keratomalacia
Introduction
Introduction to corneal softening Corneal softening is a kind of corneal melting and necrosis caused by vitamin A deficiency. The entire cornea dissolves and collapses due to secondary infection, ending with corneal staphyloma. This disease is more common in infants and young children. Both eyes are involved at the same time. Diarrhea and chronic digestive tract diseases, improper artificial feeding, measles, pneumonia and other febrile and consumptive diseases, as well as "abortion" when suffering from diseases are common causes of vitamin A deficiency. The early conjunctival goblet cells disappeared, the epithelial cells were hyaline degeneration, and pigmentation. The surface of the epithelial cells became flattened and thickened, and the nucleus disappeared, which was wavy and keratinized. The dry spots contain meibomian gland secretions, epithelial debris, fat, dried bacilli, etc., which are rough and uneven due to keratinization of epithelial cells, and have a foamy appearance. The early changes of the cornea are similar to the conjunctiva, while the late keratinized epithelial cells fall off, the anterior elastic layer necrosis disappears, the parenchymal layer edema, leukocyte infiltration and necrosis, and may be associated with anterior chamber empyema. basic knowledge The proportion of sickness: 0.01% Susceptible people: more common in infants and young children Mode of infection: non-infectious Complications: corneal ulcers corneal staphyloma
Cause
Causes of corneal softening
Insufficient intake of vitamin A (25%):
Vitamin A intake is not sufficient to maintain the minimum requirements in the body, such as artificial feeding or weaning food mismatch, malnutrition; or due to fever, wasting disease, lack of parental health knowledge, inappropriate "taboo", such as measles , pneumonia, etc.
Inadequate absorption and consumption of vitamin A (30%):
Absorption of vitamin A, children with digestive tract diseases, such as gastroenteritis, indigestion, dysentery, etc., resulting in vitamin A can not absorb. Too much consumption, the child grows too fast, or consumes too much during the illness, the demand for vitamin A is large, and the lack of state.
Pathological changes (15%):
The early conjunctival goblet cells disappeared, the epithelial cells were hyaline degeneration, and pigmentation. The surface of the epithelial cells became flattened and thickened, and the nucleus disappeared, which was wavy and keratinized. The dry spots contain meibomian gland secretions, epithelial debris, fat, dried bacilli, etc., which are rough and uneven due to keratinization of epithelial cells, and have a foamy appearance. The early changes of the cornea are similar to the conjunctiva, while the late keratinized epithelial cells fall off, the anterior elastic layer necrosis disappears, the parenchymal layer edema, leukocyte infiltration and necrosis, and may be associated with anterior chamber empyema.
Prevention
Corneal softening prevention
1. Strengthen publicity and education, popularize maternal and child health knowledge, reasonably feed, correct partial eclipse habits, and enable infants and young children to receive reasonable feeding.
2, when infants and young children suffering from chronic wasting diseases, gastrointestinal diseases and hot sexually transmitted diseases, in addition to active treatment of the original open the door to see the mountains, and should properly supplement enough nutrients, to prevent unprincipled "tabge", such as the discovery of children If you want to blink your eyes, you should have an eye examination to find early treatment and prevent the virus from getting worse.
Complication
Corneal softening complications Complications corneal ulcer corneal staphyloma
The development of the disease will occur corneal epithelial shedding, matrix necrosis, ulceration, anterior chamber empyema, cornea can be quickly perforated, iris prolapse, light healing to form adhesive corneal leukoplakia; severe cases can evolve into eyeball atrophy or corneal staphyloma and blindness.
Symptom
Symptoms of corneal softening common symptoms corneal reflex disappearance corneal reflexes corneal sensory reduction
1. The child is thin, wilting, dry and rough skin, accompanied by diarrhea or cough;
2. Night blindness;
3. The corneal conjunctiva is dry, gradually aggravated, loses luster, and the conjunctiva produces wrinkles. The conjunctiva on both sides of the cornea forms a triangular epithelial keratinized plaque, gradually opacity of the cornea, and finally the entire cornea dissolves and necrosis, and a large iris escapes, and then forms a grape swollen;
4. Combined infection, anterior chamber empyema.
Examine
Examination of corneal softening
A full history of medical history and careful eye examination are not difficult to diagnose.
Diagnosis
Diagnosis and differentiation of corneal softening
Diagnose based on
1. A history of vitamin A deficiency such as fever-consuming disease, improper artificial feeding or chronic diarrhea.
2. The typical clinical manifestations described above.
3. Serum vitamin A content is low.
4. Urine sediment is positive for keratinized epithelial cells.
Differential diagnosis
The early appearance of the disease is called the liver deficiency, and when the external eye is not obvious, it needs to be differentiated from the high wind. The patient with high wind and eye has no discomfort, the appearance is good, and the fundus change is not obvious at first. With the increase of age, the lesions gradually become obvious, the visual field begins to shrink, and the night blindness is also aggravated year by year, but the white eyes, the black eyes and the whole body have no hoarding.
