Eyelid illumination systems and methods for imaging meibomian glands for meibomian gland analysis are disclosed. In one embodiment, a patient's eyelid is IR trans-illuminated with an infrared (IR) light. A trans-illumination image of the patient's eyelid is captured, showing meibomian glands in dark outlined areas, whereas non-gland material is shown in light areas. This provides a high contrast image of the meibomian glands that is X-ray-like. The lid trans-illumination image of the meibomian glands can be analyzed to determine to diagnose the meibomian glands in the patient's eyelid. The eyelid may be trans-illuminated by a lid-flipping device configured to grasp and flip the eyelid for imaging the interior surface of the eyelid. Also, an IR surface meibography image of the meibomian glands may also be captured and combined with the trans-illumination image of the meibomian glands to provide a higher contrast image of the meibomian glands.

A method and a system are disclosed for extracting important signal information. The method examines a group of signals obtained from testing of a patient's nervous system and finds a signal area of interest. Once a cluster of signals that all have the area of interest is found—the system concludes that the area of interest is located and validated. Signals that are not within the cluster are rejected and the signals within the cluster are signal-averaged to yield a signal-averaged waveform. The signal averaged waveform represents the results of the test.

An instrument includes: one or more scanning mirrors to receive an OCT sample beam and to scan the sample beam in two orthogonal directions; and an optical system to receive the sample beam and provide the sample beam to an eye. The optical system includes: a first lens having a first focal length, disposed along an optical path from the scanning mirror(s) to the eye at a distance from the cornea which is approximately equal to the first focal length, and a second lens disposed along the optical path between the first lens and the scanning mirror(s). The second lens receives the sample beam from the scanning mirror(s) and provides the sample beam to the first lens as a converging beam such that, as the sample beam is scanned, the sample beam passes through a pivot point located along an optical axis between the eye and the first lens.

The present invention provides reagents and methods for modulating cone photoreceptor activity, and devices for assessment of cone photoreceptor activity.

A contact lens system includes a shared antenna electrode, an accommodation actuator to provide variable optical power, and a controller coupled to the accommodation actuator and the shared antenna electrode. The controller including logic for arbitrating access to the shared antenna electrode between an impedance sensor and a communication circuit; selectively establishing an oscillator with the impedance sensor and the shared antenna electrode; correlating an oscillation condition of the oscillator to an accommodation setting; and adjusting the variable optical power of the accommodation actuator based upon the accommodation setting. An impedance across the shared antenna electrode varies based upon an amount an eyelid overlaps the contact lens system when the contact lens system is worn on an eye.

Intraocular physiological sensor implants include a physiological sensor, and a housing comprising a faceplate. The physiological sensor is integrated with the faceplate. The physiological sensor typically comprises an intraocular pressure sensor, such as a capacitive pressure sensor that may further include a flexible diaphragm electrode spaced apart from a counter electrode. The intraocular pressure sensor detects intraocular pressure, to identify patient conditions such as glaucoma.

Aspects of the present invention relate to a method of detecting clipping of retinal image content in an optical coherence tomography, OCT, image of a patient’s retina. The method comprises detecting a boundary of the retinal image content in the OCT image and calculating a distance between the boundary and an edge of the OCT image. The method further comprises determining if clipping of the retinal image content in the OCT image has occurred by comparing the calculated distance between the boundary and the edge of the OCT image with a clipping threshold distance. Clipping of the retinal image content is determined to have occurred when the calculated distance between the boundary and the edge of the OCT image is equal to, or less than, the clipping threshold distance.

Embodiments of the present disclosure describe a biomarker-responsive bifocal contact lens comprising a monovision contact lens having a first focal length and a Fresnel contact lens having a second focal length, wherein the Fresnel contact lens comprises a biomarker-responsive hydrogel, and wherein the Fresnel contact lens is disposed on an outer surface of the monovision contact lens, wherein an optical characteristic of the Fresnel contact lens changes in response to the biomarker concentration in the ocular fluid.

Microchannels in hydrogels play an essential role in enabling a smart contact lens. A wearable contact lens is disclosed herein that uses microchannels and connected chambers located in poly-2-hydroxyethyl methacrylate (poly(HEMA)) hydrogel that is used in a commercial contact lens with three-dimensional (3D) printed mold. The corresponding capillary flow behaviors in these microchannels were investigated. Different capillary flow regimes were observed in these microchannels, depending on the hydration level of the hydrogel material. In particular, it was found that a peristaltic pressure could reinstate flow in a dehydrated microchannel, indicating the motion of eye-blinking may help tear flow in a microchannel-containing contact lens. Colorimetric pH and electrochemical Na.sup.+ sensing capabilities were demonstrated in these microchannels. Micro-engineered contact lenses formed using poly(HEMA) hydrogel can be used for various biomedical applications such as eye-care and wearable biosensing.

A zwitterionic compound has a structure of following formula (1), formula (2), formula (3), or formula (4):

##STR00001## R.sub.1 is —O.sup.−, —(CH.sub.2).sub.aSO.sub.3.sup.−, or —(CH.sub.2).sub.bCO.sub.2.sup.−, a is 1 to 10, and b is 1 to 10. R.sub.2 and R.sub.3 are each independently an alkyl group or a phenyl group. x, z, and v are each independently 1 to 20. y and t are each independently 0 to 10.