Micro-coaxial technology allows for less invasive cataract procedures

Key Points

The micro-coaxial technology of the tri-modal cataract removal surgical system (Infiniti Vision System, Alcon Laboratories) permits surgeons to perform less invasive cataract procedures without having to change their surgical technique. Surgeons can remove a cataract with great efficiency through a 2.1- to 2.4-mm incision, using the same techniques and instruments that they use when operating through larger phaco incisions, so there is no significant learning curve with the micro-coaxial technique.

Because the system's fluidics are so exceptional, standard fluidic parameters can be used by most surgeons. Aspiration flow rates up to 40 ml/min and vacuum levels up to 400 mm Hg can be used routinely with an infusion bottle height of 130 to 140 cm. With these parameters, I have experienced no loss of efficiency.

Benefits of smaller incisions

The micro-coaxial ("ultra") infusion sleeve is the easiest sleeve to insert that I have ever seen in my 36 years of surgical experience. It is ultra-smooth and perfectly shaped to fit through the 2.1- to 2.4-mm incisions, and it normally seals with absolutely no leakage.

I can now have incision sizes that are customized for each patient. I currently use a 2.2-mm incision in approximately 85% of patients. With the 2.75-mm incision, a modest (0.25 to 0.50 D) flattening of the meridian is achieved, and many of my cataract patients benefit from this flattening. The 2.2-mm incision is truly astigmatically neutral, and I combine either incision size with a toric IOL and/or limbal relaxing incisions to achieve the desired refractive result.

For example, if a patient has 1.75 D of astigmatism with the steepest axis at 180°, I may create a 2.75-mm incision at 180° (thereby increasing the astigmatism to 2.0 D), and use a toric IOL (model T5, Alcon, which corrects 2 D of corneal astigmatism).

If a patient has 1.50 D of astigmatism with the steepest axis at 180° (or anywhere else), I will create the temporal incision with the 2.2-mm blade and insert a toric IOL (model T4, Alcon, which corrects 1.5 D of corneal astigmatism) at the steep axis. In other words, either I use the incision to alter the astigmatism so it is correctable with an available toric IOL (Alcon), or I perform micro-coaxial phaco to leave the corneal curvature unchanged if the astigmatism present can be fully corrected with a toric IOL.

Surgeons are familiar with manipulating the incision location and size either to affect the corneal curvature or not to affect the corneal curvature. The development of the micro-coaxial method has completely eliminated corneal curvature change, but that doesn't mean that surgeons always want to eliminate change. This system provides the flexibility to achieve a successful outcome in both cases.

Versatility of incision sizes

The system offers unsurpassed versatility. In addition to small-incision phacoemulsification, surgeons can use the high-infusion sleeve through a 2.75-mm incision, which it seals completely. With that sleeve and an infusion bottle height of 130 to 140 cm, I can use flow and vacuum levels that are previously unheard of-a flow rate of 60 ml/min and vacuum levels up to 760 mm Hg.

While these parameters certainly aren't for every surgeon, they are very valuable for softer lenses that can't be cracked or chopped. These lenses need to be aspirated, or drawn centrally, using these flow and especially these vacuum levels to obtain a purchase on them, and then they can be removed.