band keratopathy
Introduction
Introduction to banded keratopathy Bandshaped corneal degenation (also known as corneal band opacity and calcific band keratopathy) is a corneal lesion caused by calcium deposition in the corneal epithelium. Often divided into two types of primary and secondary. basic knowledge The proportion of sickness: 0.0001% - 0.005% Susceptible people: no specific people Mode of infection: non-infectious complication:
Cause
Cause of banded keratopathy
Intraocular injection of silicone oil (20%) after vitreous:
In recent years, it has been reported that intravitreal injection of silicone oil can cause this disease. The reason may be due to the circulation disorder of the aqueous humor. It is also suggested that the skin is prednisolone or dexamethasone phosphate. Long-term topical application of steroid hormone drugs can also promote the disease by increasing the phosphate concentration of tears and corneal stroma.
Trauma (15%):
Secondary to traumatic injuries, long-term exposure, caused by chemicals such as mercury, may also be related to long-term contact with rabbit hair, steam and smoke. Atypical corneal strip lesions can be seen in glaucoma patients who use long-term use of miotic agents. This type of mimetic contains phenylmercuric nitrate preservative.Systemic disease (20%):
Secondary to systemic lesions are more common in increased blood calcium, hyperparathyroidism, vitamin D poisoning, sarcoidosis, kidney disease and leprosy.
Bilateral diffuse fat deposition (20%):
Primary subjects are associated with bilateral diffuse fat deposition.
Eye lesions (10%):
Secondary to ocular lesions are more common in the late stages of severe eye disease, such as iridocyclitis, absolute glaucoma, corneal stroma, and atrophy of the eye.
Prevention
Banded keratopathy prevention
Clinical prevention should start from the cause. For patients with these diseases, active anti-infective treatment and anti-virus alternate eye drops should be given to reduce the occurrence of this disease, and appropriate vitamin A supplementation.
Complication
Banded keratopathy complications Complication
Can be complicated by corneal deposition (KP), iris atrophy and elevated intraocular pressure.
Symptom
Symptoms of banded keratopathy common symptoms eye pain, photophobia, tearing, dry corneal opacity
The disease can occur in all ages, mostly monocular, or both eyes, the lesions develop slowly, can be more than 10 years, the initial corneal opacity is very slight, the naked eye is not easy to find, the opacity is obvious when it is exposed in the cleft The cornea, which is equivalent to the level of the front elastic membrane, has calcium-white or white turbid plaques in the vicinity of the nose and the temporal side, respectively. There is a narrow 1 mm narrow transparent band between the turbid area and the limbus to separate it. The central side of the turbid area is relatively ambiguous and can slowly expand toward the center. After many years of change, the turbidity at both ends can be connected, and it is fused into a banded lesion of 3 to 5 mm wide, sometimes accompanied by the growth of new blood vessels. The slit lamp can be seen to show turbid calcium. There is a transparent small hole in the plaque, which is the passage of the trigeminal nerve through the front elastic membrane. The turbid area is composed of the subepithelial, the front elastic membrane and the sediment of the shallow layer of the matrix. The turbid plaque can be gradually dense and thickened to make it upper. Epithelial bulge, rough and uneven, and even epithelial erosion, causing irritations such as photophobia, tearing and eye pain, the visual acuity of patients with advanced disease can be significantly reduced.
Examine
Examination of banded keratopathy
1. Detection of calcium, magnesium, phosphorus and other elements in the blood.
2. Renal function tests estimate renal function status.
3. Laboratory tests for rheumatoid arthritis.
4. Pathological examination The main pathological changes were in the anterior elastic membrane and epithelial layer. In the early part of the anterior elastic membrane, there was focal eosinophilic change with punctate calcareous deposition. The basement membrane of epithelial cells showed basophilic coloration. The disease progresses to the center, the anterior elastic membrane is further calcified and fractured, and the shallow matrix can be similarly changed. The anterior elastic membrane is broken and replaced with avascular tissue, and the hyaluronic substance enters. Calcareous and calcified fragments can be inserted. The epithelial cell layer makes it thick and thin, and often has subepithelial fibrous tissue hyperplasia. Some cases have proved that this pathological change can develop to the deep layer, and even may involve the corneal endothelium. The electron microscopic examination shows that there are different sizes in the front elastic membrane. The high electron density of calcified globules and spots, some of the peripheral calcified globules have a denser electron density than the central part, while others have a denser center and a lighter periphery.
5. X-ray film: the examination of the joints in the presence of arthritis symptoms.
Diagnosis
Diagnosis and diagnosis of banded keratopathy
According to the history and typical morphological changes of the cornea, combined with the results of the auxiliary examination can be diagnosed.
