RU2807900C1 - Method of surgical treatment of pterigium - Google Patents

Abstract

FIELD: medicine; ophthalmology.

SUBSTANCE: preliminary epibulbar and subconjunctative anesthesia is performed, immobilization of the pintalum head with tweezers and its cutting off the corneal surface with the help of a relaxation with the subsequent excision of the scissors to the unchanging stroma of cornea and conjunctiva with the formation of a bed for a fragment of the native amniotic membrane of the rectangular shape of the 2 mm width, according to the length of the corresponding time Measurement measures pterygium in the limbal zone. First, the previously prepared first and second components of two-component autofibrin glue are instilled into the bed for the amniotic membrane in a volume of 2–3 drops — 0.1 ml, exposed for 2 minutes, after which a fragment of the amniotic membrane is moved into the prepared bed. The first and second components of two-component autofibrin glue are re-instilled onto the placed fragment of the amniotic membrane and exposed for 2 minutes. Afterwards, the operation is completed by applying a soft contact lens to the ocular surface.

EFFECT: method allows to reduce the duration of surgery, reduce the time of epithelization, increase the comfort of patients in the postoperative period, and also reduce the risk of recurrence of pterygium.

1 cl, 1 ex, 7 dwg

Description

The invention relates to medicine, namely to ophthalmic surgery, and can be used as an effective method for the surgical treatment of pterygium.

As is known, in the southern regions of Russia the incidence of pterygium can reach up to 11% [Malozhen S.A. Pterygium: etiology, pathogenesis, treatment / Malozhen S.A. [and others]// Bulletin of Ophthalmology. - 2017. - No. 5. - P. 76-83]. In climatic areas with high levels of ultraviolet solar radiation and a dry, windy climate (a risk factor for the development of pterygium), the disease is much more common, reaching 22%. Other provoking factors for the development of this pathology include dry eye syndrome, characteristics of professional activity (increased levels of dust, working outdoors for more than 4-5 hours a day), as well as surgical interventions on the eyeball [Pavlova O.N. Methods of treatment and prevention of pterygium. / Pavlova O.N. [and others] // Bulletin of the medical institute "REAVIZ": rehabilitation, doctor and health. - 2019.- No. 3. - P. 65-73].

The triggering mechanism in the pathogenesis of pterygium is the partial death of corneal epithelial stem cells with the development of partial limbal insufficiency, which leads to the growth of fibrovascular tissue on the surface of the cornea [Zaidi, F., Bloom, P. & Corbett, M. Limbal stem cell deficiency: a clinical chameleon . Eye 17, 837-839 (2003)]. Such local scarring of the ocular surface underlies changes in the curvature and, as a consequence, the refractive properties of the cornea, which is clinically manifested in the development of high degrees of astigmatism with a decrease in visual acuity to 0.1 or lower. As it increases in size and the ingrowth of newly formed vessels, the pterygium becomes more noticeable and leads to a cosmetic defect, sharply reducing the already low visual acuity, as well as the quality of life of patients.

The only effective treatment for pterygium is its removal through various surgical methods. Currently, barrier treatment methods are used, which involve removal of the pterygium and replacement of the bulbar conjunctival defect with various tissues. However, the probability of relapse reaches 89% of cases, while up to 97% of relapses are recorded during the first year after surgery and require re-intervention [Ghiasian L. Recurrent Pterygium: A Review. / Ghiasian L. [et al.] // J Curr Ophthalmol. -2022. - No. 33(4). - P. 367-378].

Thus, today there is no effective method for surgical treatment of pterygium, and existing methods do not exclude relapse of its growth in the postoperative period. In this regard, the search for new methods of low-traumatic, simple and reliable surgical treatment of pterygium remains an urgent problem in modern ophthalmic surgery.

There is a known method of treating pterygium based on autoplasty [RF patent No. RU 2 269 988 C2 MPK, publ. 02/20/2006], which consists of using the conjunctiva of the lower outer quadrant to replace the tissue defect. The technique of the operation is as follows. Under epibulbar anesthesia, the body of the pterygium with adjacent tissue is separated and excised 2 mm from the base and 1 mm to the sides. After separating the head of the pterygium, the corneal epithelium is bluntly cleared to healthy tissue. Donor tissue is excised from the lower outer part of the conjunctival fornix 2 mm below the limbus to obtain a graft. The size of the fragment is calculated taking into account the size of the conjunctival defect plus 1 mm around the entire perimeter of the cut out area due to its reduction in the transplant area. The conjunctiva of the donor site is sutured with a continuous suture. The resulting graft is placed on the bed and fixed to the conjunctiva with a continuous 8/0 suture.

This method of surgical treatment can reduce the recurrence rate to 33% and shorten the rehabilitation period by reducing the trauma of surgical intervention [Nuzzi R, Tridico F. How to minimize pterygium recurrence rates: clinical perspectives. Clin Ophthalmol. 2018 Nov 19;2347-2362].

However, despite its advantages, the disadvantages of the proposed method are the laboriousness of the operation, which leads to an increase in the time of surgical intervention. The presence of a cosmetic defect and severe discomfort in the postoperative period due to the considerable volume of excised tissue significantly affect the level of comfort and quality of life of patients. In addition, taking an autograft in the lower fornix is limited by its size and it is not always possible to form a section of the required size. In the area where the graft is taken, there is a change in the structure of the conjunctiva and a loss of its elasticity compared to intact areas, which makes it prone to further scarring and reduces the effectiveness of the operation [Young AL, Kam KW. Pterygium: Surgical Techniques and Choices. Asia Pac J Ophthalmol (Phila). 2019 Nov-Dec;8(6):422-423].

The use of the autoconjunctival transplantation method is also limited in cases of a large area of excised tissue (with a wide, fleshy pterygium), especially in the surgical treatment of recurrent disease [Kucukerdonmez, C., Karalezli, A., Akova, Y. et al. Amniotic membrane transplantation using fibrin glue in pterygium surgery: a comparative randomized clinical trial. Eye 24, 558-566 (2010)].

These disadvantages are partially eliminated in the method of surgical treatment of pterygium with transplantation of the native amniotic membrane and its fixation with suture material [Katbaab A, Anvari Ardekani HR, Khoshniyat H, Jahadi Hosseini HR. Amniotic membrane transplantation for primary pterygium surgery. J Ophthalmic Vis Res. 2008 Jan;3(1):23-7].

This method differs from the previous one in that a fragment of the amniotic membrane corresponding to the size of the prepared bed is placed in the area of the excised pterygium on top of the exposed sclera with the basement membrane facing upward and fixed with sutures (Vicryl 8-0 or nylon 10-0) to the episclera and surrounding conjunctiva, acting as a biological “bandage” and protecting the underlying tissue. The main advantages of amnioplasty include low immunogenicity and absence of rejection reactions, significant acceleration of epithelization and restoration of the morphology of the epithelial cover, which reduces the frequency of relapses to 26.9% [Skachkov D.P. Application of biological properties of the amniotic membrane in the surgical treatment of corneal pathology / Skachkov D.P. [and others] // Far Eastern Medical Journal. - 2013. - No. 4. - P. 41-43].

However, the use of a suture method for fixing the amniotic membrane has its disadvantages, namely:

1) suturing is a labor-intensive procedure and significantly lengthens the time of surgical intervention;

2) working with materials at the microsurgical level implies high skills and skill of the surgeon;

3) the use of suture materials with a width of 0.06-0.08 mm requires caution and accuracy to avoid thread breakage;

4) the use of an amniotic membrane with a thickness of about 0.4 mm and its fixation with suture material is associated with the risk of intraoperative damage;

5) the outer ends of the threads cause irritation and increase discomfort in the postoperative period, which reduces the quality of life of patients and requires additional (corneoprotective) therapy;

6) the outer ends of the threads can injure a section of the amniotic membrane, especially during blinking movements, and lead to its dissection or rejection;

7) excessive lacrimation that occurs during irritation with threads can lead to premature lysis of the amnion due to tear enzymes when it gets under the fragment fixed with sutures;

8) suturing is associated with a high risk of postoperative infection and the formation of granulomas [Mahdy, Reda A.; Wagieh, Mostafa M. (2012). Safety and Efficacy of Fibrin Glue versus Vicryl Sutures in Recurrent Pterygium with Amniotic Membrane Grafting. Ophthalmic Research, 47(1), 23-26].

The closest to the claimed invention is the method we chose as a prototype and consists in using fibrin glue - sealant "Tisseel VH" (Baxter Healthcare Corp, Deerfield, IL) to fix a fragment of the amniotic membrane [Kucukerdonmez C. Amniotic membrane transplantation using fibrin glue in pterygium surgery: a comparative randomized clinical trial. / Kucukerdonmez C. [et al.] // Eye. - 2010. -№24(4). - P. 558-566].

The authors propose the use of two-component fibrin glue - sealant for fixing the amniotic membrane and describe the following technique for its preparation: the first component of the sealant is a concentrate of blood plasma containing human fibrinogen (70-110 g), fibronectin (2-9 mg), factor XIII (10 -50 IU), plasminogen (40-120 mcg) and bovine aprotinin solution. The second component is prepared by mixing bovine thrombin and calcium chloride solution. Before applying the components, the first component and thrombin are heated to maintain the temperature regime. Thrombin is then mixed with a calcium chloride solution to obtain the second component.

After excision of the pterygium and drying of the exposed sclera with a sponge, fibrin glue is applied to the ocular surface. To apply glue to the surface of the eye, a double injection system “Duploject” (Baxter AG, Vienna, Austria) is used, in which a solution of the first and second components from different syringes are mixed with each other directly during application due to a unifying cannula at the end of the device [Panda A , Kumar S, Kumar A, Bansal R, Bhartiya S. Fibrin glue in ophthalmology. Indian J Ophthalmol. 2009 Sep-Oct;57(5):371-9]. After applying the glue, the formed fragment of the amniotic membrane was transferred to the prepared bed, and the excess adhesive composition was removed using instruments.

The disadvantages of this method include:

1) the absence of a registered method of surgical treatment of pterygium using native amniotic membrane and fibrin glue in the Russian Federation;

2) the presence of an allogeneic (foreign) concentrate (first component) in the adhesive composition, which dictates the need for a thorough examination of the donor material for blood-contact infections;

3) an increase in the preparation time of the adhesive composition and the need to comply with production standards when obtaining the adhesive component from donor plasma;

4) the manifestation of possible allergic reactions to the protein aprotinin, which is of bovine origin and, therefore, is considered an allergen;

5) a high concentration of fibrin of the first component determines a proportionally greater intensity of conjunctival scarring processes, and, accordingly, a greater risk of developing pterygium relapse;

6) a high concentration of fibrin of the first component determines the proportionally greater intensity of corneal opacification in the postoperative period;

7) the need to maintain a certain temperature during the preparation of the adhesive composition makes the procedure more energy-consuming and difficult to implement;

8) the need to use special expensive equipment (thermal device, “Duploject” system for applying components) leads to a decrease in the level of availability of this method.

The present invention is based on the idea of creating a fast, low-traumatic, and most importantly, effective method for treating pterygium. This is achieved by using the biological properties of the native amniotic membrane, as well as the developed and patented [RF patent No. RU 2 704 256 C1 IPC, publ. 02/18/2019] two-component autofibrin glue (DAFK) as the simplest and most reliable method of tissue fixation.

The solution to this problem is ensured by the fact that in the method of surgical treatment of pterygium, which consists of preliminary epibulbar and subconjunctival anesthesia, immobilization of the head of the pterygium with tweezers and its separation from the corneal surface using a delaminator, followed by excision with scissors to the unchanged stroma of the cornea and conjunctiva with the formation of a bed for the amniotic membrane , then a rectangular section 2 mm wide is formed from the native amniotic membrane, the length corresponding to the size of the pterygium excision sector in the limbal zone, then the previously prepared first and second components of DAPC are instilled in the bed for the amniotic membrane in a volume of 2-3 drops of 0.1 ml , and their exposure for 2 minutes, after which the fragment of the amniotic membrane is moved to the prepared bed, the components of DAPC are re-instilled onto the laid fragment of the amniotic membrane and exposure for 2 minutes, after which the operation is completed by applying a soft contact lens to the eye surface.

The main advantages of our proposed method of surgical treatment of pterygium are:

1) use of a patented [RF patent No. RU 2 704 256 C1 IPC, publ. 02/18/2019] two-component autofibrin glue, providing high strength of tissue adhesion, ensuring hemostasis and stopping the inflammatory reaction at the site of application of the adhesive composition;

2) complete elimination of contamination and transfer of blood-borne infections through the use of patient blood plasma;

3) use of a minimum volume of freshly collected patient blood plasma, which speeds up the procedure for preparing the adhesive composition;

4) the absence of synthetic components in the composition of two-component autofibrin glue and the complete elimination of allergic reactions;

5) lower incidence of conjunctival scarring at the surgical site due to the use of physiological concentrations of fibrin, providing more controlled processes of tissue regeneration;

6) lower incidence of corneal opacities due to the use of physiological concentrations of fibrin and the creation of conditions for rapid regeneration;

7) ease of preparation of the adhesive composition and no need to create special temperature conditions;

8) the use of more accessible equipment (sterile tubes for obtaining platelet-rich plasma and a centrifuge), which greatly simplifies the method of preparing this adhesive composition.

The invention is illustrated in Fig. 1 and fig. 2, which shows photos of the ocular surface of the right (Fig. 1) and left (Fig. 2) eyes in dynamics. In fig. Figure 3 shows the separation of the pterygium head from the corneal surface using a delaminator. In fig. Figure 4 shows excision of the head of the pterygium with scissors to the intact stroma of the cornea and conjunctiva. In fig. Figure 5 shows the formation of a rectangular fragment of amniotic membrane 2 mm wide, the length corresponding to the size of the pterygium excision sector in the limbal zone. In fig. Figure 6 shows the exposure of DAPC components for 2 minutes. In fig. Figure 7 shows the repeated instillation of DAPC components onto a stacked AM fragment.

The effectiveness of our proposed method for treating pterygium is illustrated by the following clinical case. Patient Z. applied to the ophthalmology clinic of the V.Med. CM. Kirov with complaints of foreign body sensation, lacrimation, periodic redness of both eyes. From the anamnesis it is known that these complaints have been troubling for three years; when examined by an ophthalmologist during a medical examination at the clinic at the place of residence, an increase in the conjunctiva on the cornea on the nasal side was revealed in both eyes, and a diagnosis was made: pterygium of the second degree in both eyes. At the Ophthalmology Clinic of the V.Med. CM. Kirov underwent surgical treatment involving removal of the pterygium with plastic surgery of the amniotic membrane and fixation of the DAFC on the right eye; after 3 months, a similar volume of surgical intervention was performed on the right eye. After removal of the pterygium, the patient notes a decrease in the severity of discomfort in both eyes and has no complaints.

Among the advantages of our method of surgical treatment in this clinical example, we can note the short duration of the operation (on the right eye the duration of the intervention was 20 minutes, on the left - 14 minutes), the absence of complaints from the patient in the postoperative period (2 points on a 10-point scale, where 0 points - no discomfort, 10 points - maximum discomfort), the use of minimal conservative therapy (local antibacterial and anti-inflammatory therapy, artificial tear preparations), reducing the duration of the postoperative period to 8 days in the case of the first surgical intervention and up to 3 days in the case of surgical intervention on the fellow eye, as well as reducing the period of epithelization to 7 days in both cases, which together ensured rapid rehabilitation of the patient and made it possible to carry out further surgical interventions (removal of pterygium on the fellow (left) eye after 3 months, as well as phacoemulsification of cataracts with implantation of an intraocular lens on the right eye). During control examinations during biomicroscopy during the first 3 days after surgery, there were signs of minor postoperative inflammation (moderate superficial injection of the eyeball), which were completely relieved by the 7th day after surgery.

Photos of the ocular surface of the right (Fig. 1) and left (Fig. 2) eyes in dynamics demonstrate the presence of a conjunctival fold growing through the limbal zone onto the cornea, before surgery, the presence of a fragment of the amniotic membrane with clear boundaries in the former growth zone of the pterygium, fixed by DAFK, on the first day after surgery (marked with an arrow), no signs of inflammation and relapse of pterygium growth one year after surgery on the right eye and 9 months after surgery on the left eye.

Currently, the patient has no visual complaints, visual acuity in both eyes is 1.0, and no relapse of pterygium growth is observed. Thus, performing surgical intervention on both eyes using the proposed method in this case led to relief of discomfort and an increase in the patient’s quality of life, his rapid rehabilitation and return to normal life.

The technical result is to increase the effectiveness of surgical treatment of pterygium by reducing the duration of surgery, reducing the time of epithelization, increasing patient comfort in the postoperative period, as well as reducing the risk of recurrence of pterygium.

The technical result is achieved by the fact that the first and second components of DAPC are prepared in advance, which are collected in 2 different sterile syringes with a volume of 1 ml. After anesthesia: epibulbar - instillation of anesthetic (inocaine), subconjunctival - 0.2 ml of a 2% lidocaine solution, the head of the pterygium is immobilized with tweezers, separated from the corneal surface using a delaminator (Fig. 3), excision with scissors to the unchanged stroma of the cornea and conjunctiva (Fig. 4). Next, a rectangular fragment 2 mm wide is formed from the amniotic membrane, the length corresponding to the size of the sector of excision of the pterygium in the limbal zone (marked with an arrow, Fig. 5). The first and second components of DAPC are instilled into the prepared bed for the amniotic membrane in a volume of 2-3 drops (0.1 ml), and exposed for 2 minutes (Fig. 6), after which a fragment of the amniotic membrane is moved into the prepared bed . This is followed by repeated instillation of the DAPC components onto the laid fragment of the amniotic membrane (marked with an arrow, Fig. 7), exposure for 2 minutes. The operation is completed with the application of a soft contact lens.

This method has proven itself to be an effective and atraumatic method of surgical treatment of pterygium.

Claims (1)

A method of surgical treatment of pterygium, consisting of preliminary epibulbar and subconjunctival anesthesia, immobilization of the head of the pterygium with tweezers and its separation from the corneal surface using a delaminator, followed by excision with scissors to the unchanged stroma of the cornea and conjunctiva with the formation of a bed for a fragment of the native amniotic membrane of a rectangular shape 2 mm wide, along the length of the sector corresponding to the size of the excision of the pterygium in the limbal zone, characterized in that first the instillation of the previously prepared first and second components of two-component autofibrin glue is carried out in the bed for the amniotic membrane in a volume of 2-3 drops - 0.1 ml, their exposure for 2- x minutes, after which the fragment of the amniotic membrane is moved to the prepared bed, the first and second components of the two-component autofibrin glue are re-instilled onto the laid fragment of the amniotic membrane and exposed for 2 minutes, after which the operation is completed by applying a soft contact lens to the ocular surface.