Abstract: An endophotocoagulation probe has a probe tip adapted for insertion into the eye of a subject, and includes an optical fiber for carrying light, and a lens for focusing the light from the end of the fiber onto target tissue at a desired working distance. The lens forms a convergent beam with the waist of the beam providing a spot of maximum power density whose size is independent of the ocular medium. In a preferred embodiment a positioner provides selective variation of the spacing between the lens and the fiber to select a desired spot size. Preferably the lens is a selfocal or rod lens. A step-positioning handle selects one of a plurality of determined spacings, so as to achieve plural different spot sizes, each having a predetermined power density. Examples of probes having variable spot sizes in ranges from 50 to 500 microns are described with particular fibers and selfocal lens elements. A microprocessor may control lens position and light input power in accordance with the selected spot size.

Abstract: An eye movement tracker for stabilizing in two dimensions a diagnostic, treatment or other ophthalmic illumination on the fundus has a laser source which produces a narrow directed tracking beam, an optical steering assembly for controllably directing the beam to illuminate a region of the fundus, and an optical imaging assembly for imaging the illuminated region on a spatially-distributed photodetecting element. A tracking circuit scans the detecting element to detect motion of a spatially variant intensity feature and controls the optical steering assembly to redirect the optical path and maintain the feature in a fixed position. This repositions the diagnostic or other illumination, maintaining it in a fixed position on the fundus during eye movement. Scanning rates many times those of conventional systems are achieved, effectively stabilizing even very rapid eye movements. A viewing port provides an operator with a 30 degree field of the subject's eye fundus.

Abstract: An ophthalmic preparation and a method for preparing the ophthalmic preparation is described. The ophthalmic preparation has an enhanced ability to permit essentially normal maintenance of ocular surface mucus-containing goblet cells while present in the eye.

Abstract: An optical instrument which operates with an incident optical beam scanned at high rates and with correspondingly small sized scanning devices, has a double-scanning optical system. The output reflected beam that is detected overfills the first-stage scanning element, yet the instrument attains a relatively high-contrast image. The instrument provides for astigmatism correction, graphic generation in the scanned beam, and the use of infrared wavelength laser beams as well as visible wavelength laser beams. It also provides for generating system timing pulses from a rotating scanning element.

Abstract: An optical apparatus for providing a two-dimensional output representation of reflection characteristics of an eye fundus in which a laser beam is passed through an anamorphic optical element to produce an output beam focused on a first axis and dispersed on a second axis normal to the first axis forming a line. The line of the output beam is directed onto a scanning element which moves the beam along the first axis and a focusing element directing the output beam from the scanning element through the pupil of the eye onto the fundus, the size of the beam being such that it has a small cross sectional area at the pupillary plane of the eye compared to the diameter of the pupil. The light from the fundus is reflected back through an exit aperture which is large compared to the cross sectional dimension of the input beam at the pupillary plane. The device includes a detector which extends along the non-scanning coordinate of the scanned area.

Abstract: An optical instrument which operates with an incident optical beam scanned at high rates and with correspondingly small sized scanning devices, has a double-scanning optical system. The output reflected beam that is detected overfills the first-stage scanning element, yet the instrument attains a relatively high-contrast image.

Abstract: An optical instrument which operates with an incident optical beam scanned at high rates and with correspondingly small sized scanning devices, has a double-scanning optical system. The output reflected beam that is detected overfills the first-stage scanning element, yet the instrument attains a relatively high-contrast image. The instrument provides for astigmatism correction, graphic generation in the scanned beam, and the use of infrared wavelength laser beams as well as visible wavelength laser beams. It also provides for generating system timing pulses from a rotating scanning element.

Abstract: An in vitro testing method for biocompatibility, particularly toxicological effect, of substances is based on the change in the time for closure of a disruption in a confluent cell culture caused by treatment with the substance. The method can be used to replace a substantial number of toxicity tests, including the Draize test for ocular irritancy.

Abstract: A method and preparation for the stimulation of tear secretion. The method involves topically applying a phosphodiesterase inhibitor and/or cyclic nucleotide analogue to the ocular surface. Inhibition of phosphodiesterase and cyclic nucleotide analogues increase cyclic nucleotide levels in lacrimal gland tissue, thereby stimulting tear secretion. The preparation contains a phosphodiesterase inhibitor or a cyclic nucleotide analogue and a vehicle for the phosphodiesterase inhibitor or cyclic nucleotide analogue, and may contain an ophthalmic preservative.

Abstract: A method for evaluating the in vivo ability of a contact lens to become or remain wet includes the steps of supporting the subject's head to determine a fixed orientation of the lens, illuminating the lens with coherent light, imaging the pre-lens tear film in a manner to form an interference pattern, recording in a time sequence manner the image formed thereby, and determining the tear film thickness by correlating the interference bands of the recorded image. The classical contact angle is derived, and other measures, such as the time interval from blink until the onset of the tear film breakup, or the time until the film evaporates, and the initial or average film thickness are derived. In addition, the nature and evolution of localized dry spots may be directly observed, clarifying the causes of tear film breakdown on worn contact lenses.

Abstract: A method and preparation for the stimulation of tear secretion. The method involves topically applying to the ocular surface gastrointestinal hormones and/or biologically active peptides and their precursors, derivatives, and fragments which activate vasoactive intestinal peptide receptors of lacrimal gland tissue. The preparation contains a peptide of hormone that activates the vasoactive intestinal peptide receptor such as glucagon or vasoactive intestinal peptide, a vehicle and may also contain an ophthalmic preservative.

Abstract: An apparatus for performing measurements on the eye of a subject includes a headrest for supporting the head of the subject in a fixed position, and a frame holding a light source directing illumination at the eye. The frame is adapted for pivotal motion about a central axis of the eye. Imaging means provides an image of the first and fourth Purkinje images of the light, and means are provided for measuring the amount of rotation of the frame. The frame may be initially aligned so that a fixation target lies in the plane defined by the central axis and the light source, and then rotated until the first and fourth Purkinje images determine a straight line parallel to the central axis, whereby the plane is aligned with the optical axis of the eye. The net rotation of the frame then gives a direct reading of the angular difference between the line to the target and the optical axis of the eye. Preferably the apparatus includes an infrared light source.

Abstract: A stereoscopic ophthalmoscope for use with a condensing lens to observe the fundus of a patient's eye, the ophthalmoscope having a left eyepiece and a right eyepiece, a light source for directing light into the patient's eye so that an image of the patient's eye is focused by the condensing lens in a focal plane perpendicular to an optical axis, the ophthalmoscope having the improvements consisting of an image-splitting device for splitting the image into a left image and a right image travelling along a left optical path and a right optical path, respectively, left and right image-rotating devices arranged in optical alignment with the image-splitting device for inverting and reversing each of the left and right images from the image-splitting device, and left and right magnifying devices, each including an objective lens and an ocular lens and each arranged in optical alignment with the respective image-rotating devices to magnify the image therefrom and to transmit that image to the respective eyepiece.

Abstract: A surgical ophthalmoscope for observing the fundus of a patient's eye, the ophthalmoscope having a left eyepiece and a right eyepiece, a light source for directing light into the patient's eye, a condensing lens for focusing an image of the patient's eye in a focal plane perpendicular to an optical axis, a telescopic tube, an image-interchanging device for splitting the image into a left image and a right image and then interchanging the images such that image rays entering the right side of the condensing lens are directed to a right optical path, while image rays from the left side are directed to a left optical path, and left and right magnifying devices, each including an objective lens and an ocular lens situated between the image-interchanging device and the eyepieces in optical alignment to magnify the interchanged images and to transmit the magnified images to the respective eyepieces.

Abstract: The non-intrusive measurement of preocular tear film evaporation employs a goggle fitted on a subject and connected with apparatus for introducing air of known conditions to a goggle chamber over one eye, apparatus for controlling air movement within the goggle chamber, and apparatus for humidity measurement of the chamber air.A measure of palpebral aperture readily provides the area of the exposed eye surface, for calculating the rate of tear evaporation.

Abstract: A hydrogel implant article of significant softness, pliability and elasticity when dry as well as when wet consists of a random cross-linked copolymer of 2-hydroxyethyl acrylate and an alkyl acrylate. The acrylate hydrogel article is useful, in one instance, as the material to produce a scleral buckle in retinal detachment surgery.

Abstract: A wide-angle indirect ophthalmoscope that enables an operator to view the retina from the posterior pole to the equator as a single image. The ophthalmoscope has an observable field that can include the entire retina. The ophthalmoscope includes optical fibers built into a contact lens in a circular pattern. The fibers are connected to a light source to illuminate the retina, and the contact lens is utilized for observation. The fibers are maintained in a pre-determined fixed orientation in the lens to produce uniform illumination over the entire retina.

Abstract: A scanning ophthalmoscope for repeatedly scanning a selected portion of an eye fundus has a laser source which produces a directed narrow-beam output and means for scanning the fundus with at least one selected scanning sequence. The scanning beam passes through a pivot point located in a preselected plane, preferably within the eye, for providing a wide field of view. An optical system directs light reflected from the fundus to a detector, which produces an electrical output signal proportional to the detected light. An output element provides a visual representation of the magnitude of the output signal in a spatial distribution corresponding to the scanning sequence.

Abstract: Apparatus for viewing an eye fundus through a contact lens has an illuminating element that illuminates the fundus through the sclera. The illuminating element includes at least one fiber optic bundle with an exit facet for placement contiguous with the sclera, generally through whatever thickness of occular conjunctiva is present. The apparatus also has an optical mask system which masks the image of the fundus portion most intensely illuminated by the fiber optic exit facet to control over-illumination of that fundus portion.

Abstract: A beam of laser light is impinged on a vessel or vessels in which blood is flowing, such as vessels in the retina of the eye. The reflected light is detected with a photodetector to product a signal representative of the Doppler shift frequencies of the light scattered from the moving blood cells. If the light is impinged on a capillary bed the photodetector produces a homodyne type signal, from light reflected from blood in the various capillaries; if the light is impinged on a single vessel the photodetector produces a heterodyne type signal from the light reflected from the vessel wall and the light reflected from the blood cells flowing in the vessel. The signal from the photodetector is amplified and used to drive an audio output to produce a sound representative of the velocity of the blood.