1. What is a corneal age ring?
Corneal senile rings are lipid-like deposits in the stroma of the peripheral part of the cornea, white in color, about 1mm wide, appearing initially in the upper and lower part of the cornea and gradually developing into a ring. It is common in the elderly, and almost all people over the age of 80 have senile rings. Senile rings are usually a degenerative change with a genetic predisposition, but may sometimes be a manifestation of hyperlipoproteinemia or elevated serum cholesterol. No specific treatment is needed.
2. What congenital developmental abnormalities can there be in the cornea?
There are many types of congenital abnormalities of the cornea. Common ones include: congenital large cornea, congenital small cornea, flat cornea, spherical cornea, scleralized cornea, congenital corneal opacity, corneal dermatoma, etc. These congenital anomalies are usually accompanied by developmental abnormalities in other parts of the eye and poor vision, and some patients need corneal transplantation to improve their vision.
3. Which eye diseases are prone to rejection of corneal transplantation?
The following factors increase the likelihood of rejection after corneal transplantation: (1) the presence of neovascularization in the patient’s corneal stroma, as neovascularization makes it easier for immune cells to reach the graft and recognize and attack the allogeneic antigen. (ii) Large graft slices are susceptible to rejection because they carry strong effective antigens and are close to the patient’s corneal edge. (iii) The patient’s own sensitivity is higher and also predisposes to rejection. ④Several other factors such as inflammation, ocular congestion, and other surgical operations after grafting may also induce rejection. Specifically, corneal lesions with severe neovascularization (such as corneal leukoplakia, acid and alkaline burns), uncontrolled corneal inflammation, herpes simplex keratitis, and patients who need a second corneal transplant after the first corneal transplant rejection are more prone to rejection after corneal transplantation.
4.How to prevent and treat rejection after corneal transplantation?
The prevention and treatment of rejection of corneal transplantation should be based on both prevention and treatment. Rejection after corneal transplantation is generally unlikely to occur within 10 days, and with adequate corticosteroids, rejection rarely occurs within 2-3 months after surgery. The peak time of rejection is 4-18 months after surgery, after which the incidence decreases. Rejection is often induced by stitch removal, corticosteroid reduction and cold, and the main symptoms are vision loss. The main symptoms are loss of vision, bloodshot eyes, photophobia and tearing, and clouding of the corneal graft. If you have any of these symptoms, you should immediately visit our keratoconus specialist for follow-up.
For the treatment of rejection after corneal transplantation, the main clinical measures are: ① Application of corticosteroids: this is the most important drug for the treatment of rejection, in the process of application, we should adhere to the principle of adequate amount, rules and slow discontinuation, and increase the amount of medication after the rejection, and we should pay attention to the complications that may cause the increase of intraocular pressure. ②Application of cyclosporine A: This is an effective immunosuppressant and is generally used after glucocorticoid treatment is ineffective. ③Some other drugs, such as prostaglandin inhibitors, anti-inflammatory pain and aspirin, have some therapeutic effect on immune rejection, and cytotoxic immunosuppressants, such as azathioprine and cytarabine, also have some application, but they must be used with caution under the guidance of an internist because they may cause severe bone marrow suppression and systemic infection. ④If rejection has occurred and treatment is ineffective and the graft piece is cloudy, a second corneal transplantation can be considered.
5.What are the precautions after corneal transplantation?
Corneal transplantation itself is only a part of corneal transplantation, post-operative treatment and self-care are important elements of corneal transplantation that cannot be ignored.
1.Regular review: once a week after discharge, after one month if there is no special condition, it can be once a month, and after the corneal suture is removed, it will be reviewed once every three months to reduce the long-term postoperative complications. Medication guideline: Demerol eye drops, 4 times a day; 1% cyclosporine eye drops, 4 times a day; Demerol eye ointment, once a day at bedtime. 3 times a day after 1.5 months, 2 times a day after 3 months, then reduced to 1 time after 2 weeks, and completely discontinued after 4 months.
2, the time of corneal suture removal: penetrating corneal transplantation sutures generally in six months to a year after surgery; lamellar corneal transplantation generally in 2 to 3 months after surgery, the specific time review by the doctor to determine.
3, pay attention to the occurrence of rejection; rejection often occurs 1~2 months after surgery, but some patients also have rejection several years after surgery; therefore, if the patient feels eye redness, pain, sudden vision loss, cloudy corneal graft piece, go to the hospital immediately.
4.If you cannot go to our hospital in time, you should immediately go to the local hospital for consultation and treatment, and it is better to return to our hospital for follow-up if possible. The general treatment is: Dexamethasone eye drops, every hour; 1% cyclosporine eye drops, every 2 hours; Dexamethasone eye ointment, once a day before bedtime; pars plana injection of methylprednisolone 20 mg, every 3 days, or subconjunctival injection of dexamethasone injection 2 or 5 mg (every other day); at the same time, hydrocortisone 100~200 mg dissolved in 500 ml or 1000 ml of glucose solution intravenously. About 7 days later can be changed to oral hormone for a period of time according to the restoration of transparency of the transplantation piece, the eye continues to drops, but the number of times gradually reduced.
5, when dropping eye drops the dropper tip should not touch the corneal graft sheet, more than two kinds of eye drops should be used alternately, each time a few minutes apart, to ensure the concentration of drugs in the eye. Eye drops should be placed in a cool and light-proof place.
6, dietary guidance: appropriate nutrition, enhance the body’s resistance, eat more fruits and vegetables, in order to keep the bowel movement smooth. Eat less spicy and oily food.
7.Activities and rest.
① Pay attention to eye hygiene, do not rub your eyes, wear protective glasses when you go out to avoid touching the operated eye.
② Do not swim, prevent infection, avoid sunlight and hot compresses, and protect the corneal graft.
③ Avoid heavy physical work for one year after surgery, and full repair is required for three months.
④ The graft piece is insensitive and easily injured within one year, so care should be taken to avoid friction. If you belong to patients with herpes moniliformis, you should pay attention to prevent cold, upper respiratory tract infection and overwork after surgery. Do not smoke to prevent the recurrence of keratitis.