Conjunctivitis is an inflammation of the conjunctiva, a transparent membrane covering part of the eyeball and the inner part of the eyelids. The conjunctiva contains small blood vessels that look like thin red lines on the sclera (the white of the eye) and, when inflamed, give the eye a reddish appearance. Conjunctivitis is a benign disorder that does not affect vision, but can cause complications if not treated properly.
They are tumours that appear in the conjunctiva, which is the transparent mucous membrane that covers the eyeball from the corneal edge (limbus) to the conjunctival fornix. These tumours can be benign or malignant, pigmented or non-pigmented, and, in some cases, can threaten the patient’s vision and life. They, therefore, require early diagnosis in order for them to be treated appropriately.
The cornea is normally a transparent and regular structure. Various diseases (congenital and acquired) and trauma can cause a focal or diffuse loss of transparency. For various reasons (infection or trauma), scars appear on the cornea. These scars are opaque and make vision difficult.
A corneal ulcer is an injury to the cornea that may become very serious if it is not treated in time. It can be caused by infections infections, infections caused by contact lens use, trauma, the presence of a foreign body in the eye, inadequate closure of the eyelid.
Dry Eye is one of the most frequent pathologies in Ophthalmology, being estimated that 14 to 33% of the world population suffers from this disease; is one of the main causes of consultation in Ophthalmology. Its prevalence increases with age, is more frequent in women, and has a direct impact on multiple activities (work and leisure).
Dry Eye is caused by a deficit lacrimal production or by excessive evaporation of the tears produced; the last is the main factor in about 75% of patients and is due to Meibomius Gland Dysfunction. They are present in large quantities, in the eyelid region, and are responsible for producing the lipid component that strengthens the tear quality, covering the outer surface of the eye. The dysfunction described above is associated with a chronic inflammation present in blepharitis.
The dysfunction of these glands and Blepharitis, leads to the production of a natural tear of poor resistance to evaporation, leading to typical symptoms of stinging, dryness, frequent tearing (more intense during reading or computer tasks), red eye and burning, as well as vision fluctuation and even chronic ocular inflammation.
Keratitis is an inflammation that affects the cornea. The cornea is the most anterior and transparent structure of the eyeball. If it only affects the most anterior part of the cornea (epithelium), it is called superficial keratitis. It is the most frequent. It can usually be cured without after-effects. If it affects deeper layers of the cornea, it is called ulcerative keratitis. This is less common, but can be serious. Occasionally, it produces scarring on the cornea (leukoma), which, if centrally located, can compromise vision.
Keratoconus is an eye disorder in which the central or paracentral area of the cornea progressively thins. Its usual spherical shape becomes conical, causing irregular astigmatism that distorts images, and a subsequent decrease in vision. Keratoconus is one of the main reasons for Corneal Transplant Surgery in young patients; should be diagnosed early in order to be adequately treated with Contact Lenses or corneal surgeries such as "Collagen-Crosslinking" or Intracornean Ring Segments.
Limbal Stem Cell Deficiency:
Limbal stem cell deficiency syndrome means there is no longer a source for corneal epithelial cells. This is replaced by conjunctival epithelial that normally surrounds the cornea and, in these cases, it expands and “invades the territory”, taking advantage of the limbus no longer acting as a barrier to prevent the growth of the conjunctiva. It's usually related to the appearance of Pterygium, Pinguecula or previous Chemical Traumatisms.
A pterygium is an abnormal growth of the conjunctiva over the cornea. It most often occurs on the nasal side of the eye, but can occur on the outer side or on both.
Amniotic Membrane Transplant:
Amniotic membrane transplantation consists of applying a piece of amniotic membrane to the surface of the eye. This piece is usually attached to the tissue by means of fine sutures. There are two different methods of application, depending on the type of injury: dressing or graft.
If there is only one defect in the epithelium (the outermost layer of the cornea or conjunctiva), but the stroma (the layer underneath) is healthy, the amniotic membrane is used as a dressing that covers the entire surface. The growth factors that the membrane contains cause the epithelial cells to begin to grow underneath it. After a few days, the membrane can be easily removed in the doctor’s surgery, leaving no traces.
The amniotic membrane triggers a rapid wound healing process that can last between 2 and 15 days, depending on the eye condition that is being treated. In cases of deeper injury involving loss of the stroma, the membrane is grafted, filling the gap left by the missing stroma. With this method, the cells do not grow underneath, as is the case when the dressing is placed on the epithelium, but do so on top, until the membrane, which gradually becomes absorbed, is replaced.
Grafting involves a slower healing process with the membrane taking several months to be absorbed. During this time, the amniotic membrane can make the eye opaque, which temporarily limits vision.
Conjunctiva Tumor Surgery:
It is the surgical removal of conjunctival tumours, while generating the smallest possible scar and seeking the complete removal of the lesion. In the event of a malignant tumour, this must be sent for anatomopathological examination (biopsy).
Surgery is indicated in all cases of a malignant tumour. If the tumour cannot be completely removed and the biopsy confirms the diagnosis, adjuvant therapy (chemotherapy, radiotherapy) must be determined. If the tumour is benign, surgery is indicated in cases involving a risk for vision. In other cases, it can be observed and monitored clinically.
Patients should not take anticoagulants or aspirin before surgery. The procedure is performed under local anaesthesia and sedation.
Corneal cross-linking involves subjecting the cornea to ultraviolet radiation to strengthen it and slow down deformation caused by keratoconus.
Descemet’s Membrane Endothelial Keratoplasty (DMEK):
It is a partial transplantation procedure that enables the selective removal of a diseased endothelial cell layer and its replacement with a healthy one extracted from a donor cornea.
Dry Eye Treatment:
Conventional treatment includes the use of artificial tears, eyelid cleansing, application of heat and massage on the palpebral area where the glands are situated and, very recently, the application of Pulsed Light to stimulate the best functioning of the Meibomius Glands.
The Pulsed Light treatment was developed in France and Switzerland, using devices for several years to treat skin diseases (Rosacea) through the same concept. The treatment is painless, does not require preparation and is divided into 3 sessions, each during about 10 minutos.
The stimulation of the glands promoted by the Pulsed Light application, associated with maintenance of some local hygiene measures and lubrication, allow an overall improvement of the patients' symptoms, with a clear decrease in the frequency of instillation of lubricating drops, as well as an improvement in the quality of life. The treatment can be repeated after 2 to 3 years, if necessary, to reinforce its effect.
The published clinical results and the personal experience obtained in the clinic, reinforcing the application of this type of treatment, in a subsequent increase in the number of patients, as a result of the excellent results observed.
Intrastromal Corneal Rings:
Intracorneal ring segments are a treatment option in keratoconus. Its implantation through the femtosecond laser assisted technique, allows to change the irregular cornea curvature; irregular astigmatism and high-order aberrations in the patient's image. They are the most complete refractive treatment for keratoconus and the effectiveness and safety index they evidence, are high. They prevent the need to perform a Cornea Transplant.
Limbal "stem cell" Transplantation:
The scleral-corneal limbus is a transition zone, a ring surrounding the cornea, in which the cornea and surrounding conjunctiva join. This peripheral zone of the cornea also contains corneal epithelial stem cells, which, after growing in the limbus, migrate over the cornea from the periphery towards the centre, where they are eventually lost by desquamation.
There are a number of congenital or acquired factors that can seriously damage the limbus and, consequently, the stem cell population, causing a condition known as limbal stem cell deficiency syndrome. Limbal stem cell deficiency is caused when there is no longer a limbal stem cell source for corneal epithelial cells. The result is an invasion of conjunctival epithelial cells over the cornea, which take advantage of the fact that the limbus has ceased to act as a barrier to inhibit the growth of the conjunctiva.
The expansion of the conjunctival epithelium over the cornea causes vision loss, as well as epithelial adhesion problems, corneal erosion and ulcers, chronic inflammation and abnormal blood vessel growth. When the limbal stem cell deficiency has not yet fully developed, it can be treated with eye drops. In severe cases, however, limbal stem cell transplantation is the best option.
Penetrating or Lamellar Corneal Transplantation:
Corneal transplantation (keratoplasty) can be penetrating, when it involves replacing the entire cornea, or lamellar or selective, when only the affected layers are replaced. Therefore, depending on the location of the damage, different lamellar transplantation types are possible:
- Endothelial Corneal Transplantation (DSAEK or DMEK): when the lesion is produced on the endothelium or innermost layer.
- Anterior Corneal Transplantation (DALK): when the lesion is produced in the stroma, which represents 95% of the total thickness of the cornea.
Where the epithelium, the outermost layer, is affected, a corneal stem cell transplantation is required.
Pterygium Surgery with Conjunctival Autograft:
When the pterygium causes discomfort to the patient or enlarges its size to the extent that it approaches or occupies the area of the pupil, causing astigmatism or impairing vision, surgery is necessary.