1. Dr. Rohit Agrawal presented on the history and techniques of phacoemulsification. 2. Key developments included Charles Kelman's early work in the 1960s and the introduction of foldable IOLs and topical anesthesia in the 1980s. 3. Phacoemulsification uses ultrasound energy and a fluidics system to emulsify and remove the crystalline lens through a small incision. Common techniques discussed were divide and conquer, stop and chop, and vertical and horizontal chopping approaches.

1. PHACOEMULSIFICATION
MODERATOR- DR. S. BANAIT SIR
CONDUCTOR- DR. PRADNYA MADAM
PRESENTER- DR. ROHIT AGRAWAL
29/10/2018

2. • In 1966 Charles Kelman made a Peristaltic Pump
and conducted phacoemulsification research on
animals.
• In 1967 he performed 1st phacoemulsification in
human. It took 4 hours and 3 litres of fluid.
• 1986 Mazzoco (US), Barrett (AUS): Foldable IOL
• 1986 Kimiya Shimizu (JAP): Topical Anaesthesia
• 1987 Gimbel: invented CCC and Hydrodissection
• 1995 Howard Fine (US): temporal clear corneal
incision
HISTORY
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3. • Phacoemulsification surgery comprises of 2 basic elements-
• Ultra sound energy
• Fluidics system
• Ultrasound energy is used to emulsify the crystalline lens so that 10 mm lens can be removed
from a incision 3mm or less.
• Fluidics system is employed to counteract the potential heat build-up and repulsive action of
ultrasonic needle, as well as to remove the emulsate via the aspiration port while maintaining the
adequate depth and pressure in anterior chamber.
MACHINEOVERVIEW
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4. • This circuit is supplied via the silicon sleeve’s irrigation port by an elevated irrigating
bottle that supplies both fluid volume and pressure to maintain anterior chamber.
• Pressure of anterior chamber is directly proportional to height of the bottle.
• The fluidics system is driven and regulated by a pump that not only clears the chamber of
emulsate, but also provides other clinical utility.
• When the aspiration port is unoccluded, the pump provides currents in anterior
chamber which attracts nuclear fragment. (measured in cc/min)
• When aspiration port is occluded, the pump provides holding power (vacuum in mm Hg)
which grips the fragment and allows further manipulations.
• In order to fully exploit the potential of phaco machine, the surgeon must understand the
logic behind setting the parameters of bottle height, ultrasound power vacuum and flow
rate.
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5. PATHWAYOFFLUIDFLOW
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6. • Ultrasonic power is most often produced by enclosed
piezoelectric crystals which convert electricity into
mechanical vibration.
• This energy is transmitted along the handpiece into
phaco-needle in such a way that primary oscillation is
axial.
• Irrigating fluid flows through two ports located 180° apart
on the silicon sleeve surrounding the phaco tip.
• Fluid flows between needle and silicon sleeve.
• Normal frequency of various phaco machines ranges from
20,000 to 80,000 (20-80 KHz) Hertz. Frequency is fixed for
particular machine. Usually it is in the range of 40 KHz.
• Stroke length is the forward and backward movement of
the needle along the longitudinal axis.
• These oscillations are between 70-120 microns wide.
Ultrasonichandpiece
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7. • These are made up to titanium.
• It can have an opening angulation of 0°, 15°, 30°, and 45°.
• Greater angulation facilitates sculpting whereas lower angle is good for occlusion.
• 30° tip is suitable for both functions and is the most preferred one.
• The tip is covered with silicon sleeve that insulates and protects the tissue at the incision site.
PHACOTIPS
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8. 1. STANDARD TIP-
• It has a straight shaft of 19 gauge and requires 2.8-3.2mm incision.
• This is the tip of choice for traditional divide and conquer surgery.
TYPESOFPHACOTIP
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ANGLE CUTTING POWER HOLDING POWER KEY POINT
0° * ***** Phaco chop
15° ** ****
30° *** *** Beginners
45° **** ** Sculpting
60° ***** * Rarely used now

9. • 19 gauge needle
• Advantage of increased cutting ability.
• Higher stroke length
• Higher incidence of wound burn
• Disadvantage is it has 180 degree cutting edge that cut through the periphery of the lens.
2.KELMANTIP
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10. • 19 Gauge needle.
• Has grooves in outer shaft.
• Has the advantage that grooves in the outer shaft helps cool down the tip.
3.BARRET’SMICROFLOWTIP
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11. • 19 gauge needle
• Has increased size at the end of the needle shaft.
• Used for magneto-restrictive hand pieces that have tendency to heat up faster as compared to
piezoelectric hand pieces.
• Rarely used now.
4.COBRATIP
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12. • Straight shaft
• 21 gauge tip
• Have thicker sleeve.
• Enhances surge protection because of smaller internal diameter.
5.MICROSEALTIP
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13. • Thin polyamide insulation tubing separates metallic shaft of the tip from the insulation sleeve.
• Reduces heat transmission.
6.MACKOOLTIP
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14. • It has a 0.18mm diameter hole at distal end.
• Provides continuous outflow throughout nucleus emulsification even during occlusion.
• It had advantage that it cools down phaco needle, incision site and entire anterior chamber by replacing
the fluid continuously.
• Less chances of surge.
7.ASPIRATIONBYPASSSYSTEM[ABS]TIP
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15. 1. CO-AXIAL IA HANDPIECE
• Smooth rounded tip, 2 ports for irrigation and 1 for aspiration.
• Irrigation ports are placed 90 degree away from aspiration port.
• Size of aspiration port is 0.2mm-0.7mm.
• Smaller port maintains better vacuum seal but takes longer time for aspiration.
IAHANDPIECE
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16. • ASPIRATION HANDPIECE
• Usually curved, rounded tip
• Port is 1 mm from the tip
• IRRIGATION PORT
• Straight or curved
• Port at the tip
2.BIMANUALIAHANDPIECE
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17. • Phaco machines come with a foot switch to control functions
of the machine.
• Newer machines can almost be totally controlled with the foot
switch.
FOOTSWITCH
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18. • FLUIDICS
• PHACO POWER
• SURGE
PHACODYNAMICS
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19. • It has 2 components-
1. Irrigation system
2. Aspiration system
FLUIDICS
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20. • Flow rate:
• The quantity of liquid (measured in cubic centimeters = CC) which circulates in unit time (one minute) is defined as
flow.
• The liquid flows downwards under gravity from the infusion bottle, passes through infusion line and reaches the eye
through handpiece.
• The flow of fluid is mainly responsible for bringing the nucleus fragments towards the phaco tip
• CONVENTIONAL PHACO
• 80-85 cc fluid/Min
• With every 15 cm (6”) increase in bottle height above the eye, IOP increases by 11 mm Hg
• Ideal bottle height is 3±1 ft (1ft=12”)
• MICRO PHACO
• Aspiration occurs through phaco tip and irrigation through an irrigation chopper.
• 40-45 cc fluid/min
• This is not enough to maintain anterior chamber so irrigation is increased via irrigating chopper
IRRIGATIONSYSTEM
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21. • Increase bottle height
• Atmospheric pressure pump
• AC maintainer
• Pressurise bottle by injecting air
• Mechanised pressure infusion
• Pressurise plastic bottle by BP cuff
Methodstoincreaseirrigationthroughirrigatingport
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22. • FUNCTIONS-
• Anterior chamber lavage
• Creation of hold for emulsification of nucleus
• ASPIRATION FLOW RATE [AFR]-
• Volume of fluid in ml/min removed from eye.
• Determined by pump speed, compliance, venting and tubing.
• High AFR- swifter removal of lens matter with less power
• Low AFR- used when working near capsule
ASPIRATIONSYSTEM
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23. • Ability of fluidic system to attract and hold nuclear or cortical matter on the distal end of hand piece until the material
is evacuated by vacuum forces.
• It is created due to pressure gradient of the tip [positive pressure form infusion and negative through vacuum]
• Venturi pump is more efficient than peristaltic pump in creating negative pressure, so followability is good.
• ZONES OF FOLLOWABILITY
A. ZONE OF GOOD FOLLOWABILTY- area around phaco tip
B. ZONE OF POOR FOLLOWABILITY- near angle of AC and fornices
C. ZONE OF NO FOLLOWABILITY- area around main port and side port and near dome of cornea.
Followability
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24. • FLOW PUMPS
• AFR and vacuum is pre-set by the surgeon.
• AFR is maintained while vacuum varies with fluidics resistance up to maximum set limit.
• PERISTALTIC PUMPS
• SCROLL PUMPS
• VACUUM PUMPS
• Surgeon controls the vacuum
• VENTURI PUMP
• DIAPHRAGMATIC PUMP
• ROTATORY VANE PUMP
Typesofaspirationsystem
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25. • The rotation of the rollers by the pump pinches the soft, silicon tubing, creating a negative pressure by
squeezing the fluid out of the tube.
• The faster the rollers rotate, more fluid is withdrawn and therefore there is a higher flow rate.
• In this system, vacuum will be built up only after the tip is occluded.
• Flow rate and vacuum can be set independently in a peristaltic system.
PeristalticSystem
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26. • The swift movement of a compressed gas creates vacuum, inside a closed chamber which is then directly
transmitted to the handpiece.
• The amount and speed of the gas decides the level of vacuum developed in the cassette.
• When the surgeon depresses the foot pedal, the preset vacuum level is immediately created.
• In the venturi system only the level of vacuum can be controlled and not the flow rate.
• Here the flow rate is a fixed.
• The advantage of the venturi pump is that it is able to create the pre-set vacuum level without occlusion
of the phaco needle tip
VenturiSystem
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27. PERISTALTIC PUMP VENTURI PUMP
Flow based Vacuum based
Vacuum created only when phaco tip is
occluded by cataract material
Vacuum is created instantly by the pump
once surgeon presses the foot pedal
Flow is constant until the occlusion Flow varies with vacuum level
Drains into soft bag Drains into rigid cassette.
Less followability More followability
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28. • MECHANISM OF ACTION
• DIRECT IMPACT [jackhammer effect]- depends upon stroke length and frequency of vibration.
• CHATTER- repulsion of nuclear fragment from the tip
• CAVITATION- formation of gas bubble from the fluid in response to pressure changes at phaco tip.
Implosion of these bubbles produce brief instances of intense heat and pressure.
• ACOUSTIC WAVE EFFECT- sonic wave propagation through the fluid.
PHACOPOWER
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29. • Continuous mode
• Pulse mode
• Burst mode
• Hyperpulse mode
Modesofphacopowerdelivery
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30. • All the time ultrasound is ON at gradual manner (LINEAR) depending upon foot pedal
position 3 …….no OFF
• In Every second……. all second is full with ultrasound
Continuousmode
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31. • In pulse mode each pulse of energy is followed by a gap of equal duration.
• For effective power delivery, the nuclear fragment has to be held, so the interval between the pulses of
phaco allow the vacuum to build up and thus a good hold is developed.
• Pulse mode is a variant of linear phaco mode where the frequency of the pulses is fixed and the phaco
energy delivered in each pulse will depend on the amount the pedal is pressed.
• Thus the power is delivered at pre-set intervals, the frequency of which is pre-set and decided by the
surgeon.
• Phaco is not on throughout all part of 1 second.
• With in 1 second …in part of second phaco is ON and in another part of second phaco is OFF….there is
pause in ultrasound
• Eg..1 If we have 2 pulses/sec…
• Means in 1 sec 2 on cycle and 2 off cycle ( i.e total 4 cycle)
• So each pulse is of 250 millisec..( 1sec= 1000 millisec)
Pulsemode
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32. • Advantages-
• Phaco power delivery is reduced by 50%
• Stable anterior chamber
• Decreased chatter at the tip
• Allows more followability
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33. • In Burst mode energy is fixed and the frequency of phaco bursts will increase with increasing depression of
the foot pedal in phaco mode.
• Maximum preset power is delivered with each burst, but interval between the burst decreases as the foot
pedal is depressed.
• At the end of position 3 excursion, the power delivery becomes continuous.
• ADVANTAGES-
• Uses less US energy than pulse mode
• Helpful in hard cataracts
Burstmode
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34. • Hyperpulse allows the surgeon to choose from new, higher-range pulse settings that can exceed 100 pulses
per second (compared with traditional pulse, which had a maximum of 20 pulses per second).
• Linear power delivery with “off time more than on time”.
• Advantages-
• Low energy delivered due to brief duration pulses.
• Thermal protection against corneal burns.
• a/k/a COLD PHACO.
• Increased followability
• Decreased chatter.
Hyperpulsemode
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35. • Sudden withdrawal of fluid from AC after occlusion break is called surge.
• Effects of surge-
• Anterior chamber collapse
• Damage to iris and cornea
• Posterior capsular rupture
• Factors contributing to surge-
• Compliance of tube
• High vacuum level
• High AFR
SURGE
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36. 1. Venting-
• In this, the machine has a sensor which detects occlusion break and releases fluid/air into the system to fill the volume of the re-
expanding tubing. This prevents fluid being drawn out of the AC.
2. Delay in start of the motor following occlusion break-
• Here, following occlusion break, start of the motor is delayed till the expansion of the tubings is complete
3. Decreasing the effective flow rate
4. Increasing the infusion
5. The use of an Anterior chamber maintainer
6. Proper wound construction
7. Increased viscosity of the AC contents
8. ABS tip
Controlofsurge
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37. • Change of the tubing shape and volume when put under negative pressure.
• When the tip of the phaco needle is occluded, negative pressure will build in the tubing.
• The higher the compliance the more change in the tube’s volume. When negative pressure is created
highly compliant tubing collapses on itself reducing its inner volume’s capacity.
• When occlusion breaks, the tubing returns to its original shape and a temporary imbalance exists causing
rapid exit of fluid from the anterior chamber. This is called Surge.
• The higher the compliance the greater the surge amplitude during occlusion break
Compliance
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38. • Vacuum is generated by the machine and is a measure of the strength of the ‘hold’ that the handpiece has
on the nucleus.
• Level of vacuum and port size will determine how strong the grip is.
• The holding power is inversely proportional to the port size.
Vacuum
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39. PHACOEMULSIFICATION
TECHNIQUES
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40. • The term divide and conquer was First used to describe a technique for removal of the cataractous lens
nucleus using phacoemulsification by Gimbel in 1986.
• This technique involves dividing the hard lens nucleus in half and then typically into quarters, enables the
safe and efficient disassembly and removal of the cataract while preparing for lens implant insertion.
Divide-and-ConquerTechnique
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41. • The stop-and-chop phacoemulsification technique entails several simple steps and is a very efficient method for
emulsifying the nucleus of any density.
• Sculpting is performed to prepare space in the middle of the cataract , where the nucleus can be manipulated later on
in the procedure.
• The sculpting should produce a trench in soft and medium-density cataracts and a large crater in dense cataracts.
• The posterior plate is split , producing two nucleus halves that are free- floating.
• At this point, nucleus preparation stops and the emphasis shifts to the chop.
• The nucleus is rotated 90 degrees and the phaco tip is buried deeply into the hemi-nucleus about one third of the way
from right to left.
• The chopper is placed in the periphery of the nucleus and pulled toward the phaco tip.
• As the instruments reach each other, they are separated, chopping of the nucleus segment.
Stop-and-ChopPhacoemulsification
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42. • It is of types-
• Vertical chop
• Horizontal chop
Phaco-ChopProcedure
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43. Horizontalchop
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The handle of the chopping
instrument is rotated to the
right until horizontal, resulting
in rotation of the tip so that it is
parallel to the nucleus and can
be easily passed under the
anterior capsule.
Once past the junction of the
epinucleus/cortex junction with
the endonucleus, the handle is
rotated back to vertical, which
allows the tip to pass around
the nucleus equator in
preparation for the horizontal
chop.
First horizontal chop. The
chopper passes beneath the
anterior capsule edge to hook
the nucleus equator. The phaco
tip impales the nucleus
proximally. The phaco tip will
move right ward with a slight
lifting motion.

44. Verticalchop
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Vertical chopping. The phaco tip is placed
into the middle of the nucleus, impaling it.
The sharp chopper is placed adjacent to the
tip and driven into the nucleus. Once both
instruments are stable, the phaco tip is
pushed and lifted up and rightward and the
chopper is pulled down and pressed
inferiorly.

45. THANKYOU
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46. • CASE
• PRESENTER- DR. ARJAN
• MODERATOR- DR. SUNE SIR
• CONDUCTOR- DR. NAGPURE MADAM
NEXTPGACTIVITYON30/10/18
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