RU2848100C1 - Method for treating strabismus associated with retinopathy in premature infants - Google Patents

Abstract

FIELD: medicine; ophthalmology.

SUBSTANCE: invention can be used to treat strabismus associated with retinopathy of prematurity (ROP) in the scar phase of the disease. To do this, xeomin is injected into the hyperfunctional or hyperfunctional eye muscles. The dose of the drug is determined taking into account the initial angle of strabismus and the type of hyperfunctional eye muscle. Two units of the drug are injected into the internal rectus muscle at a convergence angle of +7+10 degrees, three units at a convergence angle of +12+15 degrees, four units at a convergence angle of +20+30 degrees , and five units at a convergence angle of +31+45 degrees. into the inferior rectus muscle and superior rectus muscle at a vertical deviation angle of 5-7 degrees - 3 units of the drug, at a vertical deviation angle of 8-10 degrees - 4 units of the drug, and at a vertical deviation angle of 11-20 degrees - 5 units of the drug; into the inferior oblique muscle - 4 units of the drug. The drug is administered into the medial rectus muscle, inferior rectus muscle and superior rectus muscle as follows: first, insert the needle into the muscle to a depth of 1 mm, 9 mm from the limbus, then move the needle along the muscle 8 mm and 1 mm deep towards the top of the orbit and inject the drug. The drug is injected into the inferior oblique muscle after it has been removed together with the Tenon's capsule through an incision in the conjunctiva at the lower outer corner of the eye, first inserting the needle into the muscle to a depth of 2 mm at the border between its outer and middle thirds, then passing the needle along the muscle for 8 mm and to a depth of 2 mm towards the lower-inner orbital rim and injecting the drug. In a specific case, the drug is administered transconjunctivally into the internal rectus muscle, the inferior rectus muscle and the superior rectus muscle using fixation eye forceps to fix the muscle. In a specific case, the drug is administered into the inferior oblique eye muscle after its removal through a 3 mm incision in the conjunctiva parallel to the limbus.

EFFECT: preservation and improvement of visual functions by eliminating the phenomena of disbinocular amblyopia, creating conditions for the development of fusion and binocular functions of the organ of vision, reducing cosmetic defects and, as a result, positively influencing the physical and mental development of the child, as well as reducing the number of complications such as the risk of trauma to surrounding tissues, perforation of the eyeball, scarring of the conjunctiva and Tenon's capsule, ischaemia of the anterior segment of the eye, transient ptosis of the upper eyelid, and reduced tear production.

3 cl, 2 ex

Description

The invention relates to medicine, namely to ophthalmology, and is intended for the treatment of strabismus associated with retinopathy of prematurity (ROP) in the cicatricial phase of the disease.

ROP is currently one of the leading causes of blindness and low vision in childhood, varying from 16% to 40% in different countries and regions. The increase in preterm births and advances in modern perinatology have led to a significant increase in the survival rate of extremely premature and immature infants and, consequently, an increased risk of developing ROP. Disability due to blindness as a result of ROP occurs in 60 people per 10 million in developed countries and 450 per 10 million in developing countries (Saidasheva E.I., Improving Ophthalmological Care for Newborns in a Megacity, Abstract of Dissertation for a Doctor of Medical Sciences, 2010).

Children with early gestational age and extremely low birth weight are a high-risk group for developing severe forms of ROP and have structural and a number of functional developmental features not only of the retina, but also of the visual analyzer as a whole. In this case, the determining factors in the formation and development of vision in ROP are not only the residual changes in the fundus after ROP (the degree of ROP), which depend on the characteristics of the course of the active phase of ROP, the timeliness and adequacy of the treatment, but also the degree of prematurity of the child at the time of birth, which directly correlates with the general immaturity of the body, as well as acute ischemic changes in the brain, leading to structural organic consequences in the future (Katarhina L.A. Pathogenesis of visual impairment in children with ROP // Visual functions and their correction in children: a guide for doctors edited by S.E. Avetisov, T.P. Kashchenko, A.M. Shamshinova. - Moscow: Meditsina, 2005. - P. 459-475).

The cicatricial phase of ROP is characterized by an unstable condition and the possibility of developing late complications and associated changes in the visual organ, the development of which leads to a decrease in visual functions and cosmetic defects, one of which is the development of strabismus.

Thus, in children with spontaneous regression of ROP, the incidence of strabismus decreases with age from 28.3% at 12 months to 19.6% over 7 years of age, and in patients with ROP after retinal coagulation, there is a tendency for the incidence of strabismus to increase from 38.7% at 12 months to 47.6% at the age of over 7 years. In patients in the cicatricial phase of ROP, three main types of strabismus are distinguished: with a predominance of the paralytic component (paralytic strabismus), concomitant (accommodative, partially accommodative) and pseudostrabismus (secondary, caused by traction ectopia of the macular due to ROP) (Kogoleva L.V. System of prevention and prognosis of visual impairment in retinopathy of prematurity, author's abstract of dis. for a Ph.D. in Medicine, 2016).

Correction of strabismus in childhood is particularly relevant due to the development of binocular functions and the development of the visual organ; therefore, creating the necessary conditions for the adequate formation of binocular vision is a priority.

As is known, for paralytic, non-accommodative, partially accommodative, and secondary types of strabismus, which are prevalent in children in the cicatricial phase of ROP, surgical treatment is the primary method of correction. The goal of the surgery is to restore symmetrical or near-symmetrical eye alignment by altering muscle balance—strengthening weak muscles or weakening strong ones. Modern tactics of strabismus surgery are characterized by the rejection of forced interventions, uniform distribution of the effect of the operation on several muscles and the use of such types of operations in which the muscle does not lose connection with the eyeball (Aznauryan I.E., Shpak A.A., Balasanyan V.O., Kudryashova E.A. Low-traumatic surgery of strabismus // Russian Children's Ophthalmology No. 4, 2019. - pp. 61-65. https://doi.org/10.25276/2307-6658-2019-4-61-65).

Muscle weakening surgeries include: recession (moving the muscle attachment site posterior to the anatomical attachment), tenotomy (cutting the muscle tendon), partial myotomy (making transverse marginal incisions on both sides of the muscle), and muscle lengthening through various plastic manipulations.

Muscle enhancing surgeries include resection of a 4-8 mm long muscle segment (depending on the intervention dosage and the angle of strabismus), formation of a muscle fold or muscle tendon fold (tenorrhaphy), and anterior muscle attachment grafting (anteriorization). In convergent strabismus, the internal rectus muscle is weakened and the external rectus muscle is strengthened; in divergent strabismus, the opposite actions are performed. Traditionally, surgical treatment methods are mostly resorted to when patients reach three years of age, taking into account previous optical correction and hardware treatment (Clinical guidelines Concomitant strabismus ICD 10: H50.0, H50.1, H50.2 Age category: children ID: KR110 Year of approval: 2017 Professional associations: All-Russian public organization "Association of Ophthalmologists").

However, the above-mentioned types of surgical treatment for strabismus are associated with high invasiveness and prolonged anesthesia, which can have negative consequences for the body and is particularly undesirable in premature patients with underlying general pathology. Therefore, chemodenervation of the extraocular eye muscles by injecting botulinum toxin type A (BTA) may be the preferred treatment for strabismus in this patient population.

Chemodenervation was introduced by Dr. Alan Scott over 30 years ago for the treatment of strabismus and is based on the mechanism of blocking acetylcholine exchange between the neurosynaptic terminals of muscle fibers. Chemodenervation with BTA can be used in situations where traditional strabismus surgery is undesirable, if the general condition is unstable, or if there are concomitant pathologies of the central nervous system, lungs, cardiovascular system, and other organs that limit the patient's stay under anesthesia. The most common complications are ptosis and conjunctival hyperemia, which resolve spontaneously within 2-3 weeks. Serious vision-threatening complications are rare. Repeated use of BTA is safe.

Compared with traditional extraocular muscle surgery such as muscle recession, the potential advantages of BTA injection for strabismus include: preservation of the anatomical features of the muscles and extraocular soft tissue blocks, reduced risk of scarring, shorter duration of anesthesia, possibly without the need for intubation, reduced risk of anterior segment ischemia due to preservation of the anterior ciliary arteries and reduced operating time, very low risk of eyeball perforation, and allows for the correction of strabismus at an earlier age - in patients under 3 years of age (Kowal L., Wong E., Yahalom C. Botulinum toxin in the treatment of strabismus. A review of its use and effects // Disabil Rehabil. 2007 Dec 15;29(23): 1823-31. doi: 10.1080/09638280701568189). All of the above advantages are of particular relevance in patients with strabismus associated with ROP in the cicatricial phase of the disease.

A surgical treatment for strabismus involves incising the conjunctiva and Tenon's bursa and isolating the extraocular muscle tendon. The tendon is divided into three parts by longitudinal incisions. A spatula is then inserted through the tendon incisions to dissect the muscle into three longitudinal bundles. The median bundle is then dissected from the sclera, thereby reducing muscle rigidity and increasing ocular motility (SU 1630820 A1).

The disadvantages of this method are the technical difficulties that arise during the isolation and manipulation of the medial portion of the tendon and muscle, in conditions of the small size of the child's orbit, with pronounced muscle rigidity in combination with a large angle of strabismus, as well as the overall wide scope of surgical intervention and its traumatic nature, which does not correspond to modern trends in reducing the invasiveness of interventions and the time of general anesthesia in pediatric practice.

A known method for treating primary hyperfunction of the inferior oblique muscle using BTA is aimed at restoring the muscle's oculomotor function. This method involves opening the conjunctival cavity and exposing the inferior oblique muscle. Tenon's capsule is incised through the conjunctival approach, the incision is extended towards the inferior and lateral rectus muscles, and the total incision length is 1 cm. Tenon's sheath is exposed and brought upward and outward in the projection of the incision. Botox is injected into the exposed inferior oblique muscle at a depth of 1.5-3 mm with 3-5 U of Botox followed by interrupted sutures on the conjunctiva (RU 2702601 C1). A disadvantage of this method is the wide conjunctival incision, which provokes excessive scarring of the periocular tissues and its limited application profile, namely, on the inferior oblique muscle.

A method for treating strabismus is known, which includes the treatment of paralytic strabismus, by administering a BTA-based drug - Dysport (IPSEN BIOPHARM, UK), which is injected into the ipsilateral extraocular muscle - antagonist of the paralyzed extraocular muscle. The BTA-containing drug used is Dysport in a dose of 10-20 Units, which is administered into the middle part of the muscular bag, at least 5 mm from the site of its attachment to the sclera, while additionally injecting the drug into one or more muscles that are contralateral synergists of the paralyzed muscles, with 10% less drug injected into the muscles that are ipsilateral antagonists than into the muscles - contralateral synergists. The method provides stimulation of afferent nerve impulses of the paralyzed muscle, which prevents its hypotrophy (RU 2257914 C1).

However, the disadvantages of this method include prolonged intervention stages due to the need to incise the conjunctiva and perform injections not only into the hyperfunctional muscle but also into the contralateral synergist muscle. This is a limiting factor in pediatric patients, especially premature infants with concomitant pathologies of the central nervous system, lungs, cardiovascular system, and other organs. It also carries a higher risk of trauma to surrounding tissues and scarring of the conjunctiva and Tenon's membrane due to the wide conjunctival incision, up to 8 mm long. This analogous method is recommended only for the treatment of paretic types of strabismus, not other types common in patients with retinopathy of prematurity.

In addition, the described method uses the pharmacological drug Dysport as a BTA, which has a high level of toxin diffusion from the injection point (the diameter of the impact field is up to 25 mm), which increases the risk of complications in the form of transient ptosis of the upper eyelid, effects on other extraocular muscles, and decreased tear production due to dysfunction of the lacrimal gland and conjunctival glands that produce tear film components.

A significant degree of changes in strabismus in children in the cicatricial phase of ROP is associated not only with the functional and structural immaturity of the neuromuscular system related to the early stages of gestation at birth, but also with concomitant neurological disorders in the form of muscle dystonia and other consequences of periventricular leukomalacia, disorganizing the coordinated regulation of the extraocular muscles (E.F. Yusupova, D.D. Gainetdinova. Periventricular leukomalacia: etiology, pathogenesis, clinical presentation, outcomes // Issues of modern pediatrics. 2010, Vol. 9, No. 4 - pp. 68-72). The presence of muscle dystonia in children with ROP does not allow us to unambiguously expect a similar effect of therapeutic procedures associated with the administration of BTA-based drugs for strabismus. Taking into account the above, in children in the cicatricial phase of ROP, correction of strabismus is traditionally performed using surgical procedures.

It is known that the thickness of muscles in the proximal and distal regions is statistically significantly smaller in premature infants, moreover, with age, the increase in skeletal muscle mass in premature infants is lower than in full-term children (G. Bertini, S. Elia, C. Dani. Using ultrasound to examine muscle mass in preterm infants at term-equivalent age // Eur J Pediatr. 2021 Feb; 180 (2): 461-468. doi: 10.1007/s00431-020-03846-7). This circumstance allows us to conclude that there is a high probability of a possible hypereffect when using traditional administration methods and dosages in children in the cicatricial phase of ROP in the treatment of strabismus, as well as a high risk of developing local complications described above due to uncontrolled diffusion of BTA.

Our goal is to develop a universal, yet individualized method for treating strabismus in children with retinopathy of prematurity in the cicatricial phase of the disease.

The technical result is the preservation and enhancement of visual functions in the long term by eliminating the phenomena of disbinocular amblyopia, creating conditions for the development of fusion and binocular functions of the visual organ, reducing the cosmetic defect, having a positive effect on the physical and mental development of the child, as well as reducing the number of complications, such as the risk of injury to surrounding tissues, perforation of the eyeball, scarring of the conjunctiva and Tenon's membrane of the eye, ischemia of the anterior segment of the eye, transient ptosis of the upper eyelid, and decreased tear production.

The proposed method is technically simple and eliminates the need for patients to remain under anesthesia for a long time.

We have been the first to select an original drug for the treatment of strabismus in children with ROP in the cicatricial phase of the disease and have established a regimen for its administration, simultaneously taking into account the anatomical features of the hyperfunctional muscle (topography, muscle thickness in ROP), the severity of strabismus, and the radius of action of the proposed drug, allowing for a personalized approach to each patient, taking into account the clinical manifestations of strabismus and the anatomical and functional features of the muscles that determine it.

For the first time, a universal treatment method for strabismus in this category of patients (children in the cicatricial phase of ROP) has been found using a BTA-based drug, who are at risk of developing complications both from the visual analyzer and from concomitant diseases of the internal organs, as well as to correct strabismus at an earlier age (in patients under three years of age).

It allows for the reduction of trauma to epibulbar tissues during the treatment of strabismus associated with retinopathy of prematurity, due to the original technique of drug administration, as well as the use of Xeomin (MERZ PHARMA, Germany), which has a more localized effect due to the low degree of toxin diffusion from the injection point (the diameter of the impact field is up to 10 mm), which allows for the achievement of a full functional result, while eliminating the risk of complications.

The essence of the invention is as follows.

For the treatment of strabismus associated with ROP in the cicatricial phase in children, xeomin (hereinafter referred to as the drug) is injected into the hyperfunctional or hyperfunctional extraocular muscles, and the dose of its administration is determined taking into account the initial angle of strabismus and the type of hyperfunctional extraocular muscle.

At the same time, they introduce

into the internal rectus oculomotor muscle at a convergence angle of +7+10 degrees - 2 U of the drug, at a convergence angle of +12+15 degrees - 3 U of the drug, at a convergence angle of +20+30 degrees - 4 U of the drug, and at a convergence angle of +31+45 degrees - 5 U of the drug;

into the inferior rectus oculomotor muscle and the superior rectus oculomotor muscle at a vertical deviation angle of 5-7 degrees - 3 U of the drug, at a vertical deviation angle of 8-10 degrees - 4 U of the drug, and at a vertical deviation angle of 11-20 degrees - 5 U of the drug;

into the inferior oblique extraocular muscle - 4 U of the drug.

Moreover, the drug is injected into the internal rectus oculomotor muscle, the inferior rectus oculomotor muscle and the superior rectus oculomotor muscle as follows: first, the needle is injected into the muscle to a depth of 1 mm, 9 mm away from the limbus, then the needle is advanced along the muscle by 8 mm and to a depth of 1 mm towards the apex of the orbit and the drug is injected.

The drug is injected into the inferior oblique extraocular muscle after its removal together with Tenon's membrane through an incision in the conjunctiva at the inferior-outer corner of the eye. First, a needle is inserted into the muscle to a depth of 2 mm at the border between its outer and middle thirds, then the needle is advanced along the muscle by 8 mm and to a depth of 2 mm in the direction of the inferior-inner orbital margin and the drug is injected.

In a particular case, the drug is injected into the internal rectus oculomotor muscle, the inferior rectus oculomotor muscle, and the superior rectus oculomotor muscle transconjunctivally, using fixation eye tweezers to fix the muscle.

In a particular case, the drug is administered into the inferior oblique extraocular muscle after its removal through a 3 mm long incision in the conjunctiva parallel to the limbus.

The proposed method is carried out as follows.

Surgical treatment is performed in an operating room with specialized anesthesia equipment for children. Patients are given an injection of Xeomin under mask anesthesia using sevoflurane for no more than 10 minutes into the hyperfunctional extraocular muscle(s)—the internal, superior, and inferior rectus muscles, as well as the inferior oblique muscle.

For injection into the internal, superior, and inferior rectus extraocular muscles, a transconjunctival grasp of the muscle tendon with the conjunctiva and underlying Tenon's membrane is performed using fixation eye tweezers with a working part width of 4.2 mm over the entire width of the tendon from its attachment to the sclera.

The open end of the forceps is placed at the anatomical location of the muscle being operated on, perpendicular to the sclera, 8 mm from the limbus, and the tendon and extraocular muscle are grasped along the course of the tendon. The ends of the fixation forceps are pressed toward each other to form a bundle of the tendon and extraocular muscle with their overlying tissues, lifting and thus fixing the epibulbar tissue grasped by the forceps above the sclera. Xeomin, in the form of a lyophilisate for the preparation of a solution for intramuscular injection, is prepared immediately before administration to the patient by diluting it with 0.9% saline in a volume of 1 ml for the 50 U vial and in a volume of 2 ml for the 100 U vial. Then the drug Xeomin is drawn into an insulin syringe with an integrated needle in the required dosage, one division of the syringe graduation corresponds to 1 unit of the drug.

Depending on the initial angle of strabismus, the following is injected into the internal rectus muscle: at a convergence angle of +7+10 degrees, 2 U are injected; at a convergence angle of +12+15 degrees, 3 U; at a convergence angle of +20+30 degrees, 4 U; at a convergence angle of +31+45 degrees, 5 U.

In the inferior and superior rectus muscles: at 5-7 degrees of vertical deviation, 3 U are injected; at 8-10 degrees of vertical deviation, 4 U; at 11-20 degrees of vertical deviation, 5 U. In the inferior oblique muscle, in case of its hyperfunction, 4 U are injected.

The syringe needle containing the drug is injected transconjunctivally into the internal rectus extraocular muscle, superior rectus extraocular muscle, and inferior rectus extraocular muscle. The needle is inserted into the extraocular muscle bundle collected with tweezers to a depth of 1 mm, as close as possible to the tips of the fixation tweezers, 9 mm from the limbus. After insertion, the needle is advanced through the muscle along its anatomical course for 8 mm toward the orbital apex, after which Xeomin is injected. An increase in soft tissue volume at the injection site is visually noted, and the needle is removed. Tobramycin antibiotic is instilled into the conjunctival cavity, and an aseptic dressing is applied to the eye. The procedure is complete.

The surgical technique for the inferior oblique muscle differs. Due to its deeper anatomical location, visualization of the muscle itself is necessary for injection. A short conjunctival incision of approximately 3 mm is made parallel to the limbus at the inferior-lateral angle of the eye, followed by an incision through Tenon's sheath until the sclera is exposed. Using an eye muscle retraction hook, the inferior oblique muscle is secured and pulled into the visual field within its own intact Tenon's sheath. The needle is inserted into the visualized portion of the muscle, at the junction of its outer and middle thirds, to a depth of 2 mm into the muscle, then advanced parallel to the muscle fibers for 8 mm toward its origin—the inferior-medial orbital rim. Xeomin is then injected at a dose of 4 U. The expansion of the Tenon's sheath is visually noted. The needle is withdrawn, and the muscle is released from the hook. Two interrupted absorbable sutures (7-0 Vicryl) are placed on the conjunctiva. Tobramycin antibiotic is instilled into the conjunctival cavity, and an aseptic dressing is applied to the eye. The procedure is complete.

After surgery and for the next 7 days, antibacterial and antiseptic medications are administered 1-2 drops in each eye, 4 times daily. Children are observed in the ophthalmology department for two days. Subsequently, patients are followed up at 2 weeks, 1, 3, 6, and 12 months after treatment.

The invention is illustrated by the following examples.

Example 1

Patient G., 1 year old. Diagnosis: OU convergent alternating strabismus with a paralytic component, infantile esotropia. Retinopathy of prematurity, cicatricial stage. Aggressive posterior retinopathy of prematurity, surgically treated (twice intravitreal injection of VEGF inhibitors + peripheral retinal laser coagulation).

According to the child's mother, the child complains of a deviation of the eyes toward the nose. Visual acuity is OU - the child can follow objects. Skiascopy:

Ophthalmic status: OU. The anterior segment is calm. Convergence deviation +15 degrees according to Hirschberg, alternating. Partial limitation of outward mobility of the eyeballs of the 2nd degree. The cornea is transparent. The anterior chamber is shallow, the aqueous humor is transparent. The pupil is round, up to 1.5 mm in diameter, after instillation of 0.1% atropine it dilated to 6 mm. The lens and vitreous body are transparent. The fundus - optic disc is gray-pink, the contours are clear. Central vessels: veins are moderately full-blooded, the course is unchanged, arteries are narrowed, the course is unchanged. Reflexes in the macular zone are clear. On the periphery in zone II in the outer sections there are vascular arcades of minimal activity. A circular zone of multiple confluent laser coagulates.

The patient was administered Xeomin as directed. In the operating room, under mask anesthesia with sevoflurane, after preparing the surgical field, an eyelid speculum was inserted, maximizing the palpebral fissure and obtaining wide access to the eyeball. The internal rectus tendon was transconjunctivally grasped with ophthalmic forceps. Using an insulin syringe needle with the required dose of Xeomin, a 3-U dose was injected transconjunctivally into the bundle collected with the forceps, along with the overlying epibulbar tissue, tendon, and internal rectus muscle, as close as possible to the forceps tips, closed under the tendon. An increase in soft tissue volume at the injection site was visually noted. The needle was withdrawn, and the ophthalmic forceps were removed from the tendon. A 0.3% dose of Tobramycin antibiotic was instilled into the conjunctival cavity. The lid speculum was removed, and an aseptic dressing was applied. The procedure was performed in the same sequence on the fellow eye. The patient remained under anesthesia for 5 minutes.

In the postoperative period, a 0.3% Tobramycin solution was instilled into the conjunctival cavity of both eyes 4 times a day for 7 days.

During the two days following surgery, mild conjunctival swelling in the inner corner of the eye was observed. No complications were detected, and the patient was discharged. A two-week examination revealed a decrease in the angle of strabismus with a slight hyperextension of 0-5 degrees (OU deviation according to Hirschberg), which is normal during the period of increasing effectiveness (7-14 days postoperatively).

At follow-up examinations at 3, 6, and 12 months postoperatively, normal horizontal phoria was noted—OU deviation of 0 degrees according to the Hirschberg scale, ocular motility increased, and abduction was largely restored. At the 1-year, 3-month follow-up, intermittent esotropia of up to 0+5 degrees of Hirschberg convergence was noted.

Thus, the magnitude of the primary and secondary angle of strabismus was significantly reduced, while strabismus from the state of tropia passed into the correct horizontal position of the eyes within a period of up to 1 year of observation, conditions were created for the correct formation and development of visual functions.

Example 2

Patient K., 3 years old. Diagnosis: Convergent non-accommodative strabismus, OS with a vertical component, hyperfunction of the inferior oblique muscle, V-syndrome.

OU Retinopathy of prematurity, stage II cicatricial, operated (intravitreal injection of VEGF inhibitors twice OU + peripheral retinal laser coagulation OS). Hyperopic astigmatism of the direct type.

According to the child's mother, there are complaints about the deviation of the left eye towards the nose, and a forced position of the head with a tilt towards the right shoulder.

Visual acuity OD = 0.25 with glasses (cyl + 2.5 ax 95) = 0.6 then n/c.

Visual acuity OS = 0.1 with glasses (cyl + 2.5 ax 80) = 0.3 then n/c.

Skiascopy (mydriasis):

Ophthalmic status: OU. The anterior segment is calm. OU convergence deviation is +20 degrees according to Hirschberg alt, OS hypertropia is 5 degrees, in adduction hypertropia is 20 degrees, V-syndrome. Ocular torticollis - head tilt toward the right shoulder. Positive Bielschowsky test on the left. The cornea is transparent. The anterior chamber is of medium depth, the aqueous humor is transparent. The pupil is round, up to 2 mm in diameter, after instillation of 0.1% atropine, it dilated to 6 mm. The lens and vitreous body are transparent. The fundus - optic disc is pale pink, contours are clear. Central vessels: veins are moderately full-blooded, the course is unchanged, arteries are narrowed, the course is unchanged. Reflexes in the macular zone are clear. On the left - on the periphery of the external section in zone II without vascular activity, a circular zone of multiple confluent laser coagulates.

The patient was administered Xeomin as directed. In the operating room, under mask anesthesia with sevoflurane, after the surgical field was prepared, an eyelid speculum was inserted, maximizing the palpebral fissure and providing ample access to the eyeball. Using an insulin syringe needle with the required dose of Xeomin, a 4-U dose was injected transconjunctivally into the bundle of tissues collected with forceps, covering the epibulbar tendon, and medial rectus muscle. The tips of the forceps were closed under the tendon, and an increase in soft tissue volume was visually noted. The needle was withdrawn, and the ophthalmic forceps were removed from the tendon. To access the inferior oblique muscle of the left eye, due to its deep anatomical location, a short conjunctival incision of approximately 3 mm is made at the inferior-lateral angle of the eye, parallel to the limbus and 7 mm from it. Tenon's membrane is incised until the sclera is exposed. Using an ocular muscle retraction hook, the inferior oblique muscle is fixed and pulled into the field of view within its own intact Tenon's membrane. Xeomin is injected into the muscle at a dose of 4 U. The expansion of the Tenon's membrane is visually noted. The needle is removed, and the muscle is released from the hook. Two interrupted absorbable sutures (7-0 Vicryl) are placed in the conjunctiva. Tobramycin antibiotic is instilled into the conjunctival cavity, and an aseptic dressing is applied to the eye. The procedure is complete. Tobramycin 0.3% antibiotic was instilled into the conjunctival cavity. The eyelid speculum was removed, and an aseptic dressing was applied. The patient remained under anesthesia for 10 minutes.

In the postoperative period, a 0.3% Tobramycin solution was instilled into the conjunctival cavity of both eyes 4 times a day for 7 days.

During the two days following surgery, mild conjunctival swelling in the inner corner of the eyes was observed. The interrupted suture in the inferior-outer part of the left eye was intact, no complications were detected, and the patient was discharged. A two-week examination revealed a decrease in the angle of strabismus (OU deviation of 0+5 degrees according to Hirschberg), and a vertical angle of strabismus of 0 degrees. Follow-up examinations at 3, 6, and 12 months after surgery revealed normal horizontal and vertical phoria (OU deviation of 0 degrees according to Hirschberg), ocular torticollis was completely relieved, and corrected visual acuity in the left eye increased to 0.65.

Thus, the horizontal and vertical angles of strabismus were reduced, while strabismus from the state of tropia passed into the correct horizontal and vertical position of the eyes, visual acuity increased, the correct position of the head was restored, and conditions for the correct formation and development of visual functions were created.

A total of 18 patients with strabismus associated with ROP in the cicatricial phase of the disease, aged from 1 year 1 month to 4 years 5 months (average age 2 years 1 month), were treated by the proposed method. There were 15 patients with convergent strabismus, in which the procedure was performed on the internal rectus muscle of both eyes, of which 2 patients had a convergence angle of +7+10 degrees; 6 patients had a convergence angle of +12+15 degrees; 3 patients had a convergence angle of +20+30 degrees; 1 patient had a convergence angle of +31+45 degrees. In 3 patients in the cicatricial phase of ROP, convergent strabismus of 15 degrees (2 patients) and 20 degrees (1 patient) was combined with hyperfunction of the inferior oblique muscle. Three patients in the cicatricial phase of ROP had vertical strabismus of up to 10 degrees upward (one patient), 15 degrees upward (one patient), and 5 degrees downward (one patient). In all cases, the procedure resulted in symmetrical, even eye alignment, which was maintained for over one year. Complications such as eyeball perforation, conjunctival and Tenon's membrane scarring, anterior segment ischemia, transient upper eyelid ptosis, or decreased tear production were not recorded in any of the cases.

Claims (8)

1. A method for treating strabismus associated with retinopathy of prematurity in the cicatricial phase in children, comprising the administration of a drug based on botulinum toxin type A into the hyperfunctional or hyperfunctional extraocular muscles, where xeomin (hereinafter referred to as the drug) is used as a drug based on botulinum toxin type A, and the dose of its administration is determined taking into account the initial angle of strabismus and the type of hyperfunctional extraocular muscle, while the following is administered: into the internal rectus oculomotor muscle at a convergence angle of +7+10 degrees - 2 U of the drug, at a convergence angle of +12+15 degrees - 3 U of the drug, at a convergence angle of +20+30 degrees - 4 U of the drug, and at a convergence angle of +31+45 degrees - 5 U of the drug; into the inferior rectus oculomotor muscle and the superior rectus oculomotor muscle at a vertical deviation angle of 5-7 degrees - 3 U of the drug, at a vertical deviation angle of 8-10 degrees - 4 U of the drug, and at a vertical deviation angle of 11-20 degrees - 5 U of the drug; into the inferior oblique extraocular muscle – 4 U of the drug; Moreover, the drug is injected into the internal rectus oculomotor muscle, the inferior rectus oculomotor muscle and the superior rectus oculomotor muscle as follows: first, the needle is injected into the muscle to a depth of 1 mm, 9 mm from the limbus, then the needle is advanced along the muscle by 8 mm and to a depth of 1 mm towards the apex of the orbit and the drug is injected; The drug is injected into the inferior oblique extraocular muscle after it has been removed along with Tenon's membrane through an incision in the conjunctiva at the lower outer corner of the eye. First, a needle is inserted into the muscle to a depth of 2 mm at the border between its outer and middle thirds, then the needle is advanced along the muscle by 8 mm and to a depth of 2 mm in the direction of the lower inner orbital margin and the drug is injected. 2. The method according to paragraph 1, characterized in that the introduction of the drug into the internal rectus oculomotor muscle, the inferior rectus oculomotor muscle and the superior rectus oculomotor muscle is performed transconjunctivally, using fixation eye tweezers to fix the muscle. 3. The method according to paragraph 1, characterized in that the introduction of the drug into the inferior oblique extraocular muscle is carried out after its removal through a conjunctival incision parallel to the limbus, 3 mm long.