Cataract Surgery - What to Expect (post 2 of 3) - Day of Surgery

Continuing my series of posts covering what to expect around the time of cataract surgery: today I will describe what I tell my patients to expect the day of surgery. Remember, this is what I tell my patients to expect - other surgeons will differ in what they tell their patients to expect depending on technique and preferences.

Day of Surgery:

1) When you arrive at the surgery center there will be some minimal additional paperwork to fill out.

2) You will change out of your clothing into a hospital gown (note: some surgery centers do not require this).

3) A mark will be made on your forehead indicating which eye is to have cataract surgery. This may be done in the "pre-op" area or in the operating room depending on which surgery center is used.

4) During the time you are in the surgery center you may be asked multiple times “what eye are you having surgery on?” This is not because the staff don’t know but because they check and double check that we are operating on the correct eye. This is for your protection.

5) Multiple drops will be placed in your eye multiple times. Although the drops you use at home must be spaced at least five minutes apart, the drops in the hospital will be given to you one right after the other. This is OK.

6) It may take 45 minutes to two hours for your eye to dilate enough to safely perform surgery. The doctor will check your pupil once you are in the operating room. Do not worry about the dilation - if needed there are techniques your doctor can use during surgery to sufficiently dilate your pupil.

7) An IV will be placed in your arm either in the pre-operative holding area or in the operating room. Once in the operating room the anesthesiologist will give you something through the IV to relax you. One of the effects of this medication is short-term amnesia. So, if you are having your second eye done, don’t be surprised if you don’t remember all of these things being done when you had your first cataract surgery. This is a very common feeling.

8 ) A blood pressure cuff will be placed on your other arm. This is necessary for monitoring this critical vital sign. Periodically this will inflate and give you a sense of pressure. Just relax and the pressure will go away.

9) Some doctors (myself included) feel that music works both to relax you and assist with the rhythm of surgery. If you have a particular type of music you would like to be played during the surgery, let your surgeon know. Note: not all surgeons accept requests, but I do (my iPod has over 9,000 songs so I can honor almost any request except country music - closest I have on my iPod is Johnny Cash, but I'll even listen to country music if you bring the CD).

10) During the actual surgery you will hear buzzing and bells. There may be a sense of pressure in the eye and you may feel fluid running down the side of your face. This is all normal.

11) You should not feel pain during the surgery (but you will feel pressure and sometimes a sense of "tugging"). If you do feel pain or discomfort, let your surgeon know and he will give you additional anesthetic.

12) You will be in the operating room for about 45 minutes to an hour. About half of this time is spent preparing for the actual surgery.

13) After surgery a shield will be placed over your surgery eye. you will then be transferred to a recovery area for and hour or so while the nurses check your vitals and confirm that you have recovered from the anesthetic.

14) The entire process from the time you arrive to the time you leave the hospital can take from three to five hours.

Afternoon and Evening of surgery:

You may have the sense that there is something in your eye like a grain of sand. This is normal and will be relieved by using the drops that you have been instructed to use. If needed, you may take Tylenol for relief. You should not have significant pain. If you do, call your surgeon's office as soon as possible.

Note: find out who will be taking call for your surgeon. Will it be the surgeon or another ophthalmologist or optometrist? Will you be able to get through 24 hours a day, seven days a week? Or, will you be forced to go to the emergency room after hours if there is a problem? Practices vary, but I take my own call except for every third weekend when my partner, Dr. Richard Kratz, takes call for me. Even then, he can get in touch with me as I carry my cell phone everywhere I go (I will even give my personal cell phone number to my patients who have had cataract surgery - though the fastest way to get in touch with me is actually through my answering service which picks up the phone whenever my office is closed - no answering machine or voicemail here).

Next post: what to expect after surgery...

© 2009 David Richardson, MD

Cataract Surgery - What to Expect (post 1 of 3) - Before Surgery

Over the course of this blog I will try to address all of the common questions I get asked by my patients. Many of these questions have to do with expectations. The next few posts will be about the mundane activities that surround cataract surgery: the stuff you can do, the stuff you should do, and the stuff you should not do.

Note: these posts will reflect my personal preferences. Other surgeons will have their own set of expectations. Each surgeon creates a set of guidelines based on his or her experience, training, techniques, and understanding of the literature. Additionally, I will modify these guidelines based on the needs or health of an individual patient.

So, assuming you have already chosen a surgeon and he or she has confirmed that you have a cataract and you would benefit from cataract surgery, what can you expect Prior to Cataract Surgery?

If you are a contact lens wearer you will need to stop wearing the lens in the eye that will have surgery for at least three weeks prior to surgery. You may need to return to the office multiple times to have your corneal curvature measured prior to surgery.

You will need to coordinate pre-operative medical clearance from your internist or family physician. This may include blood testing, an EKG, and a physical exam. This should be done at least two weeks (but not more than a month) prior to surgery.

You will need to come into the office for additional testing of the eye and to complete the necessary paperwork prior to surgery. Please make sure to bring your consent and filled out questionnaire with you. Expect to be in our office for two to three hours.

Expect a call from us about two to three days prior to surgery to let you know what time you need to arrive at the surgery center.

You will be using drops in the eye that will be operated on beginning three or four days prior to surgery. These drops function to protect the eye from infection and inflammation. We may have samples of some of the drops, but you will have to go to the pharmacy to pick up the others.

You can eat the night before surgery. After midnight, however, you should not eat or drink anything.

Next post: What to Expect the Day of Surgery

© 2009 David Richardson, MD

Why Cataract Surgery Might Not Be a "Piece of Cake" with Diabetes

While it is true that for most people cataract surgery is a "piece of cake," for surgery to go well it helps to have an otherwise healthy eye. If someone has any eye disease in addition to the cataract this will increase the risk that the final vision will be limited after surgery.

Unfortunately, the general experience of most people who have had cataract surgery does not apply when there is a history of diabetic retinopathy. People with otherwise healthy eyes might note that their vision was better before they even left the operating room. However, most of these people do not have diabetic retinopathy (for more on diabetic retinopathy visit my practice website and search for "diabetic retinopathy" - a list of articles and educational animations will be visible).

A history of diabetic retinopathy increases the risk of surgery. Eyes with a history of retinopathy are at higher risk of macular edema (swelling of the retina), and infection. Treating these conditions can be challenging.

Additionally, decreased night vision is often a result of the laser treatment for proliferative retinopathy (that's still better than the alternative of no treatment - loss of central and overall vision). Cataract surgery may help by allowing more light into the eye, but it will not completely improve it - there will still be some permanent limitation of night vision.

The most important thing someone with Diabetes can do to limit these additional risks of cataract surgery is to maintain good control of the blood sugar.

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 9 of 9)

All right. Here we are. The final installment. All that's left now is to 'close' and double-check:

The incisions were then hydrated...

One method of closing the incision is to hydrate' it. Essentially, a sterile salt solution is injected into the cornea. This results in a local swelling around the incision forcing the incision closed. Often this acts as a substitute for suturing the incision. The problem is that we really don't know how long this swelling lasts. Will it keep the incision closed long enough to protect the eye from infection? For this reason I will often add a suture (see last post).

...and the anterior chamber was formed to physiologic pressure (confirmed by intraoperative tonometry) at which pressure the incisions were checked and felt to be watertight and of good integrity.

Basically, sterile saline is injected into the eye through the paracentesis (small 1mm incision) to bring the pressure in the eye back up to a 'normal' pressure. The incisions are then checked for leaks.

The lid speculum and drapes were then removed followed by placement of Vigamox drops in the fornices on the left.

Remember the bent-paperclip-like device used to keep the eye open? We don't need that anymore as the surgery is over. As a final step to protect from infection a drop of antibiotic is placed on the surface of the eye. Some surgeons inject an antibiotic into the eye at the end of surgery. To date there is no agreement in the US as to which provides more protection. There is a recently published European study that supports using an injection. However, the antibiotic used in the European study is not readily available for intraocular use in the USA. Therefore, most North American surgeons feel the risks of using a 'compounded' antibiotic (made by hand) out weights the potential protection it might provide. As mentioned in my last post, I have not had an episode of acute endophthalmitis in over 2,000 cases of cataract surgery using topical, not intraocular antibiotics. As this rate is similar to that experienced with the European method there does not seem to be a convincing reason to change. Again, using the wisdom of my father, 'If it's not broke, don't fix it.'

A shield was then placed over the left eye which the patient was instructed to keep on the eye except during placement of Nevanac, Vigamox, Omnipred 1% drops which she is to use including the day of surgery.

With topical anesthetic there is no need to patch the eye. A shield with little holes in it is sufficient to protect the eye from rubbing when the patient is sleeping. Additionally a shield is easier to take on and off than a patch. This is important in order to get the antibiotic and anti-inflammatory protection of the prescription drops.

She was instructed to avoid any heavy exertion...

Basically, I tell my patients not to pick up anything over 20 pounds, avoid swimming, gardening, high-impact aerobic activities, and "jerking" activities such as roller coaster riding, bungee jumping, skydiving, and the like. Most standard daily activities are just fine.

...and is to follow up in my office the day after surgery.

It is also acceptable to follow-up the day of surgery.

She tolerated the procedure well.

This is an understatement. Most people find cataract surgery to be a painless procedure and look forward to having surgery on their second eye shortly after their first eye has healed from surgery.

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 8 of 9)

We're almost done. Believe it or not, however, these last steps can take up almost a third of the total time of surgery:

A single 10-0 Vicryl suture was then placed in the temporal corneal incision and the knot was buried in the corneal stroma.

These sutures are incredibly thin (about as thick as a strand of blond baby hair), difficult to work with (ever tried tying a knot of thin hair?), and expensive (about $15 per suture). Thus, suturing the incision is skipped by many surgeons.

No doubt you've seen advertisements for 'no-stitch' cataract surgery. It's sexy not to place a suture. And, it probably isn't necessary every time. If I am convinced beyond a doubt that the incision is watertight without the need for a suture then I won't place one either.

There are many reasons given for not placing a suture as it (1) may result in irritation; (2) can result in surface bleeding aka a 'sub-conjunctival hemorrhage;' (3) might have to be removed in the office. Certainly no surgeon wants his or her patients to have a beet-red eye after surgery because a suture was placed. And, a sub-conjunctival hemorrhage can look awful: 'what happened to your eye!' is another phrase surgeons don't want their patients to hear (it makes for bad advertising).

Additionally, as mentioned above, suturing is time consuming and expensive. Placing a suture can add five minutes to the time of surgery. This may not sound like much, but consider this: my average cataract surgery without placing a suture lasts 12-14 minutes. By placing a suture I have just increased my surgery time by almost 40%. Believe it or not, with the downward pressure on cataract surgery reimbursement (it is now about 1/10th of what it was in the 1970s) the only way for a surgeon and surgery center to make ends meet is to be efficient.

I like performing surgery and insurance companies know that most cataract surgeons would do this as a hobby. Thus, as long as I am not losing money on my surgery I'll keep doing it. And, as long as my surgery center allows, I'll keep placing a suture when I think it is needed. Why? Because placing a suture may decrease the risk of infection. I mentioned earlier that infection is one of the few things that can result in a loss of vision (or even blindness). If I can reduce the risk of infection from 1 in 500 to 1 in 1,000 or 2,000 then I will.

To date I have performed over 2,000 cataract surgeries without a single case of acute endophthalmitis (early infection of the eye). Most published studies on endophthalmitis report rates of 1 in 500 to 1 in 1,000. I believe part of the reason my patients have avoided this complication is my meticulous attention to incision closure and use of a suture when I feel it would benefit the integrity of the incision.

One more post to go...

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 7 of 9)

Continuing my series on what happens during cataract surgery, we have so far removed the cataract, but still have to place the new lens in the eye.

Provisc was then injected into the anterior chamber and capsular bag...

After phacoemulsification of the cataract and aspiration of the cortex, there is little remaining viscoelastic. In order to safely place the new intraocular lens (IOL) in the eye this gel must be replaced. This step also functions to open up the capsular bag and make it easier to position the IOL inside the bag. As much as possible we try to leave things as they were. What better place for the new lens than where the old lens (cataract) was: in the bag?

...following which the lens was inspected for proper power and good integrity.

I personally check the model and strength of the IOL before surgery and just before implantation in the eye. Although not all surgeons personally do this, I feel that this is something I should not delegate to someone else. Which IOL is placed in the eye determines the final vision after surgery. Pretty important step, wouldn't you agree?

The lens was placed in the insertion device which was used to insert the lens through the temporal incision,...

Not all lenses have to be placed in the eye using an inserter. Most lenses can also be folded. However, something must be done to the IOL in order to get it through the incision. Remember that the incision is only 2.2-3.6mm wide. Most IOLs have optics (round lenses) that are 5.5-6.0mm in diameter. Thus, they must be rolled, folded, or otherwise deformed in order to fit them through the corneal incision. Because they must be flexible, most modern IOLs are made of malleable materials such as silicon or acrylic.

...guiding the leading haptic into the capsular bag. The trailing haptic was positioned in the capsular bag using a lens manipulator.

The 'haptics' are flexible loops that stick out from the optic. These act to hold the lens in place and center it in the bag.

The remaining viscoelastic was then removed using automated irrigation and aspiration, taking care that no residual viscoelastic was trapped behind the optic.

Now that the cataract has been removed and the new lens is in the eye it is time to remove the protective gel. If it is left in the eye it will clog up the drainage system resulting in a high intraocular pressure after surgery. Many times, even with diligent removal of the viscoelastic material the pressure will still 'spike' up in the first 24 hours after surgery. However, this is often easily controlled with drops or by letting some of the fluid out of the eye through the paracentesis created at the beginning of the surgery.

Because the more advanced viscoelastics (which are thought to be more corneal protective) are more likely to remain in the eye after surgery I will go 'behind the lens' in order to remove as much as I can. Many surgeons choose not to take this extra step because it is risky without proper technique and difficult to do without a bi-manual irrigation and aspiration setup.

We are almost done. Next post: placing the suture.

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 6 of 9)

Finally, it is time to remove the cataract:

Hydrodissection and hydrodelineation were then completed with a visible fluid wave and good nuclear mobility noted.

'Hydrodissection' is a technique used to free the cataract from its attachments to the capsular bag. Without freeing the lens, all surgical forces that act on the lens would be translated through the capsule to the zonules (the delicate cables that hold the lens in place). If these zonules are damaged during surgery then there will not be sufficient support to place a clear new lens in the eye.

During hydrodissection fluid is injected between the capsule and lens. This fluid travels around the lens creating a space between it and the capsule. If this step is not completed the remaining steps of catarct removal are more difficult and dangerous to perform.

Hydrodelineation is very similar to hydrodissetion except the layers separated are those of the lens nucleus (hard, central part of the cataract) and epi-nucleus (softer outer part of the cataract). This step does not have to be performed unless the surgeon uses an advanced technique call 'phaco-chop' (more on that next).

Phacoemulsification of the nucleus was then completed using a horizontal chop phacoemulsification technique requiring 0.6 minutes of phacoemulsification at 24% power.

Phacoemulsification is the ultrasound technology currently used by the majority of US surgeons. Essentially, a hollow tip vibrates at an extremely high frequency (faster than the speed of sound) breaking up the cataract into small pieces. These fragments are then vacuumed through the central opening of the tip and out of the eye. Other methods of breaking up the cataract do exist including laser and pulses of water. However, neither of these has really caught on in the US as the ultrasound works so well for most types of cataracts.

There is, however, a downside to ultrasound. If the tip of the ultrasound handpiece touches the capsule, the bag will tear allowing vitreous (the gel behind the capsular bag) to come forward. This is the main thing all cataract surgeons try to avoid as it often significantly complicates the surgery. Additionally, as discussed earlier, the ultrasound energy is not only absorbed by the cataract, but also by the cornea resulting in swelling. An advanced technique such as phaco-chop can reduce the total amount of ultrasound time used (compared to older and more basic techniques such as 'divide and conquer') and thus limit the amount of corneal edema.

The remaining cortex was then removed using bimanual automated irrigation and aspiration.

The cortex is that part of the catarct still adherent to the capsular bag. It has a stringy, tenacious character to it and is usually still present even with hydrodissection. It must be removed or the bag will not be optically clear resulting in blurred vision and inflammation. However, the capsule is very delicate an tears with any significant traction on it. To get an idea of what this is like lay out some cheap plastic wrap (the stuff you use to cover leftovers before you put them in the refrigerator) and stick some painter's tape on it. Now try to remove the tape without stretching or tearing the plastic wrap.

As you can imagine, this is another step in cataract surgery which has a high risk of 'capsular rupture,' resulting in 'vitreous loss,' or tearing of the capsule allowing the vitreous gel to come forward.

In order to decrease this risk I use a technique called 'bi-manual' irrigation and aspiration. This requires the simultaneous use of two instruments (rather than one) allowing me to obtain better control in the eye. Not every surgeon, however, uses the bi-manual technique as it requires (1) expensive handpieces that many surgery centers will not pay for (I own my bi-manual handpieces); (2) phacoemulsification equipment with excellent fluidics (a topic that would require its own post); (3) is technically more challenging to perform; (4) takes longer to complete than with 'co-axial' or one-handed irrigation and aspiration.

Next post: placing the new lens into the eye

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 5 of 9)

We are done preparing. Time to get to work:

The microscope was moved back into position...

Cataract surgery is microsurgery. Without a microscope it would not be possible to complete the steps to follow.

...and a paracentesis was created at the one and five o'clock positions...

A 'paracentesis' is a small incision (usually 1.0mm wide) in the cornea that allows the surgeon to place instruments or inject fluids into the eye (more on that next). In general when discussing orientation during surgery the eye is compared to a clock face with 12:00 the uppermost portion of the cornea (near the upper eyelid or brow) and 6:00 being the lowermost portion (near the lower eyelid or feet).

...through which 0.14 cc of Epi-Shugarcaine was injected into the anterior chamber.

'Epi-Shugarcaine' is a sterile solution of anesthetic and dilating medications developed by the late Dr. Joel Shugar. Not all surgeons use this solution. However, it can result in better anesthesia and dilation. I do not use it in all cataract surgeries but if a patient is on Flomax or has a small pupil I will instill Epi-Shugarcaine.

The 'anterior chamber' is a clinical term for the space between the iris (the colored part of the eye) and the posterior (backside of the) cornea (the clear front part of the eye on which a contact lens sits).

Viscoat was then injected into the anterior chamber firming up the globe.

Viscoat and Provisc are just two of many brands of viscoelastic. A 'viscoelastic' material, aka 'viscosurgical device' is a gel-like material that is placed in the eye in order to (1) create and maintain space to work-in, (2) protect the corneal endothelium. The corneal endothelium is made up of cells that pump fluid out of the cornea (keeping it clear). When these cells absorb the phacoemulsification energy (described in a later post) it 'shocks' them resulting in 'corneal edema' or a thickening of the cornea. Although usually self-limited, if this edema does not go away the vision would be blurred and a corneal transplant might be necessary. Thus, you can see why we would want to use something to protect the corneal endothelium.

A clear cornea temporal incision was then created with a metal keratome...

In order to remove the cataract and later place a new lens in the eye an incision must be made in the cornea. Currently there is no way around this. Thus, cataract surgery requires an incision. That being said, the incision is usually very small - on the range of 2.2-3.5mm wide.

This incision can either be made with a very sharp metal or diamond blade. Either one would make a standard razor blade appear dull by comparison. Because these blades must be manufactured to very exacting specifications they are quite expensive. A disposable metal blade runs anywhere from $35-70 per knife. Diamond blades, on the other hand, can be used hundreds of times before needing to be repaired or replaced. However, they are exceedingly expensive ($1,100-4,000) and are easily dulled or damaged.

...following which a continuous curvilinear capsulorrhexis was created using a bent needle cystatome on a Provisc syringe followed by capsulorrhexis forceps.

This is considered by many surgeons to be the most challenging element of the surgery. In order to get to the cataract an opening must first be made in the 'capsule' a delicate film-like material that holds the lens in place. This material is very thin (measured in microns, or millionths of a meter) and transparent. It is held in place by cables called 'zonules' that stretch it out over the surface of the lens.

Ideally, the surgeon wants to make a circular, or 'curvilinear' opening in the capsule. However, as you can imagine, tearing an opening in a thin, clear material on stretch is not a task for the faint of heart (considering that if the tear extends beyond the edge of the lens the rest of the cataract surgery becomes challenging, at best). There are two main ways of doing this: with a bent needle cystatome or with forceps. I use both. My father is a mechanic and taught me to use the best tool for the task at hand. As such, I find that the cystatome works best to start the capsulorrhexis and the forceps give me the most control over the shape of the opening.

Next post: getting to the actual cataract removal (finally)

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 4 of 9)

Today we continue our line-by-line evaluation of a typical cataract surgery operative report:

The patient was transported to the operating room in a supine position on a Stryker gurney.

This just means that the person about to have cataract surgery is lying face-up.

Once in the operating room, Tetracaine 0.5% drops were placed in the left eye following which Xylocaine 2% jelly was placed in the fornices on the left.

There are many ways to anesthetize the eye. Some doctors give an injection behind or beside the eye. However, this has risks associated with it which include perforating the eye (rare, but more likely in someone who is very nearsighted), bleeding, damage to the optic nerve, etc. For this reason, I prefer a 'topical' anesthetic. Anesthetic drops are placed on the eye for immediate anesthesia following which a gel is placed between the eyelids and eye in order to obtain a longer-lasting effect. The drops and gel do sting for a few seconds after they are placed in the eye, but there should not be any pain during the cataract surgery.

The microscope was moved into position and the patient was asked to look at the microscope light which she was able to do without difficulty.

Under topical anesthetic, movement of the eye is possible (indeed, preferred). This can be used to my advantage as a surgeon to direct the patient to look in a certain direction. However, if the patient cannot tolerate the bright microscope light then it might be best to give a retrobulbar or peribulbar injection of anesthetic (mentioned above). The benefits of giving an injection are that the anesthetic lasts longer and the eye is 'frozen' (meaning it cannot move during the surgery).

The microscope was moved out of position and the patient was prepped and draped in the standard sterile fashion using a povidone-iodine solution over the left face and lashes and a Betadine 5% ophthalmic solution in the fornices followed by a sterile saline rinse.

Prior to surgery the area around the eye must be cleaned, or 'prepped' using a Betadine solution to kill any bacteria on the skin (this helps to prevent infection). A dilute Betadine solution is also used to kill bacteria on the surface of the eye after which it is rinsed out using a salt solution or sterile water.

Steri-Strips were used to drape the lashes out of the operative field, following which Tegaderm was placed over the left face through which a lid speculum was placed.

One of the most commonly asked questions I hear is 'How will I keep my eyes open during surgery?' This is the answer to that. A sticky drape acts like scotch tape to keep the lashes away from the eye following which a device that looks like a bent paperclip is used to keep the eyelids open.

Now we are almost ready for surgery. In the next post we will actually get down to the business of surgery.

© 2009 David Richardson, MD

So then, How is Cataract Surgery done? (post 3 of 9)

OK, let's begin. Following is the first paragraph of a typical cataract surgery operative report.

Preoperatively, Nevanac, Vigamox, Omnipred 1% drops were prescribed or given to the patient to use in the left eye four times a day beginning four days prior to surgery.

Before cataract surgery many surgeons will have the patient start eyedrops to prepare the eye for surgery. These drops perform the following functions:

An anti-inflammatory

Anti-inflammotory drops generally are split into two categories: (1) steroids or (2) Non-Steroidal Anti-Inflammatory Drugs aka NSAIDs. There is some evidence that beginning drops a few days prior to surgery can reduce the inflammation associated with surgery. The results of these studies are suggestive but not conclusive so not all surgeons begin anti-inflammatory drops prior to surgery.

An antibiotic to protect from infection

Infection is one of the few complications of surgery that can lead to loss of vision or blindness. Therefore it is worth taking every precaution to avoid it. By starting antibiotics prior to surgery, the bacteria living on the surface of the eye and eyelashes can be reduced. Additionally, the antibiotic builds up in the corneal tissue resulting in a depot of antibiotic that is slowly released into the eye after surgery.

The brand of the drops each surgeon uses may differ, but most surgeons order at least one drop from each of the above categories.

On the morning of surgery, the following drops were placed in the patient's left eye every 10-15 minutes x4 beginning approximately one hour prior to surgery: Mydriacyl 1%, Phenylephrine 2.5%, Vigamox, Nevanac.

Mydriacyl and Phenylephrine are dilating drops. These are used to enlarge the pupil so that your surgeon can get good visualization of the cataract prior to removal. Again, the brand of dilating drops and method of instillation may differ but dilation is necessary for safe and effective surgery

Next post we will be looking at the following section of the operative report:

The patient was transported to the operating room in a supine position on a Stryker gurney. Once in the operating room, Tetracaine 0.5% drops were placed in the left eye following which Xylocaine 2% jelly was placed in the fornices on the left. The microscope was moved into position and the patient was asked to look at the microscope light which she was able to do without difficulty. The microscope was moved out of position and the patient was prepped and draped in the standard sterile fashion using a povidone-iodine solution over the left face and lashes and a Betadine 5% ophthalmic solution in the fornices followed by a sterile saline rinse. Steri-Strips were used to drape the lashes out of the operative field, following which Tegaderm was placed over the left face through which a lid speculum was placed.

So then, How is Cataract Surgery done? (post 1 of 9)

There are so many incorrect beliefs about how cataract surgery is done that I spend a fair amount of my time with patients simply re-educating them about cataract surgery as well as what results they can realistically expect after surgery (for example: most people will still need bifocals or readers after surgery with a standard lens implant).

There are plenty of explanations about how surgery is performed (and even a few descriptive videos or animations available online). However, these are all simplifications of the actual procedure. For anyone interested in more detail there are very few resources available to the general public. Fortunately, there is a detailed description of every cataract surgery performed in the USA. This description, known as the operative report (or 'op report') is generated by the surgeon after each case and becomes part of the medical record.

Unfortunately for those interested in reviewing these detailed reports, they are not available to the public as they are 'protected health information' (or PHI) that cannot be released except to a very limited number of approved entities (such as the insurance company) and individuals (such as the actual patient and his or her health care providers). Fortunately for the readers of my blog, I have created a draft of my standard operative report without any of the usual identifying information. Over the next two weeks I will publish this report as well as a line-by-line explanation of the terminology used in the report.

I believe this will be the only such example of an actual operative report template available online. Even if there are other PHI-stripped copies floating around on the net, the explanations I will provide over the next few posts are truly an exclusive inside look into the workings of a typical cataract surgery.

Next post: The operative report

So then, How is Cataract Surgery done? (post 2 of 9)

As promised, I have included a typical operative report in this post (it has been stripped of all identifying information). For anyone outside of the field of ophthalmology reading this will most likely be as clear as mud. Don't worry, over the next few posts I will clarify this post in excruciating detail. When you are done reading this series of posts, you'll probably know more about how cataract surgery is done than your own internist.

Procedure in detail:

Preoperatively, Nevanac, Vigamox, Omnipred 1% drops were prescribed or given to the patient to use in the left eye four times a day beginning four days prior to surgery. On the morning of surgery, the following drops were placed in the patient's left eye every 10-15 minutes x4 beginning approximately one hour prior to surgery: Mydriacyl 1%, Phenylephrine 2.5%, Vigamox, Nevanac.

The patient was transported to the operating room in a supine position on a Stryker gurney. Once in the operating room, Tetracaine 0.5% drops were placed in the left eye following which Xylocaine 2% jelly was placed in the fornices on the left. The microscope was moved into position and the patient was asked to look at the microscope light which she was able to do without difficulty. The microscope was moved out of position and the patient was prepped and draped in the standard sterile fashion using a povidone-iodine solution over the left face and lashes and a Betadine 5% ophthalmic solution in the fornices followed by a sterile saline rinse. Steri-Strips were used to drape the lashes out of the operative field, following which Tegaderm was placed over the left face through which a lid speculum was placed.

The microscope was moved back into position and a paracentesis was created at the one and five o'clock positions through which 0.3 cc of Epi-Shugarcaine was injected into the anterior chamber. Viscoat was then injected into the anterior chamber firming up the globe. A clear cornea temporal incision was then created with a metal keratome following which a continuous curvilinear capsulorrhexis was created using a bent needle cystatome on a Provisc syringe followed by capsulorrhexis forceps. Hydrodissection and hydrodelineation were then completed with a visible fluid wave and good nuclear mobility noted. Phacoemulsification of the nucleus was then completed using a horizontal chop phacoemulsification technique requiring 0.7 minutes of phacoemulsification at 19% power. The remaining cortex was then removed using bimanual automated irrigation and aspiration. Provisc was then injected into the anterior chamber and capsular bag following which the lens was inspected for proper power and good integrity. The lens was placed in the insertion device which was used to insert the lens through the temporal incision, guiding the leading haptic into the capsular bag. The trailing haptic was positioned in the capsular bag using a lens manipulator. The remaining viscoelastic was then removed using automated irrigation and aspiration, taking care that no residual viscoelastic was trapped behind the optic. A single 10-0 Vicryl suture was then placed in the temporal corneal incision and the knot was buried in the corneal stroma.

The incisions were then hydrated and the anterior chamber was formed to physiologic pressure (confirmed by intraoperative tonometry) at which pressure the incisions were checked and felt to be watertight and of good integrity. The lid speculum and drapes were then removed followed by placement of Vigamox drops in the fornices on the left. A shield was then placed over the left eye which the patient was instructed to keep on the eye except during placement of Nevanac, Vigamox, Omnipred 1% drops which she is to use including the day of surgery. She was instructed to avoid any heavy exertion and is to follow up in my office the day after surgery. She tolerated the procedure well.

How your Eye Doctor can tell if you have Dry Eyes

As discussed in an earlier post, one of the most common symptoms of dry eye syndrome is tearing. Even with an explanation of how this occurs, many are unconvinced. How do you know that your doctor isn't just telling you this to give you pause while he slips out of the exam room and on to his next patient. "Ah, the old dry eye ruse:" tell the patient that having too much tear is really related to having too little tear and disappear through the door while the unsuspecting patient is mulling this over.

Well, as much as the demands of modern medicine do limit that amount of time doctors can spend with their patients (and, BTW, this really is not in the doctors control - topic for another post), the dry eye explanation is not a ruse. Dry eye syndrome is something that can often be objectively diagnosed at the slit lamp (aka biomicroscope) in the eye doctor's office. Following is a description of how an ophthalmologist would typically diagnose dry eye syndrome.

Assess Symptoms
As with most medical disorders, the diagnosis of dry eye syndrome is 80% listening to the patient. Following are the things I listen for:

What are the symptoms?

Tearing

Ocular irritation

Foreign Body Sensation (a sense that something is in the eye)

Red eye

Tired eyes

Flucturating vision with certain activities

When do the symptoms occur?

First thing in the morning

Later in the day

After extended periods of concentration

With reading

With computer use

With TV use

What medications are currently being used?

Blood pressure medications

Diuretics

Hormone replacement therapy

Allergy medications

Examine the Eye
Even with the best listening, the diagnosis must be confirmed by examining the eye. Following are the things I look for:

A decreased tear lake (a thin tear film over the cornea)

A decreased Tear Breakup Time (the tear film is not stable)

An irregular corneal surface

Dry patches on the corneal surface

Test the Tear Film
Sometimes special testing is required to diagnose dry eye syndrome. Following are some common tests for dry eye syndrome:

Schirmer's testing: evaluates how much tear is produced in five minutes

A decreased Tear Breakup Time (the tear film is not stable)

Lissamine Green staining: reveals devitalized corneal surface cells

Rose Bengal staining: also reveals devitalized corneal surface cells

Lactoferrin level test: a low level indicates dry eyes

Not all of the above examination or testing methods are necessary to diagnose dry eye syndrome. However, some combination of the above is used to provide a more objective assessment of the presence or absence of dry eye.

10 Essential Items Everyone Must Be Aware of Before Selecting An Eye Doctor

A lot of people consider their sight to be their most important sense. Yet, every day thousands of people have surgery on their eyes without having done any research on their eye surgeon. Who does your eye surgery is one of the most critical decisions you will make.

It doesn't take a large investment of time to choose your surgeon if you know how. The following listing of Ten Essential Things Everyone Must Be Aware of Before Selecting An Eye Surgeon will instruct you how. With this list you can decide on an excellent eye surgeon in less time than many people dedicate to selecting their next automobile.

1. Don't limit your selections to just those eye doctors in your insurance network.Despite what your insurance company's marketing brochures may indicate, the essential factor in deciding who is "in-network" is who is willing to sign that insurance contract. Presently there is no well-grounded method of scoring doctors and any insurance company that suggests their network of doctors is the most qualified is disingenuous at best.

2. Ask those you trustGood sources of information include your primary care physician, optometrist, and friends who have had eye surgery. Even better references include the operating room technicians and staff at your local hospital. They are often in the operating room with the cataract surgeon and recognize which surgeon is the most skilled. Nurses are frequently very helpful people and will often be disposed to respond to your question. The difficulty will be making it beyond the hospital's automated telephone maze and getting access to a live operating room nurse.

3. Research your eye surgeon's trainingWhere did your eye surgeon get her education? You may not know which training programs are the best, but it is simple enough to find their rankings once you know where your surgeon trained. Two objective resources are U.S. News & World Report's Annual rating of Medical Schoolsand Eye Hospitals

Don't get too caught up on the rating order - if your physician trained at a top 20 program he experienced superb training.

4. Research your eye surgeon's State LicensureYour physician must be licensed to practice medicine in his state. In addition to confirming licensure, many state license internet sites will also inform you if there is any history of corrective or legal action against your cataract surgeon. In California you can look up this data online at http://www.medbd.ca.gov/lookup.html

5. Confirm that your Eye Doctor is Board CertifiedBoard certification is a type of "seal of approval" for all doctors. In order to acquire certification an eye surgeon must successfully pass both a written and oral examination. In addition, younger eye surgeons must recertify every decade - a process that can take up to three years to complete. You can confirm that your ophthalmologist is board certified by checking the internet site: http://www.abop.org or http://www.abms.org

6. Look up your surgeon's Medical Practice SiteAssuming the above background check is favourable you can sometimes get useful information from your eye doctor's web site. Although some sites do provide educational materials, keep in mind that the website's essential goal is to market the practice. You won't see anything unfavorable about your doctor there, but it can confirm the constructive data you have already found and give you some insight into the ophthalmologist's background and medical practice philosophy.

7. Find out what others have gone through.Are testimonials available online (eye surgeon ranking internet sites or medical practice site)? Are testimonials accessible in your eye surgeon's reception area for your review? Will your cataract surgeon offer you the contact information of someone who had surgery that you can talk to?

Keep in mind that Federal privacy rules restrict the amount of information your cataract surgeon may be able to issue you regarding other patients who have had cataract surgery. Notwithstanding, it shouldn't be too onerous for your cataract surgeon to come up with a live person who would be willing to talk about the eye surgery experience with you.

8. Learn how many cataract surgeries your doctor has performed.There is a reason they call it the "practice of medicine." Just like a sports professional, an eye surgeon's skills improve with practice and experience. Every surgery differs in its "threshold" number (the number of surgeries necessary for the typical surgeon to become proficient). For cataract surgery I think this number is probably around 500.

If you are uneasy inquiring straightaway then take someone with you to the appointment to ask for you. This is a critical question. These are your eyes. You only have two. Get over your reluctance. Just ask.

9. Meet the Physician.The above research can give you an idea if your cataract surgeon is well-qualified to perform your surgery. Nevertheless, you cannot know if this is the ophthalmologist you want operating on your eyes until you meet with him. In addition to confirming his or her certifications, you need to be comfortable with this person.

Trust is a fundamental consideration that can't be sufficiently built up without encountering your cataract surgeon face-to-face.

10. At Long Last, get a second impression.Most people wouldn't buy an auto without test driving it and at least one other car. Why would you limit your choice of eye doctor because "he's on my insurance plan" before getting a sense of how comfortable you are with the choice your insurance has made for you? This is a very serious decision.

Unless you are totally at ease with your surgeon, get a second opinion.The most experienced doctors do not mind that you have or are going to get a second opinion. In fact, one quick test of your ophthalmologist's comfort with his or her own ability is to let him know that you would like a second opinion. If the ophthalmologist becomes defensive about this then you know the second opinion was a superb idea, after all.

In summary, there are many things you can easily do to affirm that you have made a good decision about who will perform your cataract surgery. Looking At the importance of your vision, you owe it to yourself to complete this inquiry before having cataract surgery.

Would you like your Cataract Surgery with a Double Shot?

Cataract surgery and coffee have something in common. Five to ten years ago they shared this attribute: there were few, if any options. You wanted coffee? OK, would you like that with cream or sugar? Had cataracts? Would you like... Actually, there were no real options five to ten years ago. If you needed surgery it was scheduled and your surgeon chose the intraocular lens (IOL) for you.Now, however, there is a dizzying array of options available to anyone who saunters up to the barista or the cataract surgeon. Coffee? Would you like that in a Grande or Venti? Cream, lowfat milk, or soy? Vanilla, sugar-free vanilla, caramel, mocha, or flavor-of-the-week? The same is now true of cataract surgery. Would you like a spherical or aspheric IOL? Astigmatism correction? How about the ability to see distance, intermediate, and up close? , You can now select for two out of the three -- a major improvement over just a few years ago.

So how do you choose? As a cataract surgeon who has performed over 2,000 cataract surgeries, I can tell you it is not an easy decision. You only have two eyes so it's an important decision to make if you are presently in need of cataract surgery. (If you're not in need now, you should be assured that the technology improves every year – increasing your menu of choices by the time you’re ready.). The best way to begin is to consider your goals.

With coffee, there is one initiating decision: caffeinated or decaf? With cataract surgery there is one key question: "Do you mind wearing glasses?" If the answer is "No," then you're done. Stop reading this article because the rest is not applicable to you.

If you dream of throwing away your glasses after cataract surgery, keep dreaming.
There are currently no IOLs that will allow you to do that. If, however, you have certain activities that you would like to do without glasses and wouldn't mind wearing glasses "occasionally," then read on - because the newer advanced IOLs can provide for that. Following is a list of available alternatives sorted by need. Simply find the description that fits you best to find the IOL for you.

One caveat: all of the options except the first will require an out-of-pocket expense. Medicare and most insurances do not pay for the IOL "upgrades." If you want your insurance to cover the entire tab then Option #1 is for you.

Option #1: You don't mind wearing glasses all the time. Congratulations. The standard IOL covered by insurance will meet your needs just fine and with the money you've saved you can upgrade your coffee for a year or so at your local barista. Take note, however, Medicare does not cover the fee for refraction (an exam to determine what glasses you will need after surgery), so save back $50-100 (plus the cost of those designer frames) for this.

Option #2: You would like good distance vision without glasses but don't mind wearing glasses to use the computer and read. You may be a candidate for either an aspheric or toric IOL. The aspheric IOL corrects what are called "higher order aberrations" resulting in excellent distance vision. However, if your cornea has any significant astigmatism, this will have to be corrected with either a "toric" IOL or corneal refractive surgery. Both of these would be at an additional cost.

Option #3: You would like good distance and intermediate (computer) vision without glasses but wouldn't mind wearing glasses for reading. You have two options available to you: the ReZoom multifocal IOL or the Crystalens accommodating IOL. The ReZoom IOL simultaneously focuses two images onto your retina so you can see both distance and intermediate objects at the same time. The trade-off, however, is that there will be small circles (halos) around lights at night. Most people get used to this with time but a small number of people (about 5%) find these halos to be a significant distraction. The Crystalens uses what is called pseudo-accommodation: it uses tiny muscles in the eye to move the lens back and forth changing the focusing power of the IOL. Although there are no halos associated with this IOL, not all people are able to "train" their eye muscles sufficiently after surgery to get the desired range of vision.

Option #4: You would like good distance and reading vision without glasses but wouldn't mind glasses for intermediate (computer) vision. You also have two options available to you: the Alcon ReSTOR IOL or the AMO Tecnis IOL. Both use what is called "diffractive optics" to split light into both a distance and a near image. Since two images are simultaneously focused on your retina, there will be small circles (halos) around lights at night. As with multifocal IOLs, most people get used to this with time but a small number of people (about 5%) find these halos to be a significant distraction. Glasses are often still required for intermediate (computer) work.

An additional caveat: no matter which IOL you choose, you may still need night-time glasses. The reason for this is that your pupil dilates in the dark allowing rays of light from the edges of your cornea into the eye. These rays are focused at a different strength than those from the center of the cornea so you end up a little near-sighted when driving. Generally, a simple pair of night-driving spectacles correct this condition.

If you are currently considering cataract surgery I hope this helped you make this ever-more-difficult decision. If you don't need surgery yet, I promise to provide updates on my website http://www.sgveye.com/ or blog whenever there are significant technological changes that increase your menu of choices.

"My eyes can't be dry. They tear all the time."

I'm going to take a break from discussing cataract surgery today and focus on something even more common: dry eye syndrome. One of the most common eye diseases I see is dry eye syndrome. The most common symptom of dry eyes: tearing. The most common response I get when I tell someone with tearing that they have dry eye syndrome: "My eyes can't be dry. They water all the time."

Yes, it appears to be contradictory but it's a fact. The reason dry eyes lead to tearing is as follows: dry eyes (like dry skin) are more sensitive to irritation; irritation is interpreted by the brain as "there is something in the eye;" the brain's response to this is to flush it out resulting in a flood of tears being release by the lacrimal gland. It's an issue of too much, too late.

It is common for the eyes to dry out with any activity that involves extended concentration such as computer use. In addition to tearing, symptoms of dry eyes include: an "awareness " of the eyes, soreness, redness, discharge, "sticky" eyes, itching, foreign body sensation, blurred vision, "tired" eyes.

Treatment options include the following:

1) Tear Replacement Therapy (artificial tears). There are so many brands out there it is difficult to recommend just one. Some of the better brands include:

- Blink

- Endura

- Optive

- Refresh

- Soothe (my personal favorite)

- Systane

- Theratears

Each one is formulated differently so which one works best is hard to determine without first trying it.

2) Nutritional Supplements. There is some evidence that taking Omega-3 fatty acids (such as fish oil or flax seed oil) by mouth can benefit the symptoms of dry eye. These come in gelcaps and are generally recommended once or twice a day with food.

3) Prescription medication. Currently only one medication, Restasis, is approved by the FDA for treatment of dry eye. This must be used twice a day for at least a month. It stings, is expensive, and only works in 50% of people who take it.

3) Punctal plugs. When someone's eyes are not producing enough tears to keep the eyes lubricated it does not help that tears drain through "puncta" into the nose (this is why you get the sniffles when you cry). The solution: plug these drainage duct with small silicon plugs. This can be done by an eye doctor in the office. It is a painless procedure that only takes a few minutes.

Why your friend didn't really have his or her cataract removed with a laser

Not a week goes by in which I am told by a patient with 100% conviction that her friend had cataract surgery done with a laser. Although it is remotely possible that this conviction is well-founded, I'm going to explain why it's far more likely that her friend is mistaken.

In fact, the vast majority of cataract surgeries are done using ultrasound energy (also known as phacoemulsification). That being said, it is possible (though unlikely) that the friend in question had laser cataract surgery. During the late 1990s and into the early 2000s there was a brief interest by a very few surgeons in using a laser to remove the cataract. Even so, this still required making a 3mm incision in the eye (so no, you cannot avoid "going under the knife").

However, the laser technology was far inferior to the advanced ultrasound technology (which has been steadily improved upon since the 1970s). The only surgeons still using this short-lived laser technology are those who invested in it and feel they have to get some mileage out of their investment. Oh, and it does sound sexy to say that a laser is used to remove the cataract.

Ultimately, if someone has a cataract the best option available in the US is an advanced ultrasound technology called "cold phaco." This beats the pants off any laser still hanging around. Perhaps in a future post I'll discuss cold phaco in more detail.

So why, then, are so many people convinced that they had their cataracts removed with a laser? The answer is that a laser is used to treat "after cataracts." This term is actually a misnomer for posterior capsular opacification (or PCO). A PCO is actually a type of scar that forms behind the IOL months to years after cataract surgery. Think of it as similar to frost on a window.

In order to remove this haze and improve vision a YAG laser is used to tear open the capsular bag behind the intraocular lens (IOL). Prior to the use of this laser surgeons used to poke a needle into the eye and scratch the capsule to tear the scar out of the visual axis. Needless to say, the laser is a big improvement over the needle.

As YAG capsulotomy is the second most commonly performed surgery in the world (cataract surgery is the most commonly performed surgery), it is not surprising that many people mistakenly think that cataracts are removed by lasers.

Click on this link to read more about posterior capsular opacification and YAG capsulotomy.

"Name that Tune" Cataract Surgery

Some of us remember the game show "Name That Tune" in which contestants would compete to name a tune in the least number of notes. The back and forth would go something like this:

Contestant 1: "I can name that tune in 5 notes."

Contestant 2: "I can name that tune in 4 notes."

And so on...

At times it would get just ridiculous with a contestant trying to name a tune in only one note. This type of one-upmanship has a place in entertaining game shows but unfortunately has found its place in modern cataract surgery.

We've all heard that cataract surgery only takes 15 minutes, or 10 minutes, or some other ridiculously small amount of time. And, it is true that a talented cataract surgeon can usually complete a straightforward, uncomplicated cataract surgery (from incision to closure) in 10-15 minutes.

Unfortunately, the impression is that because the surgery only takes a small amount of time it is "a piece of cake" to do. Nothing could be further from the truth. Although it is every surgeon's goal to make the surgery "a piece of cake" for the patient, cataract surgery (done correctly) takes a great deal of preparation, concentration, and skill.

Have you ever seen a Cirque du Soleil performance? The way those performers gracefully execute their acrobatics conceals the intense concentration, strength, agility, and balance required. Indeed, the best performers "make it look easy." If you've ever gone home after a show and tried to replicate even the easiest of the positions you probably threw out your back.

I'm no athlete, but I know those Cirque du Soleil performers have practiced for hours each day, every day for years to make their 5 minute performance look "easy."

A similar kind of dedication, skill, and innate talent is required to become an expert cataract surgeon. Most cataract surgeons in training take one to two hours to complete their first cataract surgery. Over the next couple of hundred cases they will often improve their skills enough to complete surgery in 20-30 minutes. Most surgeons never get down to 15 minutes per surgery.

Does it matter?

It does, but not for the reasons you may be thinking. Unfortunately, because some ego-centric surgeons started to advertise that they could complete cataract surgery in less than 10 minutes, Medicare and other insurances have cut their rates of payment from an inflation-adjusted rate of $6,000 in the 1970s to a little over $600 today. What this does not recognize is that (1) most surgeries take longer; (2) cataract surgery involves a significant amount of time planning prior to surgery; (3) there is a value that should be assigned to the skill required to perform modern cataract surgery.

Unfortunately, this reduction in perceived value of cataract surgery has resulted in pressure from surgery centers and hospitals to cuts costs, cut time, and cut corners. My average cataract surgery may take only 12 minutes, but if I feel that I need to take a little longer and place a suture I'll do so. However, I know that the surgery center feels the financial pain every time I do so as operating room time is very expensive (as is the suture). I'm just waiting for the day when the center tells me, "I'm sorry Dr. Richardson, but we can no longer stock that suture (or other device) because we lose money every case it is used.

Modern cataract surgery is a truly amazing convergence of technology and skill. It is a joy for most cataract surgeons to perform and is usually a "piece of cake" for the patient. However, modern financial constraints are placing undue burdens on both the surgery center and surgeon to cut costs in an attempt to keep pace with ever decreasing Medicare and insurance reimbursement.

There are appropriate venues for competitive one-upmanship - game shows, for example. But when reimbursement pressures result in surgery centers and hospitals competing for cataract surgeons based on how much they can save in time and equipment costs, I fear that patient safety could be at risk.

Softserve IOL?

Modern cataract surgery has come a long way from the days of "couching" (an ancient surgery that essentially involved sticking a needle in the eye and pushing the cataract out of the visual axis). Nevertheless, modern surgeons still worry about the most devastating complication of cataract surgery: post-operative infection, or "endophthalmitis." Granted, in ancient times this risk was probably quite common. Today rates of post-operative infection range from 1 in 500 to 1 in 2,000 (depending on the study).

The single largest contributor to risk of infection with any surgery is incision size. The smaller the incision, the lower the risk of infection. With cataract surgery, the larger the incision, the greater the risk that bacteria can enter the eye with blinking. Current cataract surgery requires an incision of only 3mm in length. Now, one might think that an incision size of less than 3mm is pretty small, but there is evidence that if we could get the incision below 2mm it could be truly water-tight keeping bacteria out of the eye.

So, what's keeping us from doing everything through a 2mm incision? We can now remove the cataract through a 2mm incision safely. The problem is getting a new lens (IOL) into the eye. Presently all lenses must be folded or placed in a cartridge and squeezed through the incision. The smallest incision that we can tire-iron these lenses through is 2.2mm (and that's pushing it - pun intended).

If only there were a way to get an IOL through a smaller incision...

Turns out there are two material technologies that could be used to place an IOL through such a small incision. I've already mentioned the SmartLens material which changes shaped according to temperature.

The other material being researched is a polymer that could be injected through a small incision into the capsular bag (this holds the IOL in position) where it would then "cure" or harden into the correct shape.

There are, however, many technical hurdles that must be overcome prior to implementing this technology. For one, how do we know how much material to place in the capsular bag. Presumably, the more material we place in the bag the stronger the IOL will be. But how do we customize this to the needs of that individual eye?

Additionally, how do we cap off the polymer so it doesn't leak out of the bag? Finally, there is the issue of cure rate. If the material cures too fast the surgeon won't have time to make the adjustments necesary for a good refractive result. Too slow and surgeons won't use it (more on the modern time-constraints of surgery in a later post).

I'd give this technology a high probability of appearing on the horizon, but I'd set that horizon at 5-10 years at least.

Is blue light special? (post 4 of 4)

You've now read a summary (by no means exhaustive) of the arguments for and against using a blue-blocking tint in IOLs. So, is it a thumbs up or thumbs down? As you might have guessed from the first paragraph of the first post in this series, there is no straighforward answer.

Those who are strongly in favor of using a yellow tinted IOL cite the evidence supporting an association of macular degeneration with shorter-wavelength blue light while pointing out the lack of strong evidence supporting any disruption in sleep-wake cycles or notable detriment in color perception.

Those opposed to the use of a yellow tinted IOL cite the evidence supporting a disruption of sleep-wake cycles, and loss of night vision and color sensitivity with blue-blocking IOLs while pointing out the lack of strong evidence supporting a causal effect of blue light on the progression of macular degeneration.

The answer, clearly, is that we don't know. So what is one to do? Most likely, if you have cataract surgery in the US you will have a blue-blocking IOL implanted in your eye as the Alcon AcrySof is the most commonly used IOL by US surgeons. If this bothers you then discuss it with your surgeon. If this all seems like much ado about nothing then I wouldn't lose any sleep over it.

...or will you (pun intended)?

Is blue light special? (post 3 of 4)

In part 3 of my 4 part series on blue-blocking IOLs I am going to discuss the reasons why it might not be such a great idea to implant a blue-blocking IOL into the eye.

Color perception concerns

If you have ever tried on a pair of blue-blocking sunglasses, do you remember your initial impression? Many people find the yellowing of their world to be a bit disconcerting. Contrast is usually notably improved, but at what cost? I personally do not like the tint though I do appreciate the improved contrast sensitivity when I'm on the slopes.

But, unlike my ski goggles, an IOL cannot be put in or taken out based on one's activities. Once it's placed, it's there for life (one hopes, anyway). Does a tinted IOL significantly affect color perception? Current studies are conflicting on this point. Of those who have had a tinted IOL placed in one eye and a non-tinted IOL in the other most do not perceive a difference. However, some do notice it. It may be that those who notice this color difference are the ocular equivalent of audiophiles. Most of us cannot tell the difference between a song played back on CD or 128bit MP3 - but run the same comparison by a professional musician or audiophile and the difference will be obvious to them. Could the same be true of color perception?

Possible disruption of the natural circadian rhythm

Our normal sleep-wake cycles are set by exposure to light - specifically, the blue wavelengths of light. Blue light suppresses the production of melatonin which is thought to be the main hormone that controls our sleep-wake cycle. Theorhetically, blocking these wavelengths of light could disrupt this cycle. However, the available clinical studies are not conclusive one way or the other.

Lack of strong evidence of any benefit

The blue-blocking filter in the Alcon Acrysof IOL mimics the yellow tint present in the average 50 year old human lens. This begs the question: why would anyone want an IOL that mimics a 50 year old lens? The answer presumes that there is a definite benefit to blocking these wavelenghts of light. But is there? And if there is not, wouldn't you rather have a lens that mimics that of a 20 year old?

So, is there or isn't there a benefit to blocking the shorter wavelengths of light? I'll pick up this thread in my next post.

Is blue light special? (post 2 of 4)

In my last post I introduced the controversy concerning blue light filtering IOLs. You may be asking yourself, "If it's good for skiers and helps with contrast sensitivity, why wouldn't I want an IOL to block the blue rays of light?" Tomorrow I'll address that question.

First, let's look at the reasons touted to block the far blue spectrum of light and clarify that no one is suggesting that all blue light be blocked, only the shorter "near-ultraviolet" wavelengths of light. The main reason touted by those in favor of blocking these shorter wavelengths of blue light is the evidence that these wavelengths may increase the risk of macular degeneration.

This evidence is largely culled from population-based studies. Essentially a large number of people were observed for years and examined for the development of various diseases such as macular degeneration. Those who developed macular degeneration were compared to those who didn't. Attributes such as nutrition, activity, and environmental exposures were evaluated. A correlation between macular degeneration and exposure to light was noted.

Additionally, there are some studies that have suggested a correlation between cataract surgery and worsening of macular degeneration. There are many reasons why this could be (inflammation, ease of detecting macular degeneration after a cataract is removed, etc.). One theory is that because most synthetic IOLs allow a greater spectrum of light into the eye than the natural cataractous lens that these rays of light may be capable of damaging the retina.

Indeed, there is laboratory evidence of "phototoxicity" when retinal cells are exposed to near-ultraviolet light. This is suggestive that a similar effect could occur in a living eye.

So, with the above evidence suggesting that a blue-blocking IOL may protect from macular degeneration and improve contrast sensitivity, why wouldn't all surgeons be using them?

As it turns out, there are quite a few reasons not to place a blue-blocking IOL in the eye. I'll discuss the main arguments against use of these IOLs in my next post.

Is blue light special? (post 1 of 4)

There is a war being waged in ophthalmology with all the zeal of a religious war. And, like a religious war the two camps each believe with all their heart and soul that they are right and doing what is best. So what could make an IOL so controversial?

Cataract surgery has a long history of controversy. Early cataract surgery shared a complication of modern surgery: blindness. Whereas this is a rare complication of modern surgery, it was relatively common in early attempts to remove the cataract. What was probably uncommon was finding someone willing to perform cataract surgery. This was due to the Code of Hammurabi which prescribed a very harsh penalty for cataract surgery gone wrong: cutting off the surgeon's hands. Compared to the fee for cataract surgery (ten shekels of silver - not even gold!) the risks do seem to have outweighed the benefits to the ancient cataract surgeon.

Fast forward to the mid-1950's: Dr. Harold Ridley firsts attempts to place a lens inside the eye after removing cataract surgery. He was severely ostracized by the medical community for what was seen as reckless behaviour. Here in the US the FDA was even ready to ban the use of IOLs until Robert Young (the actor who played Marcus Welby, M.D.) testified in favor of the IOL.

So what is the current source of online and in-print flame wars among otherwise professional and staid ophthalmologists?

Blue light.

Huh?

Yep, blue light. Or, rather, the blocking of this light with a yellow-tinted filter. The correct way of thinking about these filters is not that the filter adds yellow, but rather that it absorbs blue (when blue is subtracted from the visible light spectrum an object takes on a yellow tint).

Skiers have known for years that blocking blue light with a yellow tint increases contrast sensitivity on the slopes. "Blue blockers," or yellow-tinted sunglasses are also very popular with those involved in watersports. There is even a pair of glasses advertised in some magazines to cut glare from nighttime driving that has incorporated a yellow-tint.

So, if filtering the blue spectrum of light provides the benefits mentioned above, why wouldn't a blue light filtering IOL be a good idea? Indeed, the major manufacturer of IOLs in the US (Alcon) does not offer any of its popular single-piece IOLs without a blue-filtering pigment.

Herein lies the controvesy. Not everyone agrees that filtering blue light is a good idea. It's one thing to put on a pair of sunglasses with a yellow tint. But, should we really be surgically implanting these lenses in the eye after cataract surgery?

In my next three posts I will summarize the support for and against blue light filtering IOLs.

What the Prostate has to do with Cataract Surgery

I'm going to take a break from discussing IOLs in order to summarize another very important talk given by David Chang, M.D. from UCSF. Really, anyone in the Bay area who needs cataract surgery should stongly consider at least an opinion from Dr. Chang. Mind you, I've never been in surgery with him and have absolutely no financial connections to him. However, his papers and presentations (which include videos of his work) are awe-inspiring among cataract surgeons (at least this one).

First, a little background on cataract surgery. Prior to cataract surgery the iris must be dilated in order for the surgeon to get to the lens (cataract). This is done both to obtain good visualization of the cataract and to protect the pupil which is a very delicate tissue and is easily damaged when it comes into contact with metal instruments.

Dr. Chang noted a few years ago that the iris of certain patients would become "floppy" during cataract surgery and dilation would be lost. This resulted in a very poor view through the small pupil, increased intraoperative complications (secondary to the poor view), and damage to the iris (because it flopped around inside the eye during surgery). This syndrome became known as Intraoperative Floppy Iris Syndrome (or IFIS).

David Chang, MD, and John R Campbell, MD, with the help of others (whose names I cannot recall - my apologies), collected all the information they could about these patients and discovered that they all had one thing in common: use of a prostate medication called Flomax®.

Flomax® (or tamsulosin) is a selective alpha-1 adrenergic antagonist that relaxes the smooth muscle of the prostate allowing men with Benign Prostatic Hyperplasia (BPH) to urinate more easily. Doctors also prescribe these medications for women as a treatment for urinary retention. Unfortunately, it appears that Flomax® has a permanent effect on the iris muscle that greatly increases the challenge of cataract surgery.

Other medications in this class include the newly released Rapaflo® (silodosin), as well as a group of medications termed "non-selective" alpha-1 adrenergic antagonists which include Hytrin® (terazosin), Cardura® (doxazosin), and Uroxatral® (alfuzosin). These non-selective drugs are less likely to result in IFIS.

Fortunately, if a cataract surgeon is aware that someone is taking one of these medications, he or she can take some additional precautions prior to or during cataract surgery to minimize the risks of IFIS. If you are taking any of the above medications or if your primary medical doctor is recommending that you start, it is a good idea to let your ophthalmologist know about it. If you don't yet have an ophthalmologist, this would be a good time to get one.

SmartLens or science fiction?

All currently available IOLs have one thing in common: they are the same shape in the manufacturer's package as they are inside the eye. In order to get these IOLs through a small incision and into the eye these lenses must be folded or squeezed into an insertion cartridge and "delivered" into the eye.

Just as in the delivery of a baby, squeezing through a small canal has its risks. The IOL can be deformed or torn. The incision can be stretched resulting in a leaky wound. The later can result in an increased risk of infection.

Enter the thermoplastic hydrophobic acrylic material. This material has a science fiction-like ability to change shape as temperature changes. At room temperature it is shaped like a rod allowing the surgeon to easily slip it through a small incision and into the eye. As the material heats up to body temperature it transforms into a biconvex lens. Truly amazing!

This IOL is still experimental so we won't see it for a couple of years (at least). Nevertheless, it is an exciting technology and worth watching.

A NuLens for Presbyopia Correction

Probably the most unique approach to the problem of presbyopia-correcting IOLs is the mechanism used in the NuLens. This lens tries to mimic the natural process that occurs in some water birds such as penguins. These birds' eyes have a rigid iris and a soft lens. To increase the power of the lens these birds have a muscle that pushes the soft lens up against the iris resuling in a protrusion of the lens through the iris. This central bulging results in a greater power of the lens.

One way to picture how this works is with a peanut butter sandwich. If you are generous with your peanut butter and press the two slices of bread together the peanut butter will ooze out the sides of the bread. Now instead, imagine that you have created a central hole in the middle of the top slice of bread (the iris). If you push on the bottom slice of bread the peanut butter (the lens) will bulge forward through the central hole. This is essentially how the lens of a water bird works.

The NuLens is essentially a very small peanut butter sandwich with the peanut butter replaced by a silicon gel and the bread replaced by a rigid clear material. Initial studies in monkeys have been very promising. However, it will be awhile before this is approved for use in humans.

The recession will be over long before the FDA gives its blessing so it is not going to be an option for you if you need cataract surgery in the next couple of years. Nevertheless, the technology is exciting and many baby boomers will have quite a few awesome choices when it is time for them to have cataract surgery.

The Tetraflex IOL

Of the new technologies presented at the joint meeting of the American Society of Cataract and Refractive Surgery (ASCRS) / University of California, Los Angeles (UCLA) Jules Stein Institute in Century City, the Tetraflex was probably the least likely to be remembered.

Lenstec Tetraflex IOL
This IOL platform, presented by Paul Dougherty, M.D., seemed to have only one benefit over multifocal IOLs: minimal post-operative glare. However, that benefit already exists with the Crystalens IOL.

This talk actually began with a discussion of the near acuity patients really need to read magazines, newspapers, etc. After a not very convincing explanation about why we really don't need to see the equivalent of 20/20 up close, Dr. Dougherty presented results that were objectively worse than what any of the presently available IOLs were capable of delivering.

One caveat: the patients in his study preferred the Tetraflex over the Crystalens even though the vision from the Crystalens eye could see smaller letters on the near eye chart. Now, I'll be the first to admit that our visual requirements in the real world do not directly correlate with what we can see on an eye chart. So, it is possible that the vision patients experience with the Tetraflex is somehow superior to what is measured with the eye chart.

It will be awhile before this IOL is approved for use in the US. Unless studies are able to show a clear benefit of this IOL over the currently available Crystalens, however, I seriously doubt this lens will become a major player in the IOLs offered by most surgeons.

A new paradigm in IOLs - The Synchrony

This first week of my blog I am summarizing some of the exciting new technologies presented at the joint meeting of the American Society of Cataract and Refractive Surgery (ASCRS) / University of California, Los Angeles (UCLA) Jules Stein Institute in Century City.

Yesterday I discussed the most exciting new IOL technology on the horizon for monofocal (single-distance) IOLs. Today, I'm going to talk about what I think is the most exciting technology in the "presbyopia-correcting" IOLs.

First, a word about presbyopia. When we are young, our eyes are able to focus over a wide range from distance to near. As we age we lose this ability to change focus. Eventually, we need to help our eyes with the near portion of this range with reading glasses, or "cheaters."

Currently, the only options available to return that range of vision involve removing the natural lens (or cataract) and replacing it with a multifocal IOL (more on these in a future post) or accommodating IOL. The problem with current multifocal IOLs is that they result in little rings around lights at night. The problem with the currently available accommodating IOL (the Crystalens) is that is doesn't work for everyone. So, what's on the horizon...

Synchrony IOL
Visiogen
This lens was presented by David Chang, M.D. (UCSF) who is one of the most impressive cataract surgeons alive today. It uses a unique two-lens approach to providing a range of vision (distance and near) after cataract surgery. Once inserted into the eye these two lenses would move relative to each other resulting in a variable range of vision.

Unlike most presently available presbyopia-correcting IOLs this lens does not result in halos or glare after surgery. The initial results are very impressive and I am looking forward to offering this IOL to my patients as soon as it becomes available in the US.

As it is such an unusual type of IOL (two lenses instead of one) many surgeons will not be comfortable implanting this IOL when it first becomes available. Nevertheless, this may be worth searching out as the initial results are quite impressive. I'll keep this blog posted when new results are available as I'm very bullish on this IOL.