# US 12,109,147 B2 · Method and system for automation of patient eye level > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,109,147 B2 - Document ID: US12109147B2 - Status: Granted - Kind: B2 - Application number: 17/209,305 - Filed: 2021-03-23 - Published: 2021-09-30 - Granted: 2024-10-08 - Earliest claimed: 2020-03-30 - Assignees: Alcon Inc. - Applicants: Alcon Inc. - Inventors: Sean Christopher Madden - Web page: https://patentgrep.com/patent/US12109147B2 ## CPC - A61B 3/13: Ophthalmic microscopes - A61F 9/007: Methods or devices for eye surgery - A61B 3/14: Arrangements specially adapted for eye photography - A61B 90/361: {Image-producing devices, e.g. surgical cameras} - G02B 21/0012: {Surgical microscopes (counterbalanced structures for surgical microscopes G02B7/001)} - A61B 3/165: {Non-contacting tonometers} - A61B 34/30: Surgical robots - A61B 90/25: Supports therefor - A61B 2090/367: {creating a 3D dataset from 2D images using position information} - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - A61F: FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS (dental prosthetics A61C) - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An ophthalmic surgical system includes a robotic arm disposed above a patient's eye. A positioning camera is disposed on the robotic arm and positioned to visualize the patient's eye. A processor is electrically coupled to the positioning camera. The processor is configured to receive an indication of a position of the robotic arm relative to a fixed datum, determine a focal length between the positioning camera and the patient's eye, compare the focal length to the position of the robotic arm, and determine a patient eye level relative to the fixed datum. ## Claims ### Claim 1 An ophthalmic surgical system, comprising: a robotic arm disposed above a patient's eye; a positioning camera disposed on the robotic arm and positioned to visualize the patient's eye; a processor electrically coupled to the positioning camera, the processor being configured to: receive an indication of a position of the robotic arm relative to a fixed datum; determine a focal length between the positioning camera and the patient's eye; determine a patient eye level relative to the fixed datum by comparing the focal length to the position of the robotic arm; and determine an intraocular pressure set point based on the patient eye level. ### Claim 2 (depends on 1) The ophthalmic surgical system of claim 1, wherein the fixed datum is a floor of a surgical suite. ### Claim 3 (depends on 2) The ophthalmic surgical system of claim 2, wherein the position of the robotic arm relative to the fixed datum is a height of the robotic arm above the floor of the surgical suite. ### Claim 4 (depends on 2) The ophthalmic surgical system of claim 2, wherein the patient eye level relative to the fixed datum is a height of the patient's eye above the floor. ### Claim 5 (depends on 1) The ophthalmic surgical system of claim 1, wherein the positioning camera is a three-dimensional stereoscopic camera. ### Claim 6 (depends on 1) The ophthalmic surgical system of claim 1, comprising an encoder coupled to the robotic arm, the encoder being configured to determine a position of the robotic arm relative to the fixed datum. ### Claim 7 (depends on 6) The ophthalmic surgical system of claim 6, wherein the encoder is electrically coupled to the processor. ### Claim 8 (depends on 7) The ophthalmic surgical system of claim 7, wherein the encoder is at least one of a linear encoder and an angular encoder. ### Claim 9 A surgical microscope, comprising: a positioning camera positioned to visualize a patient's eye; an encoder coupled to the positioning camera, the encoder being configured to determine a position of the positioning camera relative to a fixed datum; a processor electrically coupled to the encoder and the positioning camera, the processor being configured to: receive an indication of a position of the positioning camera relative to the fixed datum; determine a focal length between the positioning camera and the patient's eye; determine a patient eye level relative to the fixed datum by comparing the focal length to the position of the positioning camera; and determine an intraocular pressure set point based on the patient eye level. ### Claim 10 (depends on 9) The surgical microscope of claim 9, wherein the fixed datum is a floor of a surgical suite. ### Claim 11 (depends on 10) The surgical microscope of claim 10, wherein the position of the positioning camera relative to the fixed datum is a height of the positioning camera above the floor of the surgical suite. ### Claim 12 (depends on 11) The surgical microscope of claim 11, wherein the patient eye level relative to the fixed datum is a height of the patient's eye above the floor. ### Claim 13 (depends on 9) The surgical microscope of claim 9, wherein the positioning camera is a three-dimensional, stereoscopic camera. ### Claim 14 (depends on 9) The surgical microscope of claim 9, wherein the encoder is at least one of a linear encoder and an angular encoder. ### Claim 15 A method of determining patient eye level, the method comprising: focusing a positioning camera on a patient's eye; determining a position of the positioning camera relative to a fixed datum; determining a focal length between the positioning camera and the patient's eye; determining the patient eye level by comparing the focal length to the position of the positioning camera relative to the fixed datum; and determining an intraocular pressure set point based on the patient eye level. ### Claim 16 (depends on 15) The method of claim 15, wherein the determining the position of the positioning camera relative to the fixed datum comprises determining a height of the positioning camera above a floor of a surgical suite. ### Claim 17 (depends on 16) The method of claim 16, wherein the patient eye level is a height of the patient's eye above the floor of the surgical suite. ### Claim 18 (depends on 15) The method of claim 15, wherein the determining the focal length is performed continuously. ### Claim 19 (depends on 18) The method of claim 18, wherein continuous determination of the focal length facilitates adjustment of the intraocular pressure set point during an ophthalmic surgical intervention.