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.
A new microincision IOL (MI60 Micro Incision IOL, Bausch & Lomb) can be implanted easily through a 2-mm incision. Clinical results of one study indicate that the IOL has good stability and efficacy and seems to reproduce the results obtained with hydrophilic acrylic IOLs designed for implantation through a 3-mm incision.
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.
Pseudoexfoliation (PXF) is a common disorder that mandates special attention when cataract surgery is indicated.
Ophthalmologists who use botulinum toxin type A to help patients improve their appearance should add the use of hyaluronic acid (HA) fillers to their procedures because they have many ideal characteristics, recommends one oculoplastics specialist. HA fillers are made of natural substances; no toxic effects are known. They can be used alone or in combination with permanent procedures such as fat transplantation; they have a combined effect with botulinum toxin; and they can be eliminated, if needed, through the use of hyaluronidase. HA fillers also have a low incidence of side effects, are easily stored, do not need to be refrigerated, and come in preloaded syringes with small needles.
Ketorolac tromethamine 0.4% (Acular LS, Allergan) plus steroid improves the visual outcome following uncomplicated cataract surgery by reducing the incidence of retinal thickening, according to a recent multicenter study. This combination therapy also reduces the incidence of cystoid macular edema. These findings suggest that this therapy would be beneficial in all cataract surgery cases.
In a randomized comparison study of two antibiotic/steroid combinations, tobramycin 0.3%/dexamethasone 0.1% controlled the clinical signs of inflammation more quickly than tobramycin 0.3%/loteprednol 0.5% in patients with moderate blepharokeratoconjunctivitis.
An investigational formulation of bromfenac ophthalmic solution has been developed for once-daily administration. Preliminary analyses of data from two phase III clinical trials indicate it is safe and effective for treating ocular pain and inflammation after cataract surgery.
Administration of nepafenac, a topical nonsteroidal anti-inflammatory drug, and prednisolone resulted in a significantly lower rate of pseudophakic macular edema following cataract surgery compared with the rate in patients who received only prednisolone.
Topical cyclosporine ophthalmic emulsion 0.05% may be a new treatment option for patients with inflamed pterygia that are refractory to conventional therapy of topical steroids and emollients. The modulating effect of the drug also may reduce or delay the need for excision of pterygia.
The fixed combination of loteprednol etabonate 0.5%/tobramycin 0.3% provides a safe and potent corticosteroid with an anti-infective agent that has broad-spectrum activity against important gram-negative and gram-positive organisms.
