Many people wonder if they may need “Laser surgery” after they have had cataract surgery. In fact, many people actually confuse cataract surgery for “Laser surgery.” Actually, modern cataract surgery does not usually involve lasers at all. Instead, a microscopic ultrasound instrument (phacoemulsification probe) is used to break-up and remove a cloudy lens in a patient’s eye. After the cloudy lens is removed, an artificial intraocular lens implant (IOL) is placed within the eye. In the vast majority of cases, however, no laser is involved in this process.
There are a couple of instances where lasers may be some benefit following cataract surgery. The most common is the development of a posterior capsular opacity (PCO) which is a thin, hazy film which can grow across the remnant lens structures behind the IOL. This hazy PCO can partially block the path of light through the IOL and obscure the patient’s vision causing blurred haziness or glare. PCO is actually the most common complication after routine cataract surgery. If it becomes significant enough to limit a patient’s functional vision, then it is generally treated using an instrument called an Nd:YAG laser. This type of laser has been available for several decades and is extremely accurate and successful in clearing a PCO with little to no discomfort and with minimal recovery time. The Nd:YAG laser can be very carefully aimed behind the IOL to cut away an area of the PCO creating a new clear path for light to pass through. The procedure usually takes less than five minutes. From the patient’s perspective it is actually quite easy. The doctor places a plastic “contact lens” onto your eye which holds your eye open and also allows him to focus the laser beam. He then carefully aims the laser so that it cuts a small clear circular area in the PCO. Although there are bright lights involved, the patient typically feels little to nothing. The Nd:YAG procedure has a very high rate of success for restoring vision to a high level.
Another situation that can arise is the occurrence of residual refractive error (glasses prescription) even after cataract surgery with IOL implantation. In the case of a cataract patient, the IOL can be selected to match the characteristics of the eye thus minimizing the patient’s glasses. If there is any residual refractive error, the patient may choose to wear glasses or it may also be possible to use the Excimer laser to correct it. For these cataract surgery patients, there are a number of things to consider.
First, they should understand that the standard IOL cannot change its focus so it is always set to either far or near distance only, but not both. Because of that fact, standard IOL patients require reading glasses if their distance vision is made perfect or they require distance glasses if their up close vision is good. These patients should consider carefully what distances are most important to them in their daily function before undergoing any Lasik vision correction. Also, there are now newer advanced technology IOLs (AT-IOLs) which are able to restore some ability of the eye to focus at different distances. These AT-IOLs are capable of reducing the need for glasses or bifocals to a greater degree than their older standard IOL predecessors. Prior to having cataract surgery, patients should ask their surgeons if they might benefit from the implantation of an AT-IOL.
Second, there are a couple of different ways to use the excimer Laser to correct a refractive error and surgeons have different approaches and philosophies. The two basic methods are called PRK and Lasik. Lasik is the most common vision correction procedure in younger patients that have not had cataract surgery, but many surgeons favor PRK for their cataract surgery patients. I personally prefer Lasik using blade-free Lasik technology. The major difference between PRK and Lasik is the creation of a corneal flap off the front of the eye in Lasik. You can visualize the corneal “flap” as a wall calendar where one page can be flipped up to reveal the underlying page. Similarly, the hinged flap is created on the cornea and lifted up to reveal the underlying corneal tissue. The advantage of Lasik over PRK is the significantly faster healing and visual recovery. Some surgeons prefer the ease of PRK in post-cataract surgery patients because it avoids the need to surgically create the flap. However, the most advanced blade-free Lasik technology can very easily create the flap on post cataract surgery patients. These newer instruments place much less pressure on the eye than the older bladed flap-makers and can cut a corneal flap with far greater precision and accuracy as well. So the quick healing of Lasik can easily be applied to post cataract surgery patients and avoid the slow visual recoveries that can occur in PRK.
Modern cataract surgery is a very highly successful surgery whether laser surgery is required afterward or not and, in fact, the majority of cataract surgery patients never need laser treatment of any kind. Nevertheless, patients should be aware of the possibility that they may benefit in some cases from Nd:YAG or excimer laser (PRK, Lasik). Typically, these lasers will give added visual benefit after cataract surgery but are not absolute necessities. Your surgeon should explain the reasons and potential benefits as well as risks prior to having these additional laser procedures.