A5074791317- Optical Coherence Tomography Applications
- Retinal Imaging and Analysis
- Advanced Optical Sensing Technologies
- Optical Imaging and Spectroscopy Techniques
- Retinal Development and Disorders
- Adaptive optics and wavefront sensing
- Ophthalmology and Visual Impairment Studies
- Intraocular Surgery and Lenses
- Photoacoustic and Ultrasonic Imaging
- Advanced Fluorescence Microscopy Techniques
- Retinal Diseases and Treatments
- Optical measurement and interference techniques
- Retinopathy of Prematurity Studies
- Corneal surgery and disorders
- Glaucoma and retinal disorders
- Ocular and Laser Science Research
- Retinal and Macular Surgery
- Ophthalmology and Visual Health Research
- Optical Systems and Laser Technology
- Advanced biosensing and bioanalysis techniques
- Cell Image Analysis Techniques
- Gold and Silver Nanoparticles Synthesis and Applications
- Nanoparticle-Based Drug Delivery
Duke University
2015-2023
Optical Sciences (United States)
2020-2021
United States Naval Research Laboratory
2020
Harvey Mudd College
2014
The Shack-Hartmann wavefront sensor (SH-WFS) is known to produce incorrect measurements of the gradient in presence non-uniform illumination. Moreover, most common least-squares phase reconstructors cannot accurately reconstruct branch points. We therefore developed intensity/slopes network (ISNet), a deep convolutional-neural-network-based reconstructor that uses both information and intensity SH-WFS's subapertures provide better reconstruction. trained on simulated data with multiple...
Optical coherence tomography (OCT) has revolutionized diagnosis and prognosis of ophthalmic diseases by visualization measurement retinal layers. To speed up the quantitative analysis disease biomarkers, an increasing number automatic segmentation algorithms have been proposed to estimate boundary locations While performance these significantly improved in recent years, a critical question ask is how far we are from theoretical limit OCT performance. In this paper, present Cramèr-Rao lower...
Adaptive optics scanning laser ophthalmoscopy (AOSLO) has enabled in vivo visualization and enhanced understanding of retinal structure function. Current generation AOSLOs have a large footprint are mainly limited to imaging cooperative adult subjects. To extend the application AOSLO new patient populations, we designed first portable handheld (HAOSLO) system. By incorporating novel computational wavefront sensorless AO algorithm custom optics, miniaturized our HAOSLO weigh less than 200...
Non-confocal adaptive optics scanning laser ophthalmoscopy (AOSLO) has enhanced the study of human retinal photoreceptors by providing complementary information to standard confocal AOSLO images. Previously we developed first handheld (HAOSLO) capable in vivo cone photoreceptor imaging supine and non-cooperative patients. Here, introduce multimodal (M-)HAOSLO for non-confocal split-detection (SD) allow more comprehensive patient data collection. Aside from its unprecedented miniature size...
Handheld scanning laser ophthalmoscopy (SLO) and optical coherence tomography (OCT) systems facilitate imaging of young children subjects that have difficulty fixating. More compact lightweight probes allow for better portability increased comfort the operator handheld probe. We describe a very compact, novel SLO OCT probe design. A single 2D microelectromechanical (MEMS) scanner custom design using converging beam prior to permitted significant reduction in system size. Our utilized...
Conventional scanning laser ophthalmoscopy (SLO) utilizes a finite collection pinhole at retinal conjugate plane to strongly reject out-of-focus light while primarily transmitting the in-focus, backscattered signal. However, improve lateral resolution, sub-Airy disk is necessary, which drastically reduces signal-to-noise ratio (SNR) of system and thus not commonly employed. Recently, an all-optical, super-resolution microscopy technique known as optical photon reassignment (OPRA) (also...
Adaptive optics scanning laser ophthalmoscopy (AOSLO) has advanced the study of retinal structure and function by enabling in vivo imaging individual photoreceptors. Most implementations AOSLOs are large, complex tabletop systems, thereby preventing high quality photoreceptor patients who unable to sit upright and/or fixate for an session. We have previously addressed this limitation clinical translation AOSLO developing first confocal handheld (HAOSLO) capable cone visualization adults...
Excessive nonspecific binding often occurs when labeling cells with immuno-labeled gold nanoparticles (IgG-AuNPs). We have investigated the physical properties of IgG-AuNPs assembled three different protocols in an attempt to understand and eliminate this non-specific binding. One these involves conjugating secondary antibody AP124F via van der Waals (vdW) and/or electrostatic forces AuNPs, other two employ a PEG-linker, OPSS-PEG-NHS (OPN). In all we follow PEG-SH provide protection against...
In vivo photoreceptor imaging has enhanced the way vision scientists and ophthalmologists understand retinal structure, function, etiology of numerous pathologies. However, complexity large footprint current systems capable resolving photoreceptors limited to patients who are able sit in an upright position fixate for several minutes. Unfortunately, this excludes important fraction including bedridden patients, small children, infants. Here, we show that our dual-modality, high-resolution...
The human retina is composed of several layers, visible by in vivo optical coherence tomography (OCT) imaging. To enhance diagnostics retinal diseases, algorithms have been developed to automatically segment one or more the boundaries these layers. OCT images are corrupted noise, which frequently result detector noise and speckle, a type coherent resulting from presence scatterers each voxel. However, it unknown what empirical distribution layer is, how magnitude affects lower bounds...
Adaptive optics optical coherence tomography (AO-OCT) has allowed for the reliable 3-D imaging of individual retinal cells. The current AO-OCT systems are limited to tabletop implementation due their size and complexity. This work describes design first dual modality handheld (HAOOCT) scanning laser ophthalmoscope (SLO) probe extend previously excluded patients. Simultaneous SLO allows tracking features HAOOCT localization. Pilot experiments on stabilized recumbent adults using HAOOCT,...
Shack-Hartmann wavefront sensors are limited in turbulence by non-uniform illumination and branch points. We describe the Intensity/Slopes Network (ISNet), which reconstructs wavefronts from intensity slope information, demonstrate that it improves performance turbulence.
The incorporation of adaptive optics (AO) technology into ophthalmic imaging systems has enhanced the understanding retinal structure and function progression various diseases in adults by allowing for dynamic correction ocular and/or system aberrations. However, vivo visualization important human microanatomy, including cone photoreceptors, been largely limited to fully cooperative subjects who are able fixate sit upright extended sessions large tabletop AO systems. Previously, we developed...
A deep learning network for wavefront reconstruction based on intensity and slopes information (ISNet) is further improved by using realistic noise to generate a con- volutional neural net model accurate centroiding calculation.