Cataract surgery is a daycase procedure which is normally performed under local anaesthetic to remove a misty natural lens and replace it with an artificial intraocular lens (IOL). The surgery is virtually painless, and there is little postoperative discomfort. Patients can expect to see quite well within 2 days of surgery. The aftercare is simple (just drops 4x per day) and there are few restrictions on activity.
Modern cataract surgery is a form of keyhole surgery in which the natural lens is removed through a 3.5mm valve incision. High frequency ultrasound energy delivered through a probe is used to liquefy the natural lens in a process called phacoemulsification. Lens material is washed out, then a flexible IOL is folded for delivery through the same small incision. Once inside the eye, the IOL unfolds within the lens capsule to lie in the natural position, focussing light accurately on the retina. The small valve incision used in modern cataract surgery is self-sealing, and does not affect the strength of the eye wall.
When the operation is used primarily to reduce spectacle dependence rather than to clear blurred vision resulting from a misty natural lens (i.e a cataract), the operation is referred to as refractive lens exchange (RLE).
As well as the manual incision process, this procedure can be done using a femtosecond laser to make the initial (self-sealing) incisions and to partially breakdown the cataract prior to its aspiration and replacement of the lens.
The IOL options available for cataract/RLE surgery are:
- Single vision lenses – this option gives excellent image quality and allows the patient to either have both eyes set for a uniform focus (near vision or distance vision) or have one eye set for near vision and the other set for distance vision. This is called monovision and is a common method of offering greater spectacle independence than setting both eyes to a
single focus. Toric single vision lenses are available for those who have astigmatism.
- Multifocal lenses – introduced in many varieties over the last 20 years, these IOLs enable patients to have the greatest possible level of spectacle independence because they produce a greater depth of focus than conventional lenses. This is especially true of the newer diffractive IOLs. Toric versions are available for those who have astigmatism. Mr Wilkins has a wealth of experience in multifocal IOL implantation, with excellent results.
Common additional procedures
- Limbal relaxing incisions (LRI) to treat astigmatism
Cataract surgery does not correct astigmatism, but the procedure can be combined with Limbal Relaxing Incisions (LRI), a simple, safe surgical method for reducing astigmatism in which 1 or 2 partial thickness cuts are made in the wall of the eye at 90° to the steeper radius of corneal curvature. These cuts are placed at the edge of the cornea next to the white of the eye (the limbus) and heal quickly, but the shape of the cornea and the amount of astigmatism is changed permanently. LRIs are normally performed in addition to cataract surgery where more than 1.5D of astigmatism is present prior to the procedure. Smaller amounts of astigmatism can be corrected simply by adjusting the position of the wound through which the IOL is implanted.
- YAG capsulotomy to treat Posterior Capsular Opacification (PCO)
In cataract and RLE surgery, the IOL is implanted within the natural lens capsule: a thin diaphanous membrane which encases the natural lens and is often likened to the skin of a grape. In the months after surgery, the lens capsule shrink wraps the IOL and stabilises it definitively in the natural position. Sometimes the lens capsule becomes opacified during this shrink wrapping process, visual quality deteriorates, and it can feel as if the cataract is coming back. The timing of this complication, called posterior capsular opacification (PCO) is variable. But affected patients will typically notice a visual deterioration and problems with light scatter 6 months to 3 years after surgery. This can be corrected by perform a YAG capsulotomy.
Although the visual recovery after cataract surgery is rapid - you can expect to see quite well within 2 days of surgery - we advise a week off work after each procedure. This is not obligatory, and provided you are able to put drops in 4x per day, a return to work on the Monday after surgery will not damage the eyes. Dusty environments are unlikely to damage the eyes, but may be irritating, and should be avoided for 1 week after surgery. Patients who are having refractive lens exchange, or cataract patients who were dependent on distance glasses prior to surgery, will have difficulty obtaining balanced vision in spectacles in the week between having the first and second eye operated on. The alternatives for this stage are wearing a contact lens in the unoperated eye, or leaving one eye relatively blurred (simply removing one spectacle lens creates problems with unequal image size). Once the second eye is operated on, there is normally a swift return of balanced vision, and patients on a tight schedule can usually return to work on the Monday following surgery provided that they are able to continue administering drops 4x per day.
When can I return to normal daily activities?
You can be as active as you like after modern cataract surgery. Bending over and lifting heavy weights are no problem, and flying is permissible from the day after surgery. The main limitations are: no swimming for 1 week after surgery and no eye make up for one week after surgery. Driving is fine once you can read a number plate at 70 feet. If you are in doubt, your vision can be checked on a Monday afternoon following surgery in the second eye to ensure that it is at the driving standard. Driving with good vision in only one eye (between operations) is legal, but you should obviously exercise caution until you feel confident, and drive short distances by day in familiar surroundings before branching out.
Am I suitable?
Suitability for cataract and RLE surgery are mainly determined through the tests performed during your initial consultation. However, you must be 50 or over for you to be offered RLE as an option of sight correction surgery.