Cataract is a condition in which the natural lens of the eye becomes dense and cloudy, impairing
vision as a result. This happens when the protein in the lens begin to clump together. Cataract
affects people over the age of 40 and more than half of the American population over the age of
70 have cataract. Cataract surgery involves the removal of the clumped fibers and implanting an intraocular lens
within the lens membrane to improve vision.
Capsular staining to avoid complications
In cases where cataract has advanced, surgeons sometimes use a technique called capsulorhexis to remove the lens capsule, a thin membrane that stretches to give the eye it's round and globular shape. In most cases, capsulorhexis refers to the removal of a part or whole of the anterior portion of the lens capsule. The use of Laser Cataract surgery has helped reduce the need for this stain. The laser can create the capsulorhexis without a red reflex.
An important aspect that determines the success of a capsulorhexis is the red reflex. There exists a reddish-orange reflection of light from the back of the eye. This is usually tested using an ophthalmoscope. A poor red reflex indicates the presence of abnormalities such as cataract. During the surgery, a poor red reflex leads to poor capsulorhexis due to the poor structure of the anterior capsule. In such cases, a badly performed procedure can result in complications such as edema, scarring, hemorrhage, and retinal disease.
Capsular staining is a process in which a dye is used to visualize the damaged fibers. This in turn aids in the proper removal of such fibers without having any adverse effect. The most commonly used dye is Trypan blue. The dye colors dead tissues and cells blue and does not have any impact on properly functioning cells.
Application of the dye
The dye is applied using either one of two techniques. One technique involves injecting the dye into the anterior portion of the capsule using an air bubble. The other technique involves
injection of the eye using a viscoelastic, or a material that exhibits both elastic and viscous properties. In both methods, the recovery time, complications, and post-operative vision remained almost same. Very slight differences exist in terms of complexity of the procedure and cost. Injection using an air bubble is an economical procedure. The post-operative trauma however, is slightly higher in case of this procedure. Injection using a viscoelastic material is a more expensive procedure, but has advantages in terms of less post-operative trauma. The method of using an air bubble is relatively unstable according to doctors.