I have had the opportunity to evaluate a number of machines designed to facilitate both anterior and posterior segment surgery, and this has allowed me to develop criteria for judging their effectiveness. It is important for phaco-vitrectomy machines to exhibit the following characteristics:
- Efficiency of the vitrectomy probe at every cutting rate;
- Reliable control of infusion pressure to the eye;
- Flexibility to address both anterior and posterior segments;
- Reliable injection and extraction of fluid.
After recently using the Stellaris PC in a range of challenging and complex cases, I can confirm that this phaco-vitrectomy surgical platform demonstrates efficiency in all of these areas. I especially appreciate its flexibility to select anterior or posterior segment functionality, as I find myself performing combined surgery with increasing frequency.
The dual linear footpedal of the Stellaris PC is extremely helpful in vitreoretinal surgery. It allows the surgeon to control all the parameters of the machine, for example simultaneously regulating cutting and aspiration levels independently. This allows the surgeon to use the probe as forceps and scissors simultaneously, grasping membranes and cutting them without losing the grip on the tissue. The pedal's wireless operation helps to prevent clutter in the operating room. Also advantageous on the Stellaris PC is its dual xenon and mercury-xenon light source and filters.
This article describes some of the capabilities I have found helpful when using the Stellaris PC in a number of challenging surgical cases.
Peripheral vitrectomy with scleral indentation in phakic eyes is feasible with either 25- or 23-gauge instrumentation. Peripheral shaving of vitreous can be performed without bending the probe or losing cutting efficiency, while looking with direct view through the operating microscope (Figure 1) or through the binocular indirect ophthalmomicroscope (BIOM; Figure 2).
Even in extremely anterior maneuvers, such as removing a capsular bag (Figure 3), the 25-gauge vitrectomy probe does not bend or lose efficiency.
During exchange of fluids, for instance heavy perfluorocarbon liquid (PFCL) with silicone oil, the probe can be used to aspirate subretinal PFCL bubbles without aspirating the edge of an adjacent retinotomy. Indentation can be performed while at the same time maintaining good control of intraocular pressure (IOP) in what can be an extremely stressful, complicationthreatening situation.
In an eye with total retinal detachment and total attachment of the vitreous to the retina, I was able to use the vitreous cutter alone to separate the vitreous, and to aspirate PFCL bubbles (Figure 4), without damaging the retina. These delicate maneuvers were possible both at the posterior pole and in the periphery. To dissect the vitreous cortex from the detached retina, I stabilized the posterior retina with PFCL. By balancing the cutting rate and aspiration, it was then possible to dissect the vitreous cortex just using the vitrectomy probe.
During combined phaco-vitrectomy, an unwanted luxation of the crystalline lens may occur. When this takes place, the lens can be removed fairly quickly with only the 25-gauge vitrectomy probe, without the need for a fragmatome (Figure 5).
I have also had the opportunity to evaluate a number of illumination options on the Stellaris PC. Several types of light fibers can be connected directly to the light source of the Stellaris PC, including chandelier lights.
The chandelier, which allows the use of bimanual techniques, provides more than enough light to perform peripheral vitrectomy (Figure 6), as well as maneuvers at the posterior pole. The green filter on the xenon light source of the Stellaris PC can be used to enhance contrast for posterior pole maneuvers (Figure 7).
My experience in these cases and others demonstrates that any challenging surgical maneuver can potentially be performed with the Stellaris PC due to its versatility.
Barbara Parolini, MD, is Director of the Vitreoretinal Service at the Istituto Clinico S. Anna in Brescia, Italy. Dr. Parolini is a consultant for Bausch + Lomb. She may be reached at email@example.com.