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Flat Iris: Causes, Symptoms, Diagnosis, Treatment
Medical expert of the article
Last reviewed: 19.10.2021
[Pathophysiology of flat iris
With a flat configuration, the iris is shifted anteriorly in the root region due to the pressure of large or abnormally located cili-arnies. If the dislocation is sufficiently pronounced, the trabecular network may be closed. In elderly people, a component of the relative pupillary block may also be present.
The flat iris syndrome is determined by occlusion of the trabecular network with functioning peripheral iridotomy laser.
Symptoms of a flat iris
Symptoms, as well as in the secondary closure of the angle, with a relative pupillary block, depend on the rate of closure of the angle. If there is a component of the relative pupillary block, an acute increase in intraocular pressure develops; the symptoms will be the same as in the acute closure of the corner. In most cases, the closure of the angle is slow, there are no symptoms until a significant increase in intraocular pressure or the development of severe changes in the visual fields.
Flat Iris Diagnosis
Usually the eye is calm, the anterior chamber in the center is deep. With compression gonioscopy, the protruding extreme iris ridge, which is protruded anteriorly by cili-arth processes, is determined. Occasionally, with compression, you can see separate processes. Changes in the optic nerve depend on the duration and severity of the increase in intraocular pressure.
Treatment of flat iris
In the absence of closure of the trabecular network with a flat iris, surgical intervention is not required. With a relative pupillary block, laser peripheral iridotomy is indicated.
With the syndrome of a flat iris, it is important to conduct iridoplasty to "move" the iris from the corner. The usual treatment is to apply 16 laser coagulants with an argon green laser at the extreme periphery. The size of the laser coagulum is usually 500 μm, 0.5 s, 200-400 mJ.
As a result, such patients are faced with the question of the need for a filtering operation.