Refractive cataract surgery is a relatively new term, used to describe the merging or combination of traditional cataract surgery with modern refractive surgery techniques.
In the past, the goal of cataract surgery was more purelymedical and restorative. The surgery was performed when it was medicallynecessary to remove a cloudy lens in order to restore a person's ability to see(usually with the aid of eyeglasses or contact lenses after surgery).
Most of us must have seen our grandparents using thick unsightly glasses after have undergone cataract surgery. These glasses looked like bigmagnifying glasses. People needed to use these glasses to compensate for theloss of refractive power of the eye, which occurs because if removal of thenatural lens during cataract surgery. It was Harold Ridley who first introducedconcept of intraocular lens to be implanted in the eye instead of using thickglasses postoperatively.
The intraocular lens ( IOL) has been refined and perfected forintraocular use. Currently there are many types of IOLs available. When you approach a surgeon for cataract surgery you will have to make a informed decision with help of your surgeon, as to which IOL you will prefer. Surgeon may have to decide on table for particular design or material for your eye butmostly surgeon will give you alternatives and will like to know yourpreferences.
Factorsthat you should consider in making right choice of IOL
- What is nature of your profession? Do you have an office job or an outdoor job? Do youhave very fine work like graphics, painting or carving?
- What is your lifestyle and hobby? Are you ‘indoor’ person, or do u have interest inoutdoor activities?
- Do you need excellent unaided vision as per need of your profession like pilots,driversetc?
- How important is night vision or vision in dim light for your job?
- Do you have astigmatism or cylindrical glassespower? what is your refractive error-nearsighted of farsighted?
- Would you mind using glasses routinely after surgery or would you rather not?
- And lastbut not least, if you are paying for the cost of surgery from the your pocket,what is your budget? The cost of certain IOLs can be exorbitantly high.
Refractive cataract surgery has a more aggressive goal: Toenable the person who has cataracts to regain good vision and to eliminate or greatly reduce their need for correctiveeyewear, including reading glasses, after surgery.
Types of IOLs
a) Non foldable lens- These are made of Polymethyl meth acrylate. These are low cost and require large incision to be inserted in the eye asthese can not be folded.
b) Foldable IOL- these are made of Acrylic or silicon. These canbe folded so can be inserted through very small incision.once inside the eyethese opne up to full size.
- Monofocal IOL- These are simplest types of foldable IOL available. These give good distant visionbut you have to use reading glasses for near work or reading, These arerelatively low cost and if you don’t mind wearing glasses after surgery you can opt for these lenses.
- MultifocalIOL- These IOL not only give good visionfor distance but give good near vision also. However you may need glasses forreading fine print in telephone directory. Some patient also complain of glarewhile driving in night .So it is not suitable for patient who routinely drive at night. Cost of these IOL is high.
- Accommodative Lens-these lenses are designed in such way that they,like natural lens, can changepower for different distances and hence give good vision without glasses forall distances.These lenses although in use are extremely costly and design hasnot been perfected yet..If you have fad for the latest thing and do not mindthe cost,you may go for it, keeping the possible shortcomings.
- Toric intraocular lens- Toric IOLs correct astigmatism orcylindrical power. Residual astigmatism is a primary reason why people stillneed to wear eyeglasses after conventional cataract surgery.these IOL may needreadjustments and are quite costly.
- Aspheric IOL – These lenses have a design such as used in cameras and telescopes which increases the quality if vision by removing orreducing the optical aberrations. These give better contrast sensitivity particularly at night time .these cost marginally more that routine IOL and is good for artists,drivers,pilots etc.
Laser Cataract Surgery
Considerable research is underway to study the use of lasertechnology to perform the cataract surgery procedure. Research studies suggest that laser cataract surgery may provide an additional measure of stability and accuracy,and thus has the potential to improve the visual outcome and reduce recovery time for refractive cataract surgery.
Corneal Refractive Surgery after Cataract Surgery
In addition to premium IOLs, refractive cataract surgery may involve the use of LASIK surgery,PRK, Conductive keratoplasty (CK) or other corneal refractive procedures after cataractsurgery to provide greater independence from eyeglasses.
If some nearsightedness, farsightedness or astigmatism remainsafter cataract procedures, one of these refractive procedures performed on thecornea can improve uncorrected visual acuity. For the correction of presbyopia after cataract surgery with conventional (monofocal) IOLs, a procedure such as PresbyLASIK is oneway to reduce the need for reading glasses.