JP2023112391A - medical sheet - Google Patents

Abstract

Kind Code: A1 A medical sheet is provided that can contribute to accurate dimensional determination of tissue during microsurgery and can retain physiological saline or the like sprayed on the sheet for a long period of time. A medical sheet (1) includes a sheet-like main body (10) and a drawing part (20) formed on the main body and having a plurality of lines. The main body has a porous water-retaining layer 15, and at least a portion of the water-retaining layer is exposed on the surface on which the image portion is located. The lines have a pitch of 500 μm or less and a line width of 100 μm or less. [Selection drawing] Fig. 2

Description

TECHNICAL FIELD The present invention relates to a medical sheet, and more particularly to a medical sheet that is placed in an operating field and used for various measurements and the like.

2. Description of the Related Art Microsurgery, in which minute tissues such as blood vessels and nerves are detached and sutured using an operating microscope, is widely performed on various organs.

Microsurgery uses a needle with a diameter of about 50 μm to 100 μm and a thread with a diameter of about 10 μm to 20 μm. Both the needle and the thread are fine, and extremely precise work is required.
Also, in suturing tissues, it is sometimes required to match the dimensions of two tissues to be sutured, and it is important to accurately grasp the dimensions of the tissues at the operating site.

As a measurement member for medical use, Patent Document 1 describes a graduated adhesive tape for medical use.

JP-A-8-56983

The graduated adhesive tape described in Patent Literature 1 is intended to record the progress of treatment by photography, and is used by being attached to the affected area. That is, it is not considered to be used for organs inside the body.
Furthermore, in microsurgery, since the scaled adhesive tape cannot be attached to the tissue to be treated, the scaled adhesive tape described in Patent Document 1 cannot be applied.

In addition, when the tissue temperature rises due to the effects of illumination during surgery, etc., protein denaturation may damage or cause necrosis of cells.
In order to prevent this, physiological saline, etc. is sprayed in the surgical field to suppress the temperature rise. The frequency of operations increases and becomes complicated. From such a point of view, it is also required that the physiological saline solution or the like sprayed on the sheet can be retained for a long time.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a medical sheet that can contribute to an accurate grasp of the size of tissue during microsurgery and that can hold physiological saline or the like sprayed on the sheet for a long period of time.

The present invention is a medical sheet comprising a sheet-like main body and a drawing portion having a plurality of lines formed on the main body.
The main body has a porous water-retaining layer, and has a structure in which at least part of the water-retaining layer is exposed on the surface on which the image portion is positioned.
The lines have a pitch of 500 μm or less and a line width of 100 μm or less.

INDUSTRIAL APPLICABILITY The medical sheet of the present invention can contribute to accurate sizing of tissues during microsurgery and can retain physiological saline solution or the like sprayed on the sheet for a long time.

1 is a plan view of a medical sheet according to one embodiment of the present invention; FIG. It is a schematic cross section of the same medical sheet. It is an enlarged drawing which shows an information part and its periphery. FIG. 4 is a schematic cross-sectional view of a medical sheet according to a modified example of the present invention;

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG.
FIG. 1 is a plan view of a medical sheet 1 according to this embodiment. The medical sheet 1 includes a sheet-like main body 10 and a drawing portion 20 formed on the main body 10 so as to be visible from the outside.

FIG. 2 shows a schematic cross-sectional view of the medical sheet 1. As shown in FIG. As shown in FIG. 2, the main body 10 includes a surface layer 11 forming the outer surface of the main body, and a water retaining layer 15 disposed within the surface layer 11. As shown in FIG. The surface layer 11 has an upper layer 12 positioned on the upper side and a lower layer 13 positioned on the lower side. 11.

Each layer of the body 10 is formed of a material free of residual solvent content. Specific examples include silicone, polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), polyester, polyvinyl chloride (PVC), polymethyl methacrylate, polyetheretherketone (PEEK), polyethersulfone (PES), polysulfone ( PSU), polyphenylsulfone (PPSU), polyacetal (POM), polyphenylsulfide (PPS), polyetherimide (PEI), polyimide (PI), polylactic acid, polyglycolic acid, polycaprolactone, polycarbonate, polyethylene, polypropylene, etc. polymers, copolymers of these polymers, metals such as titanium alloys, stainless steel, cobalt alloys and their oxides, thermosetting elastomers such as silicone rubber, urethane rubber, fluororubber, natural rubber, synthetic rubber, etc. , polystyrene-based (TPS), polyolefin-based (TPO), urethane-based (TPU), polyester-based (TPEE), and other thermoplastic elastomers. Moreover, inorganic powder may be contained in the polymer binder shown above. Inorganic powders can be silica, alumina, zinc oxide, titanium oxide. The inorganic powder content can be from 5% to 70% by weight. Inorganic pigments may also be contained.
The form of the main body 10 may be either film-like or plate-like. Furthermore, it may be either a flexible one having flexibility or a rigid one that does not substantially bend, and can be appropriately selected in consideration of the target organ, the procedure, and the like.

The upper layer 12 and the lower layer 13 forming the surface layer 11 are preferably made of the same material. When the upper layer 12 and the lower layer 13 are made of the same material, they can be easily joined by heating. If it is difficult to heat and bond the upper layer 12 and the lower layer 13, for example, a coupling agent or a material that chemically dissolves the surfaces of the upper layer 12 and the lower layer 13 is applied and then heated, or a material that melts itself to bond is applied to the upper layer. By disposing between 12 and lower layer 13 and heating, both can be joined.

The water retaining layer 15 has a porous structure and can retain water such as physiological saline sprayed on the surgical field in its pores. In a typical example, the water retaining layer 15 is a porous film made of synthetic resin. Examples of materials include polyester, polyvinyl alcohol (PVA), polyvinyl chloride (PVC), and polyethylene.

If the medical sheet 1 is transparent, it may be difficult to see the tissue placed on the medical sheet 1 . From this point of view, the main body 10 is preferably opaque, and more preferably has a visible light transmittance of 1% or less. If the living tissue in contact with the surface of the main body 10 opposite to the surface on which the imaging portion 20 is provided is not visually recognized through the main body 10, the tissue can be accurately confirmed during microsurgery.

The color of the main body 10 is preferably the complementary color of the living tissue. The complementary colors can be blue, greenish blue, blue-green, bluish green, green, yellowish green, yellowish blue to yellowish green. The colors from blue to yellowish green correspond to B, BG, G, and GY in the Munsell color chart. By setting the color of the main body 10 to a color ranging from blue to yellowish green, it becomes easier to visually recognize the living tissue. Specifically, the ranges of L*, a, and b in the L*ab color space of the main body 10 are preferably 25 or more and 80 or less, -80 or more and 0 or less, and -50 or more and 50 or less.
It is preferable that the body 10 has a spectral reflectance of 20% or less in the range from 570 nm to 800 nm in the visible light (wavelength band of about 350 nm to 800 nm). In the case of forming the main body from the above metal, the above colors can be realized by printing the entire surface with paint or the like. If the brightness of the main body 10 is low, the contrast with the living tissue will be good, which is preferable. The peak visible light reflectance of a body having such a brightness is generally less than 10%.

Although the thickness of the main body 10 is not particularly limited, it can be 15 μm or more and 2 mm or less. It can be about 0.1 mm to 1.0 mm for highly elastic materials, about 0.02 mm to 0.2 mm for low elastic materials, and about 0.01 mm to 0.1 mm for metals.

The plan view shape of the main body 10 exemplified in the present embodiment is a square with rounded corners, but the plan view shape of the main body 10 is not limited to this, and can be appropriately determined to be a triangle, a circle, or the like. A polygonal shape with rounded corners is less likely to damage tissue when placed in the surgical field, and is easier to pick up with tweezers or a manipulator. Polygons can also be convex hulls. If it is a convex hull, it is difficult to get caught in the tissue.

The image line portion 20 is formed on the main body 10 by printing. In this embodiment, the image portion 20 is provided on the upper surface of the upper layer 12 as shown in FIG. For example, when the upper layer 12 has transparency, the image portion 20 may be provided on the lower surface of the upper layer 12 (the surface on the water-retaining layer 15 side), or may be provided on the upper surface of the water-retaining layer 15 (the surface on the upper layer 12 side). may be provided.

The drawing part 20 is composed of a plurality of lines. FIG. 1 shows an example in which the image line portion 20 has a plurality of lines 20a mutually forming an orthogonal grid and a scale 20b dividing a portion of the plurality of lines at equal intervals. The arrangement of the lines in 20 is not limited to this, and can be set as appropriate according to the object to be measured and the like. For example, a ruled line shape composed only of a plurality of lines extending in parallel, a concentric circle shape, a radial shape, and the like can be exemplified.

The width of the lines in the image line portion 20 is 100 μm or less, and the distance (pitch, indicated by symbol P in FIG. 1) between lines extending in parallel and adjacent to each other is 500 μm or less. Within this range, the image line portion 20 may include two or more types of lines with different widths, or may have a plurality of areas with different pitches P. FIG. A streaked portion of such a size is difficult to see with the naked eye, but can be visually recognized favorably when viewed with a magnifying glass in microsurgery.

The drawing section 20 of the present embodiment has an information section 21 in addition to the lines 20a and scales 20b described above.
FIG. 3 shows an enlarged view of the information section 21. As shown in FIG. The information part 21 displays information about the medical sheet 1 including information about the specifications of the drawing part 20 . Therefore, the content of the information section differs depending on the aspect of the drawing section 20 . In the example shown in FIG. 4, the information part 21 consists of two character strings "P 500" and "L 25". “P 500” indicates a pitch of 500 μm, and “L 25” indicates a line width of 25 μm.

In this embodiment, the information section 21 is provided in a part of the grid as shown in FIG. 1, but the number and arrangement intervals of the information section can be appropriately set. Depending on the size of the operative field and the size of the operative field, the medical sheet may be used by cutting out a small part of the sheet. It is preferable to set intervals.
Note that the information section has an arbitrary configuration and may be omitted.

The ink for forming the image portion 20 has a coloring pigment and a binder.
As the coloring pigment, both organic pigments and inorganic pigments can be used.
Inorganic pigments include oxides, hydroxides, sulfides, selenides, and ferrocyanides of metals such as titanium, zinc, gold, silver, copper, and iron, or chromates and sulfates of these metals. , carbonates, silicates and phosphates can be used. Further examples include the above metals alone or alloys thereof, carbon, bismuth oxychloride which is a pearl pigment, titanium mica, fish scale foil, and the like. Among them, biocompatible titanium dioxide (titania), zinc oxide, talc, silica, mica, alumina, barium sulfate, calcium carbonate, magnesium carbonate, barium silicate, calcium silicate, metal soap, and silicone are preferred.
Examples of organic pigments include nitroso-based, nitro-based, azo-based, lake-based, phthalocyanine-based, condensed polycyclic materials, and other carbon compounds.

A resin can be used as the binder. The resin can be a composition, and the composition can be a mixture of oligomers and polymers. The resin can be soluble. The resin may be a curable resin. The curable resin can be an ionizing radiation curable resin, a thermosetting resin. The ionizing radiation curable resin can be an ultraviolet curable resin or an electron beam curable resin. The type of resin can be an acrylic resin, a urethane resin, an epoxy resin, a polyester resin, a thiol resin, or a mixture thereof. As the acrylic resin, a fluorine-based acrylic resin, a silicone-based acrylic resin, an epoxy acrylate resin, an acrylonitrile styrene resin, or a mixture thereof can be used. Other resins include methylstyrene resin, fluorene resin, polypropylene, PET (polyethylene terephthalate), PC (polycarbonate), PS (polystyrene), COC (cyclic olefin copolymer), COP (cycloolefin polymer), MS (methacrylic acid styrene copolymer), AS (acrylonitrile styrene copolymer), PEN (polyethylene naphthalate), PI (polyimide), phenol resin, melamine resin, epoxy resin, alkyd, and the like can be used.

In addition to the above, engineering plastics such as PBT (polybutylene terephthalate), POM (polyoxymethyl), PA (polyamide), PPS (polyphenylsulfide), and super engineering plastics can also be used as binders. be.

As the ink for forming the image portion 20, it is preferable to use water-based ink or non-water-based ink properly according to the characteristics of the surface of the main body 10. FIG. Water-based ink is preferably used when the surface of the main body 10 is hydrophilic. Non-aqueous inks are preferably used when the surface of the body 10 is hydrophobic.
Various solvents can be used to adjust the solids content and viscosity of the ink. For example, water-based ink can use water (purified water) or alcohol. For non-aqueous inks, solvents with high boiling points that do not easily evaporate at room temperature (aliphatic hydrocarbons, glycol ethers, higher alcohols, etc.) or solvents with low boiling points that easily evaporate at room temperature (MEK, ethanol, acetone, etc.) can be used alone or in combination. can be used In addition, dodecane, tetradecane, toluene, etc. can also be used.

The ink may contain organic fine particles or inorganic fine particles. Specific examples include acrylic particles, styrene particles, styrene acrylic particles and their crosslinked products, melamine-formalin condensate particles, polyurethane particles, polyester particles, silicone particles, fluorine particles, and epoxy particles. Polymers, smectite, kaolinite, talc and other clay compound particles, silica, titanium oxide, alumina, silica-alumina, zirconia, zinc oxide, barium oxide, strontium oxide and other inorganic oxide particles, calcium carbonate, barium carbonate, magnesium carbonate , barium chloride, barium sulfate, barium nitrate, barium hydroxide, aluminum hydroxide, strontium carbonate, strontium chloride, strontium sulfate, strontium nitrate, strontium hydroxide, and inorganic fine particles such as glass particles.
These particles can be used alone or in suitable combination. Further, it may be used after being subjected to surface treatment by coating, vapor deposition, or the like.

A printing method for forming the image portion 20 is not particularly limited. Examples of printing methods include offset printing, gravure printing, flexographic printing, screen printing, gravure offset printing, reverse offset printing, screen offset printing, tampo printing, and inkjet printing.
Among these, gravure offset printing and screen offset printing are particularly suitable because they can stably form narrow lines.

The ink forming the image portion 20 is preferably made of a material having biocompatibility. The biocompatibility of the medical sheet 1 is ensured by forming the image portion 20 with ink that is not made of a biocompatible material and then covering the ink portion with a transparent biocompatible coating. can also In this case, the coating may cover only the drawing area 20 or may cover the entire surface of the main body 10 .
The coating material can be any biocompatible material that can be used with the inks forming the body 10 and the image 20 . Preferred examples include silicone resins and fluorine resins.

The top layer 12 has through-holes 4 in a grid formed by the image areas 20 . Since the through-holes 4 penetrate the upper layer 12 in the thickness direction, a portion of the water-retaining layer 15 located below the upper layer 12 extends through the through-holes 4 on the upper surface of the medical sheet 1 where the image portion 20 is located. exposed to
Although FIG. 1 shows an example in which through holes 4 are provided in all grids, there may be grids without through holes. Moreover, there is no particular limitation on the planar view shape and size of the through-holes, and a plurality of small through-holes may be provided in one lattice. Furthermore, the form of the through-holes may be different for each lattice.

The operation of the medical sheet 1 configured as described above during use will be described.
The medical sheet 1 is placed in the surgical field as it is or after being cut into an appropriate size. It may be soaked in physiological saline or the like before being placed in the operating field. When the medical sheet 1 is immersed in liquid, the liquid penetrates into the main body 10 through the through holes 4 and is partially retained within the porous structure of the water retaining layer 15 .

When the organ or tissue to be treated is placed at an appropriate position on the medical sheet 1 or positioned slightly above the medical sheet 1, the dimensions of the organ or tissue can be grasped based on the drawing section 20. be able to.

Radiant heat and the like from lighting that illuminates the surgical field acts to increase the temperature of the medical sheet 1, but if the water retaining layer 15 retains physiological saline or the like, it evaporates and suppresses the temperature increase. In addition, it prevents drying and reduces damage to the tissue placed on the sheet and the tissue that the sheet comes into contact with.
Physiological saline or the like sprayed during the operation is also retained in the water retaining layer 15 in parallel to extend the duration of the above action.

If the liquid retained by the water retaining layer 15 is an isometric liquid such as a physiological saline solution or an infusion, the blood generated in the surgical field is less likely to enter the water retaining layer due to the difference in osmotic pressure between the liquid and the blood. As a result, there is an advantage that it is possible to prevent situations such as the tissue placed on the medical sheet from becoming difficult to see.

When blood diluted with physiological saline is retained in the water retaining layer 15, it may be slightly colored, but since the blood is diluted and has a low concentration, the visibility is not greatly impaired.
When the water retaining layer 15 contains a large amount of water, it is possible to prevent staining of the medical sheet 1 due to drying and sticking of blood on the medical sheet 1, and deterioration of tissue visibility associated therewith. As a result, the user can reduce the frequency of sprinkling physiological saline onto the surgical field, and the frequency of replacing medical sheets that have become unusable with new ones can be significantly reduced.

The main body according to the present embodiment realizes a structure in which the water-retaining layer is provided inside without using an adhesive or the like by joining the peripheral portions of the upper layer and the lower layer with the water-retaining layer 15 interposed therebetween. Therefore, the structure is easy to apply to medical devices with strict regulations on adhesives.

In the present embodiment, if there is a certain or more lightness difference between the image line portion 20 and the main body 10, the contrast becomes good, which is preferable. For example, when the difference in the average reflectance (%) of visible light is about 30 points, the contrast is good. Alternatively, the contrast between the image portion 20 and the main body 10 can be 0.1 or more and 2.0 or less in terms of color density difference, and preferably 0.5 or more and 1.5 or less in order to further improve the visibility.

The height of the image portion 20 (thickness of the layer formed on the main body 10) is preferably 1 μm or more and 10 μm or less for ease of visual recognition. The cross-sectional shape of the image portion 20 can be exemplified by a semicircular shape, a semielliptical shape, a triangular shape, a trapezoidal shape, a rectangular shape, a trapezoidal shape, or a rectangular shape whose upper portion is convexly curved. If the corners of the cross-sectional shape have edges, blood and washing liquid tend to remain on the image area 20 due to surface tension. It is preferable because it becomes difficult to stay. Furthermore, if the shape is semi-circular, semi-elliptical, triangular, or trapezoidal, it is difficult for blood, washing liquid, etc. to stay on the imaging area 20, and it is easy to flow from the medical sheet. It is easy to maintain the visibility of the wire portion 20 .
The height of the image line portion 20 can be easily adjusted by, for example, overlapping printing on the same portion when printing ink on the main body 10 .

The medical sheet according to the present invention will be further described using examples. The present invention is not limited at all by the specific contents of each of the following examples.

(Example)
A resin sheet having a thickness of 0.2 mm and serving as an upper layer and a lower layer was produced by cast molding using a two-liquid curing type silicone resin. A plurality of through-holes (inner diameter 0.05 mm) were formed in the upper sheet during cast molding.

A grid-like image area with a pitch of 100 μm was formed by printing on the sheet serving as the upper layer. The grid was set so that the through-holes were located within the grid. The basic line width was 20 μm, and every 5 lines was wider at 30 μm for the purpose of measurement. The ink forming the image portion is a white ink obtained by adding 40 wt % of titanium oxide as a pigment to a silicone resin.
The upper layer according to Example 1 was obtained by heat-curing the ink at 140° C. for 10 minutes after printing. When the line width of the image portion was measured, it increased by about 2% compared to before heating, but there was no change of 10% or more, and there was no problem with the dimensional accuracy as a scale.

A green porous sheet made of polyvinyl alcohol was prepared as the water-retaining layer, and arranged so as to be sandwiched between the upper layer and the lower layer. In this state, the peripheral portion in plan view was integrally joined by hot pressing over the entire circumference.
As described above, a medical sheet according to the example was produced. This medical sheet has flexibility.

When the medical sheet of Example 1 was immersed in physiological saline and observed with a binocular microscope at a magnification of 40, the contrast between the image and the main body was good, and the image was clearly visible. Ta.
When a porcine blood vessel was placed on a medical sheet and observed with a binocular microscope, dimensions such as length and diameter could be easily grasped based on the imaged area. The medical sheet was maintained in a moist state by the physiological saline supplied sequentially from the water-retaining layer, and drying of the blood vessels of the pig placed thereon was suppressed. Compared with porcine blood vessels placed on a resin film without a water-retaining layer, the drying time could be delayed by about 20 minutes without additional spraying of physiological saline.
In addition, the hardening blood adhering to the medical sheet could be removed by sprinkling physiological saline to suppress the hardening. This made it possible to maintain the visibility of the image area for a long period of time.

As described above, each embodiment of the present invention has been described in detail with reference to the drawings, but the specific configuration is not limited to this embodiment. included. Some examples of modifications are given below, but not all of them, and other modifications are possible. Two or more of these changes may be appropriately combined.

- In the above structure in which the water-retaining layer is sandwiched between the upper layer and the lower layer, the entire periphery does not necessarily have to be joined. For example, there may be an unbonded region in the peripheral edge portion in plan view to such an extent that the water retaining layer does not deviate. If there is an unbonded region, it can be expected that physiological saline or the like will be supplied to the water retaining layer also from the side of the main body.

- Through holes may be provided in the lower layer, or a mesh sheet may be used as the lower layer. By doing so, the physiological saline or the like that has been sprayed and wrapped around the lower side of the sheet can be supplied to the water retaining layer, and the duration of the dryness suppressing effect can be further extended.

• A coating may be provided even if the ink forming the lines and the information portion is biocompatible. While the medical sheet is in use, physiological saline or the like is continuously applied to prevent it from drying out, so the coating can suppress the attack of the physiological saline or the like on the lines and information areas.

- The total thickness of the medical sheet including the main body and the image portion can be, for example, 0.02 mm or more and 1.0 mm or less. By setting the thickness to 0.02 mm or more, the transportability at the time of manufacturing is maintained, and it is easy to ensure the dimensional accuracy of the image area. When it is 1.0 mm or less, it is easy to exhibit flexibility, and it is easy to use in microsurgery.

- The structure of the main body is not limited to the one described above. In a main body 10A related to a medical sheet 1A of the modified example shown in FIG. 4, an image portion 20 is formed in a core layer 16 made of a non-porous resin film, and the core layer 16 and the image portion 20 have a porous structure. It has a configuration covered with a water retaining layer 15 .
The manufacturing method of the main body 10A is substantially the same as that of the main body 10, and can be formed by heat-bonding the peripheral edges while sandwiching the core layer 16 between the porous upper and lower layers. In the heated peripheral portion, the porous structure is destroyed and water retention is lost, but in the water retention layer located above the core layer 16, good water retention is maintained, and similarly to the main body 10, no adhesive or the like is used. can be manufactured to
Since the porous upper layer has a cloudy appearance, the image area 20 covered with the water-retaining layer may be difficult to see. In this case, the thickness of the upper layer may be reduced or the image portion may be formed on the upper layer, if necessary.
In the main body 10A, it can be expected that the liquid retained on the lower side of the core layer will move to the upper side of the core layer, thereby maintaining the effect for a long time.

1, 1A medical sheet 4 through-holes 10, 10A main body 12 upper layer 13 lower layer 15 water retaining layer 20 drawing part 20a line 21 information part

Claims (5)

a sheet-like main body;
a drawing portion formed on the main body and having a plurality of lines;
with
The main body has a porous water-retaining layer, and at least part of the water-retaining layer is exposed on the surface on which the image portion is located,
The pitch of the plurality of lines is 500 μm or less,
The width of the plurality of lines is 100 μm or less,
medical sheet. The body is
an upper layer positioned above the water-retaining layer and having through holes;
a lower layer located below the water retaining layer,
The upper layer and the lower layer are joined at a peripheral edge portion of the medical sheet in a plan view,
The medical sheet according to claim 1. The image line section includes an information section that displays at least one of the line spacing and the line width.
The medical sheet according to claim 1. wherein the body is flexible;
The medical sheet according to claim 1. Further comprising a coating covering the image area,
The medical sheet according to claim 1.

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