JP-7856354-B1 - Phakic intraocular lens selection device and phakic intraocular lens selection program

JP7856354B1JP 7856354 B1JP7856354 B1JP 7856354B1JP-7856354-B1

Abstract

[Problem] To provide a device 1 that can reduce the risk of angle-to-angle narrowing after ICL (intraocular lens) implantation surgery. [Solution] The device 1 includes a calculation unit 5. The calculation unit 5 (acquisition unit) acquires at least the preoperative AOD (preoperative angle opening) from the patient undergoing ICL insertion surgery. The calculation unit 5 (calculation unit) also calculates the threshold value of vault, which is a pre-set index of narrow angle, using the acquired preoperative AOD, based on a threshold calculation formula that uses preoperative AOD and vault (distance) as variables. Furthermore, the calculation unit 5 (selection unit) selects the ICL lens size by referring to the calculated vault threshold value. [Selection Diagram] Figure 1

Inventors

市川一夫
市川慶
西田知也

Assignees

株式会社ＫＩメディック

Dates

Publication Date: 20260511
Application Date: 20251204

Claims (8)

An acquisition unit that acquires at least the preoperative angle of ocular shape parameters from patients who have undergone intraocular lens implantation, A calculation unit calculates a threshold for the distance that serves as an indicator of a narrow angle, based on a pre-set threshold calculation formula, using the preoperative angle opening and the distance from the anterior surface of the crystalline lens to the posterior surface of the crystalline lens in patients who have undergone phakic intraocular lens implantation, using the preoperative angle opening acquired by the acquisition unit as variables. The system includes a selection unit that selects the lens size of the phakic intraocular lens by referring to the distance threshold calculated by the calculation unit , The selection unit is a phakic intraocular lens selection device that selects a lens size for a phakic intraocular lens that corresponds to a predicted distance value smaller than the distance threshold calculated by the calculation unit, by referring to a lens size selection table for phakic intraocular lenses that is set in advance in accordance with the predicted distance value calculated based on the eye shape parameter .
The threshold calculation formula is: A phakic intraocular lens selection device according to claim 1, which is used for patients who have undergone phakic intraocular lens implantation, and is derived based on the preoperative angle opening obtained from cases judged to have a narrow angle based on pre-set judgment criteria, and the distance obtained from the said cases.
The phakic intraocular lens selection device according to claim 2, wherein the judgment criterion is that , in a plurality of regions obtained by virtually dividing the entire circumference of the eye of a patient who has undergone phakic intraocular lens implantation at a predetermined central angle , at least one region is judged to have a narrow angle.
The acquisition unit further acquires the postoperative angle opening from patients who have undergone phakic intraocular lens implantation surgery. A reference value for narrow corner angles is set in advance. The entire circumference of the eye of the patient who has undergone the aforementioned phakic intraocular lens implantation surgery is virtually divided into multiple regions at a predetermined central angle, The reference value for the narrow corner angle is set for each of the multiple regions. The phakic intraocular lens selection device according to claim 2, wherein the judgment criterion is set to determine that the angle is narrow if there is a region in at least one of the multiple regions where the postoperative angle opening is smaller than the corresponding reference value for the narrow angle.
A step to obtain at least the preoperative angle of ocular shape parameters from patients who have undergone intraocular lens implantation, A calculation step to calculate a threshold for the distance that serves as an indicator of a narrow angle, based on a predetermined threshold calculation formula, using the preoperative angle opening obtained in the acquisition step, with the preoperative angle opening and the distance from the anterior surface of the phakic intraocular lens to the posterior surface of the phakic intraocular lens in a patient who has undergone phakic intraocular lens implantation as variables, and using the preoperative angle opening obtained in the acquisition step, The computer is instructed to perform a selection step, which involves selecting the lens size of the intraocular lens for a phakic eye by referring to the distance threshold calculated in the calculation step , The selection step is a phakic intraocular lens selection program that selects a lens size for a phakic intraocular lens that corresponds to a predicted distance smaller than the distance threshold calculated in the calculation step, by referring to a lens size selection table for phakic intraocular lenses that is set in advance in accordance with the predicted distance calculated based on the eye shape parameters .
The threshold calculation formula is: A phakic intraocular lens selection program according to claim 5, which is derived based on the preoperative angle opening obtained from cases judged to have a narrow angle based on pre-set judgment criteria, and the distance obtained from the said cases, for patients who have undergone phakic intraocular lens implantation surgery.
The phakic intraocular lens selection program according to claim 6 , wherein the judgment criterion is that, in a plurality of regions obtained by virtually dividing the entire circumference of the eye of the patient who has undergone phakic intraocular lens implantation surgery by a predetermined central angle , at least one region is judged to have a narrow angle.
In the aforementioned acquisition step, the postoperative angle of view is further obtained from patients who have undergone intraocular lens implantation surgery. A reference value for narrow corner angles is set in advance. The entire circumference of the eye of the patient who has undergone the aforementioned phakic intraocular lens implantation surgery is virtually divided into multiple regions at a predetermined central angle, The reference value for the narrow corner angle is set for each of the multiple regions. The phakic intraocular lens selection program according to claim 6, wherein the judgment criterion is set to determine that the angle is narrow if there is a region in at least one of the multiple regions where the postoperative angle opening is smaller than the corresponding reference value for the narrow angle.

Description

Applicable to Article 30, Paragraph 2 of the Patent Law. Abstracts of the 79th Annual Meeting of the Japanese Society of Clinical Ophthalmology, "Why?! >>> Intellectual Curiosity," published September 26, 2025. https://convention.jtbcom.co.jp/79ringan/index.html General Presentation 20, 79th Annual Meeting of the Japanese Society of Clinical Ophthalmology, October 9, 2025, Rihga Royal Hotel Osaka The present invention relates to a phakic intraocular lens selection device and a phakic intraocular lens selection program. Patent Document 1 (described below) discloses a method for automatically estimating the vault (distance from the anterior surface of the crystalline lens to the posterior surface of the phakic intraocular lens) after intraocular contact lens implantation surgery, based on OCT (optical coherence tomography) images acquired postoperatively, using a computer trained with the patient's past corneal refractive surgery history. Furthermore, Non-Patent Document 1 (listed below) discloses a method for predicting the vault after intraocular lens implantation using a computer-based learning model, based on ocular shape parameters before the procedure. Incidentally, if the vault value is too low, it may lead to cataracts caused by, for example, contact trauma. On the other hand, if the value is too high, it may lead to a narrow angle postoperatively, increased intraocular pressure, and ultimately, angle-closure glaucoma. Non-patent document 1 below suggests that a vault range of 0.25 to 0.75 mm is generally desirable to avoid the above risks. In current intraocular lens implantation procedures, for example, the vault is predicted using the method described in Non-patent document 1 below, and the lens size of the intraocular lens is selected so that the predicted value falls within the above range. Specifically, it is common to select the lens size corresponding to the predicted vault value closest to a predicted vault value of 0.50 mm. International Publication No. 2024/036140 Di Y et al. Translational Vision Science $ Technology 2024 Jan 15, 13(1):8. Predicting Implantable Collamer Lens Vault Using Machine Learning Based on Various Preoperative Biometric Factors A block diagram of apparatus 1 to which an ICL (intraocular lens with phakic) selection device according to one embodiment of the present invention is applied.A flowchart showing the sequence of processes executed by the calculation unit in Figure 1.A flowchart showing the procedure for creating the threshold calculation formula used in the S2 process in Figure 2.An explanatory diagram showing eye shape parameters (hACD, hATA, hCLR).An explanatory diagram showing eye shape parameters (vACD, vATA, vCLR).An explanatory diagram showing the eye shape parameter (LT).An explanatory diagram showing ocular shape parameters (preoperative AOD (preoperative angle of diopter)).An explanatory diagram showing vault (distance).(a) is an explanatory diagram showing an example of an open-angle eye (healthy eye). (b) is an explanatory diagram showing an example of a narrow-angle eye (closed-angle eye).An explanatory diagram showing the angle of the eye in each of the 32 divided regions around the entire circumference of the eye.(a) is a graph showing the relationship between preoperative AOD and vault in the Open group. (b) is a graph showing the relationship between preoperative AOD and vault in the Narrow group.(a) is an explanatory diagram showing an example of threshold calculation (right eye). (b) is an explanatory diagram showing an example of threshold calculation (left eye).(a) is an explanatory diagram showing the selection of ICL corresponding to Figure 12(a). (b) is an explanatory diagram showing the selection of ICL corresponding to Figure 12(b).(a) is an explanatory diagram showing the postoperative angle condition corresponding to Figure 13(a). (b) is an explanatory diagram showing the postoperative angle condition corresponding to Figure 13(b). (Embodiment) Hereinafter, one embodiment of the present invention will be described with reference to the drawings. Figure 1 shows a block diagram of apparatus 1 to which the phakic intraocular lens selection device according to the present invention is applied. Apparatus 1 selects the lens size of a phakic intraocular lens (ICL®, hereinafter referred to as ICL) based on various eye shape parameters. An ICL is a posterior chamber type phakic intraocular lens that is inserted in front of the lens and behind the iris by ICL insertion surgery (hereinafter referred to as ICL insertion surgery, with the period before surgery being referred to as pre-surgery and the period after surgery being referred to as post-surgery) to correct myopia or astigmatism. The apparatus 1 comprises an imaging unit 2, an input unit 3, a display unit 4, and a calculation unit 5. The imaging unit 2 is, for example, an OCT (Optical Coherence Tomography) device. An OCT device is a well-known optical instrument that captures cross-sectio