Corneal edema
Edema is the accumulation of fluid in any organ or tissue of the body that can trigger a significant inflammatory process. Corneal edema is a condition present in the cornea which can occur as a result of fluid retention in the cornea, which can be caused by various factors such as contact lenses or eye surgery.
Corneal edema can cause significant visual disturbances such as loss of visual acuity. The appearance of colored halos in the lights is the most characteristic sign of this condition. Before any symptom of corneal edema, it is important to go to the ophthalmologist immediately to avoid any more serious complications.
Corneal edema
Edema is the accumulation of fluid in any organ or tissue of the body that can trigger a significant inflammatory process. Corneal edema is a condition present in the cornea which can occur as a result of fluid retention in the cornea, which can be caused by various factors such as contact lenses or eye surgery.
Corneal edema can cause significant visual disturbances such as loss of visual acuity. The appearance of colored halos in the lights is the most characteristic sign of this condition. Before any symptom of corneal edema, it is important to go to the ophthalmologist immediately to avoid any more serious complications.
What is a corneal edema?
The cornea is the tissue that protects the iris and lens and allows light to enter from the outside into the eye. Corneal edema is a corneal condition that occurs when there is fluid retention in the cornea
This causes the tissue inflammation that opacifies the layers of the cornea, due to their thickness and as a coexistence of a lack of hydration. This condition is considered a progressive and irreversible dystrophy.
The cornea is composed of six layers that follow the order from outside to inside: epithelium, Bowman's membrane, stroma, dua layer, Descemet's membrane and endothelium. When corneal edema affects the epithelium, the cornea appears opaque and reflects light irregularly, affecting the patient's vision.
Causes
Corneal edema may or may not be caused by different factors. The main ones are:
- Eye trauma.
- Sudden increase in intraocular pressure which may be caused by a angle-closure glaucoma.
- Inflammation in the anterior area of the eye as uveitis y keratitis.
- Rejection of cornea transplant.
- Degenerative eye diseases such as keratoconus, Funchs endoepithelial dystrophy and congenital endothelial dystrophy.
- Excessive or incorrect use of contact lenses.
- Cataract surgery complication.
Symptoms of corneal edema
The symptoms of corneal edema can vary depending on how advanced the condition is. Symptoms can be, but are not limited to:
- Visual disorders
- Blurry vision.
- Decreased visual acuity.
- Very strong pain.
- Appearance of colored halos around the light sources.
- Photophobia or sensitivity to light.
- Excessive tearing.
- Ocular redness
Types of edema
The types of corneal edema are:
Corneal edema due to primary endothelial defect
It occurs when the corneal edema is genetic origin. It is characterized because it appears in the stroma and is irreversible.
Corneal edema due to secondary endothelial defect
This edema is what occurs when the edema becomes a condition secondary to disease or treatment and triggers a bullous keratopathy. This is usually caused by penetrating wounds, ocular inflammation, complications in cataract surgery, endothelial alterations, among others.
Due to increased intraocular pressure
This edema is an acute condition that causes formation of small cysts in the epithelium. It can be caused by a sudden increase in intraocular pressure due to angle-closure glaucoma.
By epithelial alteration
It is common for it to happen as a consequence of a trauma or erosion to the eye. This type of corneal edema affects the epithelium, the outermost layer of the cornea.
Diagnosis
To diagnose corneal edema it is necessary examine eye structure. The eye exams that should be performed are:
- Slit lamp eye study.
- Fluorescein angiography to detect the presence of leaking blood capillaries and determine the amount of extravasated fluid.
- Optical coherence tomography to study the entire eye in detail, including the macula of the retina.
- Pachymetry to know the thickness of the cornea.
- It is also important to check for vitreous detachment in the anterior chamber of the eye.
Corneal Edema Treatment
The treatment depends exclusively on the cause that originates the alteration. If fluid buildup in the eye is mild, the option of draining the fluid with hypertonic eye solutions or ointments.
Other treatment options depending on the cause of the corneal edema they are:
- Glaucoma o Elevated IOP: treatment consists of keeping eye pressure levels controlled through medications such as brimonidine and beta-adrenergic blockers.
- Contact lenses: In this case, the patient must discontinue the use of contact lenses or change to ultra-thin lenses.
- Eye operation: when the edema is very severe it will be necessary to perform a Descemet endothelial keratoplasty.
- Complicated cataract surgery: If the edema does not go away on its own after a couple of weeks, saline drops or ointments are prescribed to reduce the swelling of the cornea.
