The ISRS/AAO is pleased to announce its upcoming meeting in the exotic and beautiful city of Istanbul from May 26 to 28, 2006. This meeting, International Refractive Surgery: Art and Science, is held in partnership with the Refractive Division of the Turkish Ophthalmological Society. Program chairs Richard Lindstrom, MD, and Omer Faruk Yilmaz, MD, promise an extraordinary learning experience. -- Marguerite B. McDonald, MD, FACS

CLINICAL UPDATES
- Twelve pearls for early success with IntraLase
- Good outcomes obtained with topography-guided treatment for irregular astigmatism
- Women on hormone replacement therapy appear to have an increased risk of refractive regression after LASIK
- High axial length appears a risk factor for retinal detachment following PIOL implantation for high myopia
- Good outcome following infectious keratitis post-PRK dependent on early diagnosis and aggressive management
- Toxic anterior segment syndrome linked to ointment seeping into the anterior chamber after cataract surgery
- Pupil size affects post-LASIK higher-order wavefront aberrations and contrast sensitivity
- Visual recovery time appears quicker with single-piece hydrophobic acrylic foldable IOL
- AcrySof ReSTOR IOL can help patients reduce their dependence on glasses
- Toric phakic intraocular lens can correct high to moderate hyperopia combined with astigmatism

ISRS/AAO INFORMATION
- Journal of Refractive Surgerynow publishes nine times a year and includes online advanced release
- Housing and tour information for the 2006 ISRS/AAO meeting now live
- Registration for the 2006 ISRS/AAO meeting is now closed, but you can still register onsite
- Will you need a U.S. visitor's visa to attend the Joint Meeting in Las Vegas?
- Upcoming Meetings

INDUSTRY NEWS
- An AAO and ASCRS sponsored study: refractive procedures flat, cataract procedures down
- U.S jury awards LASIK patient $3 million

CLINICAL UPDATES

Twelve pearls for early success with IntraLase
From preparing staff to surgical technique, Perry S. Binder, MD, provides invaluable insight into integrating this exciting new technology into your practice.

Good outcomes obtained with topography-guided treatment for irregular astigmatism
This prospective, non-comparative case series included 11 patients (16 eyes) whose irregular corneal astigmatism was caused by trauma or previous corneal surgery. Surgery was performed using the Allegretto wave excimer laser and T-CAT software. Ten eyes had LASIK enhancement with a new cut or flap lift; six underwent PRK due to limitations in the corneal thickness. At six months, both groups experienced a significant reduction of refractive cylinder: the LASIK group improved from -2.53±1.71 D to -1.28±0.99 D; in the PRK group, from -2.21±2.11 D to -1.10±0.42 D. UCVA also increased in both groups: the LASIK group improved from 0.81±0.68 logMAR (20/130) to 0.29±0.21 logMAR (20/39); in the PRK group, mean UCVA improved from 0.89±0.87 logMAR (20/157) to 0.42±0.35 logMAR (20/53). There was no significant loss of BSCVA. There were no reports of postoperative glare, halos, ghost images, starbursts or monocular diplopia. Journal of Refractive Surgery, April 2006

Women on hormone replacement therapy appear to have an increased risk of refractive regression after LASIK
This retrospective review compared the refractive and visual outcomes of women on hormone replacement therapy (HRT) and oral contraceptives at the time of surgery with women not on hormone treatment. At six months postop, 45 percent of HRT eyes and 75 percent of control eyes had 20/20 vision or better. In addition, 82 percent of eyes from the HRT group and 91 percent of eyes in the control group could see 20/40 or better. Outcomes for women taking oral contraceptive pills did not differ from controls. Journal of Refractive Surgery, April 2006

High axial length appears a risk factor for retinal detachment following PIOL implantation for high myopia
This retrospective study of 522 highly myopic eyes that underwent implantation with phakic intraocular lenses finds a retinal detachment rate of 2.87 percent. The researchers attribute this lower frequency of retinal detachment compared to earlier studies to improvements in surgical procedure and better patient selection. While the researchers did not demonstrate that the correction of high myopia by PIOL implantation plays a role in the eventual occurrence of retinal detachment, they did find that the risk of retinal detachment is higher in eyes with axial length greater than 30.24 mm. Journal of Refractive Surgery, March 2006.

Good outcome following infectious keratitis post-PRK dependent on early diagnosis and aggressive management
This retrospective study of 25,337 PRK procedures performed at six Army and Navy refractive surgery centers (PRK remains the most common form of refractive surgery for military personnel) finds this condition to be very rare, occurring in just four eyes. It's often caused by gram-positive organisms and methicillin-resistant S. aureus. The authors conclude that presentation of corneal infiltrates within one week postop require immediate treatment: aggressive antibiotics, with the addition of gram-positive coverage and removal of the soft contact lens. They recommend smearing, culturing and following closely any infiltrate that is central or paracentral, larger than 2 mm, associated with significant pain or AC reaction or fails to respond rapidly to the above therapy. Two other studies in Ophthalmology offer more advice on treatment: One finds that ulcers exceeding 14 mm2, the presence of hypopyon and identification of Aspergillus predict treatment failure (patients were treated with 5 percent natamycin monotherapy). The second shows in vivo corneal tandem scanning confocal corneal microscopy can establish the diagnosis of Acanthamoeba keratitis rapidly and noninvasively, particularly when conventional microbiology is inconclusive. Ophthalmology, April 2006

Toxic anterior segment syndrome linked to ointment seeping into the anterior chamber after cataract surgery
Researchers from the John Moran Eye Center report on their investigation of eight patients who developed TASS after uneventful phacoemulsification through clear corneal incisions. Pathological examination of the corneas showed variable thinning of the epithelium with edema. The stroma was diffusely thickened and the endothelial cell layer was absent. Evaluation of the explanted IOLs confirmed the presence of an oily substance coating large areas of the anterior and posterior optic surfaces. They determined that tight eye patching following the application of antibiotic/steroid ointment caused the condition. The authors say their findings underscore the importance of appropriate wound construction and integrity during intraocular surgery as well as the risks of eye patching. Therefore, they recommend surgeons be aware of the dynamics of self-healing clear corneal incisions and to anticipate the possibility of intraocular penetration with any postoperative ointment following penetrating procedures. Journal of Cataract and Refractive Surgery, February 2006

Pupil size affects post-LASIK higher-order wavefront aberrations and contrast sensitivity
Ocular wavefront aberrations and contrast sensitivity function were determined in 215 myopic eyes (105 with a photopic pupil diameter of 4 mm or larger and 110 with a photopic pupil diameter smaller than 4 mm) before and one month after LASIK. In eyes with larger photopic pupil diameter, increases in spherical-like aberration dominantly affect contrast sensitivity. In eyes with smaller pupil size, changes in coma-like aberration exert greater influence on visual performance. Investigative Ophthalmology and Visual Science, April 2006

Visual recovery time appears quicker with single-piece hydrophobic acrylic foldable IOL
This prospective study randomized one eye of 40 patients to receive the SA60AT single-piece IOL, and the contralateral eye to receive the MA60AC 3-piece hydrophobic acrylic foldable IOL. Both the single-piece and 3-piece lenses showed a minimum amount of decentration, tilt, anterior capsule contraction and posterior capsule opacification. Although the MA60AC showed significant forward shift and myopic refractive changes after surgery, the SA60AT displayed little axial movement associated with highly stable refraction after surgery. The authors conclude this feature of the SA60AT should facilitate earlier spectacle prescription and quicker visual/social rehabilitation of patients after cataract surgery. Ophthalmology, April 2006

AcrySof ReSTOR IOL can help patients reduce their dependence on glasses
Eight European investigators implanted 127 patients (mean age, 68.4 years) with the AcrySof ReSTOR IOL. Of these patients, 119 had bilateral implantation. At six months postop, binocular (both eyes simultaneously) mean uncorrected distance visual acuity was 0.04 logMAR (20/20). After bilateral implantation, binocular uncorrected near visual acuity at the standard distance of 33 cm was 0.34 logMAR (20/40) or better for 97.5 percent of patients and 0.14 logMAR (20/25) or better for 66.9 percent of patients. Similarly, when tested at best distance, 97.5 percent of patients achieved binocular uncorrected near visual acuity of 0.34 logMAR (20/40) or better and 71.2 percent achieved 0.14 logMAR (20/25) or better. Spectacle independence for distance and near vision was achieved by 88 percent and 84.6 percent, respectively. Glare and halos were reported as severe by 8.5 percent and 4.2 percent of patients, respectively, which the researchers found clinically acceptable. After the first IOL was implanted, 92 percent of patients said they would have the same lens implanted again; after the second implant, that number rose to 95.7 percent. Ophthalmology, April 2006

Toric phakic intraocular lens can correct high to moderate hyperopia combined with astigmatism
This prospective study of 28 patients (47 eyes) found good refractive results in these patients. After a mean follow-up of 11.1 months, 36.2 percent gained one or more lines of best spectacle-corrected visual acuity. The mean postoperative astigmatism at six months was 0.19 D at an axis of 144 degrees. At six months, 76.6 percent of eyes had an uncorrected visual acuity of 20/40 or better. One eye lost two lines of best spectacle-corrected visual acuity. In one eye, the lens position had to be changed due to a large axis misalignment. There were no serious complications, but the authors conclude that the predictability of the refractive results appears lower than those achieved in the correction of myopia and astigmatism with toric Artisan lenses. Journal of Cataract & Refractive Surgery, February 2006

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ISRS/AAO INFORMATION

Journal of Refractive Surgerynow publishes nine times a year and includes online advanced release
The benefit of membership in ISRS/AAO has just increased by three. Three additional issues of the peer-reviewed, official journal of the ISRS/AAO will be published each year. With nine annual editions, you can expect approved manuscripts to be published sooner. Another stride forward is the online publication of accepted and edited manuscripts prior to print publication. The journal also recently expanded its editorial content to include articles dedicated to lens-based refractive surgery, in addition to original research, review and evaluation of refractive and corneal surgical procedures.

Housing and tour information for the 2006 ISRS/AAO meeting now live
To reserve your hotel room, complete the online housing form and return it to United Expo at +90-232-4650086. United Expo is also organizing half day, full day and pre/post meeting tours. To reserve your spot on a tour, complete the online order form and it fax to United Expo at +90 232 465 00 86. Find all the latest information on this year's meeting in Istanbul, including recent updates to the program and faculty listing, from our Web site.

Registration for the 2006 ISRS/AAO meeting is now closed, but you can still register onsite
Don't miss out on this educational (including live surgery demonstrations) and networking opportunity. International Refractive Surgery: Art and Science is scheduled for May 26 to 28 in Istanbul, Turkey.

Will you need a U.S. visitor's visa to attend the Joint Meeting in Las Vegas?
Find out on the Academy's Web site. To assist you in the visa process, the Academy has compiled a complete review of the documentary requirements for international travelers. You can also download a letter of invitation from our site.

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INDUSTRY NEWS

An AAO and ASCRS sponsored study: refractive procedures flat, cataract procedures down
The number of estimated cataract procedures fell by 60,000 in 2005, while the number of refractive procedures remained unchanged, according to results from the annual survey of members of the American Society of Cataract and Refractive Surgery. The estimated annual volume of cataract surgery was 2.79 million procedures, according to the respondents, down from 2.85 million in 2004. The estimated volume of refractive procedures, such as photorefractive keratectomy, LASIK or LASEK, also declined to 928,737 procedures in 2005. During 2004, the volume was 948,266. The number of surgeons performing bimanual microincision cataract surgery increased from 3.3 percent to 4.4 percent in 2005. Of those performing the procedure in 2005, half do so in 10 percent of their cases, while 26.5 percent perform bimanual phaco only. In 2004, 62 percent of the surgeons performing the procedure did so on 10 percent of their patients, while 31 percent performed bimanual phaco only.

U.S jury awards LASIK patient $3 million
An eight-member jury in Minnesota determined that Northern Refractive Surgery failed to inform the 34-year-old patient about the risks involved in LASIK surgery or about alternatives to the LASIK procedure. The patient, who suffered from visual disturbances at night, said his physician failed to properly screen him from LASIK because of his larger-than-average pupils.

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FEATURE

Transitioning to IntraLase: 12 Pearls for Early Success with IntraLase

Perry S. Binder, MD

The single best thing a surgeon starting out with IntraLase can do is spend a day with an experienced IntraLase surgeon. Such a day is worth its weight in gold because there is a great deal that can only be learned from an experienced surgeon.

Next, prepare the staff well before the laser arrives. Tell them why the technology has been acquired and its importance to the practice and the patients. Make sure every staff member knows that you believe the technology is genuinely better for patients and why you believe it. Credibility with patients demands that everyone believes in what the practice is doing and unambiguously conveys that belief to patients.

I think it is vital to make the decision process as straightforward as possible for patients. Offering a choice between IntraLase at one price and traditional microkeratome LASIK at a lower price will only confuse patients. When you convert to IntraLase, all of your LASIK patients should be IntraLase patients (with the exception of previous refractive surgery cases such as radial keratotomy).

Laser Settings
The IntraLase clinical application specialist who installs the laser will suggest laser settings for the first cases. But every laser is slightly different, and surgeons have to modify those setting based their own clinical findings. In most cases, I would suggest following the company guidance for approximately the first 10 to 20 eyes. After 15 to 20 eyes, the laser should be adjusted to a point where only fine tuning is needed in the future.

When starting to use the Intralase, I would strongly encourage surgeons to measure and record achieved flap thickness. Other important data include the ease of lifting the flap, the quality of the gas bubble layer and how long it takes for the bubbles to clear. This information will guide the subsequent parameter adjustment of the laser.
 
Changing the Patient Flow
The femtosecond laser creates gas bubbles in the interface, and some surgeons prefer these gas bubbles clear before the flap is lifted. With the new 60 kHz engine, the bubbles dissipate in a minute or less, so the surgeon can create flaps in both eyes, move the patient under the excimer laser and proceed to treat.

With the 15-kHz and 30-kHz engines, the gas bubbles take longer to clear. To minimize waiting between patients, our strategy has been to create flaps in both eyes of patient one, instill a drop of diclofenac in each eye, then have the patient wait with eyes closed. We would then bring in patient two and do the same thing. At that point, if the interface was clear in patient one, we would perform the excimer treatment, after which we would create flaps in patient three, and then perform the excimer procedure on patient two, and so on.

Flap Lifting
A device to lift the flap is the only instrument needed to work with the IntraLase. There are three good choices. The first is the Seibel flap elevator, a triangular instrument with sharp point. The device is simple to use but its sharp point is both helpful and a potential source of trouble. The second option is a Slade flap spatula (Stephens Instruments), a flat, slightly curved spatula – an instrument I sometimes use. The third option is an instrument I developed for Katena (I have no financial interest) called an IntraLase flap elevator. It is essentially a Slade spatula, but the tip is about one-third the width of the Slade spatula’s. Because the tip is small and smooth, it gets into the interface relatively easily.

A new skill IntraLase surgeons have to develop is how to enter the interface. I use a Sinsky hook to score the wound for one clock hour (for a superior flap on a right eye, I enter at 9 o’clock). I use the Sinsky hook only to cut straight down along the gutter to the interface for that one hour. Then I enter and get under the flap with a spatula, after which the lamellar dissection can be made using one of several techniques. Unlike a microkeratome flap, there are small adhesions with the IntraLase flap, so there is a small learning curve related to lifting these flaps.

Avoiding Common Mistakes
Don’t begin with tough cases. The 490-micron cornea, the post-radial keratotomy eye, and the prior buttonhole are all good candidates for correction that starts with an IntraLase flap. But correct those eyes after you have gained some experience with the technology.

Don’t try to make very thin flaps before you have learned what your laser can do. Until you know from experience the capabilities and settings for your particular IntraLase, stick with 110-micron or 120-micron flaps. Don’t attempt 90-micron or 100-micron flaps at the outset. 

The most common error that I see among IntraLase surgeons is failure to center the fixation ring on the eye. If the laser is docked without the ring being centered, the laser software must be used for centration. This process can also require a decrease in the attempted flap diameter by the software. This process also slows the procedure and adds to the time the eye is under suction, which can be uncomfortable for the patient. Using the laser’s joystick to center risks breaking suction. It is best to get centration right immediately.

Another common error concerns the applanation cone. Some surgeons don’t pay attention to the diameter of the applanated portion of the cornea. If the area of applanation doesn’t slightly exceed the diameter of the predicted cut, the laser won’t focus properly at the edge of the cut. The result may be an incomplete cut or a flap that is difficult or impossible to lift.

Finally, if something unusual is happening, stop the procedure, make the necessary adjustment, and start back up. For instance, if the laser is going outside the applanated area, stop (let up on the foot pedal), fix the problem and restart. Similarly with a gas escape through an injury to the cornea: stop, fix the problem and then continue.   

Know When You’re Doing Well
How do you know if the procedure has gone as expected? One sign is that as soon as you take suction off the gas bubbles disappear from the interface and the interface becomes semi-transparent almost immediately. That’s a very good sign. Easy flap lifts that can be performed in one motion without having to go in and out several times is another good sign. Flap thickness predictability is also a good indicator. If the standard deviation of flap thicknesses is in a smaller range than with your mechanical microkeratome (usually one-third to one-half of what it used to be), that is a good sign.

Twelve Pearls for Early Success with IntraLase

1. Spend a day with an experienced IntraLase user.
2. Prepare the staff carefully. Share your enthusiasm for and belief in the technology.
3. Convert to 100 percent IntraLase as quickly as possible. Don’t confuse patients by letting them chose between IntraLase and mechanical microkeratome.
4. Record laser data from early cases to modify subsequent laser parameters.
5. Work on flap lifting technique. It is not the same as with a mechanical microkeratome.
6. Start out with routine corrections in normal, average eyes. Move on to more difficult eyes after experience is gained.
7. Don’t attempt thin (90- micron or 100-micron) flaps until the laser has been adjusted and you know its capabilities.
8. Center the fixation carefully ring on the eye. Relying on the laser for centration increases time under suction and reduces the planned flap diameter.
9. Take care with the applanation cone. Be sure the cornea is applanated beyond the edge of the cut.
10. If something seems to be going wrong, stop the laser, fix the problem and then restart.
11. You are doing well when:
    *Interface gas bubbles dissipate readily and interface becomes semi-transparent almost immediately
    *Flaps are easily lifted
    *Flaps thickness standard deviation (SD) is one-third to one-half of microkeratome flap thickness SDs

Locating the Laser
Surgeons who own a Visx (AMO), Bausch & Lomb, or Nidek excimer laser can place the IntraLase immediately adjacent to their excimer laser, so the same patient bed can be used for both lasers. After the IntraLase flaps have been made, the bed can be rotated under the excimer head for the refractive cut.

With other lasers, including the WaveLight Allegretto and the Alcon LADARVision, the IntraLase can be in the same room but there must be a second bed in the room, and space may be an issue. Another option is to have the IntraLase in a separate room away from the excimer laser.

The one caution is that the IntraLase can be sensitive to vibration, so it may help to locate it away from machine rooms and other sources of vibration.

An Offsite IntraLase?
An option that is available in some locations is to use the IntraLase at a laser center. After their flaps have been made at the IntraLase site, patients can come to your excimer site at their convenience. Since a small epithelial defect is created, the patient will need antibiotic prophylaxis for several days after the flaps have been cut. But once the flaps are made, there is considerable leeway in scheduling the excimer procedure.

While this may not be the ideal way to proceed with aroutine LASIK procedure, it can be an excellent way to proceed in special cases, such as the patient who receives a phakic IOL and then needs a subsequent LASIK “touch-up” after the procedure. In this case, the flap can be made several weeks before the intraocular surgery (and simply left in place). Four to six weeks after the intraocular surgery, a laser procedure to correct any residual refractive error can be performed. There’s no need to wait three to six  months to be sure that pressure from the suction ring won’t cause problems with the cataract wound.

Perry S. Binder, MD,  founding partner of the Gordon Binder Weiss Vision Institute in San Diego, Calif., USA.

The Ocular Surface is a peer-reviewed journal with review articles on medical and surgical topics related to the anterior eye. Visit the Ocular Surface Web site for a free sample copy and special offer for ISRS/AAO members.

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