Advancement of specialty hinges on worldwide exchange of information

Our report on this topic and more from the joint meeting of Ocular Surgery News and the Italian Society of Ophthalmology is found below.

NAPLES, Italy — Ophthalmology thrives in the era of globalization, cooperation, exchange and reciprocal learning, according to H. Dunbar Hoskins, MD.

“Information travels almost instantaneously, and ophthalmology all round the world is up to speed. At its best level, it is equivalent throughout the continents,” he said in an interview at the joint meeting of Ocular Surgery News and the Italian Society of Ophthalmology, where he received the 2008 SOI Honorary Award in Ophthalmology.

The United States may have been in the forefront 25 years ago, but “today there are new things evolving in Europe and Asia as well as in the U.S., and we all learn from each other,” he said.

This global cooperation is critical to the progress of science and will generate the best possible care for patients, Dr. Hoskins said.

The American Academy of Ophthalmology is increasingly involving people from other countries in the Academy’s committees, activities and educational programs. In turn, the AAO is invited to participate in joint meetings in Europe and Asia.

In addition, the Internet is an invaluable channel for instantaneous communication beyond borders.

To fully exploit the potentials of the Internet, the AAO has created the Ophthalmic News and Education (ONE) network.

“Our network is open to all the news that the scientific community, the industry and the media want to share, without too much filter. It will publish journal abstracts, give full text access to the major journals of ophthalmology, and provide videos of all surgical techniques and structured educational programs with self-assessment tests,” Dr. Hoskins explained.

The ONE is currently available to U.S. users, but will be extended to all countries in 2009 through national and international societies. It will also be available for free in developing countries.

It will be “a place where the world of ophthalmology can collaborate to provide the best possible and most updated information. It is beginning now, but in 10 years time it will be an incredible resource, where all of us will be able to find instantaneously whatever is needed to keep our practice updated,” Dr. Hoskins said.

These items appeared originally as daily coverage from the meeting on OSNSuperSite.com. Look for more in-depth coverage of these and other topics in upcoming issues of Ocular Surgery News.

IOL can be sutured to iris in patients with inadequate capsular support

In patients with inadequate capsular support, the IOL can be implanted in the anterior chamber, suturing the haptics to the peripheral iris, according to a lecturer.

In the Gian Battista Bietti Medal Lecture, Walter J. Stark, MD, said, “This technique can be accomplished through a 3.5-mm incision. The pupil is constricted with acetylcholine, and the IOL is folded and inserted through the corneal wound, placing the haptics within the sulcus and positioning the optic above the plane of the iris.”

In the technique, a Barraquer sweep is passed through the paracentesis and placed beneath the optic as the lens is unfolding, he said. Additional viscoelastic is injected into the anterior chamber to push the iris posteriorly against the haptics, while the optic is lifted by the Barraquer sweep.

The haptics are tied to the peripheral iris using a modified McCannel-type iris-fixation technique, with a needle and a 10-0 polypropylene suture, Dr. Stark said. Then, the optic is placed posterior to the iris.

“This technique permits secondary IOL insertion in aphakic patients who are contact lens intolerant, facilitates the management of IOL problems after surgery that require IOL exchange and allows the surgeon to treat patients who develop loss of capsule support at the time of cataract surgery,” Dr. Stark said.

Toric IOL has good preliminary results

Preliminary results with the toric Artiflex IOL from Ophtec seem to indicate that this lens is ideal for correcting both sphere and cylinder, according to one speaker.

The first two lenses were implanted in August 2006, and a European study involving seven centers has been ongoing since September.

In presenting his personal first results, Camille Budo, MD, showed that at 6 months the lens is safe in terms of endothelial preservation. The mean endothelial cell count remained nearly unchanged after the procedure. Both myopia and astigmatism were significantly reduced.

The surgical technique is basically the same as for the spherical iris-claw models, and like its predecessors, this lens has almost no complications, “provided that implantation is performed by an experienced surgeon and that the correct alignment with the astigmatic axis is calculated,” Dr. Budo said.

Endophthalmitis prophylaxis crucial after intravitreal injection, surgeon says

Because of the increasing number of intravitreal injections administered as therapy for various posterior segment diseases, physicians could be facing an emerging epidemic of endophthalmitis if the necessary precautions are not taken, according to one surgeon.

Terrence P. O’Brien

Intravitreal medications often require repeated administration, sometimes as often as once a month. “Patients receive six to 12 injections per year, and potentially, each one of them poses a threat for infection,” Terrence P. O’Brien, MD, said.

Although the mechanisms of infection are not completely understood, various organisms are normally present on the conjunctival surface, and passing the needle through the conjunctiva and sclera via the pars plana approach may present an opportunity for these organisms to gain entry into the eye. Also, the transient decrease in pressure caused by the needle entering the eye may pull the organisms from the tear film and ocular surface inward through the sclerotomy, he said.

“Typically, the size of the needle is 27-gauge or 30-gauge, but this is still large enough to create a portal for the entry of organisms,” Dr. O’Brien said.

An additional problem is that intravitreal injections are often administered in an office setting rather than in a surgical theater, where the level of antisepsis is higher and protocols to prevent infections are better defined and stricter.

A panel of experts met recently in the United States to try and provide recommendations on this particular treatment modality, but there was no consensus on a universal routine, Dr. O’ Brien said.

“There is a lot of controversy about prevention and pre-injection preparation. Gloves were recognized by everyone to be beneficial, and the use of a sterile lid speculum was recommended. However, there was incomplete agreement about the need for draping the eyelid and lashes,” he said.

There was consensus on the use of an antiseptic, namely 10% povidone iodine, for the eyelid and lashes and a drop of 5% povidone iodine placed directly onto the ocular surface.

Antibiotics were another controversial topic, he said, and different opinions were expressed concerning the type, timing and frequency of antibiotic administration before and after the treatment.

The majority said a broad spectrum antibacterial agent such as a fluoroquinolone administered in four consecutive topical doses before the injection and four to six times a day for the first 5 to 7 days after the treatment may be sufficient to protect against the most likely organisms.

Knowledge of corneal topography essential for LASIK screening

Surgeons should have a good working knowledge of corneal topography and topographers to help them effectively screen patients for LASIK contraindications such as forme fruste keratoconus, according to a surgeon.

Corneal topography is a mature diagnostic tool that can predict within a narrow margin of error the risk for ectasia after LASIK, Stephen D. Klyce, PhD, said.

Educated use and the choice of the most suitable equipment are essential to meet the standards of care in screening patients and to avoid LASIK disasters, Dr. Klyce said.

As corneal topographers have evolved over the years, some have developed complex displays with a lot of data. While an expert might understand how to integrate all of this information, most of it is unnecessary in routine clinical use.

“A topographer that adopts a fixed-interval and contrasting-color scale with a few added familiar measures like pupil diameter and simulated keratometry should be sufficient,” Dr. Klyce said.

It is useful to have a routine benchmark with which to occasionally test a corneal topographer to ensure calibration is being maintained, he said.

In reality, corneal topography actually measures the shape of the tear film, he noted. If the patient has dry eyes or has been given drops before examination, irregularities in the topography will be recorded. They are temporary artifacts and do not represent the true shape of the cornea. To avoid misreadings, the patient should be asked to blink several times before capturing the images, Dr. Klyce recommended. If the mires remain irregular, the presence of a corneal pathology should be considered.

A normal cornea has smooth contours and centrally uniform power and is flatter in the periphery, particularly toward the nasal side. Simulated keratometry readings should be about 42.75 D. A good rule of thumb would be to consider keratometry readings less than 38 D or greater than 47.5 D abnormal. Normal corneas may also present the characteristic bow-tie pattern of corneal cylinder.

Contact lens warping can masquerade as keratoconus by causing inferior or superior steepening in corneas that have with-the-rule astigmatism. Discontinuation of contact lens wear and re-examination with corneal topography 2 to 3 weeks later should allow the clinician to test for refractive stability and differentiate between true keratoconus and pseudo-keratoconus due to contact lens warping.

“With true keratoconus, the area of steepening will generally increase, while with contact lens warpage, a symmetrical bow-tie pattern will often re-emerge,” Dr. Klyce explained.

IOP fluctuation is a critical but often underestimated glaucoma parameter

IOP fluctuation in glaucoma patients is an important parameter that is often neglected or underestimated, according to a specialist.

“Circadian fluctuations occur in normal and glaucomatous eyes, but a great deal remains unknown due to a lack of noninvasive methods of continuous measurement of IOP in the patient’s own environment,” Sanjay Asrani, MD, said.

“We measure our patients’ IOP for a total of about 5 to 6 seconds in the whole year because we do three or four visits during which we take a measurement for 1 to 2 seconds,” he said. “This is a very low amount of data. That doesn’t reflect the changes that occur at different times of the day and night, and in relation to the patients’ activities, stress and emotional changes.”

IOP changes just like blood sugar changes, he said, and the availability of glucose monitoring systems has shown to be important in the management of diabetes.

“Of course it would be great to have an eye pressure monitoring system. Experimental devices, like pressure-monitoring contact lenses and implantable microchips, are currently under investigation, and we hope that in a few years time they’ll become available,” he said.

In the meantime, Dr. Asrani said, practitioners should measure long-term IOP variations at multiple office visits during daytime clinic hours over a period of several months or take “mini-curves” of diurnal IOP fluctuations.

Laser welding may be effective for capsule repair

A new laser welding technique may help repair lens capsule trauma that occurs during standard IOL implantation and in providing closure of the capsulorrhexis in lens-refilling procedures, according to an international team of surgeons.

Experiments were carried out in enucleated porcine eyes. A patch of donor capsular tissue of a few square millimeters was stained with a solution of indocyanine green, applied on a capsulorrhexis and then sealed to the capsule surface by a series of laser welding spots delivered by the optical fiber of a diode laser.

“Following laser welding, the patches showed a very good resistance to mechanical traction and were effective in sealing the capsular content of heavy silicone oil,” Luca Menabuoni, MD, said.

Optimum laser irradiation parameters were identified to minimize heat damage and alterations to the capsule morphology, as confirmed by histological examination.

The same technique was previously used for sealing the corneal wound in a series including 20 eyes of 20 patients undergoing phacoemulsification surgery or extracapsular cataract extraction. The diode laser-assisted procedure produced a tight sealing, with no collateral effects.

The study on laser welding applications involves the Ophthalmology Department of Prato Hospital in Italy, Bascom Palmer Eye Institute in Miami and the National Research Council of Florence, Italy.

Long-term results assuage fears over endothelial cell loss in EK

Francis W. Price

Outcomes of a large series of endothelial keratoplasty procedures, both Descemet’s stripping with endothelial keratoplasty and Descemet’s stripping automated endothelial keratoplasty, with a follow-up of more than 3 years, provide reassuring endothelial cell count data, rejection rate and, hopefully, long-term graft survival, according to a speaker.

“Endothelial keratoplasty [EK] has been rapidly adopted,” Francis W. Price Jr., MD, said. “However, concerns have been raised by the somewhat higher rate of endothelial cell loss compared to that reported in recent penetrating keratoplasty series.”

EK requires more donor tissue manipulation than PK, both in the stage of preparation and graft insertion, and this inevitably has an impact on early cell loss.

“We have now performed over 1,000 EK procedures and have experienced different and increasingly better techniques. Our outcomes show that the type and width of incision and the devices used for insertion have a significant influence on early endothelial cell loss,” Dr. Price said.

Several of the newer forceps designs can help reduce tissue damage when the donor button is folded for insertion. Newer techniques, such as Busin’s insertion through a funnel glide, are also less traumatic and allow for a gentler placement of the graft into the recipient eye through a smaller incision.

“Although the mean 6-month cell loss in our DSEK series was higher than in our own and other recent PK series, subsequent cell loss at 1, 2 and 3 years has been minimal, and the mean cell loss at 3 years is well within the range seen after PK,” Dr. Price said. These findings, he noted, may help alleviate concerns about long-term EK graft survival.

“Of course, graft rejection is a concern after EK, just as it is after standard PK. However, since wound healing is not a significant concern after EK, many surgeons leave EK patients on low-dose topical steroids indefinitely, and this may help reduce the risk of graft rejection,” he said.

MICS, multifocal IOL achieve good vision, study shows

Microincision cataract surgery with implantation of the Acri.Tec multifocal Acri.Lisa 366D IOL seems to meet the requirements of today’s active patients, according to one speaker.

Jorge L. Aliò, MD, PhD, said he used this lens in 69 eyes of 52 patients with a mean age of 59 years and a mean spherical equivalent of +1.22 ± 3.62 D. Visual and optical outcomes were evaluated 6 months postoperatively by measuring refraction, binocular uncorrected and corrected visual acuity for far and near (40 cm), intraocular aberrations, Strehl ratio and modulation transfer function.

The postoperative spherical equivalent was +0.39 ± 0.51 D, with 70% of the eyes within ±0.5 D and 86% of the eyes within ±1 D. Mean visual acuity at distance was 20/25 uncorrected and slightly less than 20/20 best corrected. More than 90% of the patients were able to read J1.

“The Acri.Lisa offers clinically outstanding efficacy, predictability, safety and excellent visual results at distance and near,” Dr. Alió said. “Excellent values were also found for optical aberrations, Strehl ratio and [modulation transfer function].”

Dermatological treatment may have application as dry eye therapy

A new alternative treatment using intense pulse light and broadband light is showing promise in treating dry eye syndrome from non-autoimmune etiology, according to a study.

Intense pulse light and broadband light are more commonly used in dermatology to treat skin conditions such as rosacea.

“We started administering this treatment in our aesthetic clinic in Memphis and found that our patients had some beneficial collateral effects on dry eye symptoms,” Rolando Toyos, MD, said.

Since then, he started investigating the rationale for application of the same light treatment for dry eye.

“The treatment improves the function of meibomian gland function, which is notoriously correlated with the formation of the tear film’s lipid layer,” Dr. Toyos said.

Patients receive treatment in four selected facial areas. Tear break-up time and Schirmer’s tests are performed during the first visit to establish baseline values before first treatment, before all subsequent treatments, and at 1, 3 and 6 months after completion of the treatment to assess the efficacy on dry eye symptoms. An average of four to five monthly treatments are usually necessary to achieve stable results, he said.

“In our patients, we found an average increase of [tear break-up time] of 47% and 33% with [intense pulse light] and [broadband light], respectively, and an increase of 60% with [intense pulse light] and 84% with [broadband light] for Schirmer’s test,” Dr. Toyos said.

A note from the editors:

To facilitate bringing news to readers rapidly, for OSN SuperSite articles and meeting wrap-up articles, OSN departs from its editorial policy and typically does not send these items out for source corrections.