A total of 91 eyes from 91 consecutive patients, each of whom underwent primary implantation of sulcus-fixated foldable acrylic IOLs, were assessed. AcrySof MA60BM and Sensar AR40e multi-piece IOLs, and AcrySof SA60AT and BioVue single-piece IOLs were implanted. The type of IOL and axial length (AL) were analysed to identify differences in the spherical equivalent between the predicted refraction values obtained using the SRK/T formula and the manifested refraction values.

Myopic shift of foldable acrylic intraocular lenses after sulcus 

AIMS:

The aim of this retrospective study was to identify factors affecting myopic shift from predicted values of refraction after sulcus fixation of foldable acrylic intraocular lenses (IOLs).

METHODS:

RESULTS:

The mean myopic shift from the predicted refraction calculated using the SRK/T formula was -1.04 dioptres (D) ±0.85 SD with sulcus fixation of the foldable acrylic IOLs. The type of IOL (multi-piece vs single-piece) did not affect the degree of myopic shift (p=0.100, independent t-test). However, as the AL increased, the myopic shift decreased (p=0.033, r=0.223, Pearson's correlation).

CONCLUSION:

The myopic shift from the predicted refraction differed following sulcus fixation of foldable acrylic IOLs based on the AL, and therefore surgeons should take the AL into account when they determine the IOL power for sulcus fixation procedures.

PMID:

 

22872670

 

[PubMed - in process]

LinkOut - more resources

New lens combining refractive and diffractive designs shows promise

osn supersite

Preliminary clinical outcomes indicate that the OptiVis multifocal IOL is a promising new concept, combining the benefits of both diffractive bifocal and progressive refractive designs, according to one surgeon."The center of the lens, within 1.5 mm of diameter, has a progressive refractive design for distance and intermediate vision. The intermediate ring, within 1.5 mm and 3.8 mm, has an apodized diffractive bifocal design for distance and near that reduces halos. The peripheral ring has a prolate, aspheric design to improve image contrast at distance," Matteo Piovella, MD, said at the winter meeting of the European Society of Cataract and Refractive Surgeons.The OptiVis IOL (Aaren Scientific) was implanted in 67 eyes of 39 patients through a 2.8- to 3-mm incision. Twenty-eight implants were bilateral
Through-focus response curves for OptiVis from optical bench testing showed broad distance focus and greater depth of focus in the intermediate range compared with other multifocal IOLs and sharp near focus, similar to simple diffractive bifocal IOLs.

Rituximab to Treat Thyroid-Associated Ophthalmopathy

January’s Ophthalmology

A retrospective, interventional case series by Chong et al. demonstrates a clinical benefit of anti-CD20 (rituximab) in the treatment of severe thyroid-associated ophthalmopathy that is refractory to corticosteroid therapy or orbital decompression.

Thyroid-associated ophthalmopathy affects 30 to 50 percent of patients with Graves’ disease. It is thought that B cells may produce autoantibodies against thyroid-stimulating hormone receptors and insulinlike growth factor-1 receptors. Rituximab depletes B cells by enhancing apoptosis and promoting antibody-dependent cellular toxicity and complement-dependent cellular toxicity. In the six patients studied, four developed dysthyroid optic neuropathy prior to the rituximab treatment. Orbital inflammation and dysthyroid optic neuropathy improved following rituximab treatment in all six patients. No one experienced disease relapse, and proptosis remained stable.

While the authors urge caution due to the uncontrolled nature of the study, they assert these data justify conducting prospective studies to determine whether rituximab is a viable alternative in patients with progressive, corticosteroid-resistant thyroid-associated ophthalmopathy.

Refractive surgical practices in persons with human immunodeficiency virus positivity or acquired immune deficiency syndrome

Eyeworld


Investigators here wanted to feel out what refractive practices were currently doing with regard to performing elective surgery on those who had either tested positive for HIV or, who had Acquired Immune Deficiency Syndrome (AIDS). Of the 285 practitioners who responded to an anonymous, web-based survey emailed to members of the International Society of Refractive Surgery, 50.2% said that they were willing to consider those with HIV positive status as candidates, while just 35% said that they would consider performing elective surgery on those with AIDS. Of those who would perform the surgery, 72.7% claimed that they take extra precautions in such cases, such as wearing double layers of gloves, and evacuating the laser plume immediately after surgery. They also said that they would limit any procedures to one eye and would make sure that the surgery was the last on the schedule for the day in such patients.

Femto face-off

Eyeworld

Experts argued the advantages of using competing femtosecond lasers in a face-off of the different technologies Monday. Explaining the basic differences between the currently available lasers, N. Timothy Peters, M.D., Portsmouth, N.H., said that the current IntraLase FS and Femtec systems (Technolas Perfect Vision, St. Louis) use higher-energy, lower-frequency pulses than the Femto LDV laser (Ziemer, Port, Switzerland) and the VisuMax (Carl Zeiss Meditec, Dublin, Calif.) falls somewhere in between.
Dominating market use at 91%, the newest generation of IntraLase is faster with lower energy and tighter spot separation, therefore producing better results than before, said. Daniel Durrie, M.D., Overland Park, Kan. With over 350,000 procedures having been performed using the IntraLase, there is substantial evidence for its safety and efficacy.
Arguing for the VisuMax, Dan Z. Reinstein, M.D., M.A., N.Y., said the technology provides very high flap thickness accuracy and reproducibility, fast treatment outcomes, excellent visual outcomes in combination with the MEL80 (Carl Zeiss Meditec, Dublin, Calif.), while extremely user-friendly for surgeons and affording the patient a more comfortable experience.
The formation of an opaque bubble layer (OBL) within the cornea during flap creation is a common issue with femtosecond laser technology, said Dr. Reinstein, as it can interfere with the ability of eye-tracking systems to function properly. The VisuMax, he said, produces a very thin layer of OBL, which he and colleagues have found dissipates in the time between flap-creation. There is no time wasted in the operating theatre and an average treatment time for bilateral LASIK is 12 minutes with the VisuMax and MEL80.
Speaking about the Ziemer LDV, Richard Foulkes, M.D., Chicago, said the lack of an epithelial edge gap is one advantage the technology has over the IntraLase FS. In addition, Dr. Foulkes said the technology produces no OBL or transient light sensitivity (TLS).

Glaucoma update

Eyeworld

A new refillable and programmable drug delivery system for glaucoma that could also change treatment approaches to many ocular diseases in the future was described. Designed to solve glaucoma patient compliance issues, the device (REPLENISH, Pasadena Calif.), is implanted in the patient’s eye through minimally invasive surgery, and supplies the appropriate amount of drug needed at determined intervals into the anterior chamber, said Mark S Humayun M.D., Ph.D., Los Angeles. The intraocular drug pump, which is made of biocompatible material, can last between five to 10 years and can be refilled while implanted. Pre-clinical trials showed successful transconjunctival refilling every four to six weeks for a period of four to six months. In addition, Dr. Humayun said, switching medications in between refills is possible as the device is able to flush out its reservoir. In the future, the system may also be designed to include two chambers for delivery of two drugs. Concerns with the device include endothelial damage, infection, tube clogging and the amount of drug that remains in the reservoir.
Looking further into the future, Stuart J McKinnon, M.D., Ph.D., Durham, N.C., presented hope for glaucoma specialists trying to reduce intraocular pressure in their patients. Dr. McKinnon described the possibility of neuroprotective treatment for glaucoma. He explored three strategies including blocking the formation or aggregation of amyloid-β, complement activation, and tumor necrosis factor-α signalling, and said they represented considerable promise.

Annual ISRS/AAO survey reflects 15% drop in refractive procedures

Eyeworld

In its ninth year, and its first year completed online, the ISRS/AAO annual survey provided insights into national trends in refractive surgery. Among the findings Richard J. Duffey, M.D., Mobile, Ala., presented included ISRS/AAO members endured about a 15% dip in refractive procedures last year. Most of the losses were seen in LASIK volume, but the drop was not “across the board” for all refractive procedures. In fact, Dr. Duffey said refractive lens exchange procedures and phakic intraocular (IOL) implantations both went up last year, to 8% and 16% of refractive procedures, respectively. The VISX laser system (Abbott Medical Optics, AMO, Santa Ana, Calif.) continues to be the most popular system, but the WaveLight system (Alcon, Fort Worth, Texas) is also gaining in popularity and last year was no different. VISX’s popularity has dropped to 2:1 ratio to WaveLight, Dr. Duffey said. In refractive multifocal IOLs, Crystalens (Bausch & Lomb, Rochester, N.Y.) remains the most popular with ReStor (Alcon) not far behind. In a distant third is the Tecnis Multifocal (AMO), which has essentially replaced the ReZoom among those surveyed, Dr. Duffey said.