Treatment of closed-angle glaucoma

Irradiation of the iris and closure of the anterior chamber angle due to the pupillary block lead to a sharp increase in intraocular pressure and the development of secondary glaucoma in patients with uveitis. If there is a violation of the outflow of intraocular fluid due to the pupillary block, it is possible to restore the communication between the anterior and posterior chambers by means of argon- or neodymium IAG laser iridotomy or surgical iridectomy. With the behavior of laser iridotomy, there may be an increase or aggravation of inflammation in the anterior chamber. To reduce the likelihood of this complication, before and after the procedure, active treatment with glucocorticoids should be performed. In contrast to the argon laser, when using neodymium IAG laser uses less energy, and therefore postoperative inflammation is less pronounced. Since with the active inflammatory process, the occlusion of iridotomic holes is possible, then for a stable recovery of the intraocular fluid current, several iridotomies should be performed. Approximately 40% of cases require repeat procedures. To reduce the risk of damage to the corneal endothelium, laser iridectomy should not be performed with severe uveitis in the active phase and edema of the cornea and in the sites of localization of the peripheral anterior synechia.

With unsuccessful laser iridotomy or contraindications to laser treatment, surgical iridectomy is indicated. It has been shown that with uveitis surgical iridectomy is effective if the peripheral front synechia captures less than 75% of the anterior chamber angle. Despite the higher effectiveness of the procedure compared with laser iridotomy, after a surgical iridectomy, severe postoperative inflammation can develop, which is suppressed by the appointment of intensive pre- and postoperative anti-inflammatory therapy. When performing a large surgical iridectomy, slower cataract progression is observed than with laser iridotomy.

When the angle of the anterior chamber is closed due to the rotation of the ciliary body anteriorly in the absence of the pupillary block, it is meaningless to perform laser iridotomy or surgical iridectomy. When closing the angle of the anterior chamber of the eye and increasing the intraocular pressure for this rare reason, immunosuppressive therapy and treatment with preparations that reduce the production of intraocular fluid is carried out. If it is not possible to control the intraocular pressure medically and maintain the closed angle due to the formation of peripheral anterior synechia, an operation aimed at improving the outflow may be required.

It is shown that in connection with acute closure of the angle with the formation of extensive peripheral anterior sinus in the course of goniosinechiolysis, intraocular pressure decreases and the normal structure of the angle of the anterior chamber of the eye is restored. In children and young patients with uncontrolled secondary glaucoma, trabeculodialysis is used to separate the trabeculae from the scleral spur with a goniotomy knife, which allows intraocular fluid to flow directly into the helmet canal.

Due to the temperature influence and the development of laser-induced inflammation capable of inflicting additional damage to the trabecular network, it is not recommended to perform argon laser trabeculoplasty in patients with secondary glaucoma or ocular hypertension due to uveitis.

The main pathological mechanism for secondary inflammatory glaucoma is ocular hypertension. Patients suffering from uveitis are relatively young, and they usually lack the primary pathology of the optic nerve disc, so they note a longer resistance to ocular hypertension, as well as resistance to higher levels of intraocular pressure without surgical intervention. Nevertheless, if it is not possible to control intraocular pressure at the maximum mode, if the optic nerve is damaged or if visual field defects appear, surgical intervention is necessary to normalize intraocular pressure.

Surgical interventions performed in patients with inflammatory glaucoma include trabeculectomy with or without the use of antimetabolites and the implantation of Ahmed, Baerveldt and Molteno tubular drainage. The best way to surgically treat patients with secondary glaucoma has not yet been found.

In carrying out any surgical operations in patients with uveitis, there is a risk of developing after a week of postoperative inflammation. It is estimated that in 5.2-31.1% of cases of surgical treatment of glaucoma associated with uveitis, postoperative inflammation develops or uveitis worsens. The risk of postoperative inflammation is reduced if the eye before surgery is calm. In some cases, there should be no exacerbation of uveitis for at least 3 months before the operation. In order to reduce the risk of postoperative inflammation one week prior to the planned operation, local and / or systemic immunosuppressive therapy is strengthened, which is then gradually reduced in the postoperative period in accordance with the inflammatory response. Perioperative administration of glucocorticoids is carried out intraoperatively. When urgent anti-glaucoma interventions are performed with an active inflammatory process, the disease should be expected to exacerbate, therefore intensive local, high-dose glucocorticoid doses (0.5-1.5 mg / kg) or even intravenous administration may be necessary in the postoperative period.

A good effect is achieved with the use of trabeculectomy in patients with inflammatory glaucoma (73-81%). Nevertheless, the reliability of these data is unknown. When trabeculectomy is performed in patients with uveitis as a result of postoperative inflammation, the overgrowth of the operative aperture accelerates, leading to the absence of the effect of the filtering operation. The efficacy of trabeculectomy in patients with uveitis can be increased through intensive preoperative anti-inflammatory therapy and antimetabolite therapy, for example mitomycin, which is more effective than 5-fluorouracil. In addition to increasing the effectiveness of filtering operations, these drugs increase the risk of postoperative hypotension, external filtration and endophthalmitis, whose frequency after trabeculectomy reaches 9.4%. Often also, cataract progression is observed after operations aimed at improving filtration in inflammatory glaucoma.

If the operations aimed at improving filtration in the treatment of patients with secondary glaucoma are ineffective, drainage implantation is carried out. It was shown that in patients with uveitis, these operations are more effective than repeated trabeculectomy. Postoperative complications, for example, choroidal detachment. Choroidal bleeding and a slit-shaped anterior chamber, with inflammatory glaucoma is more common than with primary open-angle glaucoma.

With unsuccessful medical and surgical treatment as the last possibility of normalization of intraocular pressure, the destruction of the ciliary body is carried out. Cyclocryotherapy. Contact and non-contact laser cycloablation equally effectively reduce intraocular pressure. The main disadvantage of these therapies is the induction of a pronounced inflammatory response and the development of eye subatrophy in about 10% of cases.