RU2815263C1 - Method of correcting craniosynostosis with insufficient thickness of skull bones - Google Patents

Abstract

FIELD: medicine; neurosurgery; maxillofacial surgery.

SUBSTANCE: invention can be used for craniosynostosis with insufficient thickness of the skull bones. In the planned area for installing titanium screws, an artificial dura mater measuring 10 by 5 mm is placed epidurally on the surface of the dura mater under the bone of the cranial vault, positioning it parallel to the bone cut, in the projection of installation of titanium screws, and moistened in saline solution is placed on top of the artificial dura mater a haemostatic sponge measuring 20 by 15 mm, so that the artificial meninges are located in the centre of the haemostatic sponge. The surface of the haemostatic sponge is dried with dry sterile gauze pads, thus fixing the artificial dura mater to the patient’s own dura mater. The titanium plate is fixed with titanium screws.

EFFECT: reduction of the number of complications in the form of postoperative liquorrhea and improvement of haemostasis in the surgical wound due to the creation of a layer of artificial dura mater and haemostatic sponge located between the dura mater of the brain and the bones of the skull, creating an additional barrier for the screw safe screwing in.

1 cl, 4 dwg, 1 ex

Description

The invention relates to the field of medicine, namely to neurosurgery and maxillofacial surgery. Advantageously, the invention can be used for surgical correction of skull disproportion using titanium plates - implants.

Studying patents for inventions and the scientific world medical literature, it becomes obvious that improving methods of surgical treatment of craniosynostosis remains relevant to this day.

Today, one of the significant problems encountered during surgical correction of craniosynostosis is the thin, sometimes lysed bones of the calvaria, which contribute to the formation of meningocele against the background of increased intracranial pressure. (Jose Hinojosa. Schmidek and Sweet Operative Neurosurgical Techniques (Sixth Edition), Chapter 65 - Methods of Cranial Vault Reconstruction for Craniosynostosis, 2012, Pages 768-790).

The disadvantage of the generally accepted method of installing titanium screws when fixing a titanium implant to the calvarium is to find the “thickest” part of the calvarial bone. This criterion is one of the key reasons in choosing the patient’s age for surgical correction of cranial deformity. If the length of the screw is not equal to the thickness of the bones of the cranial vault, where the screw is longer, after fixing the titanium plate with screws, damage to the dura mater (DRM) and possibly the brain parenchyma occurs with the sharp end of the screw. (Belchenko V.A. Craniofacial surgery: A guide for doctors. - M.: Medical Information Agency LLC, 2006. - 340 p. Belchenko V.A., Prityko A.G., Klimchuk A.V., Fillipov V.V. Craniofacial surgery in 3D format: atlas. - M.: GEOTAR-Media, 2010. - 224 p.).

Today, there are many companies that produce artificial dura maters (NeuroPatch (BBraun), Duraform (Codman), Duragen (Integra), etc.), some have a self-adhesive effect, others require mechanical stitching. Scientific experiments aimed at identifying the “best” artificial dura mater were not successful; all artificial implants had both their positive and negative sides (Alekseev D.E., Alekseev E.D., Svistov D.V. Comparative analysis of the effectiveness of defect plastic surgery dura mater during brain surgery. Journal "Problems of Neurosurgery" named after N.N. Burdenko. 2018; 82(5), pp. 48-54; RF patent for invention No. 2723738, publ. 06.17.2020 Bulletin No. 17) . The purpose of any artificial membrane is to create a reliable barrier that protects the brain from the development of cicatricial adhesions and the development of liquorrhea.

The objective of the claimed invention is to provide a safe method for implanting titanium screws when fixing titanium plates to the calvarium used in the correction of craniosynostosis.

The technical result of the claimed method is expressed in the reduction of postoperative complications, by minimizing the risks of developing damage to the dura mater of the brain, leading in the postoperative period to a serious complication - liquorrhea, as well as the development of bleeding (for example, when the parasinus venous lacuna is damaged).

The technical result is achieved by the fact that after performing bone modeling performed with an electrotrephine and movable bone flaps formed after osteotomy, before fixing them with titanium implants using titanium screws to the fixed bones of the cranial vault, in the planned area of installation of titanium screws, epidurally on the surface of the dura mater of the brain Under the fixed part of the bones of the cranial vault, first of all, an artificial dura mater measuring 10x5 mm is placed. The laid artificial dura mater is positioned with a long base parallel to the bone cut formed between the movable bone flaps and the fixed bones of the cranial vault. Then the top of the dura mater of the brain is covered with a hemostatic sponge pre-moistened in saline solution measuring 20x15 mm, covering the entire surface of the artificial meninges so that the artificial dura mater is located in the center of the laid hemostatic sponge. Next, the surface of the hemostatic sponge is dried, thereby fixing the artificial meninges to the dura mater of the brain, and then the titanium plate is fixed with titanium screws.

The advantage of the claimed method is the formation of a protective function. Before installing titanium screws in the projection of the thinned bones of the cranial vault, a created layer of artificial dura mater and hemostatic sponge, located between the dura mater of the brain and the bones of the skull, creates an additional barrier for the safe screwing in of the screw, as if increasing the thickness of the bone. The hemostatic sponge will undergo lysis over time (the time stage of self-resorption for each hemostatic sponge is determined by the manufacturer, which is specified in the instructions). During this period of time, the artificial membrane is securely fixed to the brain’s own dura mater (in the text, the word “own” dura mater of the brain is written by the authors in order to emphasize that this membrane is not artificial, but the patient’s usual dura mater). The artificial meninges are not susceptible to self-resorption and over time (for each company this time is different, which is also determined by the manufacturer) tightly fuses with the own dura mater of the brain and protects its surface. Thus, even if the screw turns out to be longer than the thickness of the bone, it will not damage the own dura mater of the brain and the tip of the screw will stop in the thickness of the artificially created barrier. And during the second stage of surgical treatment, when removing titanium implants (the second stage of surgical treatment of craniosynostosis when using titanium implants is always carried out as planned, after consolidation of osteotomy lines, consolidation of modeling zones, which is revealed during dynamic computed tomography), where titanium screws are removed does not lead to either livorrhea or bleeding from the bed of the removed screw.

The inventive method is simple, does not lengthen the time of surgical treatment, reduces the risk of developing liquorrhea in the postoperative period, and the use of a hemostatic sponge creates reliable hemostasis in this area.

The invention is illustrated by four illustrations, where photo 1 shows a computed tomography image of the cranial vault in the frontal plane before surgical treatment, in places thinned bones of the cranial vault are visualized; in photo 2 - intraoperative image, side view, on the right, bone resection was performed, bone flaps were formed, which were fixed to the cranial vault with titanium plates using titanium screws, and a protective layer consisting of an artificial dura mater and a hemostatic sponge was previously laid epidurally; in photo 3 - intraoperative image, side view, on the left, bone resection was performed, bone flaps were formed, which were fixed to the calvarium with titanium plates using titanium screws, and a protective layer consisting of an artificial dura mater and a hemostatic sponge was pre-laid epidurally; photo 4 shows a scheme for creating a protective layer, top view, where the artificial dura mater is located in the center under the hemostatic sponge, where the dimensions of the hemostatic sponge material are 20×15 mm, the dimensions of the artificial meninges are 10×5 mm, in the photograph there is one square cell measuring 5x5 mm.

The positions in the photographs indicate the following:

1 - thinned surface of the parietal bone;

2 - left side;

3 - right side;

4 - frontal side;

5 - occipital side;

6 - titanium plate fixed with titanium screws;

7 - artificial dura mater and hemostatic sponge are placed epidurally in the projection of installation of titanium screws;

8 - hemostatic sponge measuring 20×15 mm;

9 - artificial dura mater, dimensions 10×5 mm;

10 - movable bone flaps formed during osteotomy;

11 - bone cuts, allowing to divide the fixed bones of the calvarium into movable bone flaps;

12 - titanium screw fixing the titanium plate.

The method is carried out as follows.

Surgical treatment of craniosynostosis using titanium plates and titanium screws is divided into two stages, where the first stage, in order to increase the volume of the skull, corrects the deformation of the skull; the movable bone flaps formed during osteotomy are fixed with titanium plates and titanium screws to the fixed bones of the cranial vault. The essence of surgical treatment of craniosynostosis is to eliminate not only the visual deformation of the skull, but also to increase its volume, for future normal growth of the brain. The purpose of rigid fixation is to preserve the volume of the skull created during bone modeling. After some time, after consolidation of the formed bone flaps, the second stage of surgical treatment is carried out as planned - removal of titanium plates and titanium screws. The time for the child to undergo the second stage of surgical treatment is determined by dynamically performing a computed tomography scan of the brain.

The first stage of surgical treatment is carried out under endotracheal anesthesia; the position of the child on the operating table depends on the form of synostosis and does not in any way affect the new method we have developed. A skin incision is made in the area where synostosis of the bony suture of the skull occurred, then soft tissue is separated according to generally accepted criteria. After this, synostosis of the bone suture is visualized, which became the reason for the development of skull disproportion. An osteotomy is performed using an electric trephine, movable bone flaps are formed in such a way as to increase the volume of the skull. Next, the formed bone flaps are distracted away from the area of synostosis. They plan to install titanium plates, marking the place of fixation of the implants on the cranial vault with a colored, sterile marker. Before fixing movable bone flaps (after their distraction) to the fixed bones of the cranial vault with titanium implants, an artificial dura mater is first placed epidurally between the bones of the cranial vault and the brain’s own dura mater, forming a size of this shell of 10×5 mm. The artificial meninges are placed parallel to the bone cut in the projection of the planned installation of titanium screws that will fix the titanium plates. On top of the laid artificial dura mater, then, in order to fix it to the own dura mater of the brain, a hemostatic sponge soaked in physiological solution and pre-cut 20x15 mm in size is applied, so that the artificial mater is in the center, and all of it the surface was covered with a hemostatic sponge. The epidurally placed hemostatic sponge is dried with a sterile gauze pad, due to which the process of gluing the surface of the sponge and the artificial meninges to the surface of the brain's own dura mater occurs. Next, titanium implants are installed in the previously marked zone for fixing titanium plates and fixed with titanium screws. The postoperative wound is sutured in layers. An aseptic dressing is applied.

In the postoperative period, antibacterial, diuretic, and analgesic therapy is prescribed. After the postoperative wound has healed, the sutures are removed and the patient is discharged for outpatient observation at the place of residence.

The second stage of surgical treatment, “removal of titanium plates,” is carried out as planned, after consolidation of the osteotomy lines, which is determined after performing a computed tomography scan.

This stage of surgical treatment is carried out under endotracheal anesthesia, where the position of the child on the operating table also depends on the form of craniosynostosis and the surgical correction performed at the first stage. Layer-by-layer separation of soft tissues is carried out, after which titanium plates are visualized. Hemostasis is carried out. The titanium plates are removed. Next, layer-by-layer suturing of the postoperative wound is performed. An aseptic bandage is applied to the sutured wound.

The patient is observed in a hospital setting until the stitches are removed, after which he is discharged for outpatient observation at his place of residence. Computed tomography is performed 1 year after the second stage of the operation was performed in order to exclude recurrence of craniosynostosis.

Example. Patient V., 6 months old, was admitted for surgical treatment to the neurosurgical department of the Regional Children's Clinical Hospital. Diagnosis upon admission: “Craniosynostosis of the sagittal suture - scaphocephaly.”

Complaints from the child's parents regarding progressive deformation of the skull.

Upon examination, the child's condition was moderate. The patient has no neurological deficit; the child is somatically compensated.

Local status: disproportion of the frontal, parietal, occipital bones, pronounced vascular network of the scalp, which intensifies during anxiety or feeding of the child, the large fontanel is closed.

According to computed tomography, there is a deformation of the skull against the background of synostosis of the sagittal suture, pronounced “finger” impressions along the entire length of the parietal bones on both sides, cephalic index = 67% (with a norm of 75-80%), the thickness of the parietal bones of the cranial vault is sharply thinned against the background of increased intracranial pressure caused by the underlying disease - craniosynostosis.

The child underwent staged surgical treatment, where the first stage was “surgical correction of craniosynostosis using titanium plates.”

Operation protocol. Under endotracheal anesthesia, with the child lying on his stomach, a wave-shaped incision was made in the temporoparietal region, extending from the lower edge of the temporal region of one side to the lower edge of the temporal region of the opposite side. Layer-by-layer separation of soft tissues. After which synostosis of the sagittal suture is visualized. Using an electric trephine, cuts were made in the parietal bone on both sides, and movable bone flaps were formed. After distraction of the bone flaps, the dura mater of the brain was visualized. On palpation, the dura mater is tense, and rapid pulsation is observed. The bone flaps are moved to the sides, thereby increasing the volume of the skull. The planned area for installation of titanium plates and titanium screws when fixing movable bone flaps to the fixed bones of the cranial vault is marked on the cranial vault with a colored, sterile marker. Before fixing the movable bone flaps after their distraction to the fixed bones of the cranial vault with titanium implants, we first place an artificial dura mater epidurally between the bones of the cranial vault and the dura mater of the brain, and using scissors we form the required size of this fragment - 10×5 mm. We lay the artificial meninges parallel to the bone cut, in the projection of the installation of titanium screws, in order to fix the titanium plates. On top of the laid artificial dura mater, then, in order to fix it to the own dura mater of the brain, a hemostatic sponge moistened in physiological solution and pre-cut with scissors measuring 20x15 mm is applied, so that the artificial mater is in the center, and its entire surface was covered with a hemostatic sponge. The epidurally placed hemostatic sponge is dried with a sterile gauze pad, due to which the process of gluing the surface of the sponge and the artificial meninges to the surface of the brain's own dura mater occurs. Next, titanium implants are installed in the previously marked zone for fixing the titanium plates, and we fix them with titanium screws. The postoperative wound is sutured in layers. An aseptic dressing is applied.

The postoperative period proceeded without complications. The sutures from the postoperative wound were removed on the 10th day, the wound healed by primary intention, without signs of inflammation or liquorrhea. On the 10th day after the operation, the child was discharged for further observation at the place of residence. After 6 months After the first stage of surgical correction was completed, a computed tomography of the brain was performed, which visualized a satisfactorily formed configuration of the skull, elimination of the hypertensive area, consolidation between bone flaps, and an increase in the cephalic index.

The patient, 6 months after the first stage of surgical treatment of craniosynostosis, underwent “removal of titanium plates” (second stage).

Operation protocol. Under endotracheal anesthesia, with the child lying on his stomach, a wave-shaped incision was made along the old scar. Layer-by-layer separation of soft tissues. After this, titanium implants are visualized, fixed with titanium screws. Titanium plates and titanium screws were removed without technical difficulties. There are no signs of bleeding or liquorrhea. Layer-by-layer suturing of the postoperative wound was performed. An aseptic dressing is applied.

The postoperative period proceeded without complications. The sutures from the postoperative wound were removed on the 10th day, the wound healed by primary intention, without signs of inflammation or liquorrhea. On the 10th day after the operation, the child was discharged for further observation at the place of residence.

15 patients were operated on using this method in the neurosurgical department; all of them achieved satisfactory functional, therapeutic and cosmetic results; no complications were noted during the surgical treatment of this category of patients using the developed method.

The inventive method accelerates recovery and improves the quality of life of patients, reduces the risks of liquorrhea and bleeding. There were no complications during the operations, and no technical intraoperative difficulties arose.

Claims (1)

A method for correcting craniosynostosis with insufficient thickness of the skull bones, characterized by the fact that in the planned area for installing titanium screws, an artificial dura mater measuring 10 by 5 mm is placed epidurally on the surface of the dura mater under the bone of the calvarium, positioning it parallel to the bone cut, in the installation projection titanium screws, a hemostatic sponge measuring 20 by 15 mm soaked in physiological solution is placed on top of the artificial dura mater, so that the artificial meninges are located in the center of the hemostatic sponge; dry the surface of the hemostatic sponge with dry sterile gauze, thus fixing the artificial dura mater to the own dura mater; then the titanium plate is fixed with titanium screws.