Corneal dystrophies are a group of degenerative diseases affecting the cornea, which is the most important and strongest lens of the eye. It is that small piece of transparent tissue that we see first. The cornea has the characteristic of being transparent: if something damages it and takes away its transparency, it affects the patient, his visual quality.
Corneal dystrophies can be superficial, intermediate, and deep types. Deep corneal dystrophies are those that mostly affect the patient because they are the most common and, above all, they attack the endothelium, which is the inner part of the cornea. The endothelium is the carpet of cells that covers the inner part of the cornea itself that, practically, determines its life. The metabolism of the cornea is given by these small cells that line the inside; these cells of the corneal endothelium are about 3000 cells per square millimeter at birth and have the characteristic of regenerating very badly, that is if they are killed or destroyed they do not reform. Hence, the importance of endothelial test and microscopy to examine them, count them and judge them from the morphological point of view, and above all to see if a normal decay in the quantity of these cells is accompanied by the presence of dystrophy, that is instead of cells, islets are formed in which the cells themselves are practically absent.
This is the typical endothelial dystrophy in which microdroplets are formed resembling microdroplets of wax, on the inside of the endothelium.
It is important to recognize this type of pathology because it can take away one’s eyesight, though usually not in a sudden way. It is a very slow process that cannot completely take away the eyesight in the course of life, but it is very important to recognize it because given the number of cataract surgeries that are done in the Western world and how soon the cataract is operated on, corneal dystrophy is placed at the intent of cataract surgery. What does it mean? The patient can be told that he has corneal endothelial dystrophy, meaning “the further you do the cataract, the better”, because knowing fully well that cataract surgery destroys a part of these endothelial cells that are already diseased, cataract surgery is then advised to be delayed and removed as much as possible later in time.
Nowadays, it can be exactly the opposite because thanks to the technologies that we have available, including viscoelastic materials that defend the corneal endothelium during cataract surgery, modern technologies with ultrasound phacoemulsifiers and femto lasers, are all technologies that allow you to perform cataract surgery with minimal damage to the endothelium, that is: the examination is done before the cataract surgery, the endothelial cells are counted, the examination is repeated and after the cataract surgery, the procedure can then reach a minimum loss of endothelial cells, perhaps even as little as 100/200 cells per square millimeter.
This is very important because it serves to guarantee the patient the possibility of having his corneal endothelium available for life; therefore, in the presence of dystrophy of the endothelium of the cornea, this condition must be addressed by the machines that we have at our disposal. The endothelial microscopy must be performed at each eye examination and the endothelial cells must be checked. When it is determined that there is an onset of cataract that begins to have a certain consistency, with the presence of an endothelial cell disease, the cataract itself must be removed, with modern techniques, to save the most possible cells of the endothelium.