CN114613240B

CN114613240B - Processing method of anterior capsule of isolated pig eyeball and capsulorhexis training model for cataract operation

Info

Publication number: CN114613240B
Application number: CN202110906735.0A
Authority: CN
Inventors: 裴雅婧; 马科
Original assignee: Beijing Tongren Hospital
Current assignee: Beijing Tongren Hospital
Priority date: 2021-08-09
Filing date: 2021-08-09
Publication date: 2023-07-14
Anticipated expiration: 2041-08-09
Also published as: CN114613240A

Abstract

The invention provides a method for treating an isolated pig eyeball anterior capsule, which is characterized in that the isolated pig eyeball anterior capsule is treated by sodium hypochlorite solution with proper concentration, and the obtained pig eyeball anterior capsule has similar mechanical characteristics with the human eye anterior capsule, and can better simulate the experience of cataract operation during continuous annular capsulorhexis. The invention also provides a cataract operation capsulorhexis training model prepared by the processing method, and cataract operation beginners can use the model to carry out cataract operation continuous annular capsulorhexis training and can also be used for evaluating ophthalmic operation robot capsulorhexis operation.

Description

Processing method of anterior capsule of isolated pig eyeball and capsulorhexis training model for cataract operation

Technical Field

The invention belongs to the technical field of medicine, and relates to a method for processing an in-vitro pig eyeball anterior capsule and a training model of a white internal obstacle operation capsulorhexis.

Background

Surgical removal is the only effective treatment for cataract at present, the most popular surgical procedure for cataract surgery today is phacoemulsification, wherein continuous annular capsulorhexis is the most critical step recognized by experts, and a prospective study of Mohanna Al-Jindan et Al considers capsulorhexis as one of the most difficult steps to learn in cataract surgery, the highest complication rate step in all surgical steps, which is 40%. Huang Ai duckweed was found to have a success rate of only 86.7% when analyzed on 300 cases of cataract continuous annular capsulorhexis. And even if the capsulorhexis is performed by the same skilled practitioner, there is a large difference in the size and shape of the capsulorhexis.

Many researchers at home and abroad build simple and effective cataract animal models and provide models for cataract surgeons to train operation techniques. Such cataract models are typically built on fresh, ex vivo porcine eyeballs that are readily available and inexpensive. Takeshi Sugiura et al found that injection of the lens via the corneoscleral limbus using 0.2ml of the mixed reagent (Fulmalin, ethanol and isopropanol in a ratio of 4:3:3) was able to induce cataracts in porcine eyes. The fresh isolated pig eyeball is heated for 20 seconds by using a 800W microwave oven to manufacture a cataract model with a lens turbidity and a capsulorhexis success rate close to the clinical success rate of a practitioner, but 23.3 percent of cornea transparency is reduced, so that an operation field is blurred, the exercise difficulty is improved, and 3.3 percent of pig eyes cannot be used for exercise due to severe cornea turbidity. Xingcao et al reduced 38% formaldehyde and 100% methanol to 2:1, injecting the mixture to the surface of an anterior capsule through a main cornea incision on an isolated pig eyeball, then injecting 0.2mL of the mixed reagent under the anterior capsule, and heating by a combined microwave oven to obtain a model of the cataract with clear cornea, reduced tension and elasticity of the anterior capsule and hardened crystalline nucleus. Robert William randomly divides the isolated pig eyeballs into two groups, and respectively carries out microwave treatment and chemical reagent treatment to manufacture a cataract model. The microwave treated group lens became cloudy but the anterior chamber became shallow and the anterior capsule remained highly elastic, which was detrimental to capsulorhexis training. The chemical treatment group may fuse the cortex to the capsule, which is detrimental to water separation. In summary, none of the models is capable of very well simulating the experience of a cataract surgery in a continuous annular capsulorhexis.

Evaluation of this type of cataract animal model focused on evaluation of the degree of turbidity of its lens. The model is helpful for the surgeon to practice nucleus splitting technology, the doctor to master and understand the shape and size of the crystalline lens. However, such models are relatively negligible in evaluating hand at capsulorhexis. The anterior capsule of the porcine eyeball has a tougher texture compared with the anterior capsule of the human white internal obstacle, the capsulorhexis hand feeling is completely different, the Sueiras et al observe that the surface of the anterior capsule of the human lens is obviously coarser than that of the porcine under an atomic force microscope, and the roughness of the anterior capsule of the human lens is obviously increased along with the age. In the prior cataract operation beginner, when performing continuous annular capsulorhexis exercise, a low-age pig eyeball from a meat-linked factory which is easy to obtain is usually used, the difference between the front capsule of the low-age pig and the front capsule of senile cataract is large, and it is obviously inappropriate to exercise cataract capsulorhexis by using untreated pig eyeballs.

Therefore, there is an urgent need to develop a method that can transform the mechanical properties of the anterior capsule of an isolated porcine eye lens into those similar to those of the anterior capsule of a human eye lens to facilitate continuous annular capsulorhexis exercises by cataract surgery beginners.

Disclosure of Invention

In order to solve the problems, the main purpose of the invention is to provide a method for treating the anterior capsule of an isolated pig eyeball, which can change the mechanical characteristics of the anterior capsule of an isolated pig eye lens to be similar to those of the anterior capsule of a human eye lens, and can better simulate the experience during cataract surgery.

It is another object of the present invention to provide a capsulorhexis training model for cataract surgery.

In order to achieve the above purpose, the present invention provides a method for treating the anterior capsule of an isolated pig eyeball, comprising the following steps:

1) Diluting 1% sodium hypochlorite solution with water to obtain sodium hypochlorite solution with the mass percent concentration of 0.3%;

2) Placing the isolated pig eyeball in a pig eye fixing device with the cornea level upward;

3) Puncturing an opening with a caliber of 3.0mm at the corneoscleral edge with a 3.0mm puncture knife;

4) Cutting the cornea along the cornel limbus using a corneal scissors to expose the anterior capsule of the lens;

5) Dripping 0.3% sodium hypochlorite solution to the surface of the anterior capsule membrane by a syringe for soaking for 5 minutes;

6) The anterior capsule surface was then immediately rinsed 3 times with 0.9% physiological saline.

The invention also provides a cataract surgery capsulorhexis training model prepared by the method for processing the anterior capsule of the isolated pig eyeball.

The method for treating the in-vitro porcine eyeball pre-capsule provided by the invention can achieve the mechanical characteristics similar to those of the human eye lens pre-capsule by treating the porcine eye lens pre-capsule with sodium hypochlorite solution with proper concentration.

The invention has the beneficial effects that:

the invention provides a method for treating an isolated pig eyeball anterior capsule, which can change the toughness of the isolated pig eye lens anterior capsule so as to achieve the similar mechanical characteristics as a human eye lens. The model can simulate the experience of cataract surgery well, is beneficial to the cataract surgery beginner to carry out continuous annular capsulorhexis training, and can also be used for evaluating the capsulorhexis operation of the ophthalmic surgery robot.

Drawings

Fig. 1 is a photograph of a pig's eye fixed using a pig's eye fixing device according to the present invention.

Fig. 2 is a photograph of a stretcher used in the present invention.

Detailed Description

The embodiments of the present invention will be described in detail and fully described below to enable those skilled in the art to more readily understand the advantages and features of the present invention and to make a more clear and concise definition of the scope of the present invention.

Materials:

1. fresh pig eyeballs are purchased from Pengcheng food company, are collected from Duroc and Changbai pig binary hybrid pigs of 6 months in size, and are qualified through quarantine.

2. Human lens anterior capsule: the anterior capsule specimens reserved in the process of major operations of the equine department in Beijing-like homozygous hospitals pass through the examination of ethical committee of Beijing-like homozygous hospitals affiliated to the university of capital medical science.

Sodium hypochlorite solution at 3.1% was purchased from langerhans biological medicine (wuhan) limited.

4. Laboratory tertiary water is purchased from Shanghai ear of China environmental protection technology Co., ltd

5. Ophthalmic surgical microscopes (topcon) are used for capsulorhexis procedures, which are performed under a surgical microscope.

6. The pig eye fixing device is an eyeball simulation support MR-D300 purchased from Mingren medical instruments Inc. of Suzhou, and is used for fixing pig eyeballs.

7. The stretcher is composed of a Nano17 six-dimensional force sensor (ATI Industrial Automation, NC, USA) and a linear displacement table MTS 203 (beijing north optical century instruments limited, china).

The rest of the devices without the source noted are common devices for ophthalmic surgery.

Example 1: in vitro porcine eyeball anterior capsule treatment and capsulorhexis evaluation

Taking 20 isolated fresh pig eyeballs, checking by a slit lamp, and eliminating diseases such as iritis, lens lesions, keratopathy and the like. Before the test, the isolated pig eyeballs are placed in a refrigerator at 4 ℃ for preservation, and the test is carried out within 24 hours after the eyeballs are taken down.

1. The 1% sodium hypochlorite solution was diluted with laboratory tertiary water to 0.1%, 0.3%, 0.5%, 0.7%, 0.9% sodium hypochlorite solutions of different concentrations.

2. The isolated pig eyes were placed in a pig eye fixture with the cornea level up as shown in fig. 1.

3. A3.0 mm aperture opening was pierced in the scleral edge with a 3.0mm piercing knife.

4. Then, the cornea was cut down along the pig's corneoscleral edge using a corneal scissors.

5. Sodium hypochlorite solutions with concentration of 0.1%, 0.3%, 0.5%, 0.7% and 0.9% are grouped into 1-5 groups, and two fresh isolated pig eyeballs with corneas removed are randomly distributed in each group.

6. And (3) dripping sodium hypochlorite solution with corresponding concentration on the surface of the anterior capsule by using a syringe in each of 1-5 groups to fully infiltrate the anterior capsule, and timing for 5 minutes.

7. And then, immediately flushing the surface of the anterior capsule with a large amount of physiological saline for 3 times to obtain the treated isolated porcine eyeball anterior capsule similar to the human anterior capsule.

Capsulorhexis was performed under an ophthalmic surgical microscope by a physician skilled in cataract capsulorhexis procedure using capsulorhexis forceps, and the anterior capsule obtained from capsulorhexis was measured in thickness with a micrometer, compared with the hand feel of human cataract operation capsulorhexis, and evaluated, and the results are shown in table 1.

The capsulorhexis evaluation criteria were as follows:

stage I: the texture is tough, the capsulorhexis is obviously felt to be laborious when being torn, the capsulorhexis shape is difficult to control, and the circular shape can be formed by hard traction.

Stage II: the texture is tough, and the round shape can be formed by pulling with larger force.

III grade: the quality is moderate, the capsulorhexis is easy to control and process to be round.

Grade IV: the texture is brittle, and the capsulorhexis is easy to split outwards, the strength is not easy to control, and the capsulorhexis is not easy to form a circle.

Table 1: anterior capsule thickness and tear assessment

Numbering device	Thickness (μm)	Lens turbidity	Bag toughness rating	Hand feeling of thorn bag	Hand feeling of capsulorhexis
						1	42	Ⅰ	Ⅲ	Ⅲ	Ⅲ
2	47	Ⅰ	Ⅲ	Ⅲ	Ⅲ
						3	50	Ⅰ	Ⅲ	Ⅲ	Ⅲ
4	60	Ⅰ	Ⅲ+	Ⅲ+	Ⅲ+
						5	48	Ⅰ	Ⅳ	Ⅳ	Ⅳ

The capsule toughness rating, the thorny capsule hand feeling and the capsulorhexis hand feeling rating of 1-5 are all III grades closest to human eyes and only have slight differences, so that the capsulorhexis evaluation experiment proves that the capsulorhexis hand feeling of the pig eye front capsule after being treated by sodium hypochlorite with the concentration of 0.1-0.5% is closest to that of the capsulorhexis hand feeling in the cataract operation of the human eyes.

Example 2: in-vitro porcine eyeball anterior capsule treatment and mechanical detection

60 isolated fresh pig eyeballs are taken and checked by a slit lamp to remove diseases such as iritis, lens lesions, cornea lesions and the like. Before use, the isolated pig eyeballs are placed in a refrigerator at 4 ℃ for storage. Experiments were performed within 24 hours after removal of the eyeball.

Human lens anterior capsule specimen 15 groups were stored in physiological saline before use, stored in a refrigerator at 4 ℃ and tested within 24 hours.

1. The 1% sodium hypochlorite solution was diluted with laboratory tertiary water to 0.1%, 0.3%, 0.5% sodium hypochlorite solution.

2. The isolated pig eyes were placed in the pig eye fixture prepared in example 1 with the cornea level up.

4. The cornea would then be cut down along the pig's corneoid limbus using the corneal scissors.

5. The 60 fresh isolated pig eyeballs with the cornea removed are randomly divided into A, B, C, D groups, and 15 pig eyeballs in each group are respectively numbered 1-15. Group A is a control group, and does not perform any treatment; group B is a 0.1% sodium hypochlorite solution treatment experimental group; group C is a 0.3% sodium hypochlorite solution treatment experimental group; group D was a 0.5% sodium hypochlorite solution treatment experimental group; group E is a human anterior capsule specimen group.

6. After removing cornea from group B pig eyeball, 0.1% sodium hypochlorite solution is dripped on the surface of anterior capsule membrane by a syringe for 5 minutes, and the surface is immediately washed by a large amount of physiological saline after the time is up. A continuous annular capsulorhexis was then performed, leaving a pre-lens capsule specimen obtained from the capsulorhexis.

After the cornea was removed from the group C porcine eyeball, a solution of 0.3% sodium hypochlorite was dropped on the surface of the anterior capsule by a syringe for 5 minutes, and immediately after that, the surface was rinsed with a large amount of physiological saline. A continuous annular capsulorhexis was then performed, leaving a pre-lens capsule specimen obtained from the capsulorhexis.

After removing cornea from group D pig eyeball, 0.5% sodium hypochlorite solution is dropped on the surface of anterior capsule membrane by syringe for 5 min, and the surface is washed by a large amount of physiological saline immediately after time. A continuous annular capsulorhexis was then performed, leaving a pre-lens capsule specimen obtained from the capsulorhexis.

Five sets of anterior capsule specimens were stretched using a stretcher as shown in fig. 2, and the force required for longitudinal stretching was measured, and the experimental results are shown in table 2 below, with the experimental data remaining two decimal places.

TABLE 2 statistical results of longitudinally stretched anterior lens capsule specimens

The result is subjected to rank sum test to obtain that C, D, E group and A group have significant difference, and C, D group and E group have no significant difference. That is, the magnitude of force required to stretch the porcine eye balloon anterior capsule treated with 0.3% (group C) and 0.5% (group D) sodium hypochlorite solutions was significantly different from that of the untreated porcine eye balloon anterior capsule. The mechanical characteristics of the porcine eyeball anterior capsule treated by 0.3 percent (group C) and 0.5 percent (group D) of sodium hypochlorite solution are similar to those of the human lens anterior capsule (group E), wherein the capsule is easy to split outwards in the actual capsulorhexis process in the group D, and the capsulorhexis hand feeling of the group C is more similar to that of a human. There was no significant difference between group B and group a, and between group B and group E. Namely, the force required by the anterior capsule of the pig eyeball when the anterior capsule of the pig eyeball is stretched is not obviously different from that of the anterior capsule of the pig eyeball which is not treated by 0.1 percent (group B) sodium hypochlorite solution, and the mechanical characteristics are similar. The mechanical characteristics of the porcine anterior capsule treated with 0.1% (group B) sodium hypochlorite solution were significantly different from those of the human lens anterior capsule (group E).

This shows that the treated porcine pre-tenon capsule obtained by the in-vitro porcine pre-tenon capsule treatment method provided by the invention can be used as a training model of cataract surgery practitioners.

The foregoing examples illustrate only a few embodiments of the invention and are described in detail herein without thereby limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.

Claims

1. The method for treating the anterior capsule of the in-vitro pig eyeball is characterized by comprising the following steps of:

1) Diluting 1% sodium hypochlorite solution with water to obtain sodium hypochlorite solution with mass percent concentration of 0.3% or sodium hypochlorite solution with mass percent concentration of 0.5%;

5) Dripping a sodium hypochlorite solution with the concentration of 0.3% or a sodium hypochlorite solution with the concentration of 0.5% on the surface of the anterior capsule membrane by a syringe for 5 minutes;

2. A training model of capsulorhexis for cataract surgery prepared by the method for treating the anterior capsule of an isolated pig eyeball according to claim 1.