JP4992051B2 - Prescription contact lens selection device for corneal orthodontic therapy - Google Patents

Description

  The present invention relates to an apparatus for selecting a prescription contact lens for corneal orthodontic therapy, and more particularly, a prescription contact lens for corneal orthodontic therapy capable of selecting a prescription contact lens that provides optimal fitting based on the wearing result of a trial contact lens. Relates to the selection device.

  In recent years, corneal correction therapy (also called orthokeratology) has attracted attention as a treatment method for correcting myopia. Cornea orthodontic therapy is a state in which a cornea is deformed along the shape of the contact lens by wearing a specially shaped hard contact lens with high oxygen permeability during sleep, and the cornea is deformed for a certain period of time even after the contact lens is removed. It is intended to correct the refractive error by keeping

As a method of selecting a contact lens for corneal orthodontic therapy, the fitting result of the trial contact lens, specifically, fitting is evaluated by fluorescein staining. If the fitting is not good, a contact lens with an approximate value parameter is selected and fitting evaluation is performed. Has been proposed to determine the optimum trial contact lens (for example, see Patent Document 1).
JP 2007-255 A (Claims Claims 1, paragraphs 0009, 0014, FIG. 2)

  However, in the contact lens selection method, the idea of evaluating the fitting at the time of selecting the contact lens can be evaluated, but if the fitting is not good, it is necessary to select the contact lens of the approximate parameter and repeat the fitting evaluation. In some cases, it may be necessary to wear trial contact lenses many times before the optimal contact lens is determined, and the selection of the contact lens is complicated.

  Therefore, in the present invention, a prescription that solves the above-mentioned problems and finds a tendency of the contact lens shape that can improve the fitting from the wearing result of the trial contact lens, and uniquely provides an optimal fitting without trial and error. It is an object of the present invention to provide a prescription contact lens selection device for orthokeratology that can select a contact lens.

  In order to solve the above-mentioned problem, in the invention according to claim 1, a prescription contact lens selection device for corneal correction therapy, an input device for inputting the shape of the trial contact lens and the state of the fluorescein pattern when the trial contact lens is worn, A storage device that memorizes the shape of the trial contact lens input by the input device, and when the fluorescein pattern input by the input device is shifted from the concentric circle of the pupil to the upper eyelid side, the alignment curve is larger than that of the trial contact lens. A selection device that selects a tight contact lens as a prescription contact lens, and selects a contact lens with a looser alignment curve than the trial contact lens when the fluorescein pattern is shifted from the concentric circle of the pupil to the lower eyelid side With this selection device Configured as an output device and for outputting the shape of the constant prescription contact lenses.

  In the invention according to claim 2, the selection device is configured to align the alignment curve more than the trial contact lens when the alignment curve pattern width is narrower than the reverse curve pattern width even when the fluorescein pattern is on the concentric circle of the pupil. A loose contact lens was selected as a prescription contact lens.

  In the invention according to claim 3, when the prescription contact lens is not worn during sleep, the contact lens having a looser alignment curve than the prescription contact lens selected by the prescription contact lens selection device for corneal correction therapy is used as the prescription contact. It was selected as a lens.

  According to the first aspect of the present invention, when the fluorescein pattern is deviated from the concentric circle of the pupil, the contact lens having a shape capable of improving the fitting corresponding to the deviated direction is selected as the prescription contact lens. Therefore, it is possible to select a prescription contact lens for orthokeratology that provides a uniquely optimal fitting without trial and error.

  According to the invention of claim 2, even when the fluorescein pattern is on the concentric circles of the pupil, the shape that can improve the fitting corresponding to the case where the alignment curve pattern width is narrower than the reverse curve pattern width. Since the contact lens is selected as the prescription contact lens, it is possible to select a prescription contact lens for corneal correction therapy that provides a uniquely more stable fitting without trial and error.

  According to the invention of claim 3, since the contact lens having a shape corresponding to the case where the prescription contact lens is not worn during sleep is selected as the prescription contact lens, the awakening is different from the case where the prescription contact lens is worn during general sleep. A prescription contact lens for orthokeratological therapy that meets the wearing conditions, such as wearing the occasional wear lens and removing the contact lens when necessary, such as when playing sports, can be selected.

First, the matter which becomes the foundation of creation of this invention is demonstrated with reference to FIG. 4 and FIG.
FIG. 4A is a plan view of a contact lens for corneal correction therapy, and FIG. 4B is a cross-sectional view of the contact lens for corneal correction therapy. FIG. 5 is an image showing an ideal fluorescein pattern.

  As shown in FIGS. 4A and 4B, the corneal orthodontic contact lens 1 (hereinafter also referred to as a lens) is a rounded circular lens, and the inner surface of the lens in contact with the cornea is concentric. Are composed of four curves, specifically, a base curve 2, a reverse curve 3, an alignment curve 4, and an edge curve 5. And although the inventor selected the lens based on the inspection results such as refraction test, corneal curvature radius measurement, corneal shape analysis, correction visual acuity test, etc. that are generally performed when performing corneal correction therapy It has been found that the reason why the desired correction effect cannot be obtained is a fitting defect. The inventors have found that the fit can be judged by confirming the fluorescein pattern, and have led to the creation of the present invention.

  As shown in FIG. 5, in an ideal fluorescein pattern with a lens fitted with a good fitting, the lens pattern 1 'is positioned on the concentric circle of the pupil, and the movement due to blinking is small, and the lens pattern 1' is maintained on the concentric circle of the pupil. Has been. Then, the inventor has shown that, when the fluorescein pattern is shifted from the concentric circle of the pupil to the upper eyelid side, the fitting of the wearing lens is loose and the alignment curve 4 (FIG. It was found that fitting is improved by selecting a lens having a tight (see (b)). Furthermore, when the fluorescein pattern is shifted from the concentric circle of the pupil to the lower eyelid side, the fitting of the wearing lens is tight, and it is also found that the fitting can be improved by selecting a lens with a loose alignment curve 4. This has led to the creation of the invention according to Item 1.

  In addition, as shown in FIG. 5, in an ideal fluorescein pattern, the four curves shown in FIGS. 4A and 4B change the degree of staining depending on the degree to which the cornea is compressed and the presence or absence of compression. A ring-shaped pattern is generated, and four curves are shown as a base curve pattern 2 ′, a reverse curve pattern 3 ′, an alignment curve pattern 4 ′, and an edge curve pattern 5 ′. The inventor has found from a number of clinical trial results that when the alignment curve pattern 4 ′ width is narrower than the reverse curve pattern 3 ′ width, the fitting is stabilized by selecting a lens having a loose alignment curve 4; The invention according to claim 2 has been created.

  Furthermore, the inventor noticed that there are patients who do not wear the contact lens for corneal orthodontic therapy at the time of sleep, but wear it at the time of awakening and remove the lens when necessary, for example, when playing sports. From the clinical trial results, when wearing at awakening, select a lens whose alignment curve 4 (see FIGS. 4 (a) and 4 (b)) is slower than the lens selected for wearing at sleep. Since the movement of the lens required for wearing at the time of awakening can be secured, it was found to meet the wearing conditions such as wearing at the time of awakening and removing the lens when necessary, and the invention according to claim 3 was created. It is.

  Next, embodiments of the present invention will be described in detail with reference to the drawings as appropriate. FIG. 1 is an image diagram of a prescription contact lens selection device for corneal correction therapy according to an embodiment. As shown in FIG. 1, the prescription contact lens selection device for corneal correction therapy according to this embodiment includes an input device A, a storage device B, a selection device C, and an output device D.

  The input device A is a device that inputs the shape of the trial lens and the state of the fluorescein pattern when the trial lens is worn. Note that the input device A according to claim 3 is a device for inputting lens wearing conditions in addition to these.

  The storage device B stores the shape of the trial lens input by the input device A. Here, the specifications of the prescription lenses manufactured by each manufacturer are also stored.

  The selection device C is a device that selects, as a prescription lens, a lens having a shape that can improve the fitting according to the state of the fluorescein pattern input by the input device A. Here, the prescription lens stored in the storage device B is used. It is a device that selects the standard that brings about the best fitting from the standard of the prescription lens. In the selection device C according to the third aspect of the present invention, the prescription lens is determined based on the wearing condition of the lens input by the input device A and the standard that provides the optimum fitting that matches the wearing condition from the prescription lens standard stored in the storage device B. It is a device to select as.

  The output device D is a device that outputs the shape of the prescription lens selected by the selection device C. Here, the output device D is selected as the optimum fitting based on the prescription lens standard stored in the storage device B by the selection device C. It is a device that outputs the prescription lens standard.

  In the prescription contact lens selection device for corneal correction therapy configured as described above, the selection device C selects the shape and standard of the prescription lens that provides the optimum fitting according to the process shown in FIG. FIG. 2 is a flowchart illustrating a process performed by the selection device C according to the embodiment. As shown in FIG. 2, in the selection apparatus C, a fluorescein pattern state information acquisition step S1 and a prescription lens standard selection step S2 are performed.

  The fluorescein pattern state information acquisition step S1 is a step of acquiring state information of the fluorescein pattern when the trial lens is worn from the input device A (see FIG. 1). Here, the state information of the fluorescein pattern means the position of the lens pattern 1 ′ (see FIG. 5) with respect to the pupil, specifically on the concentric circle of the pupil, from the concentric circle of the pupil to the upper eyelid side Information on the position of being shifted from the concentric circle of the pupil to the lower eyelid side, and the pattern widths of the four curves constituting the lens 1 (see FIGS. 4A and 4B), specifically Is information that compares the widths of the reverse curve pattern 3 ′ (see FIG. 5) and the alignment curve pattern 4 ′ (see FIG. 5).

  In the fluorescein pattern state information acquisition step S1, when the state information of the fluorescein pattern is acquired, the process proceeds to the prescription lens standard selection step S2.

  The prescription lens standard selection step S2 is based on the state information of the fluorescein pattern acquired in the fluorescein pattern state information acquisition step S1, and the shape of the trial lens stored in the storage device B and the prescription manufactured by each manufacturer. This is a step of selecting, as a prescription lens, a standard that provides an optimum fitting while referring to the lens standard.

  In the prescription lens standard selection step S2, in the step of identifying the position of the lens pattern 1 ′ (S2a), when the lens pattern 1 ′ is located on the concentric circle (hereinafter referred to as the center) of the pupil (Yes), It progresses to the process (S2b) which identifies the width | variety of a pattern. On the other hand, when the lens pattern 1 'is not in the center (No), the process proceeds to the step of identifying the shifted direction (S2c).

  When the alignment curve pattern 4 ′ width is not narrower than the reverse curve pattern 3 ′ width in the step of identifying the pattern width (S2b) (No), in other words, the alignment curve pattern 4 ′ width is the same as the reverse curve pattern 3 ′ width. Alternatively, if the width of the reverse curve pattern 3 ′ is wider, a standard having the same shape as the trial lens is selected as the prescription lens (S2d), and the process performed by the selection device C is completed. On the other hand, when the alignment curve pattern 4 ′ width is narrower than the reverse curve pattern 3 ′ width (Yes) in the step of identifying the pattern width (S2b) (Yes), the standard that the alignment curve 4 is looser than the trial lens is used as the prescription lens. Select (S2e), and the process performed by the selection device C is completed.

  Also, in the prescription lens standard selection step S2, when the lens pattern 1 ′ is shifted from the concentric circle of the pupil to the upper eyelid side in the step (S2c) of identifying the shifted direction of the lens pattern 1 ′ (Yes), A standard having a tighter alignment curve 4 than the trial lens is selected as a prescription lens (S2f), and the process performed by the selection device C is completed. On the other hand, when the lens pattern 1 ′ is displaced from the concentric circle of the pupil to the lower eyelid side (No) in the step (S2c) of identifying the direction in which the lens pattern 1 ′ is displaced, the alignment curve 4 is more than that of the trial lens. A loose standard is selected as a prescription lens (S2g), and the process performed by the selection device C is completed.

  In the prescription contact lens selection method for corneal correction therapy according to claim 6, in the selection device C (see FIG. 1), following the process shown in FIG. 2, a lens wearing condition information acquisition process S11 and a prescription lens standard selection process S12 are performed. Done. FIG. 3 is a flowchart showing a process performed by a selection device according to another embodiment.

  In the lens wearing condition information acquisition step S11, the lens wearing conditions, specifically, wearing condition information such as whether the lens is to be worn during sleep or whether it is worn during awakening are obtained, and the process proceeds to a prescription lens standard selection step S12.

  In the prescription lens standard selection step S12, in the step of identifying the wearing condition of the lens (S12a), when wearing the lens during sleep (Yes), a standard having the same shape as the lens selected by the step shown in FIG. It selects as a prescription lens (S12b), and the process performed with the selection apparatus C is complete | finished. On the other hand, when wearing a lens at awakening (No), the prescription lens is a standard whose alignment curve 4 (see FIGS. 4A and 4B) is looser than the lens selected by the process shown in FIG. Select (S12c), and the process performed by the selection device C is completed.

  In the present invention, tightening the curve means changing the contact lens curve to be smaller than the cornea curve, that is, changing the direction of the contact lens to be tighter to the cornea, and loosening it means the opposite. In addition, it is preferable to adjust the degree of tightness of the curve as appropriate, but if a trial lens is selected based on the results of tests generally performed when performing corneal correction therapy, it will be included in the prescription lens specification table. According to this, 1 unit should be tightened.

  An alignment curve is a part that plays a role in stabilizing the position of the lens by contacting the part almost parallel to the cornea, and the part may consist of multiple curves of different sizes. Is sometimes called an alignment zone.

It is an image figure of the prescription contact lens selection apparatus for corneal correction therapy which concerns on embodiment. It is the flowchart figure which showed the process performed with the selection apparatus which concerns on embodiment. It is the flowchart figure which showed the process performed with the selection apparatus which concerns on other embodiment. (A) is a top view of the contact lens for corneal correction therapy, (b) is sectional drawing of the contact lens for corneal correction therapy. It is the image figure which showed the ideal fluorescein pattern.

S1 fluorescein pattern state information acquisition step S2 prescription lens standard selection step S11 lens wearing condition information acquisition step S12 prescription lens standard selection step

Claims (3)

In a device for selecting prescription contact lenses for corneal orthodontic therapy,
An input device for inputting the shape of the trial contact lens and the state of the fluorescein pattern when the trial contact lens is worn;
A storage device for storing the shape of the trial contact lens input by the input device;
When the fluorescein pattern input by the input device is shifted from the concentric circle of the pupil to the upper eyelid side, a contact lens having a tighter alignment curve than the trial contact lens is selected as a prescription contact lens,
A selection device for selecting a contact lens having a looser alignment curve than the trial contact lens as a prescription contact lens when the fluorescein pattern is shifted from the concentric circle of the pupil to the lower eyelid side;
A prescription contact lens selection device for corneal correction therapy, comprising: an output device that outputs the shape of the prescription contact lens selected by the selection device.   Even if the fluorescein pattern is on the concentric circle of the pupil, the selection device prescribes a contact lens having a looser alignment curve than the trial contact lens if the alignment curve pattern width is narrower than the reverse curve pattern width. The prescription contact lens selection device for corneal correction therapy according to claim 1, wherein the contact lens is selected as a contact lens.   When the selection device does not wear the prescription contact lens during sleep, the contact lens has a looser alignment curve than the prescription contact lens selected by the prescription contact lens selection device for corneal correction therapy according to claim 1 or 2. The prescription contact lens selection apparatus for corneal orthodontic therapy according to claim 1 or 2, wherein the prescription contact lens is selected as a prescription contact lens.

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