CN216362003U

CN216362003U - Operation training model

Info

Publication number: CN216362003U
Application number: CN202121706884.4U
Authority: CN
Inventors: 吴俊中; 尹树伟
Original assignee: Zhuhai Saina Digital Medical Technology Co ltd
Current assignee: Zhuhai Saina Digital Medical Technology Co ltd
Priority date: 2021-07-26
Filing date: 2021-07-26
Publication date: 2022-04-22
Anticipated expiration: 2031-07-26

Abstract

The application relates to the technical field of medical equipment, in particular to an operation training model. The surgical training model comprises a first tissue, a second tissue and a tissue gap layer, and the tissue gap layer is arranged between the first tissue and the second tissue, so that the first tissue and the second tissue are separated by a gap, and the tissue layers are easily distinguished. And by making the tear strength of the tissue interstitial layer less than the tear strength of the first tissue and the tear strength of the tissue interstitial layer less than the tear strength of the second tissue, the tissues are easily separated from each other. The operation training model that this application embodiment provided, the tissue level is clearly distinguished easily, and separates easily between each tissue, and the simulation operation process of being convenient for has improved operation simulation's authenticity to improve the operation success rate, reduce the operation risk.

Description

Operation training model

Technical Field

The application relates to the technical field of medical equipment, in particular to an operation training model.

Background

Current methods for physician skill training in clinical surgery include the following three approaches, approach 1: performing an actual surgical procedure using a human or animal cadaver; route 2: simulating the state of a patient by using a computer virtual reality system, and then performing an operation simulation process; route 3: the young doctors conduct oral teaching and operation demonstration teaching through the superior doctors, receive theoretical knowledge and then slowly accumulate experience in the subsequent actual operation. These methods all have their own disadvantages, in route 1, human or animal carcasses were the earliest to be used for preoperative training, but the ethical issues of the society today limit their use, and animal carcasses have low structural similarity to human tissue, low training effect, and in addition, carcass maintenance and maintenance costs are expensive and training costs are high. In the approach 2, the operation training is performed under a computer virtual reality system, the reality sense is insufficient, the simulation operation process is greatly different from the clinical actual operation process, and the training effect is very limited. In the approach 3, through the demonstration of the oral administration and operation of the superior doctor, the learnt doctor does not have actual operation, and the received knowledge can only be used in the actual operation, which increases the operation risk of the patient.

In order to solve the problems, a three-dimensional printing technology is adopted in the prior art, the three-dimensional printing technology can rapidly manufacture a three-dimensional printing model consistent with a pathological change part of a patient according to medical image data of the patient, and a surgery simulation process is carried out on the three-dimensional printing model, so that a doctor can really foresee the situation which can occur in the surgery from multiple aspects before the surgery, plan an actual surgery path and simulate an actual surgery process and results, and the risk of the actual surgery is greatly reduced. However, the three-dimensional printing model in the prior art usually involves a plurality of tissues, such as epithelial tissues, muscle tissues, connective tissues, nerve tissues, etc., which are closely connected together, and in the process of surgery simulation, it is difficult to distinguish the tissue layers and separate the connected tissues, which is not beneficial to the performance of the surgery simulation process and reduces the reality of the surgery simulation.

SUMMERY OF THE UTILITY MODEL

An object of the application is to provide an operation training model, this operation training model can distinguish the tissue level and easily with the tissue separation that links to each other, the simulation operation process of being convenient for improves the authenticity of operation simulation.

In order to achieve the purpose, the following technical scheme is specifically adopted in the application:

the application provides a surgery training model, surgery training model includes first tissue, second tissue and tissue gap layer, tissue gap layer sets up first tissue with between the second tissue, the tear strength of tissue gap layer is less than the tear strength of first tissue, just the tear strength of tissue gap layer is less than the tear strength of second tissue.

In a possible embodiment, the tear strength of the tissue interstitial layer is between 0.1KN/m and 1 KN/m.

In a possible embodiment, at least a portion of the first tissue is printed from a first material, at least a portion of the second tissue is printed from a second material, at least a portion of the tissue interstitial layer is printed from a third material, the third material having a tear resistance less than the tear resistance of the first material, and the third material having a tear resistance less than the tear resistance of the second material.

In a possible embodiment, the third material is a support material.

In a possible embodiment, the tissue gap layer has a thickness of 0.1 mm to 2 mm.

In a possible embodiment, the tissue interstitial layer comprises interconnected grid cells.

In a possible embodiment, the grid cell comprises a frame part and a filling part, the tear strength of which is less than the tear strength of the frame part.

In a possible embodiment, the color of the tissue interstitial layer is different from the color of the first tissue and the color of the second tissue.

In a possible embodiment, the tissue interstitial layer is transparent.

In a possible embodiment, at least part of the first tissue and the second tissue have different colors and/or hardnesses.

In a possible embodiment, at least a portion of the first tissue is formed by printing a first material and a second material in a first ratio, at least a portion of the second tissue is formed by printing the first material and the second material in a second ratio, at least a portion of the tissue interstitial layer is formed by printing a third material having a tear resistance less than the tear resistance of the first material, and the tear resistance of the third material is less than the tear resistance of the second material.

Advantageous effects

The application provides a surgical training model, the surgical training model comprises a first tissue, a second tissue and a tissue gap layer, and the tissue gap layer is arranged between the first tissue and the second tissue, so that intervals exist between the tissues. Furthermore, the tear strength of the tissue gap layer is smaller than that of the first tissue, and the tear strength of the tissue gap layer is smaller than that of the second tissue, so that the tissues are easy to separate, the operation process is convenient to simulate, and the authenticity of the operation simulation is improved.

Drawings

FIG. 1 is a schematic structural diagram of a surgical training model provided in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a tissue space layer of a surgical training model provided in an embodiment of the present application;

fig. 3a, 3b, and 3c are schematic diagrams of grid cells of a tissue gap layer of a surgical training model according to an embodiment of the present application.

Reference numerals:

1-a first tissue;

2-a second tissue;

3-a tissue interstitial layer; 31-a frame part; 32-filling part.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

In the description of the present specification, unless explicitly stated or limited otherwise, the terms "first", "second", and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more unless specified or indicated otherwise; the terms "connected," "fixed," and the like are to be construed broadly and may, for example, be fixed or removable, integral or electrical; may be directly connected or indirectly connected through an intermediate.

The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In the description of the present application, it should be understood that the terms "upper" and "lower" used in the description of the embodiments of the present application are used in a descriptive sense only and not for purposes of limitation. In addition, in this context, it will also be understood that when an element is referred to as being "on" or "under" another element, it can be directly on "or" under "the other element or be indirectly on" or "under" the other element via an intermediate element.

The operation training model that this application embodiment provided, operation training model include first tissue 1, second tissue 2 and tissue gap layer 3, and wherein tissue gap layer 3 sets up between first tissue 1 and second tissue 2, and the tear strength of tissue gap layer 3 is less than the tear strength of first tissue 1, and the tear strength of tissue gap layer 3 is less than the tear strength of second tissue 2.

In the above scheme, the surgical training model refers to a part of the body of an organism, including systems such as the digestive system, the nervous system, the motor system, the endocrine system, the urinary system, the reproductive system, the circulatory system, the respiratory system, and the immune system; organs, such as heart, liver, lung, stomach, kidney; tissues, such as epithelial tissue, neural tissue, muscular tissue, connective tissue; cells, such as nerve cells, white blood cells, red blood cells, platelets, phagocytic cells, epithelial cells, cardiac muscle cells, stem cells. And the ambient environment in which the above structure exists, such as: the heart and its associated blood vessels, gastrointestinal tract, cardiovascular system, urinary system, respiratory tract, etc. And structures pathologically related to the above structures, such as tumor cells or tissues, wherein the organism may be human, mammal, etc.

It can be understood that before a doctor performs an operation, a large amount of practice training is often needed to improve the success rate of the operation, and at present, a corpse sample is often adopted for training, but the corpse sample is scarce in resources and high in cost, so that an operation training model needs to be manufactured for the doctor to perform operation training before the operation, the success rate of the operation is improved, and the operation risk is reduced. However, various tissues in the current operation training model are fused together and are tightly connected, so that the tissue levels are difficult to distinguish, the operation simulation process is not facilitated, and the reality of the operation simulation is reduced.

According to the surgical training model provided by the embodiment of the application, the surgical training model comprises a first tissue 1, a second tissue 2 and a tissue gap layer 3, wherein the tissue gap layer 3 is arranged between the first tissue 1 and the second tissue 2, so that a gap exists between the first tissue 1 and the second tissue 2, and the tissue levels are easily distinguished; furthermore, the tear strength of the tissue gap layer 3 is smaller than that of the first tissue 1, and the tear strength of the tissue gap layer 3 is smaller than that of the second tissue 2, so that the tissues are easy to separate, the operation process is convenient to simulate, and the authenticity of the operation simulation is improved.

Fig. 1 is a schematic view of an operation training model provided in an embodiment of the present application, and as shown in fig. 1, a first tissue 1 is a bone tissue, a second tissue 2 is a muscle tissue, and a tissue gap layer 3 is disposed between the bone tissue and the muscle tissue to separate tissue layers. Meanwhile, the tear strength of the tissue interstitial layer 3 is less than that of bone tissue, and the tear strength of the tissue interstitial layer 3 is less than that of muscle tissue, so that the muscle tissue is easily peeled from the bone tissue.

It should be noted that fig. 1 is only an example, the first tissue 1 and the second tissue 2 may be other tissues, such as skin tissue, nerve tissue, etc., and the surgical training model may further include a third tissue or even more tissues, and a tissue gap layer 3 is disposed between each tissue.

The operation training model for the doctor to perform the actual operation training can be obtained by printing the printing material, and the specific printing process can comprise the following steps:

step S10, acquiring a three-dimensional digital model of a surgical training model to be printed, wherein the surgical training model comprises a first tissue 1, a second tissue 2 and a tissue gap layer 3, the tissue gap layer 3 is arranged between the first tissue 1 and the second tissue 2, the tear resistance strength of the tissue gap layer 3 is smaller than that of the first tissue 1, and the tear resistance strength of the tissue gap layer 3 is smaller than that of the second tissue 2;

step S20, generating printing data according to the acquired three-dimensional digital model;

and step S30, performing three-dimensional printing based on the printing data and a preset printing material to obtain the operation training model.

In the practical application process, the operation training model can be integrally manufactured by three-dimensional printing, is simple and rapid, and is customized individually.

It should be noted that, in the present application, the preparation method of the surgical training model is not particularly limited, and the surgical training model may be manufactured by three-dimensional printing, or may be manufactured by other preparation methods, such as injection molding technology.

Step S10, specifically including:

acquiring medical image data of a surgical training model to be printed, wherein the surgical training model comprises a first tissue 1 and a second tissue 2;

three-dimensional modeling is performed based on the obtained medical image data, and a tissue gap layer 3 is provided between the first tissue 1 and the second tissue 2, resulting in a three-dimensional digital model of the surgical training model.

In the above printing process, in order to make the tear strength of the tissue gap layer 3 less than the tear strength of the first tissue 1 and the tear strength of the tissue gap layer 3 less than the tear strength of the second tissue 2, the tear resistance of the tissue gap layer 3 can be ensured by designing the structural characteristics of the tissue gap layer 3, such as controlling the thickness parameter of the tissue gap layer 3.

Specifically, the thickness of the tissue gap layer 3 is 0.1 mm to 2 mm, and optionally, the thickness of the tissue gap layer 3 may be specifically 0.1 mm, 0.4 mm, 0.7 mm, 1.1 mm, 1.4 mm, 1.7 mm, 2 mm, and the like, which is not limited herein. The tissue gap layer 3 has an excessive thickness, which affects the relative position between the first tissue 1 and the second tissue 2, and is difficult to tear, reducing the easy tearing property of the tissue gap layer 3. The thickness of the tissue gap layer 3 is too thin, so that the tissue layers are difficult to be distinguished, the operation simulation process is not facilitated, and the authenticity of the operation simulation is reduced.

Meanwhile, although the tear strength of the tissue gap layer 3 is smaller than the tear strength of the first tissue 1 and the tear strength of the tissue gap layer 3 is smaller than the tear strength of the second tissue 2 during the practice training of the doctor, in order to enable the separation between the tissues to be close to the separation between the real human tissues during the practice training of the doctor, the tear strength of the tissue gap layer 3 can be controlled to be 0.1KN/m to 1KN/m, so that the tissue gap layer 3 is prevented from being broken into powder or block during the tearing to be difficult to clean.

Fig. 2 is a schematic structural view of the tissue interstitial layer 3 provided in the embodiment of the present application, as shown in fig. 2, in order to facilitate separation of the first tissue 1, the second tissue 2 and the tissue interstitial layer 3 during the practice and training of a doctor, tear resistance of the tissue interstitial layer 3 may be reduced by using grid units inside the tissue interstitial layer 3, and the grid units may be other regular polyhedral structures or irregular structures.

Further, in order to make the tearability of the tissue gap layer 3 better, the tissue gap layer 3 may include a plurality of grid cells connected to each other, and the plurality of grid cells may make the structure of the tissue gap layer 3 looser, thereby making it easier to separate the respective tissues connected to the tissue gap layer 3 when performing the surgical simulation.

Specifically, the lattice unit inside the tissue gap layer 3 includes a frame portion 31 and a filling portion 32, and the tear strength of the filling portion 32 is smaller than that of the frame portion 31. Wherein, the frame part 31 of the grid unit is formed by printing solid material, and the solid material is used for ensuring that the tissue gap layer 3 has certain strength. The filler parts 32 of the lattice cells are printed out of a support material by which the tear resistance of the tissue interstitial layer 3 is reduced.

The support material includes at least one of a water-soluble support material and an alkali-soluble support material, and the solid material and the support material may be specifically selected according to actual needs, which is not limited herein.

Fig. 3a, 3b, and 3c are schematic views of grid cells provided in an embodiment of the present application, and as shown in fig. 3a, 3b, and 3c, in this embodiment, the frame portions 31 of three types of grid cells are all linear.

The shape of the frame portion 31 may be a curved shape, a spiral shape, or the like, and is not limited herein. In addition, the grid cells may have different sizes and/or shapes at different positions in the three-dimensional space of the tissue gap layer 3, and the grid cells may be distributed in a gradient, a uniform distribution, or a random distribution in the internal structure of the tissue gap layer 3. Thus, the tear strength of the tissue interstitial layer 3 can be adjusted by controlling the mesh cell size, shape and its distribution inside the tissue interstitial layer 3 according to the tear strength requirements of the tissue interstitial layer 3.

After determining the size, shape, position and distribution of the grid cells of the tissue interstitial layer 3, the preparation of the surgical training model can be started by printing the material. The printed material used to print the surgical training model may include a first material, a second material, and a third material, at least a portion of the tissue in the first tissue 1 is printed from the first material, at least a portion of the tissue in the second tissue 2 is printed from the second material, at least a portion of the tissue in the tissue gap layer 3 is printed from the third material, the third material has a tear resistance less than the tear resistance of the first material, and the third material has a tear resistance less than the tear resistance of the second material.

The first tissue 1 and the second tissue 2 may be made of a mixture of the first material and the second material. That is, at least a portion of the first tissue 1 is formed by printing the first material and the second material at a first ratio, at least a portion of the second tissue 2 is formed by printing the first material and the second material at a second ratio, and at least a portion of the tissue gap layer 3 is formed by printing the third material, wherein the tear strength of the third material is less than the tear strength of the first material, and the tear strength of the third material is less than the tear strength of the second material. The first material and the second material used in combination may have the same or different tear strengths, or the same or different colors, or the same or different shore hardnesses, or the same or different tensile strengths, etc. The first material and the second material are mixed according to a preset proportion, and the tear strength, the color or the hardness and the hardness of each area can be adjusted. That is, at least a portion of the first tissue 1 is formed by printing the first material and the second material at a first ratio, and at least a portion of the second tissue 2 is formed by printing the first material and the second material at a second ratio.

In some cases, it is desirable to form a support structure for the first tissue 1, the second tissue 2 and the tissue gap layer 3 during the printing process, the support structure being used to provide support to the surgical training model during the printing process. In particular, the support structure is printed out of the same support material as the print fill 32, and the support structure is removed after printing is complete. In the present embodiment, the filling portions 32 of the lattice cells of the tissue gap layer 3 do not need to be removed after the printing using the support material is completed. Further, the third material may be a support material, since the support material needs to have a lower tensile strength, a lower tear strength, and a lower shore hardness after curing.

In order to simulate the real feel of a human body, the first and second materials used to form the first and second tissues 1 and 2 may be soft materials. Wherein the tensile strength of the soft material is less than or equal to 5MPa, the tear strength is less than or equal to 10KN/m, and the Shore hardness after curing is less than or equal to 70A.

As an alternative solution, the first material and the second material may be soft materials with different colors. The soft material comprises, by weight, 10-75% of a soft monomer, 10-75% of a hard monomer, 5-20% of a cross-linking agent, 5-20% of a non-reactive soft resin, 0.5-10% of a photoinitiator, 0-0.5% of a coloring agent, and 0.05-8% of an auxiliary agent.

When the hardness of the first material and the second material required by the surgical training model printing material is greater than that of the soft material, the printing material further comprises a hard material, and the hard material is used in combination with the first material and/or the second material. For example, the hardness of each region is adjusted by mixing the hard material and the soft material at a predetermined ratio, wherein the mixing at the predetermined ratio means that the soft material and the hard material are printed in a specific region at a predetermined ratio to form a region having a certain hardness. The color of the hard material may be transparent, the same color as any soft material, or a color different from the soft material.

As an optional technical scheme of the application, the hard material comprises, by weight, 5-50% of vinyl oligomers, 50-95% of vinyl monomers, 0.5-10% of a photoinitiator, 0-0.5% of a colorant and 0.05-8% of an auxiliary agent.

Meanwhile, in order to make the printed operation training model more meet the requirement of an actual operation, different printing attributes can be set for different areas of the operation training model in the printing process, so that the tissue gap layer 3 and the first tissue 1 and the second tissue 2 have different printing attributes. That is, the tissue gap layer 3, the first tissue 1 and the second tissue 2 can be independently provided with printing attributes, so that the tissue gap layer 3, the first tissue 1 and the second tissue 2 have different tear strengths, especially, the tear strength of the tissue gap layer 3 is set to be smaller than that of the first tissue 1, and the tear strength of the tissue gap layer 3 is set to be smaller than that of the second tissue 2, so that the first tissue 1 and the second tissue 2 are easily separated, the simulation of the surgical process is facilitated, and the authenticity of the surgical simulation is improved.

It should be noted that the print attributes may also be set to the three-dimensional digital model in other manners. Specifically, the user may set according to actual requirements and material configuration of the printing apparatus, which is not limited in this application.

In the printing process, the tear resistance strength of different areas of the surgery training model can be obtained by printing the same material. Or the tear-resistant material can be obtained by mixing and printing a first material and a second material with different tear-resistant strengths according to a preset ratio. The mixed printing in the preset proportion means that the first material and the second material with different tear strengths are mixed and printed in the preset proportion to a specific area to form the area.

Specifically, in a specific area, a single voxel is formed by a material with different tear resistance, a plurality of voxels with different tear resistance are prepared, and the obtained plurality of voxels with different tear resistance are mixed in a preset ratio. In certain areas, the single voxel is formed by mixing a plurality of materials with different tear resistance strengths in preset proportion, and the single voxel can also be in a mixed form of other proportions. The present application does not specifically limit the specific manner of forming the tear resistance of each region, as long as the tissue gap layer 3 can be made to have different tear resistances from the first tissue 1 and the second tissue 2.

In order to facilitate the doctor to conveniently distinguish various organizations in the practice training process, the attributes set in the printing process also comprise colors. The tissue interstice layer 3 may be colored differently from the first tissue 1 and the second tissue 2 to facilitate identification of the tissue interstice layer 3 during the surgical simulation and thus to clarify the tissue levels.

In practical application, in order to make the prepared tissue space layer 3 not affect the color representation of the first tissue 1 and the second tissue 2, the third material may be a transparent material, that is, the tissue space layer 3 is transparent, and the transparent material may be a color transparent material or a colorless transparent material. Specifically, the transparent material is a material having a light transmittance of more than 10%, preferably a material having a light transmittance of more than 40%, and more preferably a material having a light transmittance of more than 80%.

As an optional technical scheme of the application, at least part of the tissue of the first tissue 1 and at least part of the tissue of the second tissue 2 can be different colors, so that a doctor can conveniently and quickly identify different tissue parts in the operation simulation process, and the accuracy of operation treatment is improved. For example, the first tissue 1 may be provided in a first color and the second tissue 2 in a second color, or a portion of the outer surface of the first tissue 1 that is inwardly thick may be provided in the first color and a portion of the outer surface of the second tissue 2 that is inwardly thick may be provided in the second color. The first color and the second color include red, white, blue, yellow, etc., which are limited herein and can be selected according to actual needs. Specifically, the color can be set according to the international anatomical common colors, for example, the muscle is dark red, the ligament, fascia, tendon, etc. are white, the artery is red, the vein is blue, the nerve is yellow, etc.

Further, the colors of the different areas can be obtained by printing materials of the same color, or by printing materials of different colors in a mixed manner at a preset ratio. The mixed printing at the preset ratio means that the area is formed by mixed printing using materials of different colors to a specific area respectively at the preset ratio.

Specifically, in a specific area, a single voxel is formed by a material with one color, and a plurality of voxels with different colors are prepared, and the voxels with different colors are mixed in a preset ratio. In addition, the color of each region may be formed by mixing a plurality of different colors of materials in a predetermined ratio in a specific region, and the specific forming manner of the color of each region is not particularly limited in the present application.

In order to make the prepared surgery training model more realistic, the properties set by the printing process also comprise hardness. Specifically, at least part of the tissue of the first tissue 1 and at least part of the tissue of the second tissue 2 have different hardness, so that the mechanical property of the human tissue is simulated really, and the authenticity of the operation simulation is improved. For example, the first tissue 1 may be set to a first stiffness and the second tissue 2 to a second stiffness, or a portion of the first tissue 1 may be set to a first stiffness and a portion of the second tissue 2 may be set to a second stiffness. For example, it may be set according to the actual stiffness of human tissue, the stiffness of muscle tissue being at least partly smaller than the stiffness of bone tissue. Of course, different portions of a single tissue may have different hardnesses, for example, the hardness of cancellous bone is less than the hardness of cortical bone.

In the three-dimensional printing process, the hardness of different areas can be obtained by printing the same material, or can be obtained by mixing and printing materials with different hardness in a preset ratio. The mixed printing at the preset ratio means that the area is formed by mixed printing using materials of different hardness to a specific area respectively at the preset ratio.

Specifically, in a specific region, a single voxel is formed of a material with one hardness, a plurality of voxels with different hardnesses are prepared, and the plurality of voxels with different hardnesses are mixed in a preset ratio, or in a specific region, a single voxel is formed of a plurality of materials with different hardnesses in a preset ratio, and the specific forming mode of the hardnesses of the regions is not particularly limited in the present application.

Claims

1. A surgical training model comprising a first tissue, a second tissue, and a tissue gapping layer disposed between the first tissue and the second tissue, the tissue gapping layer having a color different from a color of the first tissue and a color of the second tissue, the tissue gapping layer having a tear resistance less than a tear resistance of the first tissue and the tissue gapping layer having a tear resistance less than a tear resistance of the second tissue.

2. The surgical training model of claim 1, wherein the tear strength of the tissue interstitial layer is 0.1 to 1 KN/m.

3. The surgical training model of claim 1, wherein at least a portion of the first tissue is printed from a first material, at least a portion of the second tissue is printed from a second material, at least a portion of the tissue gap layer is printed from a third material, the third material has a tear resistance that is less than the tear resistance of the first material, and the third material has a tear resistance that is less than the tear resistance of the second material.

4. The surgical training model of claim 3, wherein the third material is a buttress material.

5. The surgical training model of claim 1, wherein the tissue gap layer has a thickness of 0.1 mm to 2 mm.

6. The surgical training model of claim 1, wherein the tissue gap layer comprises interconnected grid cells.

7. The surgical training model of claim 6, wherein the grid cell comprises a frame portion and a filler portion, the filler portion having a tear resistance less than a tear resistance of the frame portion.

8. The surgical training model of claim 6, wherein the tissue gap layer is transparent.

9. The surgical training model of claim 6, wherein at least a portion of the first tissue and the second tissue have different colors and/or hardnesses.