Method of collagen membrane placement during tympanoplasty

Abstract

FIELD: otolaryngology.SUBSTANCE: intrameatal incision is made in the skin of the external auditory canal along the anterior-inferior-posterior wall, forming a flap until it rests against the fibrous ring along its entire length. The fibrous ring is lifted with a microneedle and the tympanic cavity is opened along the anterior-inferior-posterior wall, and the handle of the malleus is de-epidermized. The individual dimensions of the anterior-superior wall of the bony anulus, the posterior wall of the external auditory canal, and the defect of the eardrum are determined. A disc-shaped structure consisting of two parts connected by a bridge is cut out from a pre-printed collagen membrane using a bioprinter. The first part corresponds to the shape of the development of a truncated cone, the second part corresponds to the shape of a disk, the jumper is made between the disk and the area of the narrow base of the development of the truncated cone. The size of the jumper corresponds to the possibility of free movement of the first and second parts relative to each other. The size of the truncated cone scan corresponds to the individual dimensions of the patient. In this case, the area of the wide base of the cone corresponds to the dimensions of the anterior-superior wall of the bony anulus, and the area of the narrow base corresponds to the size of the cross-section of the posterior wall of the external auditory canal. The cut structure from the collagen membrane is placed by putting the first part of the cut structure in the form of a truncated cone on the handle of the malleus in the tympanic cavity. In this case, the placement is carried out in such a way that the wide base of the truncated cone scan covers the anterior-superior wall of the bony anulus, and the narrow base covers the posterior wall of the external auditory canal. The meatotympanic flap is returned to its original position. The second part of the excised collagen membrane structure, made in the shape of a disk, is brought out through the defect of the eardrum, above the surface of the defect and laid out on the surface of the remnants of the eardrum, overlapping them. Tamponade of the external auditory canal is performed.EFFECT: method allows to increase the effectiveness of tympanoplasty by creating a durable and shock-absorbing adequate structure taking into account the anatomical features of the anterior-superior wall of the bony anulus, the posterior wall of the external auditory canal, and the defect of the eardrum.1 cl, 3 dwg, 1 ex

Description

[0001] Field of technology to which the invention relates

[0002] The invention relates to medicine, namely otolaryngology, and can be used in performing tympanoplasty.

[0003] Chronic inflammation of the middle ear cavities (CHMC), characterized by the presence of persistent perforation of the eardrum (EM), constant or periodic purulent discharge from the ear and progressive hearing loss for more than 3 months.

[0004] According to various sources, up to 4% of the adult population of the planet suffers from CSOM, which is approximately 65-330 million people. In the Russian Federation, the prevalence of CSOM ranges from 8.4 to 39.2 per 1000 population, and in different age groups - from 15.3 to 52.0 cases [Ovchinnikov A.Yu., Khon E.M., Shcherbakov A.Yu. Innovative surgical technologies for the treatment of chronic suppurative otitis media. Bulletin of otolaryngology. 2018; 83 (6): 4-7]. The effectiveness of the intervention, according to domestic authors, is 43-98% [Garov E.V., Sidorina N.G., Zelenkova V.N., Lavrova A.S., Akmuldieva N.R. Analysis of the effectiveness of tympanoplasty in patients with chronic perforative otitis media. Bulletin of Otolaryngology. 2014;(6):8 11]. The success of surgical treatment is influenced by the location, size of the perforation, experience of the surgeon, condition of the mucous membrane of the tympanic cavity, type of graft / implant used [Hosny S. et al.Outcomes of myringoplasty in wet and dry ears / / The journal of international advanced otology. - 2014. - T. 10. - No. 3. - P. 256].

[0005] Technology Level

[0006] A prior art method for forming a neotympanic membrane during myringoplasty of extensive tympanic membrane defects is known (RU Patent 2537785, published January 10, 2015). The edges of the tympanic membrane perforation are refreshed, and a revision tympanotomy is performed. If necessary, the middle ear cavities are sanitized and ossiculoplasty is performed. Myringoplasty is performed using a graft of autologous auricular cartilage. A rounded section of autologous cartilage, 10-11 mm in diameter, is excised, preserving the perichondrium covering it on both sides. The perichondrium is removed on one side, while the other is preserved. The autologous cartilage, without separating it from the remaining perichondrium, is shaped into a horseshoe 1.5-2 mm wide. The superoinferior dimension of the formed cartilaginous portion is larger than the size of the bony ring. The mucous membrane of the inner surface of the remnants of the eardrum and the walls of the anterior bony ring are separated and displaced away from the fibrous ring. A bed for the graft is formed.The formed graft is placed in the graft bed with the perichondrium facing outward, with the convex side of the cartilaginous horseshoe facing the anterior portion of the bony ring. The medial aspect of the perichondrium is placed on the handle of the malleus and the posterior wall of the external auditory canal and covered with a meatotympanic flap, onto which strips of latex rubber are placed. The external auditory canal is tamponaded. This method ensures secure fixation of the graft in the anterior portions due to the shape and size of the cartilaginous component, preventing lateralization of the neotympanic membrane and graft retraction in the anterior portions of the tympanic ring.

[0007] A disadvantage of this method is the difficulty in fabricating cartilage of the required dimensions, configurations, and sizes for different patients due to the different shapes of the auricles. Furthermore, it is not always possible to position the prepared autogenous cartilage construct in this manner due to the individual geometry of the anterior angle in the area of ​​the bony anulus, which does not guarantee adequate trophism of the anterior portions of the eardrum. It is worth noting that perichondrium does not always adhere without signs of displacement in the first days and weeks after surgery, which is extremely important, as angiogenesis begins in the 3rd-4th week, and its development determines the healing of the plastic layers.

[0008] The above-mentioned problems can be partially solved by the implant material used. For example, the collagen membrane, due to its flexible structure, does not shift and maintains its shape, direction, and support for a long time. When swelled in a liquid medium, it maintains its precise shape and contact, preventing the formation of free spaces and communication between the tympanic cavity and the surrounding environment.

[0009] Currently, various materials are used to replace defects of the eardrum - autografts, cartilage grafts, fascial, collagen scaffolds of tissue engineering. For example, it is known to use a collagen membrane in tympanoplasty to close perforations of the eardrum (Swistushkin M et al. Collagen Matrix to Restore the Tympanic Membrane: Developing a Novel Platform to Treat Perforations. Polymers (Basel). 2024 Jan 15;16(2):248. Doi: 10.3390 / polym16020248. PMID: 38257047; PMCID: PMC10820519). The collagen membrane has a qualitative difference from autopsy materials. The ability to maintain its support function in liquid environments is crucial for the positive effect of tympanoplasty. During the first weeks, before the onset of angiogenesis, the plastic layers are implanted solely through the passive diffusion of the cellular matrix of the newly formed eardrum.The membrane's ability to support the entire structure during the first two weeks after surgery determines subsequent membrane healing and the success of tympanoplasty in the late postoperative period. The collagen membrane has an ordered fiber structure and exhibits sufficient rigidity and flexibility during placement, supporting diffusion and metabolic processes to prepare for the onset of angiogenesis. A rigid membrane can be conveniently positioned in the desired anatomical variation as a "strut" and passively fixed in the correct position. This fundamental action is impossible with cartilage due to its memory, and with fascia due to the rigidity of its relatively soft structure.

[0010] The closest analogue of the present invention is a method for graft placement during tympanoplasty (RU Patent 2758242, published October 27, 2021). The essence of the method is as follows. The fascia of the temporal muscle is harvested, cleaned, and dried. First, the autograft is shaped into an oval, then trimmed with scissors to form a figure "8," with the "8" having a larger and smaller portion corresponding to each other. The formed autograft is then positioned so that the larger portion covers the tympanic membrane defect, while the smaller portion is laid out on the anterior wall of the external auditory canal. The autograft is positioned under the meatotympanic flap, which includes the fibrous ring, and over the supporting cartilaginous autograft.

[0011] The disadvantages of this known method include the use of fascia as a graft, which has collagen fibers running in different directions, varying thickness in different areas, and increased elasticity when exposed to fluids. This leads to displacement of the inner disc of the prepared fascia and incomplete closure of the eardrum defect. Quite often, the refreshed perforation margins are poor for immediate angiogenesis, and the outer disc is insufficiently nourished for potential angiogenesis, which inevitably leads to reperforation and, consequently, repeat eardrum surgery in the foreseeable future. This design has the advantage of allowing for flexible flap placement, but it lacks the support properties that are essential for reliable healing.The double layer of petals in this design increases the risk of scarring of the ossicular chain beneath the structure, leading to recurrence of conductive hearing loss and scar tissue that limits ossicular chain mobility. In some cases, this serves as a repeated indication for revision of the middle ear ossicular system. In some cases, scarring can progress to hyalinosis, calcification, and ossification of the stapes, which is an indication for stapes replacement (stapedoplasty).

[0012] The problem solved in the present invention was to increase the effectiveness of tympanoplasty by forming a durable and shock-absorbing adequate structure taking into account the anatomical features of the anterior-superior wall of the bony anulus, the posterior wall of the external auditory canal, and the defect of the eardrum.

[0013] Disclosure of the essence of the invention

[0014] The technical result achieved is reliable fixation of the collagen membrane, due to the installation of an individually selected form of collagen membrane in the spacer, which ensures the most tight fit of the collagen membrane, eliminates the possibility of a loose fit and, as a consequence, the presence of microperforations that occur at the junction of the contacting surfaces, while the tamponed layered structure of the closure of the eardrum defect (the layered structure consists of a meatotympanic flap and a collagen membrane), allows for tight contact of the collagen membrane and all its layers with each other, thereby enhancing the passive diffusion necessary for angiogenesis in the layers of the plastic of the newly created eardrum.

[0015] The specified aspects of the technical result are achieved thanks to the following set of essential features:

[0016] perform an intrameatal incision of the skin of the external auditory canal along the anterior-inferior-posterior wall with the formation of a flap until it rests against the fibrous ring along its entire length,

[0017] The fibrous ring is lifted with a micro-needle and the tympanic cavity is opened along the anterior-inferior-posterior wall, and the handle of the malleus is de-epidermized.

[0018] determines the individual dimensions of the anterior-superior wall of the bony anulus, the posterior wall of the external auditory canal, and the defect of the eardrum,

[0019] A disc-shaped structure consisting of two parts connected by a bridge is cut out from a pre-printed collagen membrane using a bioprinter,

[0020] the first part corresponds to the shape of the development of a truncated cone,

[0021] the second part corresponds to the shape of the disk,

[0022] The jumper is made between the disk and the narrow base area of ​​the truncated cone scan,

[0023] the jumper size corresponds to the possibility of free movement of the first and second parts relative to each other,

[0024] in this case, the size of the truncated cone scan corresponds to the individual dimensions of the patient: the area of ​​the wide base of the cone corresponds to the dimensions of the anterior-superior wall of the bony anulus, and the area of ​​the narrow base corresponds to the size of the cross-section of the posterior wall of the external auditory canal,

[0025] The cut structure made of collagen membrane is placed by placing the first part of the cut structure in the form of a truncated cone sweep on the handle of the malleus in the tympanic cavity, and the placement is carried out in such a way that the area of ​​the wide base of the truncated cone sweep covers the anterior-superior wall of the bony anulus, and the area of ​​the narrow base covers the posterior wall of the external auditory canal,

[0026] Then the meatotympanic flap is returned to its original place,

[0027] The second part of the excised collagen membrane structure, made in the shape of a disk, is brought out through the defect of the eardrum over the surface of the defect and laid out on the surface of the remnants of the eardrum, overlapping them,

[0028] perform tamponade of the external auditory canal.

[0029] Brief description of drawings

[0030] Fig. 1 - Preoperative view of the eardrum. An oval-shaped defect is visible in the center of the photograph.

[0031] Fig. 2 - view of the eardrum 14 days after surgery, a competent eardrum with signs of vascularization is noted.

[0032] Fig. 3 - view of a structure cut out of a collagen membrane, consisting of two parts connected by a bridge, where the positions are indicated:

[0033] pos. 1 - part corresponding to the shape of the truncated cone development,

[0034] pos. 2 - part corresponding to the shape of the disk,

[0035] pos. 3 - jumper,

[0036] pos. 4 - the area of ​​the wide base of the truncated cone development,

[0037] pos. 5 - area of ​​the narrow base of the truncated cone development.

[0038] Implementation of the invention

[0039] A pre-printed collagen membrane is used to close the eardrum defect. The advantage of the collagen membrane is its rigidity, allowing it to be installed with a butt-to-butt stop against the anterior corner, acting as a spacer. This ensures the tightest possible fit, eliminating the possibility of looseness and, consequently, eliminating the risk of microperforations that occur at the junctions of the contacting surfaces.

[0040] Bioprinted collagen membranes are round discs, typically 1 cm in diameter. This size is optimal because it is sufficient to cover eardrum perforations of any location and size. The diameter of this membrane is determined by the variability of the perforation shape and allows the implant to be tailored to the individual complex shape of a specific patient's perforation.

[0041] The individual dimensions (of the patient) of the anterior-superior wall of the bony anulus, the posterior wall of the external auditory canal, and the defect of the eardrum are determined preoperatively or intraoperatively.

[0042] Under local anesthesia, after refreshing the perforation edges and creating a wound surface, an intrameatal skin incision is made along the anterior-inferoposterior wall of the external auditory canal, creating a flap that rests against the fibrous ring along its entire length. The fibrous ring is lifted with a microneedle, and the tympanic cavity is opened along the anterior-inferoposterior wall, de-epidermizing the handle of the malleus.

[0043] The bioprinted disc-shaped collagen membrane is individually prepared by cutting out a structure consisting of two parts connected by a bridge:

[0044] the first part corresponds to the shape of the truncated cone development (pos. 1),

[0045] the second part corresponds to the shape of the disk (pos. 2),

[0046] The jumper (pos. 3) is made between the disk and the narrow base area of ​​the truncated cone development.

[0047] The jumper size corresponds to the possibility of free movement of the first and second parts relative to each other.

[0048] The truncated cone scan size corresponds to the individual dimensions of the patient: the wide base area of ​​the cone corresponds to the dimensions of the anterior-superior wall of the bony anulus, and the narrow base area corresponds to the diameter of the posterior wall of the external auditory canal.

[0049] The resulting individual collagen membrane is placed by placing the first part of the cut structure in the form of a truncated cone reamer on the handle of the malleus in the tympanic cavity, wherein the area of ​​the wide base of the truncated cone reamer (pos. 4) covers the anterior-superior wall of the bony anulus, and the area of ​​the narrow base (pos. 5) covers the posterior wall of the external auditory canal.

[0050] Then the meatotympanic flap is returned to its original place.

[0051] The second part of the excised collagen membrane structure, made in the shape of a disk, is brought out through the defect of the eardrum and laid out on the surface of the remains of the eardrum.

[0052] A collagen membrane is placed over the defect, covering it, and then the external auditory canal is tamponaded. The tamponade layered structure (composed of a meatotympanic flap and a collagen membrane) ensures tight contact between the collagen membrane and all its layers, thereby enhancing passive diffusion, which is necessary for angiogenesis in the layers of the newly created eardrum.

[0053] The method we have developed allows us to reduce the length of hospital stay to 1 day due to less trauma to the retroauricular area due to the absence of additional incisions for collecting autologous materials, to reduce the time of surgery from 1 hour to 25 minutes, due to the presence of a ready-made printed collagen membrane, and to reduce the healing time from 1 month to 15-17 days, since the strength of the installation of the structure due to the tight location of the membrane in the bone annulus ensures the fastest engraftment of the membrane through an active process of directed growth of blood vessels along the collagen fibers of the printed membrane.

[0054] Clinical example

[0055] Patient H., 46 years old, was admitted to the L. I. Sverzhevsky Research Institute of Oncology and Orthopedics of the Moscow Health Department on April 15, 2025, for tympanoplasty of the left ear.

[0056] Audiometry reveals mixed hearing loss in the left ear with a 25-30 dB CVD across all frequencies. On April 15, 2025, type 1 tympanoplasty was performed using a collagen membrane using our technique.

[0057] Under local anesthesia, after resurfacing the perforation edges and creating a wound surface, an intrameatal skin incision was made in the external auditory canal. The fibrous ring was then elevated and the tympanic cavity was opened along the anterior-inferoposterior wall. The malleus handle was de-epidermized.

[0058] The prepared collagen membrane construct (type I collagen, membrane thickness 1 mm) was then placed into the tympanic cavity. The collagen membrane was positioned by placing the first part of the cut construct, in the shape of a truncated cone, on the handle of the malleus in the tympanic cavity. The wide base of the truncated cone (pos. 4) covered the anterior-superior wall of the bony anulus, and the narrow base (pos. 5) covered the posterior wall of the external auditory canal. The meatotympanic flap was returned to its original position. The second part of the cut collagen membrane construct, shaped like a disk, was brought out through the defect of the tympanic membrane and laid out on the surface of the remnants of the tympanic membrane.

[0059] Next, a tamponade was performed, for which ear tampons and external cotton wool were inserted into the external auditory canal.

[0060] The patient was examined on April 25, 2025 (the 10th day after surgery). Otoscopy revealed a stable, mobile eardrum with no pathological discharge. The auditory tube is patent, with signs of vascular growth from the periphery to the center visible. Hearing examination revealed: RR 5 m, SHR 4 m.

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