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Complications associated with trabeculectomy have prompted a search for better alternatives. Practice pattern data from recent years show growing usage of tube implants. Results of the multicenter, randomized Tube vs. Trabeculectomy study offer validation for this trend.

Canaloplasty with tensioning suture placement is an FDA-approved technique for the surgical management of open-angle glaucoma. This nonpenetrating procedure obviates the need for a bleb and has been associated with good IOP control after 2 years of follow-up. The accumulating data and a successful training program are contributing to increasing interest.

Implantation of a glaucoma drainage device made entirely from medical-grade gold (SOLX GMS Plus Gold Shunt, SOLX Inc.) is a viable surgical option for primary open-angle glaucoma (POAG).

Implantation of a trabecular bypass microstent (iStent GTS-100 Trabecular Micro-Bypass Stent, Glaukos Corp.) effectively lowered IOP and dramatically decreased anti-glaucoma medication use among 48 subjects in a prospective, 24-month, multicenter evaluation. The stent bypasses the blocked trabecular meshwork to allow aqueous fluid to move into the Schlemm's canal area and then out through collector channels.

A miniature shunt (Ex-Press, Optonol) is as effective as standard trabeculectomy procedures in the lowering of IOP in patients with glaucoma, according to a retrospective review. The advantages of implementation of the device over standard trabeculectomy include a greater decrease in the postoperative medications taken by patients, lower levels of hypotony occurrence, and a predictable, even flow reduction of aqueous fluid from the subconjunctival space.

A modified version of a commercially available high-definition optical coherence tomography (OCT) device, adapted for imaging the anterior chamber angle, was able to provide higher-resolution images than current OCT devices and help investigators identify a new anatomic landmark. If this instrument is developed commercially, it could become a new gold standard for diagnosis of angle-closure glaucoma.

A new perimetry device (Heidelberg Edge Perimeter, Heidelberg Engineering) shows to be very useful in the precise evaluation of patients with glaucoma and suspect glaucoma. This unique instrument may very well replace standard automated perimetry devices.

Although edged out by prostaglandin analogs as the preferred first-line medication for glaucoma therapy, beta-blockers, including a once-a-day formulation of timolol maleate (Istalol, ISTA Pharmaceuticals) remain an acceptable choice for first-line or additive therapy, according to one ophthalmologist. Timolol generally is well tolerated and may be a cost-effective choice for some patients.

Initial results from the Glaucoma Adherence and Persistence Study confirmed poor patient adherence with prescribed glaucoma medication therapy and identified lack of motivating concern and a doctor-dependent learning style as independent predictors of poor adherence. New analyses provide insight on the features of patients who possess these characteristics and patterns of physician communication associated with adherence.

Investigators using a non-contact applanation tonometer (Ocular Response Analyzer [ORA], Reichert Inc.) have made finds pertaining to the importance of corneal hysteresis, the role of ocular biomechanical properties in the pathophysiology of glaucoma, and differences in these properties between African Americans and Caucasians.

A new formulation of travoprost (Travatan Z, Alcon Laboratories) containing an ionic-buffered preservative (sofZia), and the older formulation (Travatan), preserved with benzalkonium chloride (BAK), had similar IOP-lowering effects in a group of patients who began treatment with the original drop then switched to the newer drug. The ionic-buffered agent is intended to be less toxic to the ocular surface than BAK, which could be significant in long-term glaucoma therapy.

Results of a retrospective chart review including 101 consecutive eyes that underwent endoscopic cyclophotocoagulation (ECP) combined with phacoemulsification and IOL implantation document the safety of this procedure for lowering IOP. A subgroup analysis suggests that ECP may have a unique application in eyes with chronic angle-closure glaucoma and plateau iris.

Outcomes of a 5-year study, initiated when the first prostaglandin analog became available, showed that latanoprost (Xalatan, Pfizer) does not increase the frequency of corneal erosions during long-term glaucoma treatment when compared with other forms of pressure-lowering medication.

A study conducted at the University of Dresden confirms the short-term effectiveness of implantation of a proprietary shunt (Ahmed, New World Medical) in patients with refractory glaucoma. Patients in this 1-year study experienced statistically significant declines in IOP and number of medications, and best-corrected visual acuity (BCVA) remained stable in approximately half of the group. The cumulative probability of success after 1 year of follow-up was 83.3%.

The fixed combination of brimonidine tartrate 0.2% and timolol maleate 0.5% (Combigan, Allergan) is an effective and well-tolerated substitute treatment for patients whose IOP remains uncontrolled under prostaglandin analog monotherapy or any other fixed combination of hypotensive agents, according to a poster presentation made at the World Ophthalmology Congress.

Glaucoma screenings can help identify people who may have the disease to encourage them to receive care. Ophthalmologists must stress to participants the importance of seeking that care and adhering to any subsequently prescribed therapy. Vision loss from glaucoma occurs with the death of the retinal ganglia cells that travel from the optic nerve to the brain. Therefore, a current goal is to identify sick cells that try to "rescue" them by lowering IOP. For the future, however, the hope is to be able to regenerate cells that have been sickened by the disease.

Research supports that 24-hour IOP control is critical to minimizing glaucoma progression. Practitioners are encouraged to review the choices for primary and adjunctive medical therapy based on the ability to control pressures during both the day and nocturnal periods.

In a retrospective, longitudinal cohort analysis of 14,491 Medicare beneficiaries who underwent one of the three incisional glaucoma surgeries between 1994 and 2003, those who underwent glaucoma drainage implant surgery were more likely to have severe complications, low vision, and progression to blindness than those who had a trabeculectomy. The results run counter to an ongoing randomized controlled trial of the procedures.

As imaging continues to move in the direction of digital technology, one such vision platform (3-D HD, TrueVision) takes a stereoscopic view of a surgical microscope, converts it to a three-dimensional, high-definition digital image, and displays it on a projection screen. The technology, according to surgeons who have used it, affords a defined depth of field, offers the ability to play back and share images, and results in less neck and back strain.

Despite the efficacy of the prostaglandins as first-line agents for reducing IOP, many patients require one or more additional agents to reach treatment goals. A recent clinical trial compared two agents, brinzolamide (Azopt, Alcon Laboratories) and brimonidine (Alphagan P, Allergan), as adjunctive therapy and offers perspectives on the best choice for addition to a prostaglandin.

Use of an oscillation device (NeoSoniX handpiece, Alcon Laboratories) results in a shorter phacoemulsification time compared with the time in cases in which a conventional handpiece was used. This difference may result in less phaco energy use in the eye, less trauma during surgery, more rapid visual rehabilitation postoperatively, and perhaps less loss of endothelial cells.

A prospective evaluation of the first 50 cases of coaxial microincision cataract surgery performed with a vision enhancement system (Stellaris, Bausch & Lomb) shows that the platform facilitates adoption of this new surgical technique and allows surgery to be performed with higher levels of vacuum, less dependence on ultrasound, and excellent anterior chamber stability.

High- and low-frequency energy in porcine and human eyes displayed on an oscilloscope showed that the energy levels behave differently in the eye during phacoemulsification.

Two pediatric ophthalmologists at St. Louis Children's Hospital, Lawrence Tychsen, MD, and Gregg Lueder, MD, are trying to warn the public about what they call a "21st-century snake oil" scam, according to a prepared statement issued by the hospital.

There may be a great unease among ophthalmologists when it comes to the current relationship between industry and professional meetings including conflict of interest among speakers at ophthalmology meetings, disclosures of such conflicts by speakers, and concern about the "integrity" of these meetings.

Anti-angiogenic therapy for aggressive posterior retinopathy of prematurity (ROP) may be a feasible therapy for the children with this form of ROP, which develops in profoundly immature neonates. The BLOCK-ROP study, which will begin in the second quarter of 2008, will add to the limited knowledge of the safety and efficacy of an anti-vascular endothelial growth factor drug in treating posterior ROP.

A study in the August issue of the Journal of the American Association for Pediatric Ophthalmology and Strabismus reports that daily treatment with a medication called pirenzepine can slow the rate of progressive myopia.

Researchers have identified a link between toll-like receptor 3, a protein that alerts the body's immune system to infections and, the dry form of age-related macular degeneration.

An innovative ophthalmic lens support system available for licensing has been developed to stabilize the lens before or during cataract surgery, preventing the movement of lens fragments into the back of the eye, according to a market watch report in The Wall Street Journal.

It has just been discovered by researchers at Brigham Young University and Weill Medical College of Cornell University that two processes in the retina, which in combination contribute to age-related macular degeneration, can be disrupted by antioxidants.