With the advent of intrastromal ablation technique lasik eye surgery finds a new dimension. It has added something like an insurance policy against the risks involved in any type of surgery. But with the development of femtosecond techniques and intrastromal ablation things are potent to be revolutionized. Moreover it will provide the patients to gofor it since it is safer than before.
Intrastromal ablation is an advancement of lasik eye surgery. It has been brought into application by femtosecond corrections such as Femtosecond Lenticule Extraction, FLIVC, or IntraCOR.
In this technique two opposing focused laser rays are applied, which creates a plasma in tissue (actually it creates a void space in which there are free electrons moving in a partially charged gaseous environment).
This leads to building up of shock waves, that gets transformed into an acoustic transient (i.e. a samll sound is created). The shock wave has a diameter ranging from 0.5μm to a few microns. Thereafter the acoustic transient is very short lived only a few microseconds. It produces a cavity of 10-100μm. Then it collapses to give rise to a small gas chamber (spherical) which contains carbon dioxide and other gases.
This gas bubble when focused on the cornea makes the corneal stroma cells to absorb the gases, which leads to the change of shape of the cornea required to treat the rough cornea problems.
Eye conditions such as astigmatism, presbyopia, myopia, hyperopia finding cure by this. This surgery promises to find a painless and risk free cure. Again as a statutory warning as we give everytime, go for intrastromal ablation after consulting an experienced opthalmologist.
Can this tissue removal be done accurately and predictably enough to facilitate a pre-determined change in corneal shape?
Dr. Luis Ruiz says,
“By means of the femtosecond laser, a customized pattern is applied into the cornea inducing a focal reorganization of the biomechanical fores. In dependence of the applied pattern, the corneal surface can be locally flattened or steepened”.
In his latest phase 3 trial, he has reported that 94% has responded with a highly positive response, while 80% showed almost cured results after a post operative period of six months.
What Dr. Ruiz states may be so, but it still doesn’t answer the question posed above – can this technique result in a controllable, predictable result. We will just have to wait and see if the use of the femtosecond laser can do what others with other laser systems have tried and failed to do in the past.
Source: Irv Aron's Journal