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Bimanual microincision cataract surgery The growing awareness over the past year of both potential benefits and limitations of bimanual microincision cataract surgery has led to further development of new techniques and technology. Adoption of techniques using two incisions no wider than 1.4 mm and separation of infusion from aspiration and cataract removal should be slow and careful during their development phases. Smaller is not necessarily better. Depending on instrumentation, techniques and surgical experience, these bimanual microincision techniques can either increase or decrease safety and efficiency. Particularly since IOLs capable of being inserted through ultra small incisions are not yet optimally developed, safety and efficiency should be not be compromised. There has been continuing improvement in the control and modulation of energy, vacuum and fluidics. Ultrasonic phacoemulsification machines are increasingly designed to offer the best safety features of peristaltic systems and the best efficiency features of Venturi systems. For the cataract surgeon, in contrast to the vitreoretinal surgeon, the differences between the two basic pump types are progressively decreasing and both are now offering more similar flow rates and vacuum. These innovations are increasingly facilitating energy control to minimise thermal effects and maximise the desired mechanical impact without undesirable energy dispersal. High vacuum and flow can be used advantageously to decrease energy requirements. It is more difficult to achieve these high rates with bimanual microincision techniques than with coaxial phaco, but recent advances are enabling the use of higher rates than could be obtained previously. Rather than achieving the desired effect of increased stability of the anterior chamber, inadequate infusion during bimanual phaco can lead to chamber instability and intraocular decompression with complications such as posterior capsular breakage and corneal oedema. It is important to increase perfusion pressure sufficiently and use irrigation choppers that maximise flow rates. Recent designs with larger internal diameters and different opening locations permit better flow and maintenance of chamber stability. Hand-pieces recently modified for bimanual phaco are allowing better control of aspiration. Non-ultrasonic phacoemulsification technologies, such as low frequency, sonic pulses and oscillations and pulsed water jets are being developed to complement ultrasonic cataract removal. These non ultrasonic technologies cannot be used without ultrasound in denser cataracts. Laser cataract surgery may be used more frequently, if cost permits, as microincision cataract surgery is refined and adopted - and as intraocular lenses and injectable gels that can be inserted through microincisions smaller than 1.0 mm in width are developed.
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