How to Choose the Best Operation for You

There are over 3 million cataract surgeries performed in the United States a year. As discussed previously, you first need to have a thorough eye exam. Maybe, you only need a new glass prescription to correct your vision. There is almost never a need for cataract surgery except in rare circumstances. You only need to consider cataract surgery when your vision is blurred to the point that you are unhappy with your vision. It is never because some eye doctor says that is time for your cataract surgery or that you need cataract surgery. The choice is always yours. If you have decided that you need to see better, what are the next steps?

What is Your Goal or Desired Outcome with Cataract Surgery?

What are the goals that you have from having your cataracts removed? Do you just want to see better? You have always hated wearing glasses and would like to reduce or eliminate wearing glasses after surgery? Is seeing well at distance without glasses and only wearing reading glasses for near a goal? Or, you hate glasses and don’t want to wear glasses for distance or reading? There are many options related with cataract surgery.

Femto Laser Cataract Surgery

We are pleased to offer our patients the LenSx Femto-Laser. Our surgery center was of the first office’s in the Untied States to have a LenSx laser. Many eye surgeons advertise this as bladeless laser cataract surgery. There are many eye surgeons who have turned off the incision making portion of the femto laser even though they advertise it as bladeless. The femto laser is a laser that performs several of the steps during cataract surgery. Many people believe that the laser magically removes the cataract but the laser does not actually remove the cataract. The femto laser can make the small incisions in the cornea that are used during the cataract surgery. The femto laser performs the very delicate anterior capsulorhexis in the anterior capsule of the lens in a very precise size and shape. Since the laser is so precise, the post op vision results are better and more consistent due to effective lens plane. Effective plane means that the IOL will be more consistently located in the same location or plane from case to case. The femto laser makes cuts in the nucleus of the lens, and the laser can use a pattern of laser cuts to soften the nucleus for easier removal. One of the most important benefits of the femto laser is that it makes limbal relaxing incisions or performs astigmatic keratotomies in the cornea to correct the astigmatism of the eye. With astigmatism, the cornea is shaped like a football that is cut length-wise versus an eye without astigmatism that is round like a basketball. If your eye has between 0.5 diopters to 1.25 diopters of astigmatism, the femto laser is a fabulous way of correcting this amount of astigmatism which will provide better vision without glasses. The femto laser can also be used to place small marks on the cornea align a toric or astigmatism intraocular lens. You should discuss whether the femto laser is good option with your eye surgeon.

Intraocular Lens Options for Cataract Surgery

There are 4 basic types of intraocular lenses, IOLs, or implants.

Monocular IOLs

A monocular lens has one specific strength or power to correct vision. There are two types of monocular lenses which have a single power of focus which are traditional monocular lenses and aspheric monocular lenses. Some eye surgeons refer to aspheric IOLs as high definition monocular lenses.

Multifocal IOLs

Multifocal lenses have a bifocal-like way of providing vision at distance and near. There are two types of multifocal lenses which are diffractive lenses and extended-depth of focus lenses. Diffractive IOLs form 2 separate images in the eye with one at distance and one at near. When you look at distance, the only image the eye can see is the distance image and when you look at near, the only image that the eye can see is the near image. Extended-depth-of-focus lenses (EDOF) provide distance and near vision by expanding the range or depth of focus of the lens.

Vision Option 1

One option is to have traditional cataract surgery with a monofocal IOL. The goal is to see well at a distance if your eye does not have significant astigmatism and you will most likely need reading glasses for up-close vision.

Traditional Monofocal Spherical IOLs

Traditional monofocal spherical IOLs have been available for over 40 years and provide very good vision after cataract surgery. Over the years the designs have been dramatically improved. They are round or spherical in shape just like a magnifying lens. Monofocal lenses have one power or strength designed to focus objects in one location or distance. These types of IOLs are covered by Medicare and insurance companies.

Lenstec IOL
Intraocular Lense

Vision Option 2

Aspheric or High Definition Monofocal IOLs

Up until recently, all lenses for eyeglasses and IOLs were spherical or round like a basketball. The shape of the cornea which is a major refractive component of the vision system is not round. It is aspheric in shape as the cornea is steeper in the central cornea and flatter in the peripheral cornea. A spherical lens does not bend or focus light in the same manner as the cornea or eye. Traditional round or spherical lenses can cause high order aberrations in our vision. This can have an effect on the overall quality of the vision especially in low light. Part of the pre-op testing includes measurements of sphericity and aberrations of the eye. An aspheric IOL which better matches the eye can be used to provide sharper vision with better contrast, and less problems with night vision. The best example would be the difference between a regular TV and a high definition TV. These aspheric IOLs can be used to focus your eyes for distance, intermediate, and near vision. Some of the more common aspheric IOLs are Alcon (AcrySof IQ), Lenstec (Softec HD), Abbott Medical Optics (Tecnis Aspheric), and Bausch and Lomb (SofPost AO).

Vision Option 3

Monovision surgery with monofocal IOLs where the dominant eye is focused at distance and the non-dominant eye focused at near with the IOLS. The best candidate for monovision is someone who has worn contact lenses with monovision correction. Many people feel disoriented wearing monovision contacts and cataract surgery in this manner is permanent. If you are interested in monovision and have never tried monovision, you should try wearing contact lenses with monovision for a period of time before deciding to have your cataract surgery in this manner.

Vision Option 4

There is a modified-monovision option with monofocal IOLs where the dominant eye focused at distance and the non-dominant eye is focused minimally at near. A slight amount of monovision will most likely not cause any of the problems associated with regular monovision which are disorientation, dizziness, unstable feeling, and loss of depth perception. With this modified monovision correction, people are usually able to see prices at the grocery store, read a menu in a restaurant, and perform their daily routine activities without wearing glasses. There are some people who are able to read a book without glasses but looking at any fine print will require reading glasses.

Vision Option 5

Toric Monofocal IOLs (Astigmatism Correcting IOLs)

This type of IOL is a great choice for people with astigmatism. Toric IOLs are used to correct astigmatism from 1.25 diopters or more of astigmatism from the shape of the eye. Astigmatism means that the cornea is shaped like a football cut length-wise which is more curved in one direction verses the other. An eye without astigmatism is round basketball cut in half. The light that goes through a cornea with astigmatism is focused to a line on the retina. That is why people with astigmatism see streaks around lights at night or ghost images without their glasses on. The light that is focused through a cornea is round is focused to a sharp point on the retina.

Alcon Toric IOL with Three Small Marks on Lens for Alignment
Intraocular Lense

A toric IOL is designed so that it corrects the astigmatism just like glasses correct astigmatism. The IOL is stronger or has higher power in one axis or meridian and is weaker or has less power 90 degrees in the opposite axis or meridian. Indicator marks are placed on the IOL to show the axis or direction of the astigmatism so they the IOL can be aligned to the astigmatism of the eye. Prior to surgery, marks are placed on the eye to provides reference points to the axis of the astigmatism or an image of the eye can be taken to show the axis of the astigmatism. During the surgery, the toric IOL is placed inside the eye and aligned with the astigmatism of the eye. Common toric IOLs are Alcon (AcrySof IQ Toric), Star Toric IOL, and Bausch and Lomb (Trulign Toric).

Vision Option 6

Multifocal IOLs

This option is for people who hate wearing glasses and wish to have surgery that will eliminate or drastically reduce their dependence on glasses. Presbyopic IOLs are designed to give distance and near vision through the intraocular lens. They work similar to bifocal glasses but have a completely different technology. There are multifocal IOLs, accommodating IOLs and extended-depth-of-focus IOLs.

How Do Multifocal Lenses Work?

Multifocal IOLs are designed to provide vision at distance and near. These are also known as bifocal IOLs. The IOLs are designed to split the light coming into the eye and going through the IOLs into two images. There is one image for distance and one image is focused at near. The IOLs are designed with diffractive ridges, edges, or steps on the surface of the lens in a circular pattern. The light is separated as it goes through these ridges which results in two separate images. This is a different technology from a bifocal lens in glasses where there two different strengths of lenses and you have to look down through the bifocal to see up close. You can’t look down into the bifocal portion of the IOL as it fixed inside the eye. The multifocal IOL produces two separate images for distance and near. When you look at distance, the only image that the eye can see is the distance image. When you look up close, the only image that the eye can see is the near image. It does not matter whether you are looking up, down, or to the side. The image your eye can see is based on distance from the eye.

Alcon Multifocal IOL
Intraocular Lense

Testing Prior to Surgery is Paramount with These IOLs

For presbyopic IOLs, one of the most important steps prior to your cataract surgery is thorough testing of your eyes. The tests provide your eye surgeon valuable information essential in guiding you in choosing the best type of IOL based on how you wish to see after the cataract surgery. For multifocal IOLs, you need to have a completely normal eye and vision system. The correct power of lens needs to be chosen. Everything needs to be right for a good result. Multifocal lenses are not for everyone. It is much better to make the proper choice of the type of surgery and IOL before your cataract surgery than have the wrong type of IOL placed in the eye. The surgery to remove an IOL and replace the IOL can be much more difficult than the initial surgery. You are putting your eye through another operation with its risks and complications. Be wise and make the proper choice for you and not some type of surgery the eye surgeon is pushing you to do. A second opinion is always a good idea.

Are You a Good Candidate for a Multifocal IOL?

  • You need to have a completely healthy eye
  • No significant dry eye disease
  • Normal cornea and especially no Fuchs dystrophy
  • No macular degeneration
  • Very little aberrations in your visual system
  • The visual axis and the center of the pupil need to be very close to the same (small angle kappa)
  • Astigmatism is minimal or the astigmatism is correctable with femto laser or toric multifocal IOL

Multifocal IOL Pros and Cons


  • For people who are good candidates, the IOLs provide very good distance and near vision
  • Multifocal IOLs are the best IOL for total relief from wearing glasses


  • Decreased contrast sensitivity
  • You will see halos or rings around lights at night. In good candidates, this diminishes over time.
  • You need good light to read
  • There is a brain process called neural adaptation which helps you learn how to see with these IOLs. The brain is able to adjust to the new way that light is being focused in your eyes. Over time, neural adaptation minimizes the rings, halos, and contrast sensitivity issues. If prior testing shows that you are a good candidate for multifocal IOLs, you can have an excellent result. Companies that make these types of IOLs are Alcon (AcrySof IQ ReStor) and Abbott Medical Optics (Tecnis Multifocal).

Accommodating Monofocal IOLs

Accommodating IOLs are designed to focus moving inside the eye when you look at near or up close. The accommodating IOL moves forward inside the eye as you focus up close as the focusing muscles inside the eye contract. The forward motion increases the effective power of the IOL to help you see at near. Just like moving a magnifying lens closer or further away from an object changes the focus of the magnifying lens. The lens is designed with flexible haptics or appendages attached to the IOL which allows the IOL to move inside the eye. This IOL design has some limitations in that this movement can be minimal in some cases limiting the amount of clear near vision and the amount of movement may reduce over time. Accommodation IOLs are Bausch and Lomb (Crystalens AO and Trulign Toric).

The Lenstar and IOL master are the two most common instruments used to measure the eye for determining the power of the intraocular lens that is going to be used to correct your vision during the surgery. These instruments take a variety of measurements of the eye and a computer in the instrument determines the strength of the lens that is going to correct your vision. These instruments are very accurate but not perfect. There is no guarantee that the instrument will be perfect in your particular case.

Once the eye surgeon has the information they need to help you with the decision-making process on the variety of options you have with your cataract surgery, you will make the decision on the type of surgery you are going to have performed on your eye and the type of intraocular lens that will be inserted into the eye.

A surgical coordinator or staff member will go over all the details of having cataract surgery. There will be numerous forms and papers that you will need to sign. You will read over the informed consent for having cataract surgery which the surgeon will go over. In most cases, you will be using eye drop medications before and after the surgery. The staff will go over the pre-op and post-op instructions and give you a written copy for you to follow.

Extended Depth of Focus IOLs (EDOF IOLs)

An extended range of focus or extended depth of focus is a new IOL design. This multifocal-like lens does not split the light into two separate images like the other multifocal IOLs but provides near vision by extending the depth of focus which allows for near vision. The advantage of this IOL is that it does not reduce contrast sensitivity and form rings or halos around lights like regular multifocal IOLs. Another benefit is that is does not reduce reading vision in low levels of light as do multifocal IOLs. This type of IOL typically does not provide as good as reading vision as true multifocal IOLs but does allow people to see reasonable size print, restaurant menus, and prices at the grocery store. For looking at very fine print, you may need a weak reading glass. The extended-depth-of-focus IOL is made by Abbott Medical Optics (Symfony IOL).

Extended Depth of Focus IOLs (EDOF IOLs)

Astigmatism or Toric Multifocal IOLs

If your goal is to not wear glasses and you have astigmatism, there are now options. If you who have 1 to 1.25 diopters of astigmatism or less, you can have the LenSx Femto Laser correct your astigmatism along with having a multifocal IOL to correct your vision.

If you have greater than 1.25 diopters of astigmatism, then there are two multifocal or extended depth of focus IOLs available that will give you distance and near vision. These are the multifocal Alcon (AcrySof ReStor Multifocal Toric IOL) and the extended depth of focus Abbott Medical Optics (Tecnis Symfony Toric IOL). There is also the accommodating toric IOL made by Bausch and Lomb (Trulign Toric IOL0.)

Symfony Toric IOL with Three Alignment Marks
Symfony Toric IOL with Three Alignment Marks

Different IOLs in Each Eye

There may be a case where you only have astigmatism in one eye or different amounts of astigmatism in each eye. You are not limited to the same IOL in both eyes. You can choose to have different types of surgery in each eye or different types of IOLs in each eye to maximize your vision and decrease the need for wearing glasses after surgery. Your eye surgeon will go over the different options that you may have based on the health of your eye and your goals of how to see after the surgery.


As you can see, there are very many options for cataract surgery. Traditional monofocal IOL are covered by Medicare and insurance companies. The other types of IOLs discussed are not covered by Medicare or insurance companies. These IOLs are designed to decrease your need of wearing glasses and are not covered as Medicare and insurance companies do not consider it medically necessary to decrease your need of wearing glasses. These new IOLs are designed to correct your vision such as for astigmatism or reading vision. Since you are choosing to have a newer technology IOL that is designed to decrease or eliminate the need for glasses, these are not covered. Medicare and insurance companies do not believe that they need to correct your vision. They only pay for routine surgery with monocular IOLs.

Once you have decided for yourself that you are unhappy with your vision and need to see better, the next question is how do you want to see after cataract surgery. You are OK with wearing glasses after surgery or you want to decrease your need for wearing glasses.

The next step is to find the right eye surgeon for you. As indicated in the beginning, there are many eye surgeons who only care about doing as many surgeries as possible. Many of them will try to tell you that it is necessary for you to have surgery right away. Many eye doctors offices will also push you toward the more expensive new technologies even if you are not the best candidate for that type of IOL. How do you know what to do? You can ask your family physician for recommendation or ask who do they go to. Other thing that you can do is to make sure that your eye surgeon is board certified, is a member of their state ophthalmology society, local societies, and have a clean record.

You need thorough eye testing of your eyes to help you determine the best procedure and IOL for your specific needs and goals. Your eye surgeon should be your guide and help you make the best decision. If the eye surgeon is pushing you into surgery or a specific type of surgery or IOL, then get a second opinion.

The Cataract & Refractive
Institute of Florida

James E. Croley III, M.D.

Office Hours

  • Monday

    7:30am – 4:00pm
    Dr. Croley sees patients at 7:30am in Cape Coral.

  • Tuesday

    8:00am – 4:00pm
    Dr. Croley performs surgeries on this day.

  • Wednesday

    7:30am – 4:00pm
    Dr. Croley sees patients at 7:30am in Cape Coral.

  • Thursday

    8:00am – 3:30pm
    Dr. Croley sees patients at 8:30am in Lehigh.

  • Friday

    8:00am – 3:30pm
    Dr. Croley alternates also in Bonita & Cape Coral.

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