Phaco FAQs

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  1. I have recently switched from the Alcon Infiniti system to the Centurion system. I have not changed anything about the creation of my clear corneal incisions - width, depth, blade configuration, or relationship of the entrance incision with the limbus. With the Centurion, however, I see quite a bit more iris prolapse through my CCI than I ever had with the Infiniti. I have tried reducing the IOP on the Centurion from its initial settings of 60mm Hg to as low as 40mm Hg, but that reduction does not seem to have much effect. Am I missing something? Does the sleeve direct flow differently than the Infiniti system did?
  2. To move from Infiniti to Centurion, what are the changes in the parameters that I need to setting in the centurion?
  3. Much of the world re-uses tubing. Any comments on how the US might move (safely) towards this? I am thinking in terms of pre case cost, with continued reduction of cataract surgery reimbursement. It seems the manufacturers and the FDA has us over a barrel.
  4. Does any of the panel have experience with phaco machines other than the big 3? (DORC, others)
  5. Do you ever do any MSICS/ECCE here in the US (for rocks, Coca-Cola cataracts, total cataracts)?
  6. I am new at phaco chop. I have trouble holding onto the nucleus without phacoing through it. What is the best setting for me?
  7. What would be a good chopper for me to use to get used to chopping?
  8. What modifications do you make to help prevent the immediate deepening and pain when you go into a highly myopic eye or post vitrectomized eye (post iris block) other than going under the iris and bringing it up once it happens?
  9. I still have difficulty evaluating "hardness" of nucleus pre-op. Any tips prior to getting phaco tip on nucleus?
  10. I believe I am seeing more retained corticonuclear chips the last few years. I suspect the etiology has to do with the settings related to OZIL. Have you seen an increased incidence of retained chips and can changing my setting be helpful?
  11. What are the merits of the 45 degree vs 30 degree and other phaco tip angles? Which is better for chopping or for bevel down phaco?
  12. What is a more effective strategy for surge protection, an ABS tip or flare tip?
  13. When the tip does not catch the nucleus when trying to impale during phaco chop, which is better, lower the phaco power or the vacuum or both? By what amount should I decrease the power?
  14. I face a problem in the high myopic patients. During cracking of the nucleus once I enter with the instrument the anterior chamber deepens and once I tried to crack infusion enter under iris and it suddenly is pushed against cornea. Do you have any tips regarding that issue?
  15. What are suggested settings for the AMO Whitestar Signature for a surgeon that employs the horizontal chop technique in the following situations: 1. "normal" density lens 2. Dense nuclear sclerotic cataract 3. "Slow mode" phaco. In addition, when would venturi be more beneficial? Would it be more helpful for a dense lens? If so, what are the suggested settings in this situation?
  16. Is flow ability (follow-ability) affected by EndoCoat or Viscoat?
  17. When do you use linear aspiration besides a post polar cataract?
  18. Pulse or burst – which uses less phaco energy? Could you please explain the use of pulse and burst modes?
  19. I use continuous flow so one less thing to think about – is that okay?
  20. How to avoid early capsular opacification?
  21. How does bottle height influence postop day one IOP?
  22. To phaco the last piece with safety, which parameter will be the one or the ones to change?
  23. Which are the advantages of using a 0.9 flare against a 1.1 phaco needle? And, if so, will my parameters have to change?
  24. For torsional ozil mode of phaco, which is the best needle?
  25. For very soft lenses what setting and technique do you prefer?
  26. I use Stellaris/Venturi with dense cataracts. The last piece often bounces away from the tip. What do I need to do to improve the grip?
  27. How do you phaco-chop a dense (4-5) cataract? What are you settings and machine?
  28. How and when does DM tear at the main wound occur and what do you do to avoid it?
  29. With my new Centurion machine, surge is minimized, but seems harder to remove cortex, which seems to be "plastering" to capsule.
  30. How do you manage when nucleus pops out of bag and into AC?
  31. Do you have any tips, tricks, caveats or other Pearls to share regarding the Dual Linear Foot Control concept? Is it worth the initial struggling, or is it better to let the machine do the driving for you?
  32. I would like to change my Infiniti settings to behave more "venturi-like" as far as the holding power is concerned, but without triggering a post-occlusion surge. Do you have any suggestions as my starting point parameters?
  33. What are the respective panel member's recommended settings for a) Hard/Brown Nuclei/Cataracts and b) when there is a Posterior Capsular Rupture, for the following machines: 1) Stellaris by B&L 2) Infiniti by Alcon 3) Centurion by Alcon?
  34. How does grade 3 or 4 on Infiniti change the flow, vacuum, and power settings?
  35. Any disadvantages of 100% torsional? Why not always use 100% torsional?
  36. When do you use hyper pulse & hyper burst?
  37. Does Ozil pulse give less corneal edema than ozil continuous?
  38. On Infiniti - is it better to increase aspiration/flow to hold the piece for chopping, or increase vacuum?
  39. Since torsional needs contact bur not occlusion with the nuclei, I personally use high flow rate. Such as 35-40, so I can aspirate the "nuclei dust" from the emulsification and low vacuum such as 150-200 mHg to avoid the un-emulsified fragments to get into the aspiration line. My question; What is the fundamental of high vacuum with this technology, and do you think this high vacuum can produce clogging of the aspiration line?
  40. Can the panel comment on variation of phaco tips? Advantages/disadvantages of sizes, angles, specialty tips, etc.?
  41. What are your preferred specific chop settings for the Centurion peristaltic machine? Would you suggest using torsional ultrasound for the initial impalement of the nucleus during the first chop?
  42. In the event of PCR when there are 1-2 nucleus pieces left, and after OVD and no vitreous in AC, if I want to proceed with phaco (Infiniti), what are the suggested phaco parameters to use?
  43. I am a quick chopper, with 20% of my cases now in FLACS. What are the parameters suggested to continue chopping in cases of lens fragmentation only with no softening? In my practice, the majority of cases are within Nuclear II to III in LOCUS II
  44. Regarding Infiniti machine, can you please suggest the settings for Sculpting and Segment Removal using Ozil combined with ultrasound for very dense cataracts?
  45. What parameters do you use for the Alcon Infiniti for "slow motion" Phaco during each phase of the surgery?
  46. How do you modify your settings on the Alcon Infiniti for a Flomax case?
  47. What settings and techniques do yo use for a vitrectomy with the Alcon Infiniti using both the 19 and 23 gauge vitrectors with the Pars Plana and Corneal approach, and what do you use for the split irrigation?
  48. I am at a new surgical center and find that I am getting corneal edema out of proportion to phaco power used, i.e. CDE always less than 15, postop IOP okay, but at least 2-3+ edema postop day one. Any suggestions for what parameters I should be paying attention to or modifying during surgery? I use continuous irrigation, that's the only thing I can think of; my phaco settings tend to be standard and I use divide and conquer.


1. I have recently switched from the Alcon Infiniti system to the Centurion system. I have not changed anything about the creation of my clear corneal incisions - width, depth, blade configuration, or relationship of the entrance incision with the limbus. With the Centurion, however, I see quite a bit more iris prolapse through my CCI than I ever had with the Infiniti. I have tried reducing the IOP on the Centurion from its initial settings of 60mm Hg to as low as 40mm Hg, but that reduction does not seem to have much effect. Am I missing something? Does the sleeve direct flow differently than the Infiniti system did?

The transition from Infiniti System to the Centurion system does require some adjustment in phaco settings on the machine. If you’re struggling with iris prolapse, though, my first recommendation would be to consider a smaller clear corneal incision. You don’t indicate what size you’re using. The phaco handpiece is safe in a 2.2mm wide incision (I have not had any experience with wound burn at this size), and at most I would recommend a 2.4mm incision. If you ensure a snug fit between your phaco handpiece and the clear corneal tunnel, the stability of your anterior chamber is much improved. You should notice improved stability of the lens-iris diaphragm during surgery, more efficient fluidics, and minimal iris movement. Do also check the sleeve fit and opening s on the sleeve that allow irrigation flow to make sure they are directed away from the cornea. Prior to removing the phaco or I/A handpiece, turn off your irrigation and even consider tapping the sideport incision to help prevent the iris from following instruments out of the eye. When transitioning from the Infiniti to the Centurion, you can increase your vacuum rate but this shouldn’t affect the rate of iris prolapse. If you see a lot of iris prolapse from IFIS, pseudoexfoliation, long eyes, or post-vitrectomized eyes, I would recommend a separate set of phaco settings on your machine with lower IOP, lower flow and aspiration rates, and an increased IOP ramp time.(Berdine Burger)

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2. To move from Infiniti to Centurion, what are the changes in the parameters that I need to setting in the centurion?

Generally, if you’re happy with your settings on the Infiniti you can keep many of them the same on the Centurion. The improved fluidics of the Centurion do allow for more aggressive settings – some people do like to increase the vacuum for improved efficiency while maintaining similar aspiration flow rates. If you use the balance tip, you may need to decrease your torsional amplitude significantly. (Berdine Burger, MD)

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3. Much of the world re-uses tubing. Any comments on how the US might move (safely) towards this? I am thinking in terms of pre case cost, with continued reduction of cataract surgery reimbursement. It seems the manufacturers and the FDA has us over a barrel.

Reusing aspiration tubing poses negligible infection risk because fluid is virtually always exiting, rather than entering the eye. In my opinion, this practice safely reduces the per-case cost, which is of critical importance if one is to offer phaco in the developing world. In the US, licensing regulations require that the ASC follow the manufacturers’ directions for use (DFU). When a manufacturer specifies that tubing is single use, then to not do so creates a regulatory liability. In the past, some manufacturers have offered the option of re-usable (autoclavable) tubing in the US. The AMO Diplomax was an example. Since moving to the cassette design, the major US phaco platforms no longer offer this option. Several phaco machines sold internationally outside the US offer the option of autoclavable tubing. (David F. Chang)

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4. Does any of the panel have experience with phaco machines other than the big 3? (DORC, others)

In the developing world, I have used the AMO Sovereign Compact and the Oertli portable phaco machine http://oertli-pharo.com/ Another excellent portable phaco machine is from Optikon http://www.optikon.com/ In These are not available in the US. My chapter outlines the phacodynamic principles that are applicable across all peristaltic phaco platforms. (David F. Chang)

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5. Do you ever do any MSICS/ECCE here in the US (for rocks, Coca-Cola cataracts, total cataracts)?

There are undoubtedly some situations where manual ECCE may be superior to phaco, but this will depend on the individual surgeon's own experience. With severe zonulopathy, ultrabrunescent nuclei, and Fuchs dystrophy, manual ECCE may better preserve endothelial cells and the posterior capsule - particularly if all 3 factors are present in the same eye. Most American surgeons from my generation learned large incision manual ECCE earlier in their careers, and would resort to this method when uncomfortable with phaco. In my experience, sutureless, manual small incision ECCE is more difficult to learn and unless a surgeon has already gained proficiency with this technique, such as in the developing world, they would not attempt this with the most difficult cases. For those that are comfortable with sutureless MSICS, I think it is a great method for some of the higher risk eyes that I described. (David F. Chang)

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6. I am new at phaco chop. I have trouble holding onto the nucleus without phacoing through it. What is the best setting for me?

Attaining a firm grasp of a nuclear quadrant or hemi-nucleus requires tip occlusion with accompanying high vacuum. With a peristaltic pump the vacuum provides the gripping force, and so one can consider raising the vacuum limit if a dense nuclear fragment keeps falling off the tip. In order for the vacuum to rise, the phaco tip must be occluded and with dense nuclear fragments, this requires a momentary burst of ultrasound to embed the tip opening within the nuclear tissue. With softer nuclei, using too much phaco power for this maneuver may cause the tip to eat all the way through the nucleus. Try reducing the phaco power, and also using just a momentary pulse or burst of ultrasound. With many machines, you can program burst mode to apply single bursts of phaco that are controlled with the foot pedal. This helps to prevent the “over-penetration” that you describe. (David F. Chang)

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7. What would be a good chopper for me to use to get used to chopping?

There are many excellent chopper designs to fulfill individual surgeon preferences. The Chang double ended combination choppers (I have no financial interest) were designed to provide both a horizontal and a vertical chopper on a single instrument. The blunt tipped Chang horizontal chopper is an elongated microfinger, with a thinner tip profile to facilitate cutting. At the opposite end, the Chang vertical chopper is like a Sinskey hook with a sharp point to facilitate penetration into brunescent nuclear material. One can switch from using this sharp vertical chopper to the horizontal chopper as nuclear fragments are brought into the supracapsular space. This enables horizontal sub-chopping of large fragments and protects the posterior capsule from ever contacting the sharper vertical tip as the epinucleus is aspirated. The finger shaped tip can also be used to engage and rotate the epinucleus counterclockwise with backhanded motions. The Seibel vertical chopper tip has the profile of a rounded blade. While the latter can vertically incise denser nuclear mass, there is no sharp point to come into contact with the posterior capsule. For this reason, transitioning surgeons often prefer the Chang horizontal/Seibel vertical chopper as their first combination chopper. (David F. Chang)

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8. What modifications do you make to help prevent the immediate deepening and pain when you go into a highly myopic eye or post vitrectomized eye (post iris block) other than going under the iris and bringing it up once it happens?

You are describing lens-iris diaphragm retropulsion syndrome (LIDRS). Bob Cionni showed that this is due to reverse pupillary block, where the iris circumferentially adheres to the anterior lens capsule upon introducing infusion into the anterior chamber. Unable to circulate behind the iris, the irrigation fluid hydrostatically propels the lens-iris diaphragm posteriorly, causing abrupt chamber deepening, extreme pupil expansion, and pain due to uveal stretching. It is likely to occur with highly myopic eyes, particularly if there has been a prior vitrectomy.

Once it occurs, the block can be broken by lifting the iris up off the lens capsule anywhere along the pupil margin. This allows irrigation fluid to circulate into the posterior chamber to equalize the hydrostatic pressure both anterior and posterior to the iris plane. This breaks the reverse pupillary block, and brings the lens-iris diaphragm forward to its physiologic position.

LIDRS is not only associated with abrupt pain, but also stretches the zonules. In addition, if the reverse pupillary block abruptly breaks during phacoemulsification, the pupil will suddenly constrict creating a pupil diameter that is often much smaller than it was preoperatively. Cionni hypothesized that this might be due to prostaglandin release caused by the excessive ciliary body stretching.

I agree that the best strategy is to anticipate and prevent LIDRS, rather than to react to it. To prevent LIDRS, one can insert the phaco tip into the OVD-filled anterior chamber while in foot position zero. Next, the surgeon lifts the iris in the contra-incisional nasal quadrant using the phaco tip before initiating inflow with foot position one [Fig 4]. Alternatively, one can simply lift the pupil edge with a second instrument before initiating irrigation inflow. Either maneuver can also be utilized following the onset of LIDRS to gradually break the reverse pupillary block. (David F. Chang)

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9. I still have difficulty evaluating "hardness" of nucleus pre-op. Any tips prior to getting phaco tip on nucleus?

Most surgeons categorize nuclei according to their firmness – soft, medium, or dense. As viewed through the slit lamp exam, as the color of the nucleus progresses from yellow to gold to brown, this correlates with increasing firmness and density. However, it is just as important to estimate the size of the endonucleus – small, medium, or large. For example, compared to a medium-sized nucleus, soft lenses will have a smaller diameter endonucleus that is not as thick. A proportionately thicker epinucleus surrounds the small endonucleus above and below, and on all sides. Chopping a small endonucleus is easier because of its reduced dimensions and the ample epinuclear space.

In contrast, the dimensions of brunescent endonuclei can range from small to medium to large. The size can also be determined at the slit lamp. In nuclear sclerotic cataracts, a golden or brunescent fetal nucleus is visible at the slit lamp, but the nucleus peripheral and anterior to it is pale yellow. This indicates an endonucleus of medium diameter and thickness, which is surrounded by a relatively normal sized epinucleus. However, there are nuclear sclerotic cataracts in which brunescence extends all the way forward to the anterior capsule when viewed at the slit lamp. This indicates a huge endonucleus with little to no epinucleus. Compared to the medium-sized endonucleus, it has both a larger diameter and a greater anterior-posterior thickness.

The key to differentiating these three endonuclear sizes at the slit lamp is to determine how far forward the brunescent color and opalescence extend from the fetal nucleus. Correctly anticipating the size of the endonucleus permits one to alter and adjust one’s technique. For example, with divide-and-conquer the sculpted trough must extend more peripherally and much deeper than usual in order to crack larger, denser nuclei. With chopping, the chopper and phaco tips must penetrate deeper than usual for a larger nucleus. Otherwise, the chop will be too superficial and will fail to divide it. (David F. Chang)

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10. I believe I am seeing more retained corticonuclear chips the last few years. I suspect the etiology has to do with the settings related to OZIL. Have you seen an increased incidence of retained chips and can changing my setting be helpful?

I don’t believe that the power modulation has anything to do with this. The factors predisposing to retained nuclear fragments are:

  • dispersive OVD (harder to evacuate from the angle)
  • brunescent nuclei (generates multiple tiny shrapnel-like fragments)
  • dense arcus senilis (obscures the angle)
  • smaller pupils (reduces fluidic current through the posterior chamber, making it easier for tiny pieces to get trapped there; in addition the iris compromises our view)
  • If one or more of these risk factors are present, my suggestions would be to take more time to thoroughly perform IA of the OVD, methodically I/A peripherally, and to irrigate with a BSS cannula through the chopper side port. There is always a small egress of fluid alongside the chopper shaft, and this outflow current will often draw tiny lens fragments to the port, where they get trapped and obscured by the arcus. (David F. Chang)

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    11. What are the merits of the 45 degree vs 30 degree and other phaco tip angles? Which is better for chopping or for bevel down phaco?

    The 45 degree bevel is more difficult to occlude because the tip opening has more surface area that is also oblong in shape. It has some advantages for sculpting deeply into a brunescent lens because you can still see the very tip of the more elongated bevel while it is being used at a steeper angle. For chopping – including bevel down phaco - I would recommend the 30 degree bevel because it is easier to occlude, and the reduced bevel angle facilitates “catching” incoming micro-particles of lens material. (David F. Chang)

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    12. What is a more effective strategy for surge protection, an ABS tip or flare tip?

    Both are effective strategies promoted by Alcon and can be used in combination. The mechanisms are quite different. If the question is “which is the more effective measure?” then it would be the flare tip. This is a way to reduce the internal diameter of the phaco tip without sacrificing too much tip surface area. This is because an identical vacuum level will provide much greater holding force when applied across a larger surface area. However, a smaller lumen diameter placed anywhere along the aspiration side serves as a flow restrictor. The smaller tip lumen is therefore one of the simplest and most effective ways to reduce post-occlusion surge. (David F. Chang)

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    13. When the tip does not catch the nucleus when trying to impale during phaco chop, which is better, lower the phaco power or the vacuum or both? By what amount should I decrease the power?

    Burst mode is able to deliver a single momentary pulse of phaco energy. Bursts can be delivered individually or in rapid succession, via surgeon foot pedal control. By embedding the tip without losing the surrounding tight seal, individual, successive bursts of phaco are ideal for impaling and gripping dense nuclear material for chopping. For impaling the nucleus during chop, “single” burst mode and high vacuum combine to provide a maximally strong purchase of the nucleus. Higher vacuum increases the holding power, which is important for chopping and for elevating the initial fragments out of the capsular bag. Since single burst mode needs to be set at a high fixed panel power for impaling dense nuclei, the power for burst mode should be lowered for soft-medium nuclei. Flow rate is less important because so little tissue is removed. (David F. Chang)

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    14. I face a problem in the high myopic patients. During cracking of the nucleus once I enter with the instrument the anterior chamber deepens and once I tried to crack infusion enter under iris and it suddenly is pushed against cornea. Do you have any tips regarding that issue?

    The lens iris diaphragm retro-displacement syndrome (LIDRS) is commonly encountered as soon as the irrigation fluid infuses the anterior chamber during phacoemsulsification in high myopes and in vitrectomized eyes. Robert Cionni used intraoperative endoscopy to prove that LIDRS is caused by reverse pupillary block as the iris becomes circumferentially pinned against the lens by the hydrostatic infusion pressure. Lifting the iris pupillary margin off of the lens with an instrument tip breaks the pupillary block and allows equilibration of the hydrostatic forces anterior and posterior to the iris.

    Although the pupil initially widens due to “hydro-mydriasis”, the excessive anterior chamber deepening from LIDRS causes sudden discomfort for patients under topical anesthesia and exerts significant traction on the zonules. Nuclear emulsification is more difficult with an excessively deepened anterior chamber because the instruments and phaco tip must approach the lens from a much steeper angle. If the reverse pupillary block abruptly breaks during phacoemulsification, the pupil will suddenly constrict creating a pupil diameter that is often much smaller than it was preoperatively.

    To prevent LIDRS, one can insert the phaco tip into the OVD-filled anterior chamber while in foot position zero. Next, lift the iris in the contra-incisional nasal quadrant using the phaco tip before initiating inflow with foot position one. Alternatively, one can simply lift the pupil edge with a second instrument before initiating irrigation inflow. Either maneuver can also be utilized following the onset of LIDRS to gradually break the reverse pupillary block. These steps allow irrigation fluid to circulate into the posterior chamber, thereby equilibrating the hydrostatic forces both in front of and behind the iris. The hydrostatically widened pupil will then gradually constrict as the pupillary block is broken. (David F. Chang)

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    15. What are suggested settings for the AMO Whitestar Signature for a surgeon that employs the horizontal chop technique in the following situations: 1. "normal" density lens 2. Dense nuclear sclerotic cataract 3. "Slow mode" phaco. In addition, when would venturi be more beneficial? Would it be more helpful for a dense lens? If so, what are the suggested settings in this situation?

    Signature settings are for 2.2 mm incision, 0.7 mm phaco needle with gold sleeve from MicroSurgical Technology, Redmond, WA. Different sized incisions, phaco needle, sleeve will likely require modification of these settings. (Download PDF)

    Signature settings for a normal density cataract, horizontal chop:
    Sculpt: Aspiration, panel: 25 cc/min
    Vacuum, panel: 50 mm Hg
    Power, Ellips continuous, linear: maximum 40%
    Bottle height: 70 cm
    Impale: Aspiration, panel: 28 cc/min
    Vacuum, panel: 500 cc/min
    Power, linear, Ellips continuous with two 150 msec pulses/sec: maximum 25%
    Bottle height: 100 cm
    Ellips: Occlusion mode phaco is used to decrease the aspiration rate when a specific vacuum level is reached, to reduce surge.
    Chamber Stabilization Environment (CASE) is used to regulate vacuum with occlusion, to reduce surge.
    Aspiration, panel, unoccluded: maximum flow 35 cc/min
    Aspiration, panel, occluded: maximum flow 10 cc/min when vacuum reaches 350 mm Hg
    Vacuum, panel: maximum 450 mm Hg
    Up threshold vacuum: 425 mm Hg, timer starts which keeps vacuum at 425 – 450 mm Hg for preset up time based on surgeon preference, 800 msec
    After up time of 800 msec, vacuum drops down to preset surgeon preference case value of 400 mm Hg
    Power, linear, Ellips continuous with six 150 msec longitudinal pulses; unoccluded maximum 30%, occluded maximum 40%
    Bottle height: 106 cm
    Epinucleus: Occlusion mode phaco is used.
    Aspiration, linear unoccluded: 32 cc/min
    Aspiration, linear occluded: 16 cc/min when vacuum reaches 145 mm Hg
    Vacuum, linear: maximum 375 cc/min
    Power, linear, Ellips, continuous unoccluded: 10%
    Power, linear, occluded: 10%
    Bottle height: 95 cm
    Cortex: Aspiration, linear: 30 cc/min
    Vacuum, linear: 500 mm Hg
    OVD: Aspiration, linear: maximum 50 cc/min
    Vacuum, panel: 600 mm Hg

    Signature settings for a dense cataract:
    Sculpt: Aspiration, panel: 25 cc/min
    Vacuum, panel: 50 mm Hg
    Power, linear Ellips, continuous: 50%
    Bottle height: 70 cm
    Impale: Aspiration, panel: 28 cc/min
    Vacuum, panel: 500 cc/min
    Power, linear, Ellips continuous with two 150 msec pulses/sec: maximum 30%
    Bottle height: 100 cm
    Ellips: Occlusion mode phaco is used to decrease the aspiration rate when a specific vacuum level is reached, to reduce surge.
    Chamber Stabilization Environment (CASE) is used to regulate vacuum with occlusion, to reduce surge.
    Aspiration, panel, unoccluded: maximum flow 30 cc/min
    Aspiration, panel, occluded: maximum flow 20 cc/min when vacuum reaches 425 mm Hg
    Vacuum, panel: maximum 525 mm Hg
    Up threshold vacuum: 500 mm Hg, timer starts which keeps vacuum at 500 – 525 mm Hg for preset up time based on surgeon preference, 800 msec
    After up time of 800 msec, vacuum drops down to preset surgeon preference case value of 475 mm Hg
    Power, linear, Ellips continuous with six 150 msec longitudinal pulses; unoccluded maximum 30%, occluded maximum 30%
    Bottle height: 106 cm
    Epinucleus: Same as for standard density nucleus using horizontal chop
    Cortex: Same as for standard density nucleus using horizontal chop
    OVD: Same as for standard density nucleus using horizontal chop

    Signature settings for slow motion IFIS:
    Sculpt: Same as for standard density nucleus using horizontal chop
    Impale: Aspiration, panel: 25 cc/min
    Vacuum, panel: 460 cc/min
    Power, linear, Ellips continuous with two 150 msec pulses/sec: maximum 25%
    Bottle height: 100 cm
    Ellips: Occlusion mode phaco is used to decrease the aspiration rate when a specific vacuum level is reached, to reduce surge.
    Chamber Stabilization Environment (CASE) is used to regulate vacuum with occlusion, to reduce surge.
    Aspiration, panel, unoccluded: maximum flow 30 cc/min
    Aspiration, panel, occluded: maximum flow 10 cc/min when vacuum reaches 350 mm Hg
    Vacuum, panel: maximum 400 mm Hg
    Up threshold vacuum: 375 mm Hg, timer starts which keeps vacuum at 375 – 400 mm Hg for preset up time based on surgeon preference, 800 msec
    After up time of 800 msec, vacuum drops down to preset surgeon preference case value of 360 mm Hg
    Power, linear, Ellips continuous with six 150 msec longitudinal pulses; unoccluded maximum 30%, occluded maximum 40%
    Bottle height: 106 cm
    Epinucleus: Same as for standard density nucleus using horizontal chop
    Cortex: Same as for standard density nucleus using horizontal chop
    OVD: Same as for standard density nucleus using horizontal chop

    Venturi pump:
    The practical difference of a Venturi pump versus a peristaltic pump is followability at low vacuum levels. The Venturi pump does not require occlusion to build vacuum. Therefore, distal and proximal followability for removal of chopped nuclear fragments is improved. Flow and vacuum will bring chopped nuclear fragments to the phaco tip. Venturi fluidics allows cortex to flow into the phaco tip at a low vacuum and does not require occlusion to build vacuum for aspiration. With a Venturi pump, vacuum can usually be reduced to 275 – 300 mm Hg. Occlusion mode phaco and the Chamber Stabilization Environment (CASE) are not Venturi functions
    Venturi pump: OVD: Same as for standard density nucleus using horizontal chop

    David Chang, MD: Venturi tends to speed up the pace and for phaco is often preferred for surgeons doing supracapsular phaco (e.g. lens tilted up). You may sacrifice some safety when the posterior capsule is more exposed (e.g. last fragments remaining) because the posterior capsule is more easily aspirated. Peristaltic pump users can emulate Venturi fluidics for certain steps by increasing the aspiration flow rate. (Ken Cohen)

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    16. Is flow ability (follow-ability) affected by EndoCoat or Viscoat?

    Each ophthalmic viscoelastic device, OVD, has unique properties determined by the length and concentration of the molecules, and follow-ability is affected by any OVD. OVDs are peculiar fluids that take up space and occupy the physical boundary between fluids and solids. It is this space occupying effect that inhibits follow-ability. Viscoelastic properties differ between OVDs, and these properties affect the ability to occupy space during stress, flow into the eye. The greater the ability to remain in the eye under stress, more space occupying ability, then the greater the inhibiting effect on follow-ability.

    Dr. Steve A. Arshinoff classified OVDs according to their cohesive-dispersive indies, CDI. The CDI indicates the ease for removal relative to vacuum level, % aspirated/ mm Hg. Viscoat and presumably Healon EndoCoat have low CDIs, meaning that high vacuum levels are required for removal, and removal takes longer than for OVDs with higher CDIs, i.e. Healon GV. Healon EndoCoat and Viscoat take on average 149 seconds and 134 seconds to remove, respectively.

    What does this mean for follow-ability? OVDs with low CDIs occupy space and partition intraocular contents and tend to stay in the eye with flow. Therefore, OVDs with low CDIs inhibit follow-ability more than OVDs with higher CDIs. (Ken Cohen)

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    17. When do you use linear aspiration besides a post polar cataract?

    To increase safety, I recommend a linear aspiration flow rate, cc/min, when dealing with any soft cataract. The aspiration flow rate affects mostly distal follow-ability. To protect the peripheral capsule and zonules and the posterior capsule, the surgeon wants to avoid sudden aspiration and emulsification of a soft lens. Because a soft lens can tend to stick together, to enhance follow-ability the phaco aspiration port must be placed close to the lens material. Therefore, to prevent damage to adjacent structures, precise control is necessary. This control is provided by a linear aspiration flow rate in foot pedal position 2. (Ken Cohen)

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    18. Pulse or burst – which uses less phaco energy? Could you please explain the use of pulse and burst modes?

    Phaco burst mode uses less energy than phaco pulse mode because the surgeon can control emulsification and proximal follow-ability with linear control of the on and off time of the energy bursts, duty cycle, in foot pedal position 3.

    Pulse mode is a basic power modulation in which energy is delivered in pulses rather than continuously. For traditional pulse phaco, the surgeon sets the length of time for each pulse to be on, and the pulse is on and off for an equal amount of time. Thus, no matter the length of the pulse, the duty cycle is fixed at 50%, the ratio of phaco power on-time to total time, on time plus off time. The duty cycle is constant no matter the location of the foot pedal in position 3. The amount of phaco power is linearly controlled in foot pedal position 3. However, now phacoemulsifiers allow pulse mode with duty cycles other than 50%, as the surgeon choses, but the duty cycle is still fixed in foot pedal position 3.

    Burst mode provides more control of delivered phaco energy than pulse mode. The surgeon sets the length of the energy burst and the minimum off time between each burst. As the foot pedal is depressed in position 3, the duty cycle varies. The time between each burst gets shorter as the foot pedal is depressed in position 3, with the limit being the preset minimum time when the foot pedal is depressed completely in position 3. Therefore, burst mode provides linear control of the duty cycle, generally using fixed phaco power. As the foot pedal is depressed in position 3, the duty cycle increases. Also, with burst mode, phacoemulsifiers now allow for linear control of phaco power in foot pedal position 3, in addition to control of the duty cycle.

    What is the clinical relevance for the surgeon? Power modulation, bursts, allows for use of less phaco energy and improves efficiency of emulsification, because proximal follow-ability is better. The use of shorter off time with linear depression of the foot pedal in position 3 results in less time for repulsion of the nuclear pieces, and allows flow and vacuum to hold the nuclear pieces on the phaco tip. Emulsification proceeds more efficiently, with less chatter. (Ken Cohen)

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    19. I use continuous flow so one less thing to think about – is that okay?

    In most circumstances continuous in-flow, constant irrigation is safe to use. Continuous in-flow stabilizes the anterior chamber and maintains IOP. There are situations in which constant irrigation might not be safe. If there is a tear in the posterior capsule and/or instability of the zonules, or even a radial tear in the capsulorhexis, continuous in-flow might not be safe. Once the intraocular structures are stabilized with a dispersive OVD, the surgeon might want to use slow motion phaco. The bottle height is decreased along with deceasing the aspiration flow rate, cc/min, and the maximum vacuum, mm Hg. In these situations, at insertion of the phaco tip, the dispersive OVD is maintaining the anterior chamber. Continuous irrigation at insertion of the phaco tip, might increase the IOP to a level such that there could be added insult to the already compromised anatomy. (Ken Cohen)

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    20. How to avoid early capsular opacification?

    Early opacification of the posterior capsule can be minimized by removal of the lens cortex. A major advance for effective removal of cortex is cortical cleaving hydrodissection as described by I. Howard Fine, MD. The hydrodissection fluid wave is seen, and the nucleus moves anteriorly. The nucleus is then gently pushed posteriorly, forcing the fluid between the capsule and the cortex. Thus, the cortex is cleaved from the capsule, allowing easier removal of cortex in large sheets. Depending on how much cortex remains on the posterior capsule, polishing the posterior capsule, using low flow and low vacuum, may delay early opacification.

    Placement of the IOL in the bag and the size of the capsulorhexis play a role. The edge of the capsulorhexis should overlap the IOL optic by 0.5 mm. This promotes a physical barrier to cellular proliferation. The IOL optic is pushed posteriorly against the posterior capsule, and the peripheral anterior and posterior capsules can adhere, forming a physical barrier, isolating peripheral lens epithelial cells, the “shrink-wrap” phenomenon.

    Another important factor is IOL geometry. A square posterior edge of the optic acts as another physical barrier to lens proliferation causing posterior capsule opacification. (Ken Cohen)

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    21. How does bottle height influence postop day one IOP

    Bottle height does not directly influence postop day one IOP. It is likely that the amount of OVD left in the eye at the conclusion of surgery and the patient’s predisposition to glaucoma do affect the IOP on day one. Therefore, to remove OVD at the conclusion of surgery, the bottle height should be high enough to provide an effective differential in pressure between the IOP and the aspiration line so that flow and unoccluded vacuum removes the OVD from the eye. (Ken Cohen)

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    22. To phaco the last piece with safety, which parameter will be the one or the ones to change?

    One is performing carouseling phaco, during which the phaco tip is intermittently occluded. The goal is to minimize chatter. The parameter to adjust is flow, cc/min. Increasing the flow rate will keep the nuclear fragment on the phaco tip, reducing chatter when phaco breaks occlusion and vacuum decreases. (Ken Cohen)

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    23. Which are the advantages of using a 0.9 flare against a 1.1 phaco needle? And, if so, will my parameters have to change?

    The flare tip doubles the size of the opening compared to the standard tip. The formula: opening area x vacuum = holding force. Thus the larger the opening area, when occlusion occurs, creates more holding force for a given level of vacuum than with a smaller tip. The same reasoning would apply to a standard 1.1 mm tip compared to a standard 0.9 mm tip. The flare tip has a narrowed shaft. This narrowed shaft allows increased resistance and therefore vacuum for holding a nuclear piece. The greater holding force should by itself allow ultrasound to be more efficient. There is no need to change parameters. More lens material can be emulsified with the same flow rate and vacuum. The narrowed shaft of the 0.9 mm flare tip, will create increased unoccluded vacuum due to more resistance in the outflow system. This promote proximal followability during emulsification, also resulting in less chatter. (Ken Cohen)

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    24. For torsional ozil mode of phaco, which is the best needle?

    For torsional ultrasound to be effective, a bent tip is necessary. Torsional ultrasound rotates the phaco tip at the incision. This small rotation at the incision is amplified with a side-to-side motion at the tip. The side-to-side motion causes a shearing effect on the nucleus. If the phaco tip were straight, then the action would be similar to coring an apple because the side-to-side motion would not occur, and nuclear material would not be sheared and emulsified. (Ken Cohen)

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    25. For very soft lenses what setting and technique do you prefer?

    For very soft lenses my preferred technique is having complete control over all parameters, phaco power %, flow rate cc/mm, and vacuum mm Hg. All parameters under linear control with the foot pedal. Also, I use a modified “flip and chip” technique as described by I. Howard Fine, MD. Cortical cleaving hydrdissection is performed followed by hydrodelineation. Hydrodelineation separates the small, firmer but still soft nucleus, from the large, soft epinucleus. The large, thick epinucleus keeps the capsular bag on stretch and protects the capsule. The corneal endothelium is also protected because the small nucleus is removed from inside the epinucleus.

    After hydrodissection and hydrodelineation, a central groove in the nucleus is sculpted. Because the lens is soft, the golden ring is used as a marker. Care is taken to not extend the groove past the golden ring, the junction of the nucleus and epinucleus. The groove does not have to be deep, just deep enough so that the soft nucleus will fold inward on itself. The folding is assisted by gentle separation and cracking of the groove using a flat second instrument, such as a Drysdale nucleus manipulator which has a flat, paddle-shaped tip. Complete cracking is not necessary. Standard sculpting parameters are used, with linear control of phaco power, aspiration fixed at 25 cc/min, vacuum fixed at 195 mm Hg, and power linear at 0% – 50 %.

    The next step is the key to removal of soft lenses. The same parameters are used to remove in sequence the nucleus and then the epinucleus, aspiration linear at 15 cc/min – 25 cc/min, vacuum linear at 150 mm Hg – 350 mm Hg, and power linear at 0% - 10%. The nucleus is rotated into position so that one-half can be accessed and aspirated and emulsified. One should take time and not depress the foot pedal too much so the the soft nucleus will aspirate gently into the phaco tip. The soft nucleus will fold onto itself. Then, the remaining nucleus should be rotated into position for similar aspiration and emulsification as necessary. There may be a remaining nuclear plate that will either flow up into the phaco tip or can be lifted up with the second instrument. Using the same parameters, the epinucleus is aspirated and emulsified as needed. Again, this should not be rushed, and observation of aspiration will tell the surgeon how much to depress the foot pedal. Phaco power may not be necessary. Only the anterior rim of the epinucleus should be aspirated. After trimming one area of the epinucleus, the epinucleus should be rotated to allow access to an area with a remaining anterior rim. Eventually, enough epinucleus will be aspirated so that there is sufficient room for the soft epinucleus to flip and tumble into the pupil for final removal. With this “chip and flip” technique, it is likely that most of the cortex will be aspirated with the epinucleus. (Ken Cohen)

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    26. I use Stellaris/Venturi with dense cataracts. The last piece often bounces away from the tip. What do I need to do to improve the grip?

    The reasons for a loose fragment to bounce off the tip can vary. Sometimes the outflow pathway can be obstructed with pieces of the dense nucleus. It is important to ensure that the handpiece and tubing are free and clear before proceeding. If this is not the problem, the easiest solution when using the Stellaris is turning on Waveform. This will eliminate any possible chatter. Waveform uses less power than traditional ultrasound so it helps if you increase the power by 5% and the Duty cycle by 15%. A mid range pulse rate of 60 pulse per second can be used as well.

    Q. What about Centurion?

    With a peristaltic pump, occlusion of the tip must occur before vacuum can build. Therefore, ensure that the lens fragment is completely occluding the tip. The vacuum must also build sufficiently before applying power. Using a Balanced tip can be helpful as it may be more effective at the lower powers. Other actions include increasing the foot position # 2 excursion to make it longer and thereby decreasing the possibility of inadvertently going into foot position #3. Increasing the vacuum level in foot position 2 to a higher level than foot position #3 can also be tried. (Bonnie An Henderson)

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    27. How do you phaco-chop a dense (4-5) cataract? What are you settings and machine?

    Entire book chapters have been written to answer the question of how to phaco-chop a dense cataract so I may not be able to give a complete answer in this paragraph. However, the important concept is to alter the settings to increase the holding power with sufficient vacuum, increase the power energy to cut through a dense cataract, and allow sufficient inflow of fluid to keep the chamber stable, dissipate the heat, and bring the fragments of lens pieces toward the phaco tip.

    For the Stellaris: use the Waveform settings and increase power in the Segment removal settings. An example would be bottle height of 135cm, power 60, vacuum of 290, pulse per second 70, duty cycle of 60%.

    For the Centurion: Similar settings for the Infiniti can be used with the Centurion. An example of dense chop settings would be a power of 40, vacuum of 400, aspiration of 35. Torsional IP is recommended which will mix in traditional ultrasound to the torsional ultrasound when needed. (Bonnie An Henderson)

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    28. How and when does DM tear at the main wound occur and what do you do to avoid it?

    A descemet’s tear usually occurs during the introduction of a cannula or phaco tip or during IOL implantation. However, it can happen at any stage when something is introduced into the eye. Therefore, the first important step to prevent the creation of the tear is by ensuring that the entrance through the incision is complete before injecting (fluid or viscoelastic solution or IOL). The best way to ensure that the entrance is completely through the cornea and into the anterior chamber is to watch the subtle change in color of the inserted instrument. When it is still in the cornea, the color is slightly muted due to the corneal tissue. Once the instrument is completely inserted into the anterior chamber, the color becomes darker and closer to the actual hue. Once a tear has occurred, it is important to recognize it early in order to prevent further propagation.

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    29. With my new Centurion machine, surge is minimized, but seems harder to remove cortex, which seems to be "plastering" to capsule.

    This may be due to the target IOP. Since the IOP is actively maintained in the Centurion, if the IOP is too high, this could cause the cortex to appear to be “plastered” to the capsule. Try lowering the target IOP. Also, since the internal diameter of the aspiration tubing is smaller, it may require a higher aspiration rate than the rate used on the Infiniti to elicit better attraction of cortical material. (Bonnie An Henderson)

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    30. How do you manage when nucleus pops out of bag and into AC?

    The management of this situation depends on the surgeon’s lens removal technique. While many surgeons prefer to remove the lens in the capsular bag (divide and conquer or chop techniques), some prefer to prolapse the lens out of the bag with a supracapsular approach.

    If choosing to keep the lens in the AC, injecting a layer of dispersive viscoelastic to coat the endothelial layer of the cornea is beneficial. Use the high vacuum setting (quadrant removal settings rather than sculpt setting) and hold onto the lens with phaco while using a chopper to section the lens into smaller fragments that can be aspirated. If the surgeon is not comfortable using a chopper, it is fine to use the phaco to slowly groove away layers of the lens. Often, the lens will pop back in the bag once it has been de-bulked. Once back in the bag, the lens can then be removed in the technique that is the most familiar to the surgeon. (Bonnie An Henderson)

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    31. Do you have any tips, tricks, caveats or other Pearls to share regarding the Dual Linear Foot Control concept? Is it worth the initial struggling, or is it better to let the machine do the driving for you?

    I agree that there is a learning curve with the dual linear foot pedal. In my practice of 30 ophthalmologists (@ 12 cataract surgeons), only 2 use the dual linear function routinely. I believe this is due to the learning curve. The surgeons who use it regularly feel strongly that the benefits of decoupling vacuum from ultrasound outweigh the struggles of the temporary learning phase. Here are some tips in implementing the dual linear foot pedal. The placement of the foot onto the pedal and the position of the pedals underneath the stretcher are important variables in becoming comfortable with dual linear control. Find the perfect position of the foot pedals (both the phaco foot pedal and the microscope pedal) under the stretcher. Once the perfect positions are found, outline the pedals onto the floor of the operating room so that every time a new case starts, the pedals can be placed exactly in those perfect positions. Practice placing the foot squarely in the center of the phaco foot pedal so that the foot can easily move horizontally to control the “Yaw” function. Practice engaging in the horizontal position before fully pressing on the vertical pitch to engage ultrasound cutting capabilities. This is usually done in cases with soft cataracts where holding onto the pieces can be more difficult and therefore being able to engage in ultrasound before achieving the maximum vacuum can customize the control of the removal of the fragment. (Bonnie An Henderson)

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    32. I would like to change my Infiniti settings to behave more "venturi-like" as far as the holding power is concerned, but without triggering a post-occlusion surge. Do you have any suggestions as my starting point parameters?

    Altering Infiniti settings to simulate Stellaris behavior:
    To simulate venturi-like performance with the Infiniti, I would recommend LINEAR control of the vacuum with a FIXED aspiration speed to make the flow quick and then add the responsiveness with a Dynamic Rise (Infiniti) of 1,2, or 3). Dynamic rise increases the pump instantaneously prior to occlusion to more quickly build vacuum. Incidentally, the holding power of a Peristaltic can be as strong or stronger than a Venturi; it is a matter of settings. Increasing the ASPIRATION rate to Fixed 45 cc /min and a VACUUM of Linear 250-475 mm/hg would perform admirably with a Bottle height of 110 or higher (Extender needed on Infiniti).

    Keep in mind that in peristaltic systems (Infiniti/Centurion), vacuum begins to build upon occlusion of the tip, while with a Venturi, vacuum is engaged in position 2 of the foot pedal, even when there is no material at the tip. (Bonnie An Henderson)

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    33. What are the respective panel member's recommended settings for a) Hard/Brown Nuclei/Cataracts and b) when there is a Posterior Capsular Rupture, for the following machines: 1) Stellaris by B&L 2) Infiniti by Alcon 3) Centurion by Alcon

    Hard/Brown Nuclei Cataracts
    Stellaris:
    Bottle Height – 135 cm
    Power – 60
    Vacuum – 290
    Pulse per second
    0, Duty Cycle 60%

    Infiniti:
    50 Phaco Power Linear control,
    20% on-time
    20-40 pulses per second
    100 Linear Ozil,
    80% on-time
    (Utilizing pulse that incorporates the repulsion of traditional phaco in order to clear the tip of the pulverized material created by Torsional is ideal. Increasing the vacuum is not needed with Torsional.)

    Centurion: Reduce these energy parameters above by 20-30%.

    Posterior Capsular Rupture
    Stellaris:
    Bottle Height – 50-75cm
    Power – 40
    Vacuum – 35
    Pulse per second–5-70 (depending on density)
    Duty Cycle – 50%

    Infiniti:
    Lower the irrigation and aspiration between 20 to 25%,
    Bottle Height – 55 to 80cc
    Power – 40
    Vacuum – some argue for low vacuum (linear control 25-30), while some would argue for high settings to increase holding power to emulsify a fragment (linear control 250). Choosing the right approach depends on the situation. If a vitrectomy has already been performed, then higher vacuum settings may be more appropriate since there is a much lower risk of holding onto vitreous. Flow – 28 (lower to decrease turbulence)

    Centurion: similar to Infiniti but with IOP of 40-50
    (Bonnie An Henderson)

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    34. How does grade 3 or 4 on Infiniti change the flow, vacuum, and power settings?

    Actually there are 4 slots under which you can save settings – these are not pre-set, but are customized per your preference. Many surgeons use only 2 of these 4 slots, with 1 or 2 for softer nuclei and 3 or 4 for harder nuclei. (Lisa Park)

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    35. Any disadvantages of 100% torsional? Why not always use 100% torsional?

    I use 100% torsional on a linear setting, which means that the more I press the footpedal in position 3, the more power I get. When I encounter a harder nucleus, I tend to add traditional longitudinal phaco power. Some people feel that when longitudinal movement is combined with torsional movement that fragments can be repelled, resulting in less efficient phaco. (Lisa Park)

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    36. When do you use hyper pulse & hyper burst?

    Both are power modulations that enable one to decrease use of phaco energy in order to protect the corneal endothelium, especially in very dense cataracts.

    Hyperpulse allows the surgeon to exceed 100 pulses per second (compared with traditional pulse, which had a maximum of 20 pulses per second).

    Hyperburst technology allows you to use burst durations as short as 4 ms (compared with traditional burst, which had a minimum of 80 ms).

    I personally do not use burst, because this setting does not allow for linear control of ultrasound power.

    I do believe the hyperpulse can be an effective way to decrease total phaco energy without compromising efficiency. (Lisa Park)

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    37. Does Ozil pulse give less corneal edema than ozil continuous?

    Yes, Ozil pulse should yield less corneal edema, since there is time off for the phaco between the pulses. (Lisa Park)

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    38. On Infiniti - is it better to increase aspiration/flow to hold the piece for chopping, or increase vacuum?

    To hold onto the piece for chopping, I increase vacuum, which occurs when the phaco tip is occluded. Increasing aspiration / flow tends to speed up the rate at which pieces come toward the tip, when it is not occluded. (Lisa Park)

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    39. Since torsional needs contact bur not occlusion with the nuclei, I personally use high flow rate. Such as 35-40, so I can aspirate the "nuclei dust" from the emulsification and low vacuum such as 150-200 mHg to avoid the un-emulsified fragments to get into the aspiration line. My question; What is the fundamental of high vacuum with this technology, and do you think this high vacuum can produce clogging of the aspiration line?

    I believe the answer depends on surgical technique. For phaco chop, one needs to have good purchase, to hold on a nuclear fragment. This is best achieved with high vacuum, which builds once the tip is occluded. Once the chop has been completed, then phaco energy is used to emulsify the piece. The use of high vacuum itself should theoretically not clog the aspiration line, because pieces that are not adequately emulsified will simply not enter the phaco tip. (Lisa Park)

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    40. Can the panel comment on variation of phaco tips? Advantages/disadvantages of sizes, angles, specialty tips, etc.?

    There are many variations on the phaco tip;

    Size: these currently range from about 19 gauge to 20 and 21 gauge. The advantage is that a smaller tip can go through a smaller incision. The compromise is that not as much material can enter the tip, making the procedure slower.

    Angulation: This refers to the angle of the bevel – 0, 30, or 45 degrees. The more angled the tip, the larger the opening for fragments to enter during phaco. The compromise is that the surface area to achieve full occlusion is larger, requiring the surgeon to be aware of this when trying to achieve good purchase on fragments. (Lisa Park)

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    41. What are your preferred specific chop settings for the Centurion peristaltic machine? Would you suggest using torsional ultrasound for the initial impalement of the nucleus during the first chop?

    On the Centurion:
    For sculpt
    IOP 70, bottle height 95
    Vacuum 95 fixed
    Asp 23, fixed
    Torsional phaco 60, linear

    For quadrant removal
    IOP 80, bottle height 109
    Vacuum 425, fixed
    Asp 32, fixed
    Torsional phaco 60, linear

    For epinuclear removal
    IOP 80, bottle height 109
    Vacuum 380, with a small initial linear component
    Asp 30, with a small initial linear component
    Torsional phaco 60, linear

    Cortical cleanup
    IOP 90, bottle height 122 (I use bimanual IA)
    Vacuum 575, linear
    Asp 28, fixed

    Viscoelastic removal (I am using cohesive OVD to insert the IOL)
    IOP 100, bottle height 136
    Vacuum 650, linearc Asp 50, linear

    Regarding settings for initial quadrant removal, if I am interpreting correctly your question, gaining purchase on the first quadrant can be challenging with the Centurion, which has extremely effective cutting ability. A few parameters that I have adjusted include raising the vacuum; with the active fluidics this machine can do so with amazing safety. I will also use add a small initial linear ramp up component to the vacuum and aspiration which helps to gain purchase before emulsifying. I do not turn off the torsional, simply because of the logistics of turning it off and on, but it sounds like a great option to remove the initial piece. (Lisa Park)

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    42. In the event of PCR when there are 1-2 nucleus pieces left, and after OVD and no vitreous in AC, if I want to proceed with phaco (Infiniti), what are the suggested phaco parameters to use?

    The main parameter that I change is to lower the bottle height from 110 to about 90 (or change the IOP) in order to prevent hydrating the vitreous. To continue phaco, I then lower the vacuum and asp to my epinuclear settings which still allows me to grab pieces with less fluidic turbulence. (Lisa Park)

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    43. I am a quick chopper, with 20% of my cases now in FLACS, what are the parameters suggested to continue chopping in cases of lens fragmentation only with no softening...as I hate excess air bubbles and impaired visibility associated with fragmentation. In my practice, the majority of cases are within Nuclear II to III in LOCUS II

    I like the Balanced Tip when using OZIL. (Keith Walter)

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    44. Regarding Infiniti machine, can you please suggest the settings for Sculpting and Segment Removal using Ozil combined with ultrasound for very dense cataracts?

    Adding longitudinal ultrasound to torsional is often a must for brunescent lenses. While the Ozil torsional is great, very dense lenses can require longitudinal motion to cut more effectively. I do use a chop technique, which can certainly decrease energy use. Alcon also has the ultra chopper, which could be helpful to pre-chop the pieces in order to decrease energy use for the dense lenses, although I do not have much experience with this. Bob Cionni, current ASCRS president, has extensive experience with the Ultra Chopper piece for the Infiniti. Also, using a pulse or burst mode in the chop/quad settings can be helping to most efficiently disassemble the nucleus. On a final note, I have used Legacy, Infiniti and Centurion. There is a huge improvement with the Centurion over the Infiniti for nuclear disassembly. Corneas certainly look clearer with more dense lenses. (Elizabeth Yeu)

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    45. What parameters do you use for the Alcon Infiniti for "slow motion" Phaco during each phase of the surgery?

    Slow Motion Phaco on Alcon Infiniti:
    I generally maintain the same settings for any cases that are suspicious for requiring a “slower motion” in the eyes, i.e. post-TPPV, Flomax, refractive lens exchange. Once I am in the eye I will make necessary adjustments. In general, decreasing the aspiration rate in the chop/quad and I/A settings will reduce how quickly pieces are moving or how much the phaco needle is disassembling the nucleus. Here are a few suggestions for values for adjusting routine settings. (Elizabeth Yeu)

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    46. How do you modify your settings on the Alcon Infiniti for a Flomax case?

    Settings on the Alcon Infinity for a Flomax case:
    In general, for Flomax settings, particularly with light irides or marginal dilation whom will not require pupillary expansion, I try to prevent the AC from bouncing as I want as little disturbance to the iris as possible. Thus, I use a slightly lower bottle height to start with and continuous irrigation. Also, very important to reverse pupillary block by creating space between the iris and the anterior lens capsule with an instrument before irrigating into the eye. Regarding settings, I will decrease aspiration a little as necessary, but decreasing too much will also increase surgical time, which in turn leads to greater time in the eye and potential iris problems. (Elizabeth Yeu)

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    47. What settings and techniques do yo use for a vitrectomy with the Alcon Infiniti using both the 19 and 23 gauge vitrectors with the Pars Plana and Corneal approach, and what do you use for the split irrigation?

    Vitrectomy with the Alcon Infinity using both the 19 and 23 gauge vitrectors with the Pars Plana and Corneal approach, & split irrigation
    For anterior vitrectomy, always important to use Cut- I/A setting in order to minimize the traction of the vitreous. For Infiniti, I use an 800 cut rate, vacuum 200, and aspiration 15, with a bottle height of ~55. I use the 19 g Alcon instruments and use two paracenteses in order to create a tight seal and prevent egress of fluid (and potential vitreous). Bimanual ant vitrectomy is much more controlled than co-axial ant vitrectomy, and it is the same instrument that is just split instead of connecting through same sleeve.

    For pars plana approach and the Alcon Inifiniti, I use the same 19 g instruments provided, and go back 3 to 3.5 mm from limbus. Depending how much vitrectomy is needed, I gauge the amount of irrigation is put into the anterior chamber through the paracentesis as I do not want to direct more vitreous to come forward. Short vitrectomies, i.e. pars plana capsulotomies in pediatric cataracts, do not require irrigation into the AC. (Elizabeth Yeu)

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