What Causes Anterior Uveitis?

Anterior uveitis is the most common type of uveitis, accounting for more than 50% of the total uveitis, and can manifest as acute, chronic, granulomatous, and non-granulomatous inflammation. Anterior uveitis can be roughly divided into three categories:

Basic Information

English name

anterior uveitis

Visiting department

Ophthalmology

Common symptoms

Eye pain, photophobia, tears, blurred vision

Contagious

no

Clinical manifestations of anterior uveitis

Symptoms

Patients may have eye pain, photophobia, tearing, and blurred vision. When a large amount of fibrin exudates in the anterior chamber or reactive macular and optic disc (papillary) edema, it can cause a significant decrease in vision, concurrent cataracts and subsequent In severe glaucoma, vision can be severely reduced.

2. Signs

(1) Ciliary congestion or mixed congestion Ciliary congestion is the congestion of superficial scleral blood vessels located around the limbus, and is the most common sign.

(2) Posterior corneal deposits Inflammatory cells or pigments are deposited on the posterior surface of the cornea and are called KP. Its formation requires the simultaneous presence of corneal endothelial damage and inflammatory cells or pigments.

(3) Anterior chamber flare is caused by the breakdown of the blood-aqueous aqueous barrier function and the protein enters the aqueous humor. It appears as a white light beam during slit lamp inspection. Therefore, anterior chamber flashes do not necessarily represent active inflammation.

(4) Anterior chamber cells In pathological conditions, inflammatory cells, red blood cells, and nuclear pigment cells of tumor cells can appear in the aqueous humor. Uveitis is mainly inflammatory cells, and gray-white dust particles of uniform size can be seen on slit lamp examination. The near iris faces upward and the near cornea moves downward. Inflammatory cells are a reliable indicator of inflammation in the anterior segment of the eye.

(5) Iris changes There may be changes such as iris edema and unclear texture.

(6) The pupil changes due to ciliary muscle spasm and continuous contraction of the pupil sphincter during inflammation, which can cause pupil shrinkage. Adhesion after the iris can not be pulled apart, and the appearance of multi-shaped pupils often appears after dilation, such as plum blossom, pear shape. Irregular shape. If 360-degree adhesion occurs in the iris, it is called pupillary atresia; if the fiber membrane covers the entire pupil area, it is called pupillary atresia.

(7) Lens changes Pigments can be deposited on the front surface of the lens during anterior uveitis, and ring-shaped pigments can be left on the surface of the lens sheet when the adhesion behind the fresh iris is pulled apart.

(8) Changes in the vitreous body and the posterior segment of the eye In iridocyclitis and anterior ciliary body inflammation, inflammatory cells can appear in the anterior vitreous body, and patients with simple irisitis may occasionally develop reactive macular edema and optic papillary edema.

Pre uveitis examination

1. Non-granulomatous anterior uveitis with alternating episodes of acute recurrent eyes should be examined by HLA-B27 antigen typing and sacroiliac joint radiographs;

2. Anterior chamber empyema and multi-type skin lesions should be examined by skin allergic reaction test, fluorescein fundus angiography, HLA-B5 antigen or B51 antigen typing;

3. Patients with granulomatous anterior uveitis, diarrhea, blood in the stool, and other lesions should undergo bowel endoscopy and biopsy;

4. The fluorescein fundus angiography is of great value in determining macular cystoid edema associated with anterior uveitis and mild edema of the optic disc. Many acute anterior uveitis can cause reactive fundus changes.

Anterior uveitis diagnosis

Diagnosis can be made according to the clinical manifestations of the patient. Since a variety of systemic diseases can cause or accompany such uveitis, determining the etiology is of great value in guiding treatment and judging the prognosis. Therefore, a detailed history of acute anterior uveitis should be asked. Laboratory tests include routine blood tests, erythrocyte sedimentation, and HLA-B27 antigen typing. Corresponding etiological examinations are performed on those suspected to be infected by pathogens.

Anterior uveitis treatment

The principle of treatment is to dilate pupils immediately to prevent adhesions behind the iris, and to quickly anti-inflammatory to prevent eye tissue damage and complications. For highly suspected or confirmed pathogen infections, appropriate anti-infective treatment should be given. For non-infective uveitis, systemic medication is generally not required because topical medication can reach an effective concentration in the anterior segment of the eye.

Ciliary muscle paralysis agent

It is an essential drug for the treatment of acute anterior uveitis, and it should be administered as soon as it develops. The most commonly used is post-matropine eye ointment, which can effectively prevent the occurrence of post-iris adhesions. However, the posterior dilatation and ciliary muscle paralysis of posterior matotropine are less effective than atropine. Therefore, atropine eye ointment can be given for acute and severe anterior uveitis.

2. Glucocorticoid therapy

Commonly used formulations are suspensions or solutions of hydrocortisone acetate, flumethasone acetate, prednisolone acetate, and dexamethasone phosphate. For severe acute anterior uveitis, dexamethasone phosphate solution can be given once every 15 minutes, and then changed to once an hour after 4 consecutive times. After several days of continuous application, the number of eye drops can be gradually reduced according to the resolution of inflammation. For patients with reactive optic papillary edema or macular cystic edema, dexamethasone tenon injection can be given. For Tenon subcapsular injection, or reactive macular edema and papillary edema in bilateral acute anterior uveitis, prednisone can be administered orally, taken in the morning, and reduced after 1 week. The general treatment time is 2-4 week.

3. Non-steroidal anti-inflammatory drugs

Non-steroidal anti-inflammatory drugs mainly exert their anti-inflammatory effects by blocking metabolites of arachidonic acid such as prostaglandins, leukotrienes, and the like. It has been proven that acute anterior uveitis, especially after surgery or trauma, involves the involvement of arachidonic acid metabolites, so eyedrops such as indimemethacin and diclofenac can be given.