Complications of cataract
Introduction
Introduction to complications of cataract Complicatedcataract refers to the local lesions in the eye causing local epithelial or internal metabolic abnormalities in the lens, or the inflammation of the local lesions and the degradation of the lens by the denatured product, resulting in lens opacity. In its essential sense, cataracts caused by systemic or ocular local lesions are in the category of complicated cataracts. The morphological characteristics of lens opacity are related to the primary disease. basic knowledge The proportion of illness: 0.003%--0.004% Susceptible people: no specific people Mode of infection: non-infectious Complications: retinal detachment glaucoma
Cause
Complications of cataract
(1) Causes of the disease
Local inflammation of the eye mainly includes chronic uveitis, such as heterochromic iridocyclitis and Still disease (adolescent rheumatoid arthritis) complicated by uveitis; degenerative diseases mainly include old retinal detachment, retinitis pigmentosa , high myopia, chronic glaucoma, etc., another case is intraocular tumor, cataract caused by ischemia and fundus vascular disease, intraocular surgery, such as glaucoma filtration surgery, cataract after retinal detachment surgery, clinically It is not uncommon, and the lens opacity combined with intraocular filling after vitrectomy is more common. In the above cases, iridocyclitis complicated with cataract has the most clinical significance; and retinitis pigmentosa complicated with cataract, morphologically Also very representative.
1. In acute acute seizures of glaucoma with acute angle-closure glaucoma, inflammatory exudate due to segmental iris ischemia accumulates on the surface of the anterior capsule of the lens, causing local metabolic disorders and focal formation under the anterior capsule of the lens. Grayish white spots, strips or plaque turbidity, that is, glaucoma plaques, similarly, long-term application of the miotic agent pilocarpine can be secondary to iritis, resulting in local inflammatory exudation to form a anterior subcapsular opacity.
Through epidemiological investigation, glaucoma is one of the high risk factors for cataract occurrence. The mechanism is not clear. The secondary structure changes of lens capsule protein in glaucoma patients, such as the increase of helix, the decrease of helix structure, cause the capsule to ion. Increased permeability, opacity of the lens, glaucoma complicated with cataract, increased antinuclear antibodies and degraded DNA in plasma and tears, and increased blood-aqueous barrier permeability, suggesting that this may also be the mechanism of glaucoma complicated with cataract. One.
Large-scale long-term epidemiological investigations and basic experimental studies have shown that the transparency of the lens after glaucoma is significantly reduced, which can produce cataracts such as nuclear, cortical, posterior capsular opacity, and obvious inflammation after glaucoma surgery. In the case of complications such as shallow anterior chamber, the incidence of cataract will be higher, and the mechanism may be related to the increase of lipid peroxidation content in the aqueous humor and the decrease of aqueous antioxidant activity in glaucoma.
2. Uveitis acute iris ciliary body inflammation exudation formed after the adhesion can form a basal anterior capsule opacity, while the posterior uveal inflammation itself and the uveal drug glucocorticoid can cause posterior capsule And the posterior cortical opacity, the mechanism may be when the uveal inflammation, inflammatory cells escape a large number of oxygen free radicals leading to lens cells, protein and lipid peroxidation, followed by opacity of the lens.
3. Retinal detachment and surgical retinal detachment may be caused by inflammatory and degeneration products from the thin and epithelial-free lens posterior capsule, forming posterior capsule opacity, epidemiological investigation found that the incidence of cataract in patients with long-term retinal detachment 61.1%, the incidence of cataract after vitrectomy was 60%, 36% of patients with visual acuity decreased significantly, the common cataract morphology was posterior capsule opacity, nuclear opacity or both, the mechanism may be related to vitrectomy It affects the metabolism of the lens. When combined with gas-liquid exchange, long-acting gas injection or silicone oil filling, it is more likely to be complicated by lens opacity, which may be related to lens metabolism and dysfunction caused by direct contact of the filling with the lens.
4. Other retinitis pigmentosa, high myopia, ciliary body tumor, anterior segment ischemia and viral infection can be complicated by opacity of the lens, forming a cataract.
(two) pathogenesis
The mechanism of complicated cataract is not fully understood. It is thought to be related to the inflammatory process interfering with normal lens metabolism. In addition to posterior capsule opacity, complicated cataract can also be characterized by nuclear sclerosis or shallow cup opacity, and cataract caused by different causes. The pathogenesis is not exactly the same.
Prevention
Complications cataract prevention
Actively control the systemic and ocular primary diseases.
Complication
Complications of cataract complications Complications, retinal detachment, glaucoma
Associated with primary diseases that cause cataracts, such as retinal detachment, glaucoma, optic nerve ischemic lesions, etc.
Symptom
Complications, cataract symptoms, common symptoms, lens opacity, vesicular uveitis, glaucoma, phacoemulsification, iris, heterochromatic
1. Complicated cataract associated with anterior segment disease The iridocyclitis is the most common cause of complicated cataract. Typical opacity can occur in the posterior pole of the lens and is also common in the anterior pupillary adhesion (Figure 1). The lesion progresses slowly, such as local inflammation can be controlled, turbidity can be stable for a long time without development. In the recurrent chronic cases, in addition to extensive post-pupil adhesion, often combined with lens capsule thickening or wrinkling, sometimes forming fibrovascular in the pupil area The membrane is tightly adhered to the anterior capsule of the lens. At this time, it is difficult to observe the actual condition of the lens. For example, if the pupil region only forms a fibrous membrane and lacks a vascular component, the opacity of the lens is generally mild. As the disease progresses, the degree and range of turbidity are continuously increased. The enlargement eventually affects the entire lens. During the progression, crystalline substances or calcareous deposits may appear in the lens or capsule, and in the advanced stage, lens shrinkage and even calcification may occur.
The characteristic change of Fuchs heterochromic is iris heterochromia or atrophy, chronic persistent iridocyclitis, cataract occurs in about 70% of cases, ciliary inflammatory disease shows glint in the anterior chamber, cornea There is a large white mutton fat precipitate, the lens opacity progresses slowly, mainly involving the posterior cortex, and the entire lens makes the whole lens opaque in the late stage. Although the course is long, it is not accompanied by post-irisal adhesion.
Glaucomatous flecks appear after the onset of acute glaucoma. The flaky turbidity is located in the surface of the anterior subcapsular transparent area. After several days, the flaky turbidity is broken and separated to form a foamy shape called glaucoma. The histology confirms the actual lesion. It represents the damage of lens epithelial cells. The turbidity can be partially absorbed by the repair process or squeezed into the deep layer by new fibers. From the perspective of clinical treatment of cataract, glaucoma spots have no practical significance, only provide acute exacerbations of glaucoma. evidence of.
2. Concurrent cataract associated with posterior segment diseases
Posterior subcapsular opacity can be combined with any type of posterior uveitis. The development of cataract depends to a large extent on the progression of ocular lesions. Typical conjunctival cataracts begin with subcapsular gyrus and opacity is small particles. It is vesicular and vesicular, densely clustered, forming a loose structure resembling a honeycomb shape, accompanied by a chronic progression of ocular lesions, which can be confined to the posterior pole for a long time, and opacity develops deep into the cortex in the axial region. At the same time, the lens fiber expands toward the equatorial portion in the direction of radiation, and the result is a typical rose-shaped, disc-shaped or star-shaped turbid form. At this time, a slit lamp examination can be found to completely transparent the anterior cortex, the lens nucleus and most of the posterior The cortex has a sharp boundary with the turbid layer. The turbidity is pale yellow, grayish yellow, or colorful reflective, honeycomb loose structure and irregular star distribution, which constitute the unique morphological features of the concurrent cataract.
Ocular degenerative diseases, such as high myopia, retinal dystrophy, retinal detachment, absolute glaucoma, and intraocular tumors, are also common causes of concurrent cataracts. These causes of cataracts, their morphological features and above The description is basically the same, but the course of the disease may be longer, patients with pulseless disease, long-term ischemia of the eye due to obstruction of the aortic branch or systemic arteritis. In addition to systemic symptoms, retinal arteries and veins can be found in the eye examination. Traffic, cataracts are characterized by posterior subcapsular opacity of the lens. With the development of lesions, cataracts can rapidly mature. Thromboangiitis is mainly characterized by inflammation of the deep blood vessels or extremities, thrombosis and vascular occlusion. The cataract is characterized by a lens. Posterior subcapsular opacity is dominant, and the lesion develops rapidly. Due to ocular ischemia, once the cataract is removed, the eyeball atrophy is easily caused. Some posterior eye surgery, such as scleral cerclage, can cause anterior ischemic necrosis as a concurrent It is not uncommon for the lens to become cloudy, and the vitreous cutting After filling an inert gas or silicone oil, leading to more complicated cataract.
Examine
Complications cataract examination
Perform necessary laboratory tests on the primary disease, such as iris sputum inflammation, retinitis pigmentosa, etc.
Including iris corneal angle, electroretinogram, visual evoked potential and other tests.
Diagnosis
Diagnosis and diagnosis of cataract complications
Diagnostic criteria
In summary, the clinical manifestations of concurrent cataract have the following characteristics:
1 There are changes in the characteristics of the primary disease, the lesions are mostly single eyes, but also for both eyes.
2 anterior capsule lesions caused by localized capsular opacity,
The posterior disease of the 3 eyes is characterized by a granular gray-yellow opacity of the posterior capsule of the lens and the posterior subcapsular cortex, and a small number of blisters appear, which can be confined to the axial center, and then gradually expand to the periphery, eventually forming a radial chrysanthemum. Turbid,
4 lens calcification may occur as the turbidity increases, the lens capsule becomes thicker, and there is a white precipitate.
5 high myopia and retinal detachment, mostly nuclear cataract.
Diagnosis can be based on two characteristics of lens opacity: one of the early turbidity has color reflection, and the other is that the opacity and the surrounding cortex are unclear. In addition, the eye is fully examined or according to the history of the eye, other abnormalities in the eye can be found, such as stale Uveitis, corneal lesions, etc., are also important diagnostic criteria.
Differential diagnosis
Early complicated cataract is easy to distinguish from senile posterior cup cataract or traumatic cataract. The posterior cup cataract is crust-shaped, thin and even, surrounded by cloud-like opacity, and there is no typical color reflection. Traumatic cataract along the lens fiber The pattern is feathery and opaque, and there is no typical color reflection. It is sometimes difficult to distinguish from age-related cataract or traumatic cataract. The correct differential diagnosis depends on the history of reference trauma, the age of the patient and the presence of intraocular disease that can cause complicated cataract. Waiting for the situation.
