EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/78721
16 EW NEWS & OPINION Pars continued from page 15 traction damage results. Unless FP 3 is engaged, cutting occurs without vitreous removal. Vitrectomy settings should limit port-based flow, and therefore vitre- ous traction, by setting the highest cut rate available. This ranges from 400 on older machines to 2,500 cuts/min on newer models. Take your time with a low aspiration flow rate—usually 20 is panel set for 20- gauge vitrectomy and 15 for 23- gauge. Vacuum must be at the low- est setting that results in removal of vitreous; generally 200-250 for 20- gauge and 350-500 for 23-gauge. This varies depending on how much dispersive OVD is present and will usually need to be higher than the default setting, which is best for our retina-vitreous colleagues who do not have OVD present at all during the pars plana approach. Many ma- chines default to linear for vacuum Femtosecond INSTRUMENTS Thorlakson Eye Speculum Adjustable mechanism 10mm rounded wire blades designed to accommodate the suction ring of the FEMTO LVDTM laser. in vitrectomy mode, but I prefer that the scrub assistant adjust the vac- uum up until effective on panel set- ting. This strategy allows the surgeon to be anywhere in FP 3 without regard to excursion. Many surgeons are tentative during a com- plication. Pedal to the metal is less challenging, more efficient, and in the long run safer. The irrigation bottle height seeks a normotensive eye, around 80 cm, while the vac- uum is active. This can be similarly adjusted by the scrub at the sur- geon's direction. These parameters are not absolute; however, the goal is cutting the vitreous matrix as fre- quently as possible with low flow limiting traction, while balancing vacuum and irrigation, keeping a formed chamber and a normoten- sive eye. The activated vitrectomy port should always be visible through the pupil and should never be moved through vitreous with FP 3 (vacuum) activated. On completion of the vit- rectomy, FP 2 is maintained while moving the vitrector until the port is no longer visible. FP 1 is maintained until just before the vitrector leaves the eye in FP 0. Ultrasound cannot cut vitreous. It cannot be refluxed from an irriga- tion and aspiration port once incarcerated. At the endpoint of prolapsed vitreous removal, all sub- sequent maneuvers to remove lens material and place a stable IOL should only take place when the posterior segment and vitreous is compartmentalized by OVD parti- tioning or a captured optic se- questers it from the anterior structures. Finally, the risk of endoph- Thorlakson Z-LASIKTM Flap Lifter Combines a 1mm long, extra fine modified Sinskey Hook and a 12mm long bi-convex spatula with beveled notches. To lift LASIK flaps created with a femtosecond laser. thalmitis is higher with a broken hyaloid. Surgeons should consider systemic prophylaxis and treat pres- sure spikes prophylactically. Moni- toring and controlling inflammation to avoid CME is also important. Early post-op referral for retained lens fragments and peripheral retina indented exam is mandatory. Sur- geons should disclose complications to patients despite what may be an optimal post-op result. EW Editors' note: Dr. Arbisser has financial interests with Abbott Medical Optics (Santa Ana, Calif.) and Alcon. Contact information Arbisser: 563-323-2020, drlisa@arbisser.com EyeWorld factoid IntraLase® Flap Lifter Combines a 1mm long Sinskey Hook for finding the flap edge and a long, blunt, 11mm long hook to undermine the flap perpendicular to the hinge. According to the latest studies, age-related cataract is responsible for 48% of world blindness Source: World Health Organization 973-989-1600 r 800-225-1195 r www.katena.com ™ January 2012