Femtosecond lasers are being touted as the next great leap forward in cataract surgery but, as with any radical change to our practices, many questions remain: Does this technology truly improve cataract surgery? Is the refractive accuracy better? Is the safety profile significantly elevated compared to existing technologies? Are there additional complications or issues with using this laser?

1. Eastwood
Eye Surgery
Dr Gagan Khannah
Ophthalmic Surgeon
Eastwood Eye Surgery
Macquarie University Hospital
Sydney Eye Hospital
PresMed Annual Optometrist Conference
10th March 2013
Femtosecond Laser Cataract
Surgery – Magic or Myth?
A Balanced View!

2. Laser Assisted
Cataract Surgery

3. • Individual steps of laser assisted
cataract surgery (LACS)
– Anterior capsulotomy
– Nuclear fragmentation
– Corneal incisions
• Hypothetical benefits
• Discuss the current evidence base
– very early days in adoption of LACS
– further discussion of clinical impression
Agenda

4. Does LACS:
• Improve precision and reproducibility?
• Improve safety?
• Improve refractive outcomes?
Questions

5. • Are the benefits statistically significant:
– Result unlikely to occur by chance
– Does not mean result is important or
meaningful
• Are the benefits clinically or practically
significant
• Is the benefit worth the extra time, cost
and effort
Assessing evidence for new
technology

6. • High resolution anterior segment
imaging coupled to femtosecond laser
• Anterior capsulotomy
• Nuclear fragmentation
• Corneal incisions (primary, secondary
and arcuate incisions)
Capabilities of LenSx laser

7. Anterior Capsulotomy

8. • Perform capsulotomy safely and
completely, resistant to tearing
• Central, circular and reproducible
– anteroposterior effective lens position
– lateral centration
– IOL calculations
• Predictably overlap IOL edge by 0.5mm
Anterior Capsulotomy

9. Anterior Capsulotomy
• Most striking feature of day 1 appearance
• Published evidence?

10. Anterior Capsulotomy
• Nagy
– 100% of
anterior
capsulotomies
within 0.25mm
vs 10% of
manual

11. Anterior Capsulotomy
• Tackman, Fried
man
– less deviation
from intended
diameter
– increased
circularity

12. Anterior Capsulotomy
• Zoltan Nagy
– Series of studies
– Less IOL tilt and decentration
– Better IOL-anterior capsule overlap
– Decreased higher order aberrations
• Clinical significance?
– No definite improved refractive result
(sphere, cylinder or unaided visual acuity)
– Longer term studies required
– Subgroup analysis required

13. Nuclear Fragmentation

14. • Effectively disassemble the nucleus
• Safety: protection of posterior capsule
• Safety: reduction in total phaco power
and protection of corneal endothelium
Femtosecond nuclear
fragmentation

15. • No reports of femtosecond laser direct
damage to posterior capsule
• Offset from posterior capsule on imaging
appears to be effective in preventing this
Nuclear fragmentation
- safety

16. • Reducing need to go deeper with phaco tip
may reduce risk of PC rupture
• 0.31% PC rupture rate lower than reported
incidence of 0.53% - 2.7% in manual surgery
Nuclear fragmentation
- safety

17. • Decreased total phaco energy confirmed to
statistically significant level in multiple studies
• Close to 50% reduction in both total phaco
energy and phaco time
• May reduce damage to
corneal endothelium
• May reduce potential for
inflammation and
corneal burns
Nuclear fragmentation
- safety

18. • Statistically significant reduction in phaco
energy in all grades of cataract
• No studies yet to confirm reduction in
endothelial cell loss. Further long term studies
required.
• May be particularly important in patients with
Fuch’s dystrophy
• Younger patients
Endothelial protection

19. Corneal incisions

20. Ability to
customise
reproducible, m
ultiplanar
corneal wounds
shown in
multiple studies
Corneal incisions

21. • Reproducible
wounds may allow
more consistent
surgically induced
astigmatism
• No large studies
published
at this stage
Corneal incisions

22. • Endophthalmitis a rare but devastating
complication
• Well constructed clear corneal wounds may
reduce the risk of endophthalmitis
• Difficult to study: incidence 0.13%
• A lot of data would be required to prove a
benefit in reducing endophthalmitis
Corneal incisions

23. Latest Results

24. • In this section, focus on objective current
data, not on our clinical impression
• Objective data already demonstrates
that LACS is no worse than manual
phaco
– Short learning curve
– Would not have been able to say this about move
from ECCE to phaco in first 12 months
– Took until 2001 for first large scale RCT proving
cost effectiveness of phaco vs ECCE
Conclusions

25. • New technology
– experience rising very rapidly
– 30,000 cases, almost all in the last 12 months
• Data demonstrating statistically significant
benefit in a number of areas
– at this stage relatively little definite clinically
significant data
– large number of studies currently underway
– longer term studies, eg endothelial cell loss
Conclusions

26. • Positive initial impressions, not
discouraged by:
– inability to immediately have clinically significant
evidence base
– new complications
– increases in cost
• As technology and techniques mature, history
suggests:
– complications decrease
– equipment costs reduce with widespread adoption
– outcomes and efficiencies improve
– Other technologies develop
Conclusions

27. Eastwood
Eye Surgery
Laser Refractive Cataract
Surgery
Provides Image –
guided, surgeon
control to perform:
– Anterior capsulotomy
– Lens fragmentation
– Corneal incisions
4 systems currently in
development

28. Eastwood
Eye Surgery
Laser Refractive Cataract
Surgery
Possible Advantages
– Automates steps of cataract surgery
– Improved corneal incisions & astigmatism
control
– Improved capsulotomy for effective lens
positioning
– Less phaco energy and endothelial cell loss

29. Eastwood
Eye Surgery
Laser Refractive Cataract
Surgery
Disadvantages
– Topical anaesthesia
– Cost
– Limitations
Small pupil
Corneal opacity
Dense cataract
Keratoconus

30. Eastwood
Eye Surgery
Laser Refractive Cataract
Surgery
Exciting technology and future is bright
Still in its infancy and benefits unclear
Requires better safety data & research
Costs must be addressed
Secondary advances may revolutionise
cataract surgery

31. Thank You