The Constellation is the culmination of over three decades of evolutionary development of vitreous cutters and fluidics, new and improved tools, illumination sources, phaco technology, systems integration, efficiency systems, and advanced user interface design. The principal author is the architect of the Alcon Constellation Vision System.

The vitreous infusion suction cutter (VISC) and RotoExtractor were single-port, large-incision, so-called full function, slow-speed, rotary, electric cutters with aspiration provided by a syringe operated by the assistant. The Berkley Bioengineering Ocutome 800, developed by Conor O’Malley and Ralph Heinz, was the first three-port, 20-gauge (0.89 mm) system and had the first lightweight, pneumatic probe and surgeon foot pedal–controlled, on-off aspiration, a major advance. Berkley Bioengineering subsequently was acquired by Coopervision, and Coopervision was later acquired by Alcon. The Coopervision Ocutome 8000, developed by Carl Wang, his engineering team, and the author, had the first linear suction (now used on all vitrectomy and phaco machines), an integrated light source, and a connected fragmenter. The MidLabs MVS system, developed by Carl Wang and the author, had the first disposable pneumatic cutter, a crucial improvement over reusable cutters with low-performance cutting. After the original MidLabs system was acquired by Alcon Laboratories, the author started InnoVision and began the development of the Ocular Connection Machine (OCM). The OCM had a dual actuation InnoVit cutter with limited angle rotary cutting at 1,500 cuts per minute, linear diathermy, tool ID, an articulated arm with integrated tubing management, servo-controlled intraocular pressure (IOP), a graphical user interface with soft keys, integrated xenon illuminator, integrated fragmenter, auto–gas mixing, auto fluid-air exchange valving, and power scissors. The InnoVision OCM technology was never commercialized and was later acquired by Alcon Laboratories, and I became a consultant for Alcon. Many of the OCM concepts were improved upon and incorporated into the highly successful Accurus system, which included an advanced graphical user interface with soft keys and global functions, VGFI (vented gas-forced infusion), integrated fragmenter, silicone injector (VFC), and a halogen light source. 25-gauge and later 23-gauge tools were developed for the Accurus platform and are now in their third generation. A nonintegrated EyeLite 532-nm diode-pumped laser and later a nonintegrated xenon source were developed to use with the Accurus system.

The Constellation incorporates new, improved implementations of all the concepts incorporated in the OCM as well as the Accurus and adds many new capabilities. The vitreous cutter is the pivotal component of any vitreoretinal surgery system; the Constellation UltraVit cutter utilizes dual pneumatic actuation (no spring return axial cutter) such as the InnoVit and currently operates at 5,000 cuts per minute (Fig. 3.1). Because it is diaphragm driven, it eliminates the friction of the InnoVit piston, provides the familiar axial cutter format, and scales better to 23-, 25-, and even 27-gauge form factors. The cutter is driven using a proprietary variable duty cycle technology dependent on the dual actuation system. Variable duty cycle control enables the use of a biased closed approach to produce increased port-based flow limiting when working in close proximity to the retina, so-called vitreous shaving. Alternatively, port-based flow limiting can be decreased by using a biased open approach enabling greater flow rates when doing core vitrectomy. The aspiration system has an extremely low latency response time to a foot pedal command for vacuum decrease or increase because of a new, triple proportional valve aspiration system and cassette design. Sensor-based, fast-response, digital flow control and flow limiting facilitate working safely near the retinal surface. The aspiration system provides continuous linear (proportional) reflux as well as microreflux for all aspiration tools.

Figure 3.1 Cutaway view of UltraVit 5,000 cpm vitreous cutter showing dual diaphragm actuation.

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