Artificial skull piece with modified surface for stable engraftment during cranioplasty and its manufacturing method

Abstract

The present invention creates additional gaps and curves on the surface of an artificial skull fragment made of aromatic polyketone material to deform the surface, thereby increasing the surface area in contact with the scalp and simultaneously increasing frictional force, which can suppress the formation of a pseudomembrane between the artificial skull fragment and the scalp during cranioplasty and induce proper engraftment.

Description

Technology Field

[0001] The present invention relates to a surface-modified artificial skull fragment for stable engraftment during cranioplasty and a method for manufacturing the same. Background Technology

[0002] The background technology related to the present disclosure is provided herein, and these do not necessarily constitute known technology.

[0003] Cranioplasty is a surgical procedure that restores the skull to its original shape by inserting artificial bone into the skull defect area following a craniotomy. An emergency craniotomy is performed to control malignant cerebral edema, and if the patient survives, cranioplasty is performed to restore the skull defect area.

[0004] Previously, cryopreserved autologous skulls were used, but their use has declined due to concerns regarding the risk of infection and auto-absorption. As an alternative, surgeries are now performed using materials other than bone. While bone cement was previously used, it has low strength and can result in significant cosmetic variations depending on the surgeon.

[0005] Recently, 3D printers are being used for fabrication, primarily using metal (titanium) or PEEK (Polyether Ether Ketone) materials. Once manufactured, titanium cannot be deformed during surgery. Additionally, issues such as metal allergies continue to be raised. On the other hand, PEEK has very low biocompatibility and allows for deformation, such as additional trimming as needed during surgery, enabling more efficient operation.

[0006] However, in the case of PEEK material, there is a problem in that the scalp does not engraft properly intermittently, and cerebrospinal fluid (CSF) collection occurs due to cerebrospinal fluid leakage (Fig. 1). This is believed to be caused by the fact that when PEEK is manufactured, the surface is made smooth, which hinders the engraftment of the scalp.

[0007] Treatment for this requires opening a new bone fragment and suturing the cerebrospinal fluid fistula or dural defect. However, there are cases where the dura mater is completely dissolved (Fig. 2), and there are also risks associated with general anesthesia. As an alternative, histoacryl injection (Fig. 3) can be attempted, but it is not a fundamental treatment method. The problem to be solved

[0008] In order to solve the above-mentioned problems, the present invention aims to induce more stable engraftment of the scalp by creating additional gaps and curves on the surface of an artificial skull piece made of aromatic polyketone material to deform the surface.

[0009] However, the objectives of the present invention are not limited to those mentioned above, and other unmentioned objectives will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0010] The present invention provides an artificial skull piece characterized by having a lattice structure on the outer, inner, or inner and outer center of a skull piece having a curvature similar to that of a human skull.

[0011] In addition, the above-mentioned grid structure is characterized by being formed concavely on the surface of the skull piece by cutting the surface of the skull piece to have depth.

[0012] In addition, the artificial skull piece is characterized by further comprising holes provided at the intersections of the grid structure or on the grid lines.

[0013] In addition, the artificial skull piece is characterized by being formed from a polyether ether ketone (PEEK) material.

[0014] In addition, the present invention provides a method for manufacturing an artificial skull piece, characterized by comprising: a first step of manufacturing a skull piece having a curvature similar to that of a human skull; and a second step of forming a grid structure on the outer, inner, or inner and outer center of the skull piece.

[0015] In addition, the first step is a step of manufacturing a skull piece using a polyether ether ketone (PEEK) material, characterized by manufacturing the skull piece in the shape of said skull piece using an injection molding or compression molding method using a sheet, rod, or pellet extruded after polymerization of the polyether ether ketone.

[0016] In addition, the second step is characterized by forming a lattice structure on the skull piece manufactured in the first step, wherein a lattice structure having a depth from the surface of the skull piece is formed using a cutting tool.

[0017] In addition, it is characterized by further including a third step of forming holes on the grid structure manufactured in the second step. Effects of the invention

[0018] The artificial skull fragment according to the present invention increases the surface area in contact with the scalp and simultaneously increases the frictional force, thereby inhibiting the formation of a pseudomembrane between the artificial skull fragment made of aromatic polyketone material and the scalp and inducing proper engraftment. Brief explanation of the drawing

[0019] Figures 1 to 3 show images regarding the prior art and problems. Figure 4 shows a comparison image of the shape of a conventional artificial skull and an artificial skull according to an embodiment of the present invention. FIGS. 5 to 7 show the shape of an artificial skull piece according to an embodiment of the present invention. Figure 8 shows an image of an artificial skull piece equipped with only a hole. Figure 9 shows an image of a cranioplasty procedure using an artificial skull piece according to an embodiment of the present invention. Specific details for implementing the invention

[0020] All technical and scientific terms used in this specification have the same meaning as generally understood by those skilled in the art, unless otherwise noted. Furthermore, throughout this specification and claims, unless otherwise noted, the terms "comprise," "comprising," and "comprising" mean including the mentioned items, steps, or groups of items and steps, and are not used to mean excluding any other items, steps, or groups of items or groups of steps.

[0021] Before describing the present invention in detail below, it should be understood that the terms used in this specification are intended only to describe specific embodiments and are not intended to limit the scope of the invention, which is limited solely by the appended claims.

[0022] Meanwhile, various embodiments of the present invention may be combined with any other embodiments unless explicitly stated otherwise. Any feature indicated as particularly desirable or advantageous may be combined with any other features and features indicated as desirable or advantageous. Hereinafter, embodiments of the present invention and the effects thereof will be described with reference to the accompanying drawings.

[0023] The present invention aims to induce more stable engraftment of the scalp by modifying the surface of an artificial skull fragment made of aromatic polyketone material through the creation of additional gaps and holes. By increasing the surface area in contact with the scalp and simultaneously increasing friction, the formation of a pseudomembrane between the artificial skull fragment and the scalp can be inhibited, thereby promoting proper engraftment. Through this, since the accumulation of cerebrospinal fluid beneath the bone fragment and on the dura mater is inhibited by the pseudomembrane, absorption through the scalp can also be promoted. This is expected to improve the patient's quality of life and help reduce medical costs by reducing complications that may occur after cranioplasty.

[0024] An artificial skull fragment according to the present invention is characterized in that it has a lattice structure on the outer side, inner side, or the center of the inner and outer sides of a skull fragment having a curvature similar to that of a human skull. The outer side of the skull fragment refers to the surface that comes into contact with the scalp after cranioplasty, and the inner side refers to the surface that comes into contact with the meninges. Preferably, it is desirable to have a lattice structure on the center of the outer side of the skull fragment.

[0025] The grid size of the above grid structure is 1 to 2 m. If the grid size falls outside the above range, it is judged that if it is excessively small, the risk of infection is high due to the increased possibility of bacterial attachment, and if it is excessively large, there is a problem in that the effect of increasing the surface area decreases, resulting in a negligible increase in the engraftment rate.

[0026] The above grid structure can be provided by using a separate member to machine the surface of the skull piece to form a concave shape on the surface of the skull piece, thereby having depth.

[0027] The thickness of the skull fragment is 6 mm to 10 mm, and the depth of the grid lines of the grid structure is 0.05 to 0.2 mm. If the depth of the grid lines falls outside the above range, it is judged that if it is excessively small, the possibility of bacterial attachment increases, leading to a high risk of infection; if it is excessively large, the effect of increasing the surface area decreases, resulting in a problem where the effect of increasing the engraftment rate becomes negligible. Preferably, the grid line depth / height is 0.1 mm.

[0028] The area where the above grid structure is provided is formed to be at least 50% of the area of ​​the skull piece. If the area of ​​the above grid structure is less than the above range, the effect of increasing the surface area is reduced.

[0029] The artificial skull fragment further comprises a hole provided at the intersection of the grid structure or on the grid line. By providing the additional hole, an additional location is secured where the artificial skull fragment and the dura mater can be sutured using a suture thread, thereby providing the effect of suturing closely to the center. Through this, the space for cerebrospinal fluid to accumulate is minimized, thereby preventing leakage and retention of cerebrospinal fluid.

[0030] The above-mentioned holes may be provided without limitation in shape. As an example, a circular hole is provided in FIG. 5 and a straight hole is provided in FIG. 6. Compared to the case where only holes are provided ( FIG. 8), the effect intended by the present invention can be enhanced when both holes and a grid structure are provided ( FIG. 9).

[0031] The above skull fragment is formed from polyether ether ketone (PEEK) material.

[0032] An artificial skull piece according to another embodiment of the present invention comprises: a first step of manufacturing a skull piece; and a second step of forming a lattice structure on the skull piece. Additionally, a third step of forming holes on the lattice structure after the second step may be further included.

[0033] The first step described above involves manufacturing a skull fragment having a curvature similar to that of a human skull using a polyetheretherketone material. This is achieved by using an injection molding or compression molding method to produce a skull fragment shape from a sheet, rod, or pellet extruded after polymerization of the polyetheretherketone. The size and shape of the artificial skull fragment are customized using the patient's CT images.

[0034] The second step above is a step of forming a grid structure on the outer, inner, or inner and outer center of the skull piece manufactured in the first step above, by using a cutting tool to form a grid structure with a depth of 0.05 to 0.2 mm. When using a cutting tool, the processing conditions are preferably 25,000 to 35,000 rev. / min RPM and a feed rate of 800 to 1,200 mm / min.

[0035] The third step is a step of forming a hole on the grid structure manufactured in the second step, wherein a hole penetrating the artificial skull piece is formed using a cutting tool.

[0036] The artificial skull fragment manufactured including the above steps increases the surface area in contact with the scalp and simultaneously increases frictional force, which can inhibit the formation of a pseudomembrane between the PEEK artificial skull fragment and the scalp and induce proper engraftment.

[0037] Examples

[0038] A 61-year-old female patient visited the emergency room of the Regional Trauma Center of our hospital due to a fall. The patient was in a state of reduced consciousness, unable to open her eyes or speak. An emergency head CT scan revealed acute subdural hemorrhage and acute epidural hemorrhage. Consequently, emergency craniotomy and hematoma removal were performed. Due to the presence of severe cerebral edema, the skull could not be reattached and was removed, after which the skin was sutured. Following the surgery, the patient was placed in the neurosurgery intensive care unit to attempt to lower intracranial pressure using medication. Thirty days after the surgery, the patient regained consciousness and underwent rehabilitation therapy while some cognitive, speech, and motor impairments remained. To address the intracranial pressure reduction caused by the skull defect, a patient-specific artificial bone fragment was fabricated using newly performed CT images. Surgery was performed on January 13, 2025 (Fig. 9) using an artificial skull fragment manufactured according to an embodiment of the present invention, rather than a conventional smooth surface. The patient was discharged after surgery with no cerebrospinal fluid leakage and proper engraftment of the scalp, and is currently undergoing outpatient follow-up without any particular issues.

[0039] The features, structures, effects, etc. exemplified in each of the aforementioned embodiments may be combined or modified and implemented in other embodiments by a person skilled in the art to which the embodiments belong. Therefore, details regarding such combinations and modifications should be interpreted as being included within the scope of the present invention.

[0040] [Project Information]

[0041] - Institution Name: Catholic University

[0042] - Research Support Program: 2024 Seongui Scholarship Academic Research Program

[0043] - Project Title: Development of Artificial Skull Fragments for Stable Graft Integration in Cranioplastic Surgery

[0044] - Research Project No.: 52023B000100327

[0045] - Implementing Agency: Uijeongbu St. Mary's Hospital

[0046] - Research Period: 2024-03-01 ~ 2025-02-28

Claims

Claim 1 An artificial skull piece characterized by having a lattice structure on the outer, inner, or inner and outer center of a skull piece having a curvature similar to that of a human skull. Claim 2 The artificial skull piece according to claim 1, characterized in that the lattice structure is formed concavely on the surface of the skull piece by cutting the surface of the skull piece to have depth. Claim 3 The artificial skull piece according to claim 1, characterized in that the artificial skull piece further comprises a hole provided on an intersection point or grid line of the grid structure. Claim 4 An artificial skull piece according to claim 1, characterized in that the artificial skull piece is formed from a polyether ether ketone (PEEK) material. Claim 5 A method for manufacturing an artificial skull piece, characterized by comprising: a first step of manufacturing a skull piece having a curvature similar to that of a human skull; and a second step of forming a grid structure on the outer, inner, or inner and outer center of the skull piece. Claim 6 A method for manufacturing an artificial skull fragment according to claim 5, wherein the first step is a step of manufacturing a skull fragment using a polyether ether ketone (PEEK) material, and wherein the first step is a step of manufacturing the skull fragment shape using an injection molding or compression molding method using a sheet, rod, or pellet extruded after polymerization of polyether ether ketone. Claim 7 A method for manufacturing an artificial skull piece according to claim 5, wherein the second step is a step of forming a lattice structure on the skull piece manufactured in the first step, and is characterized by forming a lattice structure having a depth from the surface of the skull piece using a cutting tool. Claim 8 A method for manufacturing an artificial skull piece, characterized by further including, in claim 5, a third step of forming a hole on the grid structure manufactured in the second step.

Images