Techniques of cataract removal - Extracapsular cataract extraction (ECCE) involves the removal of almost the entire natural lens while the elastic lens capsule (posterior capsule) is left intact to allow implantation of an intraocular lens. It involves manual expression of the lens through a large (usually ten to twelve mm) incision made in the cornea or sclera. It is very rarely done now a days only indicated for patients with very hard cataracts or other situations in which phacoemulsification is considered to have potential problems.
Disadvantages:
- Long recovery period four to six weeks
- Stitches are required
- Need injection anasthesia
- Higher risk of intraoperative complications
- Higher incidence of postoperative astigmatism with increased dependence on glasses
- Higher chance of posterior capsular opacification and need for laser capsulotomy
Manual small incision cataract surgery (MSICS): This technique is an evolution of ECCE (see below) where the entire lens is expressed out of the eye through a self-sealing scleral tunnel wound (five to six mm) . An appropriately constructed scleral tunnel is watertight and does not require suturing. The "small" in the title refers to the wound being relatively smaller than an ECCE, although it is still markedly larger than a phaco wound. The advantage of this technique is low cost.
Disadvantages:
- Recovery period is about three weeks
- Need injection anasthesia
- Higher postoperative surgical induced astigmatism compare to phacoemulsification
Phacoemulsification – A keyhole incision only two point two to two point eight mm wide is made on the outside of the eye. A circular opening in the lens capsule exposes the cataract. Next the phaco-emulsifier is inserted. This sophisticated instrument uses high-speed ultrasound waves to break the cataract into tiny pieces which are suctioned out of the eye.
Advantages:
- Recovery time is two weeks leading to faster visual rehabilitation
- No injection required – done under topical anasthesia
- Minimal postoperative surgical induced astigmatism