This technique is used to treat retinal detachment. It is called episcleral because it is performed on the sclera, the external white layer of the eye.
With the episcleral technique, the tear caused by retinal detachment is sealed by bringing the wall of the eye and the tear close together to seal it. In order to do this, the surgeon performs a technique called sealing, meaning that s/he positions a small silicone sponge on the sclera to close the tear.
Cerclage or Buckling
To reduce the traction the vitreous exerts on the retina, and consequently on its tear, the surgeon can add a silicone band that will tighten like a belt around the equator of the eye. This silicone band is used in a technique called Cerclage or Buckling; it reduces the diameter of the eye and decreases the traction forces exerted on the retina by the detached vitreous.
In some cases, simply closing the tear may be sufficient to treat retinal detachment. The liquid below the retina is normally re-absorbed by the eye itself and consequently, the surgeon may not have to remove it manually.
Advantages and disadvantages
An eye treated with the sealing or buckling techniques may subsequently develop sight defects: this means that a myopic eye may become more myopic, and an emmetropic eye (that is, an eye that does not require spectacles for distance vision) may become myopic.
The advantages of this technique are that it is fairly rapid and is not particularly invasive because it is performed on the outside of the eye.