Secondary anterior chamber perfusion and vitrectomy for second-stage intraocular lens suture fixation

In recent years, with the extensive development of vitrectomy, aphakic eyes after vitrectomy are a type of postoperative residual. The second phase of intraocular lens implantation is the most ideal method to improve the visual function of such patients. Because the vitreous in the eye has been cut, it is easy to cause low eye during the second phase of intraocular lens implantation.

In recent years, with the extensive development of vitrectomy, aphakic eyes after vitrectomy are a type of postoperative residual. The second phase of intraocular lens implantation is the most ideal method to improve the visual function of such patients. Because the vitreous in the eye has been cut, the second phase of intraocular lens implantation is likely to cause low intraocular pressure and related complications. From 2001 to 2002, 20 cases of posterior chamber intraocular lens suture fixation with posterior chamber perfusion and vitrectomy were performed. The satisfactory results were obtained after operation.

1 Materials and Methods 1.1 Clinical data collected 20 cases of aphakic eyes after vitrectomy, 15 males and 5 females, aged 25 to 50 years old, with an average of 34.21 county hospitals (Yang Qizhi). All of the posterior segment of the eye were treated with vitrectomy, and there was no intraocular lens after operation. The anterior and posterior capsules were ruptured and lost support function. Among them, 15 cases of ocular trauma, 3 cases of vitreous hemorrhage, 2 cases of dislocation of the lens. Eye trauma was accompanied by 5 cases of intraocular foreign body.

1.2 Suspension type intraocular lens was used as the surgical method, and iris type intraocular lens was selected for those whose iris defect was more than 1/2. Anesthesia application 1% ercaine numbness, every 5 minutes - times, continuous eye four times. Open the sputum, cut the conjunctiva from the limbus, cut the sclera straight into the 1.5mm layer after the limbus, and separate it into the transparent cornea 1mm. Make a anterior chamber puncture above the corneal margin or on the forehead. In the clear cornea below the corneal margin, a perfusion needle was made with a puncture knife at 0 mm. The perfusion needle was inserted, and the anterior chamber was perfused after fixation. The drip bottle used for the perfusate was kept at a height of 60 cm. The upper limbal incision was pierced into the anterior chamber with a triangular knife and expanded to the diameter of the implanted intraocular lens. The bulbar conjunctiva was cut under the limbus, and the sclera was cut at 1.5 mm posterior to the superior and inferior limbal margins. The double-needle and double-wire double-wire were inserted into the needle from the transparent cornea and passed through the upper and lower lamellar scleral incisions. . Use a small hook to pull the wire out of the upper incision and ligature the wire into the small hole in the top of the intraocular lens. The intraocular lens is implanted into the eye, and the polypropylene threads on both sides are slowly pulled to make the intraocular lens horizontal. The crystal sputum is fixed in the ciliary sulcus and sutured to fix the suture. The upper plate incision was sutured intermittently with a 10-0 polypropylene line, the perfusion needle was removed from the anterior chamber of the iliac crest, the conjunctiva was sutured, and 20,000 units of cedar and 2 mg of dexamethasone were injected under the conjunctiva. Antibiotic eye drops were applied.

2 Results 2.1 See the attached table. Preoperative and postoperative visual acuity. Comparison of visual acuity. Pre-eye index. Preoperative and postoperative visual acuity improved one week after surgery. The visual acuity was higher than that of preoperative visual acuity. 10 eyes accounted for 50% of the 0.3 or more. 2.2 Complications One patient had a slight bleeding in the front of the vitreous and was absorbed after 2 weeks. There were 2 cases of corneal edema, which improved after 3 days with corticosteroids.

3 Discussion of ocular trauma, foreign bodies in the ball and diseases that cause vitreous hemorrhage During the vitrectomy, the crystals are often removed together. After the operation, the intravitreal vitreous cavity is completely filled with aqueous humor. When the intraocular lens is implanted in the second phase, the aqueous humor overflows the eye, causing the intraocular pressure to be extremely low, especially the case of requiring the second phase suture of the intraocular lens. Low and medium intraocular pressure is prolonged, which may lead to intraocular hemorrhage, complications such as omentum and choroidal detachment until eyeball atrophy. Many scholars try different surgical methods to solve it. It can be said that how to maintain intraocular pressure during surgery to prevent aqueous outflow is the key to successful surgery.

The anterior chamber intraocular lens is placed on the surface of the iris, and the intraocular lens is not required to be fixed by the suture. The operation time can be shortened, but because it is directly in contact with the iris and the angle of the eye, it is close to the cornea, and secondary glaucoma and corneal endothelium decompensation may occur. More serious complications such as iritis. Placement of the anterior chamber intraocular lens is not suitable for every patient.

The posterior chamber intraocular lens is located behind the iris and belongs to the normal physiological position, and has little damage to the intraocular tissues such as the iris and the anterior chamber. Due to the improvement of microsurgery technology of physicians, the complications caused by human factors in posterior chamber intraocular lens suture fixation are significantly reduced, so it is widely used in the rupture of posterior capsule of the lens. 167. Currently, there are two posterior chamber intraocular lens suture fixation. One method, 1 is to complete the intraocular lens suture fixation operation by perfusion of the ciliary body flat portion to maintain intraocular pressure. This method adds time and difficulty of surgery and the incidence of retinal and choroidal detachment. 2 After the corneal incision is made with a tunnel slab incision, Helon is injected into the front chamber before the aqueous humor overflows, and it fills the entire anterior chamber. After the aqueous humor is pressed to the iris, the water is prevented from overflowing. However, in this method, the amount of Helon injection must be more, and the amount of Helon residual in the eye after surgery increases, which inevitably causes the symptoms of inflammatory reaction to increase.

Insertion of the perfusion needle into the anterior chamber and intraocular lens implantation under the anterior chamber can avoid the shortcomings of the above methods. The advantages are as follows: 1 The anterior chamber perfusion operation is simple, does not damage the posterior segment of the eye, and the flat portion of the ciliary body Perfusion must puncture the sclera and choroid, causing intraocular hemorrhage during operation, and the choroid and retinal detachment are increased. 2 Because the corneal incision is tunnel-type, the intraocular water in the eye is less spilled, and the anterior chamber perfusion is always kept open, ensuring that the intraocular pressure is always maintained in a stable state. The low intraocular pressure occurs only when the intraocular lens is implanted into the eye. very short. Corneal edema occurred in 2 of the patients in this group. The postoperative corneal edema was considered as postoperative, and corneal edema did not occur after the dropper height was reduced.

When the intraocular lens fixed suture is passed through the sclera, it should avoid repeated needle insertion to prevent damage to the blood vessels in the ciliary body and cause intraocular hemorrhage. In this group, one case was initially examined for a small amount of bleeding in the vitreous cavity after 2 weeks. Self-absorbed.

After the vitrectomy, the second phase of intraocular lens suture fixation is a new trial of the second phase of intraocular lens implantation after vitrectomy. It is proved that the method is safe and reliable, with less postoperative complications. Promotion and application.

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