News

A modified latex bead rat model has proven to be valid for measuring retinal ganglion cell loss in high-pressure glaucoma.

Intravitreal injection of up to 4 mg of a fusion protein that is an anti-vascular endothelial growth factor agent (VEGF Trap-Eye, Regeneron Pharmaceuticals Inc.) is well tolerated and yields no evidence of ocular inflammation. The agent appears to produce rapid and durable clinical increases in best-corrected visual acuity, along with improvements in anatomic features, in patients with neovascular (wet) age-related macular degeneration.

The 6-month interim results from the Verteporfin Intravitreal Triamcinolone Acetonide Study indicate that the combination of photodynamic therapy with verteporfin and either pegaptanib (Macugen, OSI/Eyetech and Pfizer Ophthalmics) or triamcinolone acetonide (Kenalog, Bristol-Myers Squibb) in two different doses resulted in no differences among the groups on several key measures.

Selective VEGF inhibition appeared to produce improvements in vision and macular edema in patients with central retinal vein occlusion in a recent study. In this multicenter, randomized trial, patients with macular edema secondary to CRVO received five intravitreal injections of pegaptanib sodium over a 24-week period.

A new signaling pathway in the trabecular meshwork is involved in glaucomatous ocular hypertension, believes the research team that discovered it. Altered Wnt signaling may be responsible for pathogenic elevated IOP.

A novel retinal imaging tool combining confocal scanning laser ophthalmoscopy (cSLO) with high-resolution spectral-domain optical coherence tomography (SD-OCT) allows for the first time simultaneous imaging with cSLO (including angiography and autofluorescence) and SD-OCT.

Bevacizumab rescue therapy administered following treatment with pegaptanib (Macugen, OSI/Eyetech and Pfizer Ophthalmics) resulted in minimal improvement, said William R. Freeman, MD, at the Association for Research in Vision and Ophthalmology annual meeting. While primary bevacizumab (Avastin, Genentech) therapy for choroidal neovascularization (CNV) in age-related macular degeneration (AMD) resulted in 2 to 3 ETDRS lines of improvement, which is similar to the improvement seen with ranibizumab (Lucentis, Genentech).

This year, the Association for Research in Vision and Ophthalmology annual meeting focused on the aging eye. With reference to new treatment possibilities, researchers presented information about novel therapies for age-related macular degeneration, glaucoma, and other age-associated ocular conditions, as well as investigations of current treatments.

The rehabilitation of the contracted anophthalmic socket may be challenging for the surgeon. In order to retain and support an ocular prosthesis, there must be adequate orbital volume, mucosal lining of the fornices and the fundus of the socket, a properly sized prosthesis, and adequate support from the upper and lower eyelids. David E. Holck, MD, reviews the pathophysiology of the contracted socket and possible surgical options that can be undertaken in collaboration with an ocularist.

A new offset system (Torsion Error Detection, Nidek) for alignment control measures the distance between the line of sight and the visual axis as well as the difference between photopic and mesopic fixation images. The amount of translation needed to match these images can be an indicator of poor fixation. The offset system allows detection and definition of line of sight and visual axis positions.

The American Society of Cataract and Refractive Surgery's Refractive Surgery Survey reached the 10-year mark in 2006. The results show an increase in epi-LASIK, advanced surface ablation, and wavefront-guided procedures and continued surprises regarding some standard-of-care issues.

Mixing and matching multifocal IOLs appears to be a safe and effective approach, according to a study of two lenses from the same manufacturer (Tecnis and ReZoom, Advanced Medical Optics). The surgeon who conducted the research provides pearls for using this technique.

A new corneal template (OptiPoint, Refractec) for conductive keratoplasty ([CK]; ViewPoint CK, Refractec) was designed to address existing challenges of the procedure to make CK easier to learn and perform while improving the consistency of the results. Those benefits along with good refractive and vision outcomes have been achieved in clinical use.

A prospective, randomized, single-site, multi-surgeon study of two platforms for wavefront-guided LASIK for the treatment of myopia underlines the excellent performance of advanced laser technology and ablation algorithms.

Initial findings from a prospective randomized study comparing a conventional ablation (LADAR4000, Alcon Laboratories) and wavefront-optimized technique (Allegretto, WaveLight) for hyperopic LASIK favor the latter for better predictability and vision outcomes. The results are considered excellent for both, however. Initial results from clinical experience with wavefront-guided hyperopic LASIK (CustomCornea, Alcon Laboratories) are also presented.

Iris registration with compensation for cyclorotation and centroid pupil shift seems to be essential for further improvement of refractive outcome and patient satisfaction. Ignoring the pupil centroid shift can lead to sub-optimal results in wavefront-driven refractive surgery.

The unique, three-dimensional configuration of a dual accommodating IOL (Synchrony, Visiogen) mandates careful surgical technique to ensure optimal implantation and postoperative results. Based on experience in more than 100 eyes, Victor Bohorquez, MD, outlines some of the important considerations.

In eyes undergoing LASIK, use of one proprietary microkeratome (Zyoptix XP, Bausch & Lomb) yields a low rate of complications, good uncorrected visual acuity, and refractive precision in a review by two surgeons in the same practice.

A new offset system (Torsion Error Detection, Nidek) for alignment control measures the distance between the line of sight and the visual axis as well as the difference between photopic and mesopic fixation images. The amount of translation needed to match these images can be an indicator of poor fixation. The offset system allows detection and definition of line of sight and visual axis positions.

A femtosecond laser (IntraLase, Advanced Medical Optics) and microkeratome (M2, Moria) differ when it comes to changes in the flap and stromal bed that develop between primary LASIK and enhancement procedures. A greater increase in flap thickness at the time of enhancement after myopic LASIK might be the result of epithelial hyperplasia, according to Ronald Krueger, MD, speaking at the annual meeting of the American Society of Cataract and Refractive Surgery.

A new excimer laser platform (Technolas 100, Bausch & Lomb) is equipped with eye-tracking technology for static and dynamic eye alignment and can be integrated with online optical coherence pachymetry (OCP). Clinical experience demonstrates the performance of OCP and the value of static and dynamic rotational eye-tracking for improving LASIK outcomes.

Tracking of dynamic rotational eye movements during LASIK is especially important for obtaining good ablation results, considering that 29% of eyes can rotate 5° or more when the patients shift from the sitting to the supine position.

When a prospective, randomized study was undertaken to investigate the outcomes of "mixing and matching" different multifocal IOLs in fellow eyes, results showed differences between the lenses in intermediate and near vision, and one-third of patients sought IOL exchange.

Various multifocal IOL technologies may afford better visual acuity results than implantation of a single multifocal IOL model bilaterally, but implanting an accommodating IOL (crystalens, eyeonics) and a multifocal implant in fellow eyes appears to have no advantage over bilateral implantation of the accommodating IOL, according to analyses presented by Guy M. Kezirian, MD.

Hyperopic LASIK ablation centration on the entrance pupil center versus on the corneal vertex was compared in a prospective randomized study. The results favored the corneal vertex centration technique because it induced a more prolate profile and was associated with less induction of coma-like aberrations.

No surgical procedures are without the risk of complications. The most frequently occurring complication after Descemet's stripping endothelial keratoplasty is detachment of the donor button. Attachment is easily achieved with rebubbling in a high percentage of cases. Optical coherence tomography is very useful to observe the interface and elucidate the cause of detachments.

When a prospective, randomized, observer- and subject-masked study compared an aspheric IOL and a spherical, single-piece IOL for functional performance after implantation in contralateral eyes, contrast sensitivity testing and night-driving performance results favored the aspheric IOL.

A series of prospective, randomized, masked studies was conducted to compare aqueous concentrations and prostaglandin E2 (PGE2) inhibition achieved in patients undergoing cataract surgery and treated preoperatively with different topical nonsteroidal anti-inflammatory drugs (NSAIDs). The results suggest the superiority of ketorolac 0.4% (Acular LS, Allergan) for preventing inflammation and cystoid macular edema after cataract surgery.