DESC:A SYSTEM WITH 3D OVERLAY MARKING SCALE FOR SQUINT CORRECTION PROCEDURE AND A METHOD THEREOF

FIELD OF INVENTION
The present invention relates generally to the field of ophthalmology, particularly to system and method for non contact measurements on human eye while performing a squint surgery. More particularly, the present invention relates to a system with 3D overlay marking scale for squint correction procedure and a method thereof.

BACKGROUND OF INVENTION
In general, a squint or strabismus occurs when the eyes are not aligned in the same direction. Mostly children get impacted by squint eyes, and it can be constant or intermittent, but it can occur at any age. Most strabismus is the results of an abnormality of the neuromuscular control of eye movement. Squint may lead to vision problems if not treated early as observed. If left untreated, there are chances of vision loss as well. To repair squint, the eye muscles are operated on to correct the imbalance in them. Children generally undergo the squint procedure under general anesthesia, such that they are sleeping throughout the procedure. Adults may be given local anesthesia to only numb the region around the eye. The surgeon makes a small incision in the conjunctiva of patient eye and approaches the patient eye muscles to stretch them or shorten them correctly positioning the eye. The opening in the conjunctiva may or may not be sutured. This process is repeated for each muscle that is operated on. Further all squint surgeries were performed with calculations and exact measured suturing of the related muscles to achieve an exact correction for that particular eye. For this reason the ophthalmic surgeons use marker pens, calipers to mark the suturing location as per the calculation done.

CN115953717A discloses a method and a device for measuring an eye position deflection angle based on three-dimensional reconstruction.

KR102224209B1 discloses an apparatus and method for measuring a deviation angle, the apparatus comprising an image display unit for displaying a 3D target image including a target; An eye photographing unit for photographing an eyeball of a subject gazing at the 3D target image; For the first eyeball of the 3D target image and the reference image photographed of the first eye of the test subject while blocking the second image displayed for the second eye of the test subject among the 3D target images A gaze tracking unit configured to determine a gaze position of the first eyeball in each of the comparison images taken of the first eyeball while blocking the displayed first image; It is determined whether the gaze position of the first eyeball in the comparison image and the reference image coincide, and if not, the gaze position of the first eyeball in the comparison image is the gaze position of the first eyeball in the reference image An image control unit for moving the position of the target until it coincides with; And a bevel angle determining unit for determining a bevel based on an initial position and a final position of the target, when the position of the first eyeball in the comparison image coincides with the position of the first eyeball in the reference image.

CN115281931A discloses an ophthalmic strabismus correction device and a correction method thereof. The device includes spectacle-frame, the diaphragm, interval adjustment mechanism, control adjustment mechanism and upper and lower adjustment mechanism, the quantity of spectacle-frame is two sets of and is about the distribution setting, the inner wall of spectacle-frame is provided with the lens, the rear side of lens is provided with the centering piece, be provided with the rectangle piece between two sets of spectacle-frame frames and be two sets of rectangle posts that distribute from top to bottom, the bottom of two sets of spectacle-frame frames is provided with the bridge of the nose frame board, be provided with the connecting block on the spectacle-frame, the front side of lens is pasted and is fixed with the scale label, the diaphragm sets up in the top of two sets of spectacle-frame frames, the bottom of diaphragm is provided with two sets of risers.

CN112336301A provides an oblique vision measuring apparatus, including a display and control module; an image shooting and processing module; a calibration module; an eye movement point calculation module; and a data analysis module. The invention has the beneficial effects that: the time of doctors and examinees can be effectively saved, qualitative and quantitative squint measurement results can be quickly obtained, and the test results are visual and accurate.

CN104799998B discloses a kind of optics strabismus correcting instrument comprising a pair rotating link the application strabismus correcting instrument housing side, two strabismus correcting instrument housings are connected by connecting shaft, there is ocular lenses seat the rear end of strabismus correcting instrument housing side, ocular lenses seat has ocular lenses in end, there is objective lens eyeglass seat the front end of strabismus correcting instrument housing opposite side, objective lens eyeglass seat has objective lens eyeglass in end, a pair revolving mirror eyeglass is had in strabismus correcting instrument housing, revolving mirror eyeglass is in revolving mirror eyeglass seat, there is fixing end revolving mirror eyeglass seat upper end, angled knob on the fixing end of revolving mirror eyeglass seat.

The following are the limitations or drawbacks of existing squint correction procedures: Ink marking is required, pooling of blood during the squint surgery will tend to erase the markings made with the inked instruments so repeated marking is made which might induce an error. Physical markings with the ophthalmic calipers induce marks on the eye and slips due to the wet zone. Sometimes repeat surgeries may require if there is a correction required on the same eye if the muscles were not sutured at the intended point on the patient for a perfect squint correction.

Accordingly, there exists a need for a system with 3D overlay marking scale for squint correction procedure which enhances accuracy level of the squint correction as well as minimizes overall surgical time involved.

OBJECTS OF INVENTION
One or more of the problems of the conventional prior art may be overcome by various embodiments of the system and method of the present invention.

It is the primary object of the present invention to provide a system with 3D overlay marking scale for squint correction procedure which enhances accuracy level of the squint correction as well as minimizes overall surgical time involved.

It is another object of the present invention to provide a system that facilitates a video overlay of a measuring scale digitally superimposed on the eye to be operated for squint correction.

It is another object of the present invention, wherein the system provides 3D overlay reference scale as an indicator for muscle insertion on the human eye while performing a squint surgery.

It is another object of the present invention to provide a system for squint correction procedure, comprising of:
a 3D camera module mounted on an existing ophthalmic microscope;
a 3D monitor with a computing device;
a foot switch; and
a 3D goggles.

It is another object of the present invention, wherein the system provides exact measurement as required by the ophthalmic surgeon that could be visually guided and indicated by unique graduated scales in “mm” appearing on the 3D monitor as a video overlay which visually guides the surgeon on the exact dimensions required for the related muscles to be sutured.

SUMMARY OF INVENTION
Thus the basic aspect of the present invention is to provide a system with 3D overlay marking scale for squint correction procedure, comprises of:
a 3D camera module mounted on an ophthalmic microscope;
a 3D monitor with a computing device;
a foot switch; and
3D goggles,
wherein the 3D camera module comprises of:
a focus knob stem;
a prism housing;
two focusing lenses;
two charged coupled device (CCD) cameras; and
a reflecting mirror,
wherein right and left image focused by the focusing lens is reflected at 45 degrees on both the charged coupled device (CCD) cameras by using the reflecting mirror to create a continuous 3D video by generating a continuous right and left images,
wherein the 3D video output from the 3D camera module is transmitted to the 3D monitor,
wherein two reference scales indication is seen on the left and right images to create a 3D overlay of the measuring scale on the 3D eye image,
wherein the two left and right images is viewed as a single image through the 3D goggles on the 3D monitor with the squint max marking scale overlayed by the computing device in the 3D monitor, and
wherein the system facilitates a video overlay of an inkless or a marker less measuring scale digitally superimposed on an eye in real time viewed as a continuous 3D video.

It is another aspect of the present invention, wherein the system provides exact measurement as required which is visually guided and indicated by graduated measuring scales in “mm” appearing on the 3D monitor as a video overlay.

It is another aspect of the present invention, wherein the measuring scales from 1 to 8mm graduations in steps of 0.5mm and 1 to 10mm graduations in steps of 0.5mm is overlayed over the image obtained using the 3D camera module.

Another aspect of the present invention is to provide a method of providing 3D overlay marking scale for squint correction procedure using the system, comprising steps of:
focusing image falling on the prism housing through the focusing lenses of the 3D camera module mounted on an ophthalmic microscope;
reflecting of the focused right and left image at 45 degrees on both the right and left CCD cameras by using the reflecting mirror to create a 3D video by generating a continuous right and left images;
transmitting 3D video output from the 3D camera module to the 3D monitor;
focusing human eye in the ophthalmic microscope using the footswitch;
overlaying two reference scales indication on the left and right images to fuse and create a 3D overlay of a single measuring scale on the 3D image of the eye;
viewing the left and right images as a single image through the 3D goggle on the 3D monitor with the squint max marking scale overlayed by the computing device in the 3D monitor;
facilitating a video overlay of an inkless or a marker less measuring scale digitally superimposed on an eye in real time with a 3D depth of focus; and
providing exact measurement as required which could be visually guided and indicated by graduated measuring scales in “mm” appearing on the 3D monitor as a video overlay.

BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1: illustrates a system with 3D overlay marking scale for squint correction procedure according to present invention.
Figure 2: illustrates a 3D camera module attached to a microscope head according to present invention.
Figure 3: illustrates inner assembly of the 3D camera module according to present invention.
Figure 4: illustrates viewing of 3D overlay squint max scale reference indication on the human eye in the 3D monitor according to present invention.
Figure 5: illustrates accurate measurement scale for an oblique muscle suturing measured with a digital vernier when the oblique scale is overlayed over a model eye according to present invention.
Figure 6: illustrates superior inferior lateral nasal overlay for squint correction procedure according to present invention.
Figure 7: illustrates inferior overlay for squint correction procedure according to present invention.
Figure 8: illustrates superior overlay for squint correction procedure according to present invention.
Figure 9: illustrates right eye lateral / left eye nasal overlay for squint correction procedure according to present invention.
Figure 10: illustrates right eye nasal / left eye lateral overlay for squint correction procedure according to present invention.
Figure 11: illustrates superior inferior overlay for squint correction procedure according to present invention.
Figure 12: illustrates left eye right eye lateral overlay for squint correction procedure according to present invention.
Figure 13: illustrates superior inferior oblique overlay for squint correction procedure according to present invention.
Figure 14: illustrates inferior oblique overlay for squint correction procedure according to present invention.
Figure 15: illustrates superior oblique overlay for squint correction procedure according to present invention.

DETAILED DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING FIGURES
The present invention as herein described relates to a system with 3D overlay marking scale for squint correction procedure which enhances accuracy level of the squint correction as well as minimizes overall surgical time involved.

Referring to Figures 1 to 3, the system [100] with 3D overlay marking scale for squint correction procedure comprises of a 3D camera module [1] mounted on an existing ophthalmic microscope [2]; a 3D monitor [3] with a computing device; a foot switch [4]; and 3D goggles [5]. The 3D camera module [1] comprises of a focus knob stem [1a]; a prism housing [1b]; two focusing lenses [1c]; two charged coupled device (CCD) cameras [1d]; and a reflecting mirror [1e]. The focus knob stem [1a] is used for adjusting the focus simultaneously of the twin charged coupled device (CCD) cameras [1d] for the perfect creation of 3D image of the eye. The focusing lenses [1c] are used to focus the image falling on the prism housing [1b]. The focused image [right and left image] [1f] is reflected at 45 degrees on both the cameras [right and left camera] by using the 45° reflecting mirror [1e] to create a continuous 3D video by generating a continuous right and left images. The 3D image output from the 3D camera module [1] is then transmitted by a cable which is connected to the 3D monitor [3] through its video input socket. An ophthalmic observer could see two reference scales indication on the left and right images [1f]. The ophthalmic observer could see reference scale indication on the human eye through the 3D goggles [5] as a single image in the 3D monitor [3] with the squint max marking scale overlayed with a perfect depth of focus for squint surgery without any ink markings on the eye surface and with very less instrumentation manipulation on the eye. The system thus facilitates a video overlay of an inkless or a marker less measuring scale digitally superimposed on an eye in real time viewed as a continuous 3D video.

Working with illustration:
Referring to Figures 1 to 3, the system [100] with 3D overlay marking scale for squint correction procedure comprises of a 3D camera module [1] mounted on an ophthalmic microscope [2]; a 3D monitor [3] with a computing device; a foot switch [4]; and 3D goggles [5]. The 3D camera module [1] comprises of a focus knob stem [1a]; a prism housing [1b]; two focusing lenses [1c]; two charged coupled device (CCD) cameras [1d]; and a reflecting mirror [1e]. The focus knob stem [1a] is used for adjusting the focus simultaneously of the twin CCD cameras [1d] for the perfect creation of 3D image of the eye. The focusing lenses [1c] are used to focus the image falling on the prism housing [1b]. The focused image [right and left image] [1f] is reflected at 45 degrees on both the CCD cameras [right and left camera] [1d] by using the 45° reflecting mirror [1e] to create a continuous 3D video by generating a continuous right and left images. The ophthalmic observer focuses the human eye in the existing ophthalmic microscope [2] using the footswitch [4]. The ophthalmic observer could see two reference scales indication on the left and right images [1f] to fuse and create 3D overlay of a single measuring scale on the 3D image of the eye. When the observer wears the 3D goggles [5], the left and right images [1f] separately visualized by the left eye and right eye of the observer fuses or combines as a single image in the observer’s optical chiasma of the brain while viewing straight on the 3D monitor [3] with the squint max scale overlayed by the computing device [3]. The observer can see the 3D overlay squint max scale reference indication on the human eye in the 3D monitor [3] with a perfect depth of focus for squint surgery as shown in Figure 4. The 3D overlay reference scale facilitates as an indicator for muscle insertion on the human eye while performing a squint surgery. It minimizes time taken for each eye surgery as most of the squint surgeries are done on pediatric patients under general anesthesia hence this 3D visual guidance enhances accuracy level of the squint correction as well as minimizes overall surgical time involved. Figure 5 shows the accurate measurement scale for an oblique muscle suturing measured as compared with a digital vernier when the oblique scale is overlayed over a model eye.

The system provides exact measurement as required by the ophthalmic surgeon that could be visually guided and indicated by unique graduated scales in “mm” appearing on the 3D monitor [3] as a video overlay which visually guides the Surgeon on the exact dimensions required for the related muscles to be sutured. In an aspect, the marking scale is 8mm or 10mm long with 0.5mm steps divisions. Referring to Figures 6 to 15, the exact suturing point of the muscle (superior rectus, inferior rectus, lateral rectus, nasal and oblique muscles) over the sclera could be identified using the guided 3D overlay scales which enable the surgeon to position the muscle to that required measurement as indicated by the divisions on the scales [6c, 6c’, 6d, and 6d’] as 1mm, 1.5mm, 2mm, 2.5mm ….. 10mm as per the calculation made for the squint correction of that particular eye of the Patient. The horizontal reference lines (180°) are indicated by [6a and 6a’] and the vertical reference lines (90°) are indicated by [6b and 6b’]. One overlay of the measuring sale is positioned to be over the Limbus as a initial point of reference from where the graduations of the scale indicates the second point of reference wherein exactly the suture needle for a muscle recession is passed to stitch the targeted Rectus muscle for squint correction of that particular eye under consideration without any ink markings on the sclera or using multiple caliper or forceps instruments.Thus the observer observes the 3D monitor [3] while performing the muscle recession and suturing during a squint surgery and there is an accurate visual guidance with regard to as where the exact point as per the calculation to place the tip of the suture needle to accurately correct the squint post surgery.

Technical advancements:
No ink marking required.
No contact of sharp caliper instruments on the eye surface.
Measurement errors due to instrument handling and its tip thickness are avoided completely.
3D visual guidance enhances accuracy level of the squint correction as well as minimizes overall surgical time involved for each eye.
Perfect squint correction could be achieved in a single sitting procedure.
,CLAIMS:WE CLAIM:
1. A system [100] with 3D overlay marking scale for squint correction procedure comprises of:
a 3D camera module [1] mounted on an ophthalmic microscope [2];
a 3D monitor with a computing device [3];
a foot switch [4]; and
3D goggles [5],
wherein the 3D camera module [1] comprises of:
a focus knob stem [1a];
a prism housing [1b];
two focusing lenses [1c];
two charged coupled device (CCD) cameras [1d]; and
a reflecting mirror [1e],
wherein right and left image [1f] focused by the focusing lens [1c] is reflected at 45 degrees on both the charged coupled device (CCD) cameras [1d] by using the reflecting mirror [1e] to create a continuous 3D video,
wherein the 3D video output from the 3D camera module [1] is transmitted to the 3D monitor [3],
wherein two reference scales indication is overlayed on the left and right images [1f] to create a 3D overlay of the measuring scale on the 3D eye image,
wherein the two left and right images [1f] is viewed as a single image through the 3D goggles [5] on the 3D monitor [3] with the squint max marking scale overlayed by the computing device in the 3D monitor [3], and
wherein the system facilitates a video overlay of an inkless or a marker less measuring scale digitally superimposed on an eye in real time viewed as a continuous 3D video.

2. The system [100] with 3D overlay marking scale for squint correction procedure as claimed in claim 1 provides exact measurement as required which is visually guided and indicated by graduated measuring scales in “mm” appearing on the 3D monitor [3] as a video overlay.

3. The system [100] with 3D overlay marking scale for squint correction procedure as claimed in claim 2, wherein the measuring scales from 1 to 8mm graduations in steps of 0.5mm and 1 to 10mm graduations in steps of 0.5mm is overlayed over the image [1f] obtained using the 3D camera module [1].

4. A method of providing 3D overlay marking scale for squint correction procedure using the system as claimed in claim 1, comprising steps of:
focusing image falling on the prism housing [1b] through the focusing lenses [1c] of the 3D camera module [1] mounted on an ophthalmic microscope [2];
reflecting of the focused right and left image [1f] at 45 degrees on both the right and left CCD cameras [1d] by using the reflecting mirror [1e] to create a continuous 3D video by generating a continuous right and left images;
transmitting of 3D video output from the 3D camera module [1] to the 3D monitor [3];
focusing human eye in the ophthalmic microscope [2] using the footswitch [4];
overlaying two reference scales indication on the left and right images [1f] to fuse and create a 3D overlay of a single measuring scale on the 3D image of the eye;
viewing the left and right images [1f] as a single image through the 3D goggles [5] on the 3D monitor [3] with the squint max marking scale overlayed by the computing device in the 3D monitor [3];
facilitating a video overlay of an inkless or a marker less measuring scale digitally superimposed on an eye in real time with a 3D depth of focus; and
providing exact measurement as required which could be visually guided and indicated by graduated measuring scales in “mm” appearing on the 3D monitor [3] as a video overlay.