Keratoconus is, to date, the leading cause of keratoplasty.
The keratoconus is the most usual pathology that has required more transplants, especially among young patients. Although, Güell warns that in a significant number of countries, the main cause is switching from keratoconus to regrafts. The specialist explains that this change is happening thanks to new treatments’ incursion such as cross linking. This technique can stop the keratoconus evolution and corneal deformation, which reduces the percentage of patients with this alteration in need of a transplant.
Anterior lamellar keratoplasty reduces rejection risk
There is no doubt that anterior lamellar keratoplasty (DALK) is one of the most discussed technique among cornea specialists because it is the most indicated in the major part of patients that require a corneal transplant –except in cases with a previous problem, such as a perforation–. Dr Güell claims that the ideal candidates for this technique are those with healthy and intact posterior corneal layers whose cornea does not visually work correctly. Another huge advantage of DALK is that, unlike the total keratoplasty, the corneal endothelium – leading cause of keratoplasty rejection – is not grafted.
DSAEK and DMEK, two techniques head of debate
When it comes to posterior keratoplasty, the two leading techniques of the debate are DMEK and DSAEK. As the ophthalmologist explains, when 15 years ago surgeons started performing those two procedures, clinical results obtained were better in cases that were operated with DMEK technique. Moreover, the ophthalmologist says that this trend keeps up nowadays and better visual quality is obtained when it is used because the technique itself consists of transplanting the same extracted tissue, keeping the corneal structure exactly the same.
The advantages of DMEK
The specialist explains that DMEK technique has experienced many surgical improvements, which allowed young surgeons to practice this procedure. However, the most significant improvements of this technique are a greater speed when it comes to the lenticle placement and a significant decrease of rebubling tax, approximately from 1 to 2% for the major part of surgeons.
The OCT, a useful tool when visualization is limited
Dr Güell affirms that the OCT is a tool that helps performing DMEK procedure, and it is very useful when the view through the microscope is not good enough. In those cases, the OCT helps distinguishing the positioning of the air. This technology also gives additional information that the surgeon is able to obtain in a direct view with either through the microscope or with a slit lamp inside the microscope.
Corneal regeneration advances
The difficulty of finding a corneal tissue to transplant is one of the specialists’ concerns. Currently it is known that the cornea has 3 main layers: a central layer (stoma), the external layer (epithelium) and the interior (endothelium). Güell notes that, nowadays, artificial stomas are easier to obtain. Furthermore, the culture of epithelial cells of the corneoconjuntival surface has improved significantly. Despite the good results, IMO specialist warns that the biggest challenge consists on the substitution and the creation of endothelial cells, a goal that investigation laboratories all around the world are trying to achieve. For the ophthalmologist, obtaining this corneal layers artificially would mean “a before and an after in the keratoplasty surgery”.