limits such devices...
Pressure ulcer formation is a common problem among patients confined to bed or restricted wheelchairs. The forms when the affected skin and underlying tissues go through repeated cycles of ischemia reperfusion, leading inflammation. This theory evident by intravital imaging studies performed in immune cell–specific, fluorescent reporter mouse with induced ischemia‐reperfusion (I‐R) injuries. However, traditional confocal multiphoton microscopy cannot accurately monitor progression vascular...
Photoacoustic microscopy (PAM) is a multiscale imaging technique. In optical-resolution photoacoustic (OR-PAM), single mode (SM) fiber normally used as the source of optical excitation to be focused into diffraction-limited spot. Recent advances in OR-PAM have improved its speed using microelectromechanical systems (MEMS). Here we report for first time use multimode (MM) high resolution vivo imaging. A high-speed MEMS scanner based system combined with mechanical movement provide wide area...
The use of an optical resolution photoacoustic microscopy (OR‐PAM) system to evaluate the vascular disruptive effect combretastatin A4 Phosphate (CA4P) on a murine orthotopic glioma with intact skull is described here. Second generation optical‐resolution scanner 532 nm pulsed diode‐pumped solid‐state laser that specifically matches absorption maximum hemoglobin in tissues was used image inoculated mouse brain. Two‐dimensional maps brain vasculature lateral 5 μm and depth 700 at field view ×...
Clinical Practice Points•Multispectral optoacoustic tomography (MSOT) is an innovative state-of-the-art imaging modality that has gained popularity for in vivo breast recent years.•Combining high-resolution images with endogenous differentiation of biochemical contents, MSOT could be accurate ex assessment tumor margins during breast-conserving surgery to reduce margin positivity rates.•Accurate intraoperative lead more precise surgery, allowing a smaller volume tissue removed without...
We study the shrinkage in acrylamide based photopolymer by measuring Bragg detuning of transmission diffraction gratings recorded at different slant angles and intensities for a range spatial frequencies. Transmission frequencies 500, 1000, 1500 2000 lines/mm were an film having 60 ± 5 μm thickness. The grating thickness final obtained from angular selectivity curve hence caused holographic recording was calculated. material evaluated three 1, 10 mW/cm2 over angles, while total exposure...
Atopic dermatitis (AD) is a chronic and pruritic skin inflammatory disease causing significant burden to health care management patient's quality of life. Seemingly healthy or non-lesional sites on AD patients still presents barrier defects immune response, which can develop at later stage. To investigate further the balance between epidermal impairment intrinsic dysregulation in AD, we exploited multispectral Raster-Scanning Optoacoustic Mesoscopy (ms-RSOM) image lesional areas different...
An acrylamide based photopolymer doped with pure silica MFI-type zeolite (silicalite-1) nanoparticles has been characterized for holographic recording purposes. The concentrations of the silicalite-1 in layers were 1, 2.5, 5 and 7.5 wt. %. inclusion nanoparticle resulted an increase diffraction efficiency by up to 40%, decrease shrinkage from 1.32% 0.57%. best results obtained % nanoparticles.
Due to the embedded nature of lamina cribrosa (LC) microcapillary network, conventional imaging techniques have failed obtain high-resolution images needed assess perfusion state LC. In this study, both optical resolution (OR) and acoustic (AR) photoacoustic microscopy (PAM) were used static dynamic information about LC in ex vivo porcine eyes. The OR-PAM system could resolve a perfused network with lateral 4.2 μm also provided good depth (33 axial resolution) visualize through-thickness...
Shrinkage of photopolymer materials is an important factor for their use in holographic data storage and fabrication optical elements. Dimensional change the element leads to a requirement compensation reading angle and/or wavelength. Normally, shrinkage studied at end polymerization process no information about dynamics obtained. The aim this study was interferometry measure that occurs during recording transmission diffraction gratings acrylamide layers. layers can be measured over whole...
The ability to monitor oxygen delivery in microvasculature plays a vital role measuring the viability of skin tissue and probability recovery. Using currently available clinical imaging tools, it is difficult observe non-invasive hemodynamic regulation peripheral vessels. Here we propose use novel multispectral raster-scanning optoacoustic mesoscopy (RSOM) system for noninvasive monitoring changes microvasculature's oxy- (HbO2) deoxy-hemoglobin (Hb), total hemoglobin (HbT) saturation (rsO2)....
Photoacoustic microscopy (PAM) can be classified as optical resolution (OR)-PAM and acoustic (AR)-PAM depending on the type of achieved. Using microelectromechanical systems (MEMS) scanner, high-speed OR-PAM system was developed earlier. Depth imaging limits use technology for many preclinical clinical applications. Here, we demonstrate a MEMS scanner AR-PAM imaging. Lateral 84 μm an axial 27 with ~2.7 mm depth achieved using 50 MHz transducer-based system. Use higher frequency transducer at...
In this pilot study, we tested an ultrasound-guided optoacoustic tomography (US-OT) two-dimensional (2D) array scanner to understand the patterns of excised breastconserving surgery (BCS) specimens. We imaged 14 BCS specimens containing malignant tumors at eight wavelengths spanning 700-1100 nm. Spectral unmixing across multiple allowed for visualizing major intrinsic chromophores in breast tissue including hemoglobin and lipid up a depth 7 mm. identified less/no signals within tumor intense...
Atopic dermatitis (AD) is a common chronic inflammatory skin dermatosis condition due to barrier dysfunction that causes itchy, red, swollen, and cracked skin. Currently, AD severity clinical scores are subjected intra- inter-observer differences. There need for an objective scoring method sensitive The aim of this study was evaluate the relevant chemical biomarkers in patients. We used confocal Raman micro-spectroscopy advanced machine learning methods as means classify eczema patients...
Photoacoustic tomography (PAT) is increasingly being used for high-resolution biological imaging at depth. Signal-to-noise ratios and resolution are the main factors that determine image quality. Various reconstruction algorithms have been proposed applied to reduce noise enhance resolution, but efficacy of signal preprocessing methods which also affect quality, seldom discussed. We, therefore, compared common techniques, namely bandpass filters, wavelet denoising, empirical mode...
Photoinduced shrinkage occurring in photopolymer layers during holographic recording was determined by phase shifting electronic speckle pattern interferometry. Phase maps were calculated from the changes intensity at each pixel due to differences introduced between object and reference beams. Shrinkage then obtained as proceeded. The technique allows for whole field measurement of dimensional photopolymers recording.