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A comparison of dynamic IOP values during cataract extraction by phacoemulsification using high and low flow found that lower bottle heights result in lower fluctuations of IOP. An enhanced fluidics management system allows the use of a lower bottle height with concomitant use of high vacuum and aspiration flow rate, without compromising the stability of the anterior chamber.

A new phacoemulsification system (WhiteStar Signature with Fusion Fluidics, Advanced Medical Optics) combines existing phaco technology with a dual-pump fluidics system designed to enhance chamber stability. In addition, the technology offers a streamlined user interface and accessories that aim to enhance the efficiency of the operating room.

Cataract surgeons can reduce the rate of complication from intraoperative floppy iris syndrome (IFIS) by using certain techniques before and during surgery.

Results of a retrospective study show good visual acuity outcomes at near, intermediate, and distance, and high rates of satisfaction can be achieved using a strategy combining an accommodating IOL (crystalens, eyeonics) in one eye with the apodized diffractive multifocal IOL (AcrySof ReSTOR, Alcon Laboratories) in the other eye in patients undergoing cataract surgery or a clear lens exchange procedure.

Bimanual phacoemulsification wounds allow significantly greater ingress of fluid from the ocular surface compared with a microcoaxial incision. Even with the smallest of clear corneal incisions, wound integrity is critical. Surgeons should always look for incision distortion at the end of the case and should not hesitate to suture if necessary.

Robert H. Osher, MD, has designed a new phacoemulsification tip with a less angled tip configuration for use during microcoaxial techniques. It offers surgeons who prefer using a straight tip during phacoemulsification procedures the advantages of torsional ultrasound.

Bilateral implantation of the aberration-free aspheric IOL (SofPort AO, Bausch & Lomb) in a monovision approach can provides cataract surgery patients excellent binocular distance and near uncorrected visual acuity (UCVA) with high rates of spectacle independence and low rates of night-time vision complaints.

A refractive multifocal IOL (ReZoom, Advanced Medical Optics) is an effective method for diminishing dependence on glasses for refractive cataract surgery patients.

Use of an apodized diffractive IOL in patients needing cataract surgery after prior refractive surgery is considered to be contraindicated, but excellent outcomes can be achieved if optical results are near emmetropia. Success depends on control of surgically induced astigmatism, use of accurate formulae, careful patient selection, and enhancement as necessary.

Clear corneal wounds-with square or nearly square surface architecture-that are meticulously checked for incisional sealing are stable postoperatively, as demonstrated by the absence of hypotony and wound leakage. In a sealed clear corneal wound, IOP remains reasonably stable relative to the level set at the conclusion of the procedure.

New technology is enabling clinicians to perform quantitative as well as qualitative assessments of glaucoma patients. As this technology becomes more widely available, it will be important to match the output from the new imaging devices to clinical needs as well as to deal with practical issues such as the cost of buying and updating new devices.

Dislocation/decentration continues to be one of the most common concerns associated with foldable IOLs requiring explantation, followed by glare/optical aberrations and incorrect lens power, according the results of the ninth annual ASCRS/ESCRS foldable IOL survey.

Increasing use of erectile dysfunction (ED) drugs has added a new topic to the ophthalmologist-patient conversation: possible risks to the optic nerve in certain patients with glaucoma who are taking ED medications.

The routine use of topical anesthesia for cataract surgery appears to be safe, inducing yearly endothelial cell count reductions comparable with those seen in healthy eyes not undergoing the operation.

Presbyopia-correcting IOLs provide an extended range of good vision. Not all cataract surgery patients, however, are appropriate candidates for that technology, and there are other alternatives for gaining near vision. Time must be spent in precataract surgery counseling to assess the patient's desire for spectacle independence, suitability for a presbyopia-correcting IOL, and the benefits and trade-offs of all available alternatives.

A newly designed glaucoma shunt made of poly(styrene-b-isobutylene-b-styrene) (SIBS) is clinically biocompatible in the rabbit model and maintained 100% patency at 6 months after insertion. Histologically, minimal capsule fibrosis and minimal collagen deposits were observed around the implant. The most remarkable difference was the absence of myofibroblasts in the surrounding tissue in the SIBS group when compared with tubes made of silicone.

Safety studies using optical coherence tomography (OCT) to image eyes with a miniature telescope implanted showed that adequate central and peripheral corneal clearance were achieved in these eyes, supporting earlier evidence that the telescope is safe for long-term use. Further studies suggest that OCT also can be used in these patients to detect recurrence of choroidal neovascularization.

Preferential hyperacuity perimetry ([PHP] Foresee PHP, Notal Vision/ MSS) is an invaluable tool for the management of patients with age-related macular degeneration (AMD), according to ophthalmologists who have incorporated this diagnostic test into their practices.

Keisuke Kawana, MD, PhD, describes a prototype high-speed, swept-source, three-dimensional cornea and anterior segment OCT device (3D CAS-OCT) that was built by the Computational Optics Group at the University of Tsukuba. Dr. Kawana and colleagues used this OCT device to analyze anterior eye segments after glaucoma surgery and obtained clear images following procedures such as trabeculectomy, trabeculotomy, and laser iridotomy.

Several studies have suggested that new imaging instruments are as accurate as stereophotography in diagnosing glaucoma. The patient population used in a study, however, is likely to be significantly different from that found in a clinical practice, and factors such as disease severity and the size of the optic nerve also will influence the diagnostic accuracy of these instruments outside of the clinical trial setting.

Two baseline characteristics-drusen area and pigment abnormalities-are associated with the development of advanced age-related macular degeneration.

Proprietary instrumentation (Ocular Response Analyzer, Reichert Inc.) may provide clinical measures of corneal viscoelasticity (corneal hysteresis) and rigidity (corneal resistance factor). The device provides clinical information on the dynamic biomechanical properties of the cornea and may be able to identify eyes at risk of developing ectasia before LASIK.

Slit-scanning videokeratography is a useful tool for determining corneal power for IOL power calculation in post-hyperopic LASIK eyes, especially when preoperative refractive information is not available.

Dynamic stimulation aberrometry enables objective measurement of the range of accommodation after the implantation of accommodating IOL such as an accommodating lens, allowing physicians to determine optimal wavefront correction and individualize treatment.

Efekan Coskunseven, MD, and colleagues evaluated the predictability and reproducibility of flap thickness using the femtosecond laser and optical coherence tomography (OCT).

A new tool for pseudophakic IOL power calculation in post-laser refractive surgery eyes will help cataract surgeons provide more accurate refractive outcomes.

Refractive surgeons can easily obtain accurate IOP measurements following keratorefractive surgery with a non-contact, dynamic bi-directional applanation system (Ocular Response Analyzer [ORA], Reichert Inc.). The device also has been used to measure corneal biomechanical properties in potential refractive surgery candidates as well as after refractive surgery.

Some surprising findings surround phakic IOL implantation. At least in one large Midwest refractive practice, implantation of phakic IOLs is accounting for less than 1% of all refractive procedures. The incidence of enhancement procedures using LASIK or PRK is also very low-only 3%. Outcomes after additional excimer laser correction in patients with extreme myopia receiving one phakic IOL (Verisyse, Advanced Medical Optics) have been excellent.