RU2180546C2 - Method for treating infantine cataract cases - Google Patents

Abstract

FIELD: medicine. SUBSTANCE: method involves full-scale circular dissection of the lens anterior capsule using YAG-laser to produce circular capsule defect. The anterior capsule is removed with lens mass using suction-irrigation method. The posterior capsule is retained. EFFECT: enhanced optical and functional effectiveness; reduced risk of traumatic complications; avoided secondary cataract occurrence. 1 tbl

Description

 The invention relates to medicine, namely to pediatric ophthalmology, and is intended for differentiated laser microsurgical treatment of congenital cataracts, taking into account the peculiarities of their clinical forms, leading to increased efficiency and less trauma in the removal of congenital cataracts in children.

 At present, the generally accepted method for removing congenital cataracts in children is microsurgical extracapsular extraction (Khvatova A.V. Results of cataract extraction surgery in schoolchildren for blind and visually impaired children. Scientific notes of the State Research Institute of Glmholtz Diseases issue 8, "Cataracts", 1963, 128-135).

 Well-known features of congenital cataracts: thinness and unevenness of the thickness of the anterior capsule, lack of a nucleus, the presence of milky masses, calcifications (Khvatova A.V. Congenital cataracts. In the book "Diseases of the eye lens in children", Leningrad, 1982, p. 47-90) . Therefore, a complete dissection of the anterior lens capsule produced by a microsurgical instrument during this operation is very difficult and not always feasible with some forms of congenital cataracts.

 At the same time, the remains of the anterior capsule incompletely excised and not removed from the eye in children often (42.3%) lead to the formation of secondary cataract and the need for repeated intervention (6.7-76.9% - Khvatova A.V., Arestova N. H. Features of the clinic and microsurgical tactics for secondary cataracts in children.-Ophthalmological Journal, 1980, 5, p. 35-38).

 The development of laser technologies in ophthalmology made it possible to introduce into the practice of extracapsular cataract extraction in adult patients with age-related cataracts the laser stage of dissection of the anterior lens capsule using an YAG laser, which consists of an YAG laser anterior capsulotomy followed by traditional microsurgical removal of the nucleus and lens masses, which is the closest analogue of the invention (Nugaeva N. R. Laser anterior capsulotomy and nucleoablation in microsurgical treatment of cataracts - Auto eferat diss candidate of medical sciences, Saratov, 1996, -... 20)..

 Clinical features and polymorphism of congenital cataracts in children (thinness and unevenness of the thickness of the anterior capsule, lack of a nucleus, the presence of milk masses, calcifications, etc.) do not allow the use of the YAG laser anterior capsulotomy technique proposed by Nugaeva N.R. in pediatric ophthalmology. for age-related cataracts.

The difference of our invention from the closest analogue lies in the features of the method of YAG laser anterior capsulotomy:
the use of differentiated energy parameters for various clinical forms of congenital cataracts, taking into account their features,
full circular dissection of the front capsule, without leaving jumpers,
removal of a fully dissected anterior capsule by aspiration, rather than a surgical instrument,
removal of the lens masses with the microsurgical method of aspiration-irrigation.

 The technical result of the invention is to prevent the development of secondary cataracts and postoperative complications.

 The technical result is achieved using a dosed YAG laser (YAG laser anterior capsulotomy) in combination with a microsurgical aspiration-irrigation method for removing lens masses together with the anterior capsule.

 Using the YAG laser technique of dosed anterior capsulotomy allows you to make a guaranteed complete dissection of the anterior capsule of the lens, to avoid leaving flaps. Complete removal of the anterior capsule improves the conditions of the stage of the operation - microsurgical removal of the lens masses. The absence of a dense nucleus, the predominance of “soft” lens masses with congenital cataracts in children determine the feasibility of using the aspiration-irrigation method of microsurgical removal of the lens masses in children. The lens masses usually become turbid after exposure to the YAG laser, which greatly facilitates their removal and is an advantage of the proposed method.

 Accurate dosed excision of the anterior capsule by YAG laser capsulotomy in combination with aspiration-irrigation of the lens masses in most cases allows the integrity and intactness of the transparent posterior lens capsule to be preserved. In children, maintaining the integrity and intactness of the posterior lens capsule is fundamentally important, because opening it on the immature eye of a child, often having a concomitant pathology of the vitreous body, etc., often leads to serious, irreversible complications (hernias of the vitreous, vitreocorneal adhesions, Irwin-Gass syndrome, macular degeneration, secondary glaucoma, retinal detachment).

 The absence of remnants of the anterior capsule of the lens, lens masses, and the intactness of the posterior capsule are a reliable prevention of secondary cataract formation in children.

The method is as follows:
1. Laser phase: YAG laser anterior capsulotomy.

 Use, for example, a laser system VISULAS - YAG (yttrium aluminum garnet activated by neodymium). The radiation wavelength of 1064 nm, the pulse duration of 2-3 ns, the diameter of the focal spot 30-50 microns. The number and energy of impulses are determined depending on the clinical form of congenital cataract (see table).

 Other forms of congenital cataracts - central, spindle-shaped, anterior axial, embryonic, star-shaped, cataract of sutures, coronary, punctate and others - usually do not require surgical removal.

 20 minutes before the laser intervention, to achieve the maximum drug mydriasis, a mesatone solution of 1% - 0.2 is administered under the conjunctiva of the eyeball.

 The YAG laser anterior capsulotomy is painless, therefore, children over 5 years old are performed under local anesthesia (two-time installation of 0.5% dicaine solution 2-3 minutes before the procedure). Children under 5 years of age and non-contact older children undergo laser surgery under general anesthesia.

 In the laser cabinet, a Abraham contact lens is put on the child’s eye for precise focus and safety. The dissection of the front capsule by a YAG laser is performed in 1 session by a circular full dissection technique. The focus beam of the YAG laser is focused on the anterior lens capsule 1.0 mm from the edge of the pupil. Throughout the entire circumference (with a diameter of 6-7 mm, 1 mm from the pupil edge), laser pulses are applied to the surface of the anterior capsule of the lens — perforations. Individually selecting the power and number of pulses (see modes above), they achieve the formation of a ring-shaped defect in the surface of the anterior capsule, without leaving jumpers.

 After the laser stage, the 2nd stage of treatment is carried out - microsurgical: the suction removal of the dissected anterior capsule is carried out simultaneously with the removal of the lens mass by the method of aspiration-irrigation according to A.V. Khvatova (Khvatova A.V. Removal of congenital cataracts in children. In the book: Diseases of the eye lens in children. Leningrad. 1982, p. 74-84).

 In the operating room, under conditions of anesthesia, the eyelids and the eyeball are immobilized. The palpebral fissure is dilated using an eyelid extender. Immobilization of the eyeball is provided by the application of the frenum suture on the superior rectus muscle. Two corneal incisions are made at a distance of 0.5-1 mm from the inner border of the limb in the upper segment. The flap of the anterior capsule dissected by a YAG laser is not removed with a surgical instrument, but with an irrigation-aspiration method. Through one surgical incision of the cornea, the flap of the anterior capsule dissected by the laser and the lens masses are aspirated. At the same time, an irrigation fluid is introduced into the anterior chamber through a second incision, which ensures the preservation of a constant depth of the anterior chamber and the level of intraocular pressure. The lens masses usually become cloudy after exposure to the YAG laser, which facilitates their removal. The posterior capsule often remains intact. They remove it with a microcystotome only if there is intense congenital opacification.

 The final stages of the operation are: narrowing the pupil with 3-4 times instillation of a 2% solution of pilocarpine hydrochloride, restoring the anterior chamber by introducing sterile air, applying nodal immersion sutures to both corneal incisions. Under the conjunctiva, 0.2 ml of dexamethasone and an antibiotic solution (gentamicin - 0.2), gordox 0.3 ml are administered. A 20% solution of sodium sulfacyl-sodium or 0.3% solution of chloramphenicol is introduced into the conjunctival sac. A sterile binocular dressing is applied.

 Example: Patient J. 2 years. Diagnosis at admission: OS-congenital, hereditary zonal cataract of the II-III degree, obstructive amblyopia.

 Visual acuity at receipt of OS = 0.01 is not corrected. IOP = 23 mm Hg Art.

 Ultrasound: PZO = 23.4, the vitreous is acoustically transparent, detachment is not determined.

 ERG: OI-subnormal, VIZ on flash: OI-amplitude and lability are normal.

 Operated with the above combined laser-surgical method.

 Under anesthesia, a complete circular dissection of the anterior capsule was performed with a YAG laser. The laser exposure on the anterior lens capsule consisted of 40 pulses with an energy of each from 2.5 to 5.0 mJ, the total energy of 122 mJ. Complications during and after laser exposure were not observed. Then, by the aspiration-irrigation method in the operating room, the anterior lens capsule and lens masses were removed: a thin transparent front capsule dissected by a laser and the lens masses that were cloudy after laser exposure were aspirated. The rear capsule is transparent, intact, preserved. The postoperative course is reactive, without complications.

 Discharged from the hospital on the 10th day after the operation with visual acuity in the operated eye 0.1 s + 10.0 D = 0.3. The pupil area is clean, the posterior capsule is perfectly transparent, there are no remains of the anterior capsule and lens masses, there is a live pupil reaction to the light, there is no synechia. Vitreous body and fundus without pathology. Conducted 2 courses of laser pleoptic treatment. After 1 year of observation, visual acuity with correction increased to 0.6-0.7, there is no synechia and secondary cataract - the posterior capsule retains transparency.

 Example: Patient A. 5 years. Diagnosis at admission: OI-congenital complete mild cataract, obstructive amblyopia.

 Visual acuity at admission OI-0.05, is not corrected, IOP OI = 16-17 mm Hg

 Ultrasound: PZO OD-27.2, OS-23.8, the vitreous is acoustically transparent, retinal detachment is not determined. ERG: OI - without pathological changes.

 Under general anesthesia on the OS, a complete circular excision of the anterior capsule by a YAG laser was performed. The laser exposure on the anterior lens capsule consisted of 30 pulses, with an energy of each pulse of 1.2-2.5 mJ, the total energy of 74 mJ.

 Complications during and after laser exposure were not observed. Then, in the operating room, the child underwent microsurgical removal of the anterior capsule dissected by the laser and clouded lens masses using an aspiration-irrigation method. Postoperative course without complications. The pupil area is clean, there are no remains of the anterior capsule and lens masses, the posterior capsule is perfectly transparent, there is a live pupil reaction to light. The fundus without pathology. The patient was discharged from the hospital on the 10th day after the operation with visual acuity on the operated eye OS = 0.1 s + 10.0 D = 0.5. Conducted 1 course of laser pleoptic treatment. After 8 months, visual acuity increased with correction to 0.9, the posterior capsule retains transparency, there is no secondary cataract and synechia.

 Thus, the method allows to increase optical and functional efficiency, reduce trauma, improve the conditions for microsurgical removal of any clinical forms of congenital cataracts, exclude the left flaps of the anterior capsule, provide more complete removal of the lens masses, increase the chances of maintaining the integrity of the posterior capsule, i.e. prevent the formation of secondary cataracts in children.

Claims (1)

 A method of treating congenital cataract in children, including dissecting the front capsule with a YAG laser, characterized in that the dissection is performed until a circular defect of the capsule is obtained, and the front capsule is removed simultaneously with the lens masses by aspiration-irrigation without removing the back capsule.

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