ADVANCEMENTS IN SURGICAL TECHNOLOGY AND EFFICIENCY
Innovative Approaches to Challenging Cases With Advanced Technology
BY STANISLAO RIZZO, MD
The CONSTELLATION® Vision System is a sophisticated machine that provides many helpful options for vitreoretinal surgeons. It gives us the versatility to perform surgery using 20, 23 or 25-gauge with ultra-high cutting rates and more control tools than we have ever had, such as flow control, vacuum control and IOP compensation. How can we manage all of these options? I will offer some advice on how to use these new features for your most challenging cases.
ULTRA HIGH-SPEED CUTTING
With the ACCURUS® Surgical System, using 20-gauge and 250 mmHg of vacuum at 2500 cuts per minute (cpm), the flow rate is 12 cc/min. When using the same gauge and vacuum at 5000 cpm with the CONSTELLATION® System, the flow rate is 10 cc/min, a difference of only 2 cc. So, to remove 4 cc of vitreous with a flow rate of 12 cc/min takes 20 seconds, whereas with a flow of 10 cc/min, it takes 24 seconds. The difference is only 4 seconds. Is it worthwhile to risk causing traction on the retina by using a lower cut rate to save only 4 seconds? In my opinion, absolutely not!
PROPORTIONAL VACUUM
The CONSTELLATION® Vision System has 3D and proportional vacuum control. I prefer the proportional vacuum control, which enables me to use the highest cut rate possible, 5000 cpm, and control flow via the foot pedal. For example, when using 25+, I can increase the vacuum from 0 to 650 mmHg by pressing the foot pedal, while the cut rate remains the same.
In a typical retinal detachment case, using proportional vacuum controlled by the foot pedal, I can remove the vitreous while working near the detached retina. This is a precise maneuver using the highest cut rate possible.
FLOW LIMITING
The CONSTELLATION® Vision System also has a flow limiting feature, which is useful, especially when operating on a large break in the peripheral retina. By limiting the flow, I can protect against unwanted surges into the vitrectomy probe port, and I can remove the vitreous and eventually the anterior flap of the retinal break safely.
INNOVATIVE APPROACHES
This new technology enables us to use new techniques. A year ago, I had a tractional retinal detachment case. A major complication in this type of case is the bleeding that occurs when removing the fibrovascular stalks. I performed an elegant bimanual surgical procedure using 23-gauge forceps and scissors because the membrane completely covered the posterior pole. With the CONSTELLATION® 25-gauge probe, however, I can employ a much more elegant and efficient technique. I can now remove all of the membranes and fibrovascular stalks from the retina using only the vitrectomy probe (Figure 1). This technique is not only as precise as the bimanual approach, but it is faster and, in my opinion, safer, because it reduces the need for instrument exchanges and, above all, it reduces intraoperative bleeding.
Figure 1. As shown in this case, I can now remove membranes and fibrovascular stalks from the retina using only the vitrectomy probe of the CONSTELLATION® Vision System.
Recently, I operated on a young patient with post-traumatic retinal detachment. I used all of my resources, including flow and vacuum control, but I felt that for this case, the surgical strategy was wrong. So, I removed the bubble of perfluorocarbon liquid I had previously injected to flatten the retina and injected triamcinolone over the retina. Surprisingly, I found the vitreous completely adherent on the posterior pole (Figure 2).
Figure 2. After finding the vitreous completely adherent to the posterior pole in this case, I was able to safely remove the vitreous near the detached retina using the vitrectomy probe of the CONSTELLATION® Vision System.
This case shows the advantage of having a probe with port optimization, meaning the opening is closer to the tip. With port optimization, I can safely remove the vitreous near the detached retina. Then, I can remove the vitreous from the posterior pole toward the periphery, and the surgery is done.
IMPROVED OUTCOMES
The new technology and features now available with the CONSTELLATION® Vision System give us many options to improve our surgical techniques. We can now perform safer and more efficient surgeries, thus reducing our efforts and resources, optimizing the use of the operating theater, and saving time and money. The main objective is better outcomes for our patients.
Stanislao Rizzo, MD, is chair of ophthalmic surgery at Azienda Ospedaliero-Universitaria Pisana in Pisa, Italy. He is a consultant for Alcon Laboratories, Inc.