Phaco surgery , phacoemulsification cataract surgery , Tilganga Institute of Ophthalmology , TIO,

1. PRAKASH BAM
RESIDENT (2ND YEAR)
TIO, NAMS
PHACOEMULSIFICATION

2. CONTENTS
Definition
History
Phaco-instrumentation and phacodynamics
Basic surgical steps of phacoemulsification
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3. Definition
Greek; “phaco” lentil or lens “emulsification” fine dispersion of minute droplets
of one liquid in another in which it is not soluble or miscible
Phacoemulsification is a form of extra-capsular cataract extraction (ECCE) in
which ultrasonically driven tip is used for fragmentation and aspiration of lens
nucleus through a very small surgical wound.

4. HISTORY
Charles D. Kelman in 1967 developed phacoemulsification
surgery.
A TRIP TO THE DENTIST
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Charles D. Kelman

5. PHACO-INSTRUMENTATION

6. COMPONENTS
CONSOLE HAND-PIECE FOOTPEDAL
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7. CONSOLE AND INTERNAL PUMPS
It is the computer which controls
all the functions of the machine
Aspiration flow rate ( AFR)
Vacuum
Phaco power
Phaco mode ( continuous, pulsed,
burst; panel, surgeon/linear)
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8. Hand Piece
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10. Phaco-needle tip
Tip of the hand-piece
Hollow titanium needle
Approximately;
Inner diameter: 0.9mm
Outer diameter:1.1mm
Transmits vibration at
high(ultrasonic) speed (27,000-
60,000 cycles per second)
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11. Phaco needle tip design
Straight
Lesser area of impact
Angled tip
Increases the area of impact
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12. Phaco needle-tip designs
Bevel angle
0˚, 15 ˚, 30 ˚, 45 ˚, 60 ˚ and combined
30 ˚/60 ˚ turbo beveled tip
Tips with steeper bevels are better for
cutting nuclear material
Tips with greater bevel have greater
surface area hence have greater
holding force
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13. Foot Pedal
Foot pedal
Irrigation
Aspiration
Phacopower
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14. PHACODYNAMICS

15. Principle
To balance fluidics within the eye, while
delivering ultrasonic energy & vacuum –
to emulsify & aspirate the cataract
through a small incisions.
Ultrasonics
vacuum
Fluid-
dynamics
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PHACODYNAMICS

16. Ultrasonic frequency is by definition greater than 20 000 Hz.
Electromagnetic energy is generated in the machine body and travels by means of
connecting cables to the phaco handpiece where a transducer converts this energy into
ultrasonic vibration of very high frequency (28,000 to 60,000 Hz)
This is then transmitted to the ultrasound tip as a longitudinal oscillation of mechanical
energy.
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Ultrasonics

17. Stroke length
It is the linear distance the tip traverses
to produce an impact on lens material.
It varies among various devices from 2-
4mils( 0.05-0.10mm or 0.002”-0.004”)
It is the stroke length of the phaco tip
that is changed when the power is
changed
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18. Phaco Power
The ability of the phaco needle to vibrate and cavitate the adjacent lens
material.
Power is noted as a linear percentage of the maximum stroke length of which
the needle is capable.
Phaco power is produced when the foot pedal is depressed to position 3
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19. Measuring Energy in Phacoemulsification
Energy in phacoemusification is measured as
Absolute(Effective) Phaco Time (AFT/EPT)
Total phaco energy delivered
APT = Phaco time * Avg power
Eg 10 secs at 100% power = 10 secs APT
Eg 20 secs at 50% power = 10 sec APT

20. ‘On’ time and ‘Off’ Time
On time – time duration for which ultrasound energy is
working or is switched on
Off time – time duration for which ultrasound energy is
switched off

21. Duty Cycle
Duty Cycle = on time / (on time +off time) multiplied by 100
Duty cycle = 5/5+5 *100

22. Continuous mode
Pulse mode
Burst mode
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Modes of Phaco-Power Delivery

23. Continuous mode
There is a constant delivery of phaco power
when the machine is in foot-pedal 3.
Panel control: the set level of power(0-100%) is
delivered when the food pedal is depressed
throughtout the position 3.
Linear/ Surgeon control: the surgeon controls the
amount of phaco power delivery by varying the
excurtion of foot pedal while it is in position 3
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24. Pulse mode
Pulse is an interval of phaco
power turned on alternating
with the same interval during
which phaco power is off..
Duty cycle : 50%
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25. Burst mode
Involves delivery of preset power (0-
100) in single bursts that are separated
by decreasing intervals as the foot pedal
is depressed through position 3.
At the end of the position 3 excursion,
the power is no longer delivered in
bursts but is continuous.
Burst mode allows the phaco needle tip
to bury into the lens, an essential step
for chopping techniques.
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26. The disruption of the lens nucleus
occurs by 2 processes
Cavitation
Jackhammer effect
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27. Cavitation
As the tip moves forward, compression of gas atoms
in solution occurs; as the tip moves backward,
expansion of gas atoms occurs and bubbles of gas
are formed.
When the bubbles implode, they release heat and
shock waves (cavitation) that contributes to actively
disassemble the nucleus.
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28. Jack hammer effect
To and fro movement of the
phaco-tip cause the fragmentation
of the nucleus.
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29. Aspiration Flow Rate
The amount of fluid that is aspirated
out from the eye .
Measured in cc/min
Followability/ Attractability

30. Vacuum
Negative pressure in the tubing
Measured in mm of hg
Holdability

31. The aspiration of fluid or the fragmented lens is facilitated by the vacuum
generated by pump system.
Peristaltic pump
Venturi pump
Diaphragm pump
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32. Peristaltic Pump
It consists of a set of rollers that move along
flexible tubing, forcing fluid through the tubing
and creating a relative vacuum at the aspiration
port of the phaco tip.
Vacuum response time with this type of pump
is relatively rapid;
Linear control is achieved as the speed of the
rollers is increased.
Vaccum is flow based and does not build up
until the tip is occluded
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33. Venturi Pump
The Venturi pump creates a vacuum based on
the Venturi principle:
A flow of gas or fluid across a port creates a
vacuum proportional to the rate of flow of
the gas.
This system produces a rapid, linear rise in
vacuum and allows for instantaneous venting
to the atmosphere that immediately stops the
flow through the port.
The vacuum is not flow based and builds
according to the machine setting.
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34. Venturi Pump
Vacuum based
No occlusion is required for creation of
vacuum
Fast and efficient
Instant vacuum
Drains into rigid cassette
Peristaltic Pump
Flow based
Occlusion is required for generation of
vacuum
Less efficient
Slow development of vacuum
Drains into soft bag
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35. Diaphragm Pump
The diaphragm pump consists of a flexible
diaphragm overlying a fluid chamber with
one way valves at the inlet and outlet.
This type of pump system produces a slower
rise in vacuum. With continued occlusion of
the aspiration port, however, the vacuum will
continue to increase in an exponential
manner.
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36. Followability
The ability of a fluidic system to attract and hold nuclear or cortical material on
the distal end of an ultrasonic or irrigation/aspiration hand-piece until vacuum
forces achieve evacuation .
Followability  occlusion  vacuum
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37. Chatter
When the ultrasonic stroke overcomes the vacuum or holding power, the
nuclear fragments are repelled by the ultrasonic tip.
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38. Surge
A phenomenon that occurs when vacuum has built up because of an occlusion and the occlusion
is suddenly broken, leading to the fluid in the higher-pressure (positive) anterior chamber
tending to rush into the lower-pressure (negative) phaco tip.
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39. How to avoid surge?
Increase the bottle height
Decrease the vacuum
Decrease aspiration flow rate
Low compliance tubing of smaller diameter
Occlusion mode software
Venting
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40. The process whereby negative pressure of vacuum is equalized to
atmospheric levels to minimize surge
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Venting

41. A Basic Outline of Phaco Procedure

42. Steps
Exposure of the globe
Paracentesis
Clear corneal incision
Continuous curvilinear capsulorrhexis
hydrodissection
hydrodelineation
Phaco technique
IOL insertion
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43. Paracentesis
Approx. 2-3 clock hours away from the site
where an incision will be made for phaco
hand-piece
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44. Clear corneal incision
Commonly performed incision in phaco
3.2mm or less
Just large enough to accommodate the phaco
hand-piece.
Usually have no or little effect in pre-existing
astigmatism.
The incision can be made superiorly ,
temporally or the steepest axis of the cornea.
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45. Approaches for clear corneal incision
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46. Trypan blue

47. The Cystitome

48. Continuous Curvilinear Capsulorrhexis
It allows utilization of the elastic
properties of the capsule to express the
nucleus from the capsular bag and place
an IOL in the bag without causing radial
tear
Allows safer manipulation within the bag
Prevents Iris from rubbing the IOL surface
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Prof Dr Govinda Poudyal’s
Phacoemuslification Surgery Video

49. Hydrodissection
It is performed to separate the
peripheral cortex from the underlying
capsule
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50. Hydrodelineation
Injecting BSS into the substance of
the nucleus to separate epinucleus
from the endonucleus .
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51. Techniques of nucleus disassembly
Numerous ways to remove the endonuclei have been described.
Sculpting
Fracturing
Emulsifying
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52. Sculpting
Process of debulking the central nucleus and
involves shaving maneuver
The tip of the phaco needle is never fully
occluded, only incidental vacuum is
generated
Modest vaccum, low aspiration flow and
high power

53. Fracturing

54. Stop and chop

55. Divide and conquer
John Shepard,MD ( divide and conquer)
a deep central linear groove or trough is sculpted in the
nucleus, with continuous ultrasound used for sculpting.
the deeply grooved nucleus is rotated to create troughs to
divide each half into quadrants.
The phaco tip and second instrument are inserted into
each groove and spread apart, thereby achieving the
complete separation of the pieces
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56. Phaco- chop
Phaco- chop is done bimanually with phaco
tip and second instrument
Chopping is done by burying the phaco tip
into the nucleus and using chopper which
deeply engages the endonucleus in the
periphery and drawing it towards the
phacotip

57. Grasping and emulsification
Vaccum grasps nuclear fragment,
brought to safe zone and
emulsified
Low flow, high vaccum and high
power

58. Location of emulsification
Anterior chamber
Iris plane
Posterior chamber (in the bag)
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59. Anterior chamber
Advantages
•Excellent visibility
•Reduced risk of PCR
Disadvantages
Corneal endothelial trauma
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60. Iris plane
Advantages
Reduced risk of damage to
endothelium and posterior
capsule
Safer in patients with small pupil
and loose zonules
desirable for beginning phaco
surgeons
Disadvantages
Difficulty in prolapsing the nucleus
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61. Posterior chamber (in the bag)
Advantages
Reduced risk of corneal endothelial
trauma
Better control of the nuclear pieces as
they are contained within the bag
Disadvantages
Greater stress placed on the posterior
capsule and zonular fibers when the
nucleus is being manipulated,
Technical difficulty in small-pupil cases
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62. Cortical aspiration
Coaxial Irrigation aspiration with phaco-
needle without ultrasound
Bimanual irrigation aspiration canula
Manual Irrigation/aspiration (simcoe)
cannula
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63. Intra-ocular lens insertion
Foldable lenses are preferred for
small incision phacoemulsification.
The foldable IOL is inserted with
injector.

64. Wash OVD thoroughly
Ensure AC is well formed
Hydrate corneal incisions
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65. References
Albert and Jacobiec Principles and Practice of Ophthalmology, 2nd edition, volume 2
Myron Yanoff and J.S. Duker Ophthalmology, third edition
Basic and Clinical Science Course, Lens and Cataract, American Academy of
Ophthalmology(2020- 2021)
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