NOV 2013

EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.

Issue link: https://digital.eyeworld.org/i/220233

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Page 16 of 122

November 2013 Shpilkes continued from page 13 IMPORTANT SAFETY INFORMATION FOR THE VERION™ REFERENCE UNIT AND VERION™ DIGITAL MARKER CAUTION: Federal (USA) law restricts this device to sale by, or on the order of, a physician. INTENDED USES: The VERION™ Reference Unit is a preoperative measurement device that captures and utilizes a high-resolution reference image of a patient's eye in order to determine the radii and corneal curvature of steep and flat axes, limbal position and diameter, pupil position and diameter, and corneal reflex position. In addition, the VERION™ Reference Unit provides preoperative surgical planning functions that utilize the reference image and preoperative measurements to assist with planning cataract surgical procedures, including the number and location of incisions and the appropriate intraocular lens using existing formulas. The VERION™ Reference Unit also supports the export of the high-resolution reference image, preoperative measurement data, and surgical plans for use with the VERION™ Digital Marker and other compatible devices through the use of a USB memory stick. The VERION™ Digital Marker links to compatible surgical microscopes to display concurrently the reference and microscope images, allowing the surgeon to account for lateral and rotational eye movements. In addition, the planned capsulorhexis position and radius, IOL positioning, and implantation axis from the VERION™ Reference Unit surgical plan can be overlaid on a computer screen or the physician's microscope view. CONTRAINDICATIONS: The following conditions may affect the accuracy of surgical plans prepared with the VERION™ Reference Unit: a pseudophakic eye, eye fixation problems, a non-intact cornea, or an irregular cornea. In addition, patients should refrain from wearing contact lenses during the reference measurement as this may interfere with the accuracy of the measurements. Only trained personnel familiar with the process of IOL power calculation and astigmatism correction planning should use the VERION™ Reference Unit. Poor quality or inadequate biometer measurements will affect the accuracy of surgical plans prepared with the VERION™ Reference Unit. The following contraindications may affect the proper functioning of the VERION™ Digital Marker: changes in a patient's eye between preoperative measurement and surgery, an irregular elliptic limbus (e.g., due to eye fixation during surgery, and bleeding or bloated conjunctiva due to anesthesia). In addition, the use of eye drops that constrict sclera vessels before or during surgery should be avoided. WARNINGS: Only properly trained personnel should operate the VERION™ Reference Unit and VERION™ Digital Marker. Only use the provided medical power supplies and data communication cable. The power supplies for the VERION™ Reference Unit and the VERION™ Digital Marker must be uninterruptible. Do not use these devices in combination with an extension cord. Do not cover any of the component devices while turned on. Only use a VERION™ USB stick to transfer data. The VERION™ USB stick should only be connected to the VERION™ Reference Unit, the VERION™ Digital Marker, and other compatible devices. Do not disconnect the VERION™ USB stick from the VERION™ Reference Unit during shutdown of the system. The VERION™ Reference Unit uses infrared light. Unless necessary, medical personnel and patients should avoid direct eye exposure to the emitted or reflected beam. PRECAUTIONS: To ensure the accuracy of VERION™ Reference Unit measurements, device calibration and the reference measurement should be conducted in dimmed ambient light conditions. Only use the VERION™ Digital Marker in conjunction with compatible surgical microscopes. ATTENTION: Refer to the user manuals for the VERION™ Reference Unit and the VERION™ Digital Marker for a complete description of proper use and maintenance of these devices, as well as a complete list of contraindications, warnings and precautions. © 2013 Novartis 9/13 VRN13015JAD-PI cated? In fact this IOL is probably not dislocated at all, i.e., it didn't fall below where it was supposed to rest. The myopic eye typically (but not always) has a large sulcus, and the IOL was made for in-the-bag fixation, so the IOL was correctly in the sulcus and too small to center properly. This calls into play something I have taught for the last two decades: If you must put an IOL in the sulcus, you must fixate it with a suture or by optic capture. In the early days of IOLs the haptic/haptic diameter was as much as 2 mm larger than the IOLs of today, because sulcus placement was a frequent practice, given the relative instability of the 'can opener' capsulotomy to centrifugal vector forces from the placement of an in-the-bag IOL. "In the case presented, the IOL is not fused on the posterior capsule, which is likely to be stable. Although reformation of the capsular bag with repositioning of the IOL within the bag is often a good option, I would not try to reopen this particular bag, since the leaflets are fused and the presence of PXS suggests the possibility of zonular instability. Another option would be to perform a posterior CCC and capture the optic behind it. However, the IOL currently in place would produce a marked hyperopic shift if placed behind the capsule (since the calculation shows that even in-thebag placement would render the patient hyperopic). Thus, if optic capture were used, I would first exchange the IOL, implanting one of higher dioptric power. "The least invasive approaches can be performed utilizing the currently implanted IOL. I would favor those in this case because the IOL is of correct power for sulcus/retroiridal fixation. I have recently found that using the so-called 'glued IOL technique' popularized by Amar Agarwal, MD, and coworkers, is a very satisfactory fix for these eyes. "Of course, the simplest fixation method is to capture the optic through the undilated pupil, and suture it to the peripheral iris using a modified McCannel technique with 9-0 polypropylene suture. "One final caveat: Don't forget to perform a small peripheral iridectomy." Dr. Raviv added his thoughts to this case: "Looks like the small pupil and likely an intraoperative bag dehiscence (PXS exacerbated) created this complication of a dislocating sulcus PCIOL. While the sulcus is generally a safe place for a three- piece IOL with a localized posterior capsule (or even anterior capsular) complication, it can cause trouble in the case of zonular loss. A sulcus IOL, after all, rests on the peripheral anterior capsule and its zonular attachments to the ciliary body. In this case, a portion of the inferior zonules is likely completely missing creating a potential space for the IOL to fall. "I would approach this surgical IOL repositioning with two pathways in mind—either using the existing capsule for fixation or IOL suture fixation to the iris. After placing OVD and iris hooks, I would test the stability of the bag complex. If stable, I would use a 23-gauge vitrector (either anteriorly or pars plana if needed) to create a small 4.5 mm central PC opening behind the IOL, and I would push the optic posteriorly in a posterior optic capture configuration. Another option I like is performing a YAG capsulotomy through the PC (in the photo, the fused anterior capsule appears well centered to the pupil), and then surgically capture the optic through the fused AC/PC capsular ring. "Alternatively, if surgically the capsule is overly compromised, the IOL can be sutured to the iris and the floppy capsule excised with 23gauge vitrectomy." What was done When I first saw this case I was going to exchange the lens for a STAAR Surgical (Monrovia, Calif.) three-piece silicone lens and suture one haptic to sclera to prevent it from shifting position. I like the STAAR lens in the sulcus in these big eyes because of its 13.5 mm length (14 mm in under 4 diopter power) and larger optic (6.3 mm). I also considered using a "glued in lens technique," but that is a technique that makes the presence of the capsular bag all but redundant, and I thought it would be a good idea to utilize the capsule that was present here. I also felt that the inevitable subsequent YAG capsulotomy that would be necessary could create problems in this high myope that I'd like to avoid, namely vitreous prolapse (given the fact that there would be no tamponade of the vitreous face by the IOL over the area to be YAG lasered). I was also concerned about possible pitting of a silicone IOL given the fused anterior and posterior capsule behind the lens optic and the energy that would be require to YAG this. Also without enough tension on the capsule it can be even more difficult to laser. I wanted a solution that would simplify the surgery, address the refractive error, minimize risk to the retina and avoid possible problems related to the YAG. I decided to remove this lens and then dissect the anterior capsule off of the posterior capsule. Although the posterior capsule did not remain intact the anterior capsule rim did, and I was able to push the anterior hyaloid face back with viscoelastic so that optic capture was possible through both the anterior and posterior capsule opening into Berger's space. There was no vitreous presentation as the anterior hyaloid remained intact throughout the case. I was able to put in an 11 diopter Tecnis three-piece (Abbott Medical Optics, Santa Ana, Calif.), which as my calculations predicted ended up with a plano refractive outcome. The surgery was quite simple and took very little time to do. The patient will never require a capsulotomy because there is no capsule behind the lens. My approach did entail a slight risk of requiring a vitrectomy during surgery, but I felt the risk was relatively low and in fact a vitrectomy was not required. This case was similar to doing a posterior capsulorhexis where it is possible to preserve the anterior hyaloid face by using viscoelastic to gently push it away and thus define Berger's space. When I first started this case I thought I might be able to open the capsular bag without breaking the posterior capsule, but the adhesions were too strong between the anterior capsule and posterior capsule to allow this. EW Editors' note: Dr. Condon has financial interests with Alcon (Fort Worth, Texas), Allergan (Irvine, Calif.), and MST (Redmond, Wash.). Dr. Raviv has financial interests with Alcon, Abbott Medical Optics (Santa Ana, Calif.), and Bausch + Lomb. Dr. Rosenthal has financial interests with Bausch + Lomb, Alcon, Abbott Medical Optics, and Rayner (East Sussex, U.K.). Dr. Safran has financial interests with Bausch + Lomb. Contact information Condon: garrycondon@gmail.com Raviv: tal.raviv@gmail.com Rosenthal: kr@eyesurgery.org Safran: safran12@comcast.net

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