Iritis is an inflammation of the iris of the eyeball. Clinical symptoms are represented by “blurring” of vision, soreness in the eye socket, hyperemia, edema and a change in the pattern of the iris. Diagnostics includes visometry, gonioscopy, perimetry, biomicroscopy, ultrasound of the eye, tonometry, study of the cellular composition of intraocular fluid and the reaction of pupils to light. Conservative treatment is reduced to the appointment of antibacterial agents, nonsteroidal anti-inflammatory drugs, glucocorticoids, mydriatics. Additionally, physiotherapy and vitamins C, A and R are used.
Iritis is a common pathology in practical ophthalmology. It is often considered in the context of anterior uveitis or iridocyclitis. Epidemiological characteristics are directly determined by the etiological variant of the disease. Against the background of systemic lesions (Bekhterev’s disease, Reuter’s disease), iritis develops in 10% of cases. In 30-60%, ophthalmopathology acquires a chronic course. The disease is diagnosed at any age, but it is most often detected in patients 20-40 years old. Inflammation of the iris occurs with the same frequency among men and women. Geographical features of the distribution are not noted.
Inflammation of the iris can develop in isolation or be one of the manifestations of some systemic diseases. Secondary iritis often occurs against the background of Bekhterev’s disease, Reuter’s, psoriasis, Fuchs syndrome, glaucomocyclitic crisis. The main causes of the primary form are presented:
- Injuries of the anterior eye. Inflammation of the uveal tract is a common reaction of the eye tissues to traumatic injury, burn or penetration of a foreign body.
- Infectious diseases. The ability to provoke the development of iritis is noted in pathogens of tuberculosis, toxoplasmosis, syphilis, leptospirosis and brucellosis. The role of group A b-hemolytic streptococcus and gonococcal infection in iris inflammation is being studied.
- Metabolic disorders. The development of pathology potentiates hormonal imbalance in patients with diabetes mellitus, hypothyroidism, hypocorticism in the anamnesis.
- Allergic reactions. Symptoms of iris inflammation often appear against the background of individual intolerance to drugs for installation or retrobulbar administration, systemic allergic reactions.
- Iatrogenic effects. The disease often occurs after surgical interventions on the iris (laser iridectomy, iris plastic surgery).
Antigens of the main histocompatibility complex HLA-B27 play an important role in the mechanism of development of iritis. The relationship between the occurrence of the disease and the effect of endotoxin of gram-negative bacteria has been proved. Autoimmune reactions, which are based on the phenomenon of molecular mimicry, make a significant contribution to the inflammation of the iris of an infectious nature. In this case, the infectious agent has antigenic determinants similar to the cellular elements of the patient. The lesion of the eye membrane and the penetration of pathogens through the hematophthalmic barrier is caused by a cross-immune response.
In the viral genesis of iritis, HLA-B27 antigens form complexes with the antigenic apparatus of the virus, which are recognized by T cells as foreign. This leads to their destruction. Activation of local immunity leads to the development of inflammatory changes in the iris. In response to the synthesis of pro-inflammatory cytokines (histamine, bradykinin, thromboxane A2, interleukins 1, 2, 6, 8), vascular permeability increases. This entails the release of plasma and a small amount of shaped elements into the interstitial tissue, which is manifested by edema and hyperemia. The accumulation of lymphocytes in the thickness of the iris causes the formation of Keppe nodules near the papillary edge and Busacca nodules on the anterior border leaf of the iris.
Irita is characterized by a gradual increase in clinical manifestations. The onset of the disease is often asymptomatic. Patients associate increased symptoms with hypothermia, stress factors, contact with infectious patients or exacerbation of background pathology. The first signs of the disease are increased lacrimation, a feeling of discomfort in the orbital zone. With progression, there is hyperemia of the eyes, swelling of the iris, which is manifested by a decrease in the clarity of its pattern. The pain syndrome increases when pressing on the eyeball.
Often, the first symptom with which patients seek help from a specialist is the presence of hemorrhage areas or a change in the color of the iris. As a rule, the color of the shell becomes lighter, the contour is somewhat smoothed. There is a narrowing of the pupil and a delayed reaction to light. Due to the violation of the refractive power of the eye, visual acuity decreases. Patients complain about the appearance of “fog” in front of their eyes. With prolonged visual loads, asthenopic symptoms develop: burning of the eyes, headache with irradiation into the brow arches, general weakness.
Iritis is characterized by the formation of adhesions between the pupillary margin and the anterior surface of the lens (posterior synechiae), the iris and the cornea (anterior synechiae). The most severe complication of this pathology is secondary glaucoma, the development of which is provoked by the accumulation and organization of exudate in the area of the trabecular network of the eye. With recurrent course of iritis, there is a high risk of developing cataracts. Due to the increased permeability of the vascular wall, the disease can be complicated by subconjunctival hemorrhage, hemophthalmos or hyphema. The detection of purulent contents in the chamber indicates the occurrence of hypopion.
To make a diagnosis, a physical examination is carried out, a special set of instrumental and laboratory research methods is prescribed. Visual examination determines the pericorneal injection, the indistinctness of the iris pattern. The survey plan includes the following methods:
- Gonioscopy. The technique makes it possible to identify turbid fluid (often purulent in nature) in the anterior chamber, morphological changes in the drainage system of the eye.
- The study of the cellular reaction. In order to establish the activity of inflammation, the cellular reaction of the moisture of the anterior chamber is studied. At grade 1, a clear pattern of the iris is determined, at grade 2, individual structures can be differentiated, at grade 3, the examination is sharply difficult, at grade 4, the iris is not visualized.
- Biomicroscopy of the eye. The method makes it possible to detect such objective signs of iritis as swelling, the presence of granulomatous lesions, dystrophic changes in the iris, posterior synechiae.
- Determination of the pupil’s reaction to light. The absence or sharp decrease in the reaction to light is revealed. After the test with mydriatics, the photosensitivity increases.
- Visometry. There is a decrease in visual acuity caused by changes in light refraction in conjunction with a spasm of the accommodation apparatus.
- Perimetry. There is a concentric narrowing of the visual field.
- Ultrasound of the eyes. Ultrasound examination is used to identify morphological changes that stimulate the development of pathology, as well as to visualize secondary lesions of the visual organ (the presence of anterior and posterior synechiae, clouding of the lens).
- Tonometry. Iritis is accompanied by ocular hypo- or hypertension. With an increase in ophthalmotonus, an eye tonography is performed in order to study intraocular hydrodynamics.
From laboratory methods, the determination of antibodies to pathogen antigens by ELISA, HLA typing, a test for the detection of circulating immune complexes, rheumatoid factor and T-lymphocyte populations is shown. The purpose of using these diagnostic methods is to establish the etiology of the disease. If necessary, an additional patergia test, anterior chamber paracentesis and vitreal biopsy are used.
Etiotropic treatment is based on the elimination of background pathology. Detection of even mild symptoms on the part of the organ of vision in infectious and systemic diseases requires consultation with an ophthalmologist. Conservative therapy of iritis includes the use of the following drugs:
- Antibacterial drugs. They are prescribed for the bacterial genesis of inflammation. Before conducting a course of antibiotic therapy, it is necessary to determine the sensitivity of pathogens to drugs.
- Antiviral agents. They are indicated with the established viral origin of the pathology. To achieve the effect, systemic and local (instillation, parabulbar injections) therapy is used.
- Nonsteroidal anti-inflammatory drugs (NSAIDs). The purpose of the application is to stop active inflammation. With low efficiency or generalization of the process, the appointment of glucocorticoids is indicated.
- Mydriatics. Drugs that dilate the pupil are used to prevent the formation of anterior synechiae. Mydriatics are prescribed only with normal or reduced intraocular pressure.
- Vitamin therapy. Vitamins A, C and R are used throughout the treatment period.
- Physical therapy. When posterior adhesions are detected, fibrinolysin, mydriatics and papain are injected using electrophoresis. After the acute inflammatory process is stopped, electrophoresis with aloe extracts and lidase is prescribed.
Prognosis and prevention
The prognosis for life and working capacity is favorable. Specific prevention of iritis has not been developed. Non-specific preventive measures are based on the timely diagnosis of damage to the eyeball in systemic and infectious pathologies. Persons working in production must use personal protective equipment (glasses, helmets). Patients suffering from metabolic disorders (hypothyroidism, diabetes mellitus, hypocorticism) or who have undergone surgery on the iris for the last two years should be examined by an ophthalmologist 2 times a year for preventive purposes.