Lens-associated uveitis

Introduction to lens related uveitis The disease has multiple names in the literature, either based on pathogenesis or pathological features, but they do not represent all the characteristics of such diseases, and are confusing in use, so the use of lens-related uveitis is proposed. This name, but at least indicates that uveitis is caused by lens factors. basic knowledge The proportion of illness: 0.002% Susceptible people: no special people Mode of infection: non-infectious Complications: cataract open angle glaucoma

Lens-related uveitis etiology

(1) Causes of the disease

It has been confirmed that lens antigen induces uveitis. Animal experiments have shown that after immunizing animals with lens antigen and Freund's complete adjuvant, puncturing the lens capsule can induce uveitis, and human lens-related uveitis occurs mostly in After eye penetrating injury or cataract surgery, it is speculated that the immune response caused by the massive exposure of lens protein antigen may lead to uveitis. Recently, some anaerobic infections may promote the occurrence of uveitis through the adjuvant effect, lens protein. It is also possible as a chemotactic substance of monocytes to cause an inflammatory reaction by recruiting monocytes.

(two) pathogenesis

The mechanism by which lens antigens induce inflammatory responses is not fully understood. In the past, lens proteins were thought to be isolated from the immune system. Recent studies have denied this view and found that there is active immunity to lens proteins in vivo. Immunization is tolerant and does not cause an inflammatory response.

1. Destruction of lens antigen tolerance

The destruction of lens antigen tolerance is the key to the occurrence of lens-related uveitis. The current study found that the serum anti-lendrocyte antibody titer in patients with lens-associated uveitis is increased, the patient's skin test is positive, and the lymphocytes have a lens antigen. The active proliferative response, in some patients with bilateral lens allergic endophthalmitis, suggests that autoimmune responses to lens antigens are an important cause of lens-related uveitis.

2. The role of infection

Infection or infection with infection can cause lens-related uveitis. At the beginning of this century, it was observed that patients with lens-related uveitis often had obvious purulent infection, and 5% of the lens allergic endophthalmitis accompanied by obvious bacteria. Infection, some suspicious lens-related uveitis may also be associated with anaerobic infections (such as P. acnes infection). Some people think that this anaerobic bacteria may act as an adjuvant, leading to damage and resistance to immune tolerance. The formation of autoimmune reaction of lens protein, in fact, the rats immunized with this anaerobic bacteria and exogenous lens protein can obtain similar effects with Freund's complete adjuvant, and the T cell immune response caused by infection may also indirectly affect Residual lens components, leading to inflammatory reactions, and other experiments have shown that S. aureus injection into the rat anterior chamber, causing lens damage, can cause performance similar to lens allergic endophthalmitis, but at this time in the aqueous humor The bacteria have been cleared, which indicates that the infection plays a role in the development of lens-related uveitis.

3. The role of lens protein toxicity

The toxicity of lens proteins also plays a role in the occurrence of lens-related uveitis. Some scholars have proposed the view that lens toxicity causes lens-related uveitis. The so-called toxicity means that there is no pre-existing immunity or trauma. The ability to directly trigger inflammation, according to which the lens protein can induce inflammation through several mechanisms:

1 crystal protein or its decomposition product can act as a chemotactic substance of monocytes, allowing inflammatory cells to reach local;

2 The extracellular matrix is a reservoir of cells, cytokines, growth factors and other biological response regulating substances, and the residual lens protein may play such a role to "absorb" cytokines, thereby causing inflammation;

3 bacterial toxins may contribute to the occurrence of lens-related uveitis, there is evidence that bacterial lipopolysaccharide can aggravate or induce lens-related uveitis in rats or rabbits, bacteria that enter the eye during surgery may be hidden in the residual In the lens protein, which causes lens related uveitis.

Lens-related uveitis prevention

The entry of the lens nucleus and cortex into the vitreous is an important cause of lens-related uveitis. Therefore, avoiding the lens nucleus and cortex entering the vitreous body and removing the vitreous into the vitreous during surgery is an important measure to prevent lens-related uveitis and enter the vitreous. Small lens fragments (not more than 25% of the nucleus) can be observed and treated with drugs, but complete anterior vitrectomy should be performed to ensure that there is no vitreous incarceration at the surgical incision and that the vitreous does not adhere to the intraocular lens. Corticosteroids and non-steroidal anti-inflammatory drugs eye drops are treated with eye treatment and closely observed for several months; for large lens fragments (more than 25% of the nucleus) entering the vitreous, such as the lens fragments are soft, anterior vitrectomy, cortical removal Surgery, and remove the lens of the vitreous lens, can be implanted in the posterior chamber of the ciliary sulcus intraocular lens, may also consider implantation of the anterior chamber intraocular lens, if the cortex into the vitreous is hard, then the anterior vitrectomy and cortex removal should be performed And should perform a complete posterior vitrectomy, which is not suitable for such patients. Lens implantation.

Reducing the stimulation of ocular tissue by improving the intraocular lens material can prevent or reduce the inflammatory reaction after intraocular lens implantation. In fact, with phacoemulsification and intraocular lens implantation, postoperative uveitis has occurred. Significantly reduced.

Detailed systemic and ocular examinations of patients with uveitis before surgery to determine the type of uveitis, and effective treatment, choose the appropriate timing of surgery, postoperative uveitis aggravation or recurrence can be avoided .

Lens-related uveitis complications Complications, open angle glaucoma

Secondary open-angle glaucoma occurs due to lens cortical dissolution of allergic cataract, often associated with lens allergic endophthalmitis.

Lens-related uveal inflammation symptoms Common symptoms Eye pain granuloma pseudo anterior chamber empyema uveitis congestion unilateral fundus appearance of meat... Monocular eye shadow

Clinically, lens-related uveitis can be manifested in three types: total uveitis or endophthalmitis, chronic anterior segment inflammation and bilateral chronic inflammation.

1. Whole uveitis or endophthalmitis

Patients often have a history of recent cataract surgery or a history of penetrating ocular trauma. Inflammation in individual patients can occur only a few months after surgery. There may be a history of lens material entering the vitreous during surgery. Patients with severe inflammation may have eye pain, vision. Decreased or severely decreased, ciliary congestion or mixed hyperemia, a large number of inflammatory cells in the anterior chamber, significant anterior chamber glint and cellulose-like exudation, and even anterior chamber empyema, sometimes pseudo anterior chamber empyema (large Leukocytes and lens materials are mixed together. The vitreous cells may have inflammatory cells and turbidity. The fundus is invisible. Although such inflammation may involve the posterior segment of the eye, it is usually located in the anterior segment of the eye. This inflammation is not easy to be associated with infective endophthalmitis. The difference, if not properly treated, inflammation will quickly increase.

2. Chronic anterior segment inflammation

More manifested as granulomatous inflammation, the appearance of sheep fat KP, post-iris adhesion, anterior chamber glint and anterior chamber inflammatory cells, local glucocorticoids can reduce inflammation, but as long as the residual lens material is not absorbed or not removed This inflammation is difficult to completely disappear. If the correct treatment is not given, there may eventually be a restorative reaction such as iris neovascularization and ciliary membrane formation, which is difficult to distinguish from other types of anterior uveitis.

3. bilateral chronic inflammation

This type is relatively rare, manifested as bilateral long-term mild anterior uveitis, such as KP, mild anterior chamber flash, a small amount of anterior chamber inflammatory cells.

Examination of lens associated uveitis

1. Anterior chamber puncture examination room water cells

The increase in eosinophils in the aqueous humor of the lens allergic endophthalmitis accounts for more than 30% of all inflammatory cells. The aqueous humor of the lens-soluble glaucoma contains macrophages that phagocytose the lens cortex.

2. Immunological examination

At present, the diagnostic value of the skin test and lens antibody examination of the lens cortex is different, because the skin test and lens antibody are not specific to the lens uvitis, but also can be seen in patients with uveitis after lens injury and cataract in normal people. Patients, even lens antibodies and skin test positives can also be seen in normal people.

3. Pathological examination

The pathological morphology of lens allergic uveitis is mainly of three types:

Type I: phacoanaphylactic endophthalmitis (PhE), which is the type first described by Verhoeff and Lemoine. It has strong clinical inflammatory symptoms and its pathogenesis is the Arthus-type reaction of antigen-antibody immune complexes. Among the lens fibers, there are neutrophil infiltration and macrophages that phagocytose the lens cortex, and also eosinophils and plasma cells, sometimes indistinguishable from infectious lesions, and form a special form of granuloma in the late stage of the lens. An inflammatory reaction ring surrounds the lens cortex, that is, there is a granulomatous reaction zone near the lens cortex, which contains large mononuclear cells, epithelial cells, multinucleated giant cells, macrophages; outside the ring is a fibrous blood vessel; It is a plasma cell band; the outermost layer is surrounded by lymphocytes, and the nearby iris ciliary body has lymphocytes, plasma cells, eosinophils, and fibroblasts, etc., often non-granulomatous anterior uveitis, and the anterior chamber has multiple nuclei. Infiltration of cells and monocytes, in a few cases in the late stage, ciliary membrane formation, retinal detachment and other changes.

Type II: macrophage reaction, the most common type of this type, can occur in all cases of lens damage, characterized by macrophage accumulation in the lens capsule damage site, common with foreign body macrophages, early Macrophages are large and abundant in cytoplasm, including PAS-positive granules. In the longer-term cases, a small number of macrophages surround the lens capsule, and lymphocytes, plasma cells and macrophages in the anterior part of the iris and ciliary body. The diffuse mild infiltration is also a non-granulomatous inflammatory manifestation. If inflammation disappears, there is fibrous scar tissue in the lens capsule defect.

Type III: granulomatous lens-induced uveitis (GLU), and some cases are granulomatous anterior uveitis, which is similar to the typical histopathology of PhE in the vicinity of the damaged lens. Type has granulomatous inflammation in the uveal tissue, sometimes the tumor and ciliary body have tumor-like thickening, granulomatous inflammation mainly close to the lens cortex, and invade the posterior iris and ciliary body, reaching the flat part backwards, Epithelial cell populations, mixed with lymphocytes, macrophages and epithelial cells, some have PAS-positive granules in the cytoplasm, and there are a large number of plasma cells which are different from sympathetic ophthalmia.

It can be seen from the above table that GLU and PhE are mostly anterior segment inflammation, and the anterior segment inflammation of GLU is more obvious. It is granulomatous inflammation, and there are many epithelial cell infiltration and destruction of retinal pigment epithelial cells, but there is no granulation between lens fibers like PhE. Invasive cells, both plasma cells are more common, pathologically should be differentiated from sympathetic ophthalmia (SO), SO is mainly for uveitis, the posterior segment is more than anterior segment inflammation, there are not many plasma cells, and there are Dalen- Fuchs (DS) nodules, PhE can also be seen in patients with sympathetic ophthalmia, these cases not only the uveal injury but also the performance of lens capsule rupture, so both can be combined.

4. The fissure examination can confirm the anterior uveal inflammation and aqueous humor, whether there is residual lens cortex, and intraocular pressure measurement.

Diagnosis and identification of lens related uveitis

Uveitis is easy to diagnose, but it is sometimes difficult to determine the lens-related uveitis. Although the eyeball penetrating injury, the history of cataract surgery is helpful for diagnosis, but the diagnosis often requires histological examination. Ultrasound examination reveals vitreous There are residual lens fragments, aqueous or vitreous cytology and culture to help eliminate infectious endophthalmitis.

Differential diagnosis

Lens-related uveitis should be associated with endophthalmitis after intraocular penetrating injury or cataract surgery, sympathetic ophthalmia, idiopathic uveitis, ankylosing spondylitis associated with uveitis, Reiter syndrome Uveitis, uveitis associated with psoriatic arthritis, uveitis associated with inflammatory bowel disease, uveitis associated with juvenile chronic arthritis, tuberculous uveitis, syphilitic uveitis Isophase identification.

1. Eyeball penetrating injury or cataract surgery after endophthalmitis

There are 2 types, one is acute intraocular inflammation (injury), often occurs 2 to 7 days after surgery (injury), manifested as red eyes, eye pain, photophobia, tearing, decreased vision, swelling of the eyelids, conjunctiva Edema, corneal edema and infiltration, a large number of inflammatory cells in the anterior chamber, anterior chamber empyema or fibrinous exudation, vitreous opacity, retinal vein inflammation, retinal necrosis, etc.; another type is delayed type (injury) Endocrine, which occurs several weeks or months after cataract surgery or eye penetrating injury, has mild symptoms, may have redness, eye pain, photophobia, tearing, decreased vision, etc., may appear sheep fat KP, anterior chamber flash Hui and anterior chamber inflammatory cells, according to the above manifestations, post-traumatic or postoperative acute endophthalmitis is generally not difficult to distinguish from lens-related uveitis, but post-exposure (injury) endophthalmitis is easy to be associated with the lens Uveitis is confused, the main point of identification is delayed ocular surgery (injury), endophthalmitis can appear granulomatous deposits on the surface of the lens, cream spots in the lens capsule, even empyema in the capsular bag, histological examination and Intraocular specimen culture can determine the diagnosis.

2. Lens-related bilateral uveitis

It mainly occurs after cataract extraction and eyeball penetrating injury of the lens. The eyes are followed by the disease, mainly characterized by mild to moderate anterior uveitis, occasionally causing intermediate uveitis and posterior segment involvement, vitreous and anterior The inflammatory cells in the room are mainly neutrophils, and the inflammation does not recur after the lens material is removed.

3. Sympathetic ophthalmia

Occurred in various eye penetrating injuries and internal eye surgery, both eyes often have the same onset or short interval, mainly manifested as total uveitis, can also be manifested as posterior uveitis or anterior uveitis, can cause choroidal thickening , serous retinal detachment, Dalen-Fuchs nodules can occur in the elderly, the sunset-like fundus changes, the cells in the vitreous and aqueous humor are mainly lymphocytes, according to the above characteristics, they can generally be distinguished.

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