The newest addition to the Alcon line of pha- coemulsification machines is the Infiniti Vi- sion System (Alcon Laboratories Inc., Fort Worth, TX). The Infiniti offers three pha- coemulsification options including tradition- al ultrasound, NeoSoniX, and AquaLase (Fig.
22.1). NeoSoniX was originally introduced as an upgrade on the Alcon Legacy and provides the capability of delivering oscillatory sonic as well as axial ultrasonic energy, separately or in combination. The oscillatory motion in- volves small 2.0° arc excursions at a 100-Hz frequency. The addition of oscillatory move- ment improves surgeon control and occlu- sion management by constantly reposition- ing material on the phacoemulsification tip. It also enhances cutting performance, allowing for lower energy production with a resultant
lower risk for thermal injury and improved followability [1].
The Legacy and the Infiniti may be pro- grammed to initiate NeoSoniX at any desired level of ultrasound energy. It appears most ef- ficacious at 50% amplitude with a horizontal chopping technique in the AdvanTec burst mode at 50% power, 45 ml/min linear flow and 450 mmHg vacuum [1]. A 0.9-mm mi- croflare straight ABS tip rapidly impales and holds nuclear material for chopping. During evacuation of nuclear segments, the material flows easily into the tip, with very little ten- dency for chatter and scatter of nuclear frag- ments. With refinement of parameters, a 57%
reduction in average phacoemulsification power, and an 87% reduction in effective pha- coemulsification time have been reported [1].
The Infiniti Vision System
Mark Packer, Richard S. Hoffman, I. Howard Fine
CORE MESSAGES
2 NeoSoniX technology (Alcon) represents a hybrid modality involv- ing low-frequency oscillatory movement that may be used alone or in combination with standard high-frequency ultrasonic pha- coemulsification. Softer grades of nuclear sclerosis may be com- pletely addressed with the low-frequency modality, while denser grades will likely require the addition of ultrasound.
2 One of the most recent innovations in phacoemulsification has been the introduction of AquaLase to the Infiniti. Rather than using mechanical ultrasound energy from a vibrating phacoemulsifica- tion needle to emulsify lens material, the AquaLase handpiece uses heated pulses of balanced salt solution (57 °C) propelled from the tip at 50 Hz to strain and dissolve the lens for aspiration.
22
NeoSoniX has permitted further reduction in the application of ultrasonic energy to the eye when used in conjunction with ultra- sound, and allowed non-thermal cataract ex- traction when used alone. It represents an im- portant new modality in phacoemulsification technology.
One of the most recent innovations in pha- coemulsification has been the introduction of AquaLase to the Infiniti. Rather than using mechanical ultrasound energy from a vibrat- ing phacoemulsification needle to emulsify lens material, the AquaLase handpiece uses heated pulses of balanced salt solution (57°C)
210 M. Packer · R. S. Hoffman · I. H. Fine
Fig. 22.1. AquaLase phacoemulsification system
Fig. 22.2. Inside the AquaLase handpiece, 4-microliter fluid pulses are generated as current passes between electrodes.
The fluid pulses pass through a channel in the outer sleeve of the tip and then leave through a single small orifice positioned within the lumen of the needle
propelled from the tip at 50 Hz to strain and dissolve the lens for aspiration. Inside the AquaLase handpiece, 4-microliter fluid puls- es are generated as current passes between electrodes. The fluid pulses pass through a channel in the outer sleeve of the tip and then leave through a single small orifice posi-
tioned within the lumen of the needle (Figs.
22.2, 22.3 and 22.4).
AquaLase offers the advantage of eliminat- ing the risk of incisional burns and potential- ly reducing the risk for posterior capsule rup- ture.Another possible advantage of AquaLase would be the reduction of lens epithelial cells Chapter 22 The Infiniti Vision System 211
Fig. 22.3.
The AquaLase handpiece uses heated pulses of balanced salt solution (57°C) propelled from the tip at 50 Hz to strain and dissolve the lens for aspiration
Fig. 22.4. Comparison of ultrasound and AquaLase tips
(LECs) through mechanical dislodgment, with a potential resultant lower incidence of posterior capsule opacification [2]. If this be- comes a reality, the bimanual microincision approach to cataract extraction may be an ideal technique for AquaLase use, since all portions of the capsule fornices with their populations of LECs could be easily treated with the fluid pulses. Another means of ad- dressing LECs independent of the AquaLase system could entail the use of distilled-deion- ized water placed within a sealed capsule to lyse these cells [3].
Other features of the Infiniti include im- proved fluidics aided by an infusion pressure sensor and reduced system compliance by means of a rigid elastomeric membrane with- in the peristaltic design. Compared with the Alcon Legacy, the Infiniti has demonstrated reduced surge and better vacuum perform- ance with faster dynamic rise times yielding improved accuracy and response.
References
1. Fine IH, Packer M, Hoffman RS (2002) New phacoemulsification technologies. J Cataract Refract Surg 28:1054–1060
2. Mackool RJ, Brint SF (2004) AquaLase: a new technology for cataract extraction. Curr Opin Ophthalmol 15:40–43
3. Crowston JG, Healey PR, Hopley C et al (2004) Water-mediated lysis of lens epithelial cells at- tached to lens capsule. J Cataract Refract Surg 30:1102–1106
212 M. Packer · R. S. Hoffman · I. H. Fine
