AutoSert® IOL Injector 1) Were the Benefits for the Patients and Surgeons Worth it? (R. Mencucci, Florence, Italy)
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r. Mencucci started her talk by stating that the success of cataract surgery is based on a perfect surgical technique and standardization of every step of the procedure, i.e. the incisions, the rhexis and IOL implantation. The challenges for the surgeon are that the current cartridges don’t fit an incision <2.4 mm, and the leading edge of the cartridge tip must be kept in constant close contact with the incision. In addition, the surgeon has to hold the injector with one hand and rotate the screw thread as quickly as possible, keeping the injector aligned with the incision axis. A few years ago Alcon launched an automated delivery device (AutoSert® IOL Injector handpiece [AutoSert® HP]). One question that may come to mind is whether this is a “gadget” for the smartest and most up-to-date surgeons. Perhaps more serious concerns may arise, notably: • Higher costs are associated with the use of AutoSert® HP as compared with currently available injectors. • The surgical staff needs just a little more time for setting up the hand piece, as compared with manual injectors. Loading the IOL in the cartridge and pushing it safely into the eye took approximately only 12-13 more seconds with AutoSert® HP than with currently available injectors. • The availability of easy to use injectors on the market, for instance Monarch® III. Dr. Mencucci said, “Monarch® III is one of my favourites”. Monarch® III provides a very good control of the insertion procedure, but both hands are needed and thus a “blind” moment may occur during the insertion (i.e. a lapse of time in which the surgeon cannot see very well what he/she is doing). The syringe (pre-loaded delivery system) with a “one-hand” procedure, requires significant force to compress the IOL and move it into the cartridge. Then the force needed to make the IOL exit the cartridge rapidly drops and thus overshooting may occur. With time, the plunger does not always ensure smooth movements.9 • Low acceptance of AutoSert® HP by surgeons, because they consider they don’t need it. Dr. Mencucci showed some videos highlighting examples of issues with IOL injection, even with Monarch® and Acrysof: the stress on the incision, the corneal folds and sometimes the “blind” moment. So why use AutoSert® IOL Injector HP? 1) It helps the surgeon manage forces involved in IOL delivery. 2) It is a motorised system that allows continuous movement (injection) without disruption, contrary to twist-style injectors. 3) There is a lower risk of uncontrolled overshoot, as can happen with plunger-style inserters (pre-loaded systems). 4) Both hands are available to stabilize the eye. 5) There is the possibility to standardize IOL injection velocity (4.4 mm/ sec is the maximal speed). Indeed, with AutoSert® HP, the speed of IOL injection can be modulated, with the possibility to pause for less than a second to verify if everything is under control, before successfully completing the insertion. Incision enlargement is an issue with the current cartridge as the trend is to reduce the incision size. A study by Allen et al.10 showed significantly less incision enlargement with AutoSert® used at a fast injection speed (4.4 mm/sec) than with either Monarch® III or AutoSert® HP at 1.5 mm/sec. It is also known that a more regular incision is of particular importance to reduce the possibility of post-op wound leak and less ingress of fluid and bacteria from the conjunctival sac. Dr. Mencucci showed some OCT pictures comparing injections with Monarch® III and AutoSert® HP. The overall wound architecture was perfectly maintained with AutoSert® HP while a less regular appearance of wound architecture due to less accurate insertion is observed with Monarch® III. Apart from these anterior segment OCT images, what’s happening on the endothelial side, the speaker asked. To answer this question, the presenter recently conducted some research on 40 porcine eyes. Twenty of them received an IOL by manual injection with Monarch® III through an incision of 2.2 mm and 20 with received the IOL by
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ALCON CENTURION® VISION SYSTEM COUNCIL MEETING 2014
Figure 6. Wound appearance following the use of AutoSert® HP (left) and Monarch® III (right) as seen on OCT
Figure 7. Incision as they look like following injection with AutoSert® HP
AutoSert® HP. She showed the appearance of the endothelial side of a 2.2-mm incision on electron microscope scans. In this particular case the injection was performed with AutoSert® HP through this incision. We can note how smooth and regular, uniform, and consistent the margins are. It is also important to observe the details of the lateral margins and notice the minimal impact of AutoSert® HP on the surrounding tissue. With Monarch® III, the appearance, even though well-defined is less smooth and regular in most cases, with a more extended involvement of surrounding tissue. The lateral margins are regular and appear similar to those with AutoSert® HP only in some cases. According to Dr. Mencucci this may not have any clinical importance, but the difference is impressive. Nowadays, there is striking, remarkable evidence supporting the idea that a perfect wound architecture is of paramount importance in preventing endophthalmitis. According to Dr. Allen’s paper as well as in Dr. Mencucci’s experiments, the size of the inner side of the incision was smaller in AutoSert® HP specimens as compared with manual ones (Monarch® III). In summary, AutoSert® HP is simple to set up and use, with little-tono learning curve. It alleviates a potentially significant challenge for the surgeons when it comes to controlling the injection process. The IOL implantation can be carried out smoothly, and the incision is less
Figure 8. Appearance of incision following injection with Monarch® III
Figure 9. Incisions in specimens injected with AutoSert® HP (left) and Monarch® III (right)