Alcon, Inc.

Novartis Ag

Muhammad Al-Qaisi

Hugang Ren

Guy Holland

Brent G Duchon

Richard J Michaels

Steve Xiangling Chen

Sahar Hosseinzadeh Kassani

Craig Bender

Parisa Rabbani

Joseph Thomas Traynor

Bing Wang

Tomas Sedlacek

Antonije M Radojevic

Todd Schernig

An OCT imaging system may include an OCT light source operable to emit an OCT light beam, and a beam splitter operable to split the OCT light beam into a sample beam, transferred to a sample arm waveguide, and a reference beam, transferred to a reference arm waveguide. The sample arm waveguide and the reference arm waveguide may be coupled together within a cladding, wherein the cladding improves a calibration of a generated OCT image by fixing axial movement of the sample arm and reference arm waveguides relative to one another. By routing long reference and sample arm waveguide fibers together in the OCT system using a sheath/cladding, OCT image offset due to asymmetrical fiber stretching can be minimized or eliminated.

Common path waveguides for stable optical coherence tomography imaging

Systems and methods are disclosed for performing ophthalmic optical coherence tomography with multiple resolutions. In some embodiments, a system comprises a light source, an output lens, and a set of optical components between the light source and the output lens, the set of optical components comprising an afocal zoom telescope. The set of optical components is adapted to provide imaging both at a first field of view with a first resolution and at a second field of view with a second resolution, wherein the first field of view is wider than the second field of view and the second resolution is higher than the first resolution. A method of performing ophthalmic optical coherence tomography with multiple resolutions may be performed using one or more of the systems described herein.

Ophthalmic optical coherence tomography with multiple resolutions

Systems and methods are presented for providing a machine learning model for segmenting an optical coherence tomography (OCT) image. A first OCT image is obtained, and then labeled with identified boundaries associated with different tissues in the first OCT image using a graph search algorithm. Portions of the labeled first OCT image are extracted to generate a first plurality of image tiles. A second plurality of image tiles is generated by manipulating at least one image tile from the first plurality of image tiles, such as by rotating and/or flipping the at least one image tile. The machine learning model is trained using the first plurality of image tiles and the second plurality of image tiles. The trained machine learning model is used to perform segmentation in a second OCT image.

Deep learning for optical coherence tomography segmentation

An Optical Coherence Tomography receiver may include prisms, polarizing beam splitters, reflectors, lenses, and a photodetector array arranged in a compact package. Sample and reference beams are combined into an interference beam and split in two. The two resulting interference beams are then split into two polarization sates each. The optical path lengths for both pairs of interference beams with the same polarization state are equal or nearly equal.

Optical coherence tomography receiver

The present disclosure provides a system and method for cutting a flap in laser ophthalmic surgery using polarization sensitive optical coherence tomography (PS-OCT). The system includes a PS-OCT system, a femtosecond laser, control device, and processor. The PS-OCT system includes a PS-OCT source, a polarization component, a reference reflector, a beam splitter, a wave plate, and a detector. The processor receives data relating to an interference pattern of a reflected PS-OCT beam, received at the detector, determines a relative fiber orientation of the sample, determines whether a photodisruption pattern generated by the femtosecond laser to cut the flap should be adjusted horizontally or vertically, based on the relative fiber orientation, and may generate a control signal to adjust the photodisruption pattern generated by the femtosecond laser. The disclosure further provides a method for cutting a flap on an eye using PS-OCT.

System and method for cutting a flap using polarization sensitive optical coherence tomography

Techniques for measuring optical aberrations of the eye are disclosed. An example method comprises positioning the eye in a measurement location adjacent to a measurement arm of an optical coherence tomography (OCT) interferometer apparatus, so that source light from the measurement arm passes into the anterior segment of the eye and detecting an interference pattern, the interference pattern resulting from a combination of light reflected from the eye and light reflected from a reference arm of the OCT interferometer apparatus. Based on the interference pattern, an optical delay between a reference surface in the anterior segment of the eye and a measured surface in the eye is calculated, the reference surface being the anterior surface of the cornea or the lens, wherein said calculating comprises measuring an optical phase shift between the reference surface and the measured surface, based on the detected interference pattern.

Phase-sensitive optical coherence tomography to measure optical aberrations in anterior segment

A-lines are obtained from an OCT scan of the eye, some of which pass through the iris and the lens and some of which pass through the lens but not the iris. An interface is detected from the A-lines; at least some of this interface is assumed to correspond to either the anterior or posterior of the iris. For each A-line, a first metric is derived from pixels near the detected first interface, such that the first metric reflects an OCT signal intensity associated with the interface, and a second metric is derived from pixels further from the interface, such that the second metric reflects OCT signal attenuation below the detected interface. An attenuation parameter is calculated for each A-line, based on the first and second metrics, and the iris's edge is detected by determining whether each A-line passes through the iris, based on the attenuation parameter.

Iris edge detection in Optical Coherence Tomography

Techniques and apparatus for producing sampled Optical Coherence Tomography (OCT) interference signals without aliasing, based on a swept-source OCT interference signal. An example apparatus comprises a k-clock circuit configured to selectively output a k-clock signal at any of a plurality of k-clock frequencies ranging from a minimum k-clock frequency to a maximum k-clock frequency, and an anti-aliasing filter configured to filter a swept-source OCT interference signal, to produce a filtered OCT interference signal, where the anti-aliasing filter has a cut-off frequency greater than one-half the minimum k-clock frequency but less than the minimum k-clock frequency. The apparatus further comprises an analog-to-digital (A/D) converter circuit configured to sample the filtered OCT interference signal at twice the k-clock frequency, to produce a sampled OCT interference signal. In some embodiments, the A/D converter circuit samples the filtered OCT interference signal at both rising and falling edges of the k-clock signal.

Dual-edge sampling with k-clock to avoid aliasing in optical coherence tomography

Techniques and apparatus for selectively producing half-depth and full-depth OCT images, based on a swept-source OCT interference signal. An example method comprises selecting from a first sampling rate and a second sampling rate, the second sampling rate being twice the first sampling rate, and sampling the swept-source Optical Coherence Tomography (OCT) interference signal at the selected sampling rate, using a k-clock signal having a frequency range corresponding to the first sampling rate, to produce a sampled OCT interference signal. The method further comprises processing the sampled OCT interference signal to obtain an OCT image, such that the resulting OCT image is a half-depth image in the event the first sampling rate is selected and a full-depth image in the event the second sampling rate is selected.

Growing community of inventors

Ladera Ranch, CA, United States of America

Muhammad Al-Qaisi