2013 Co-Management Management of complications Dr. Malik

1. Management
of SBK Intralase
Complications
Angela Malik OD
Focus Eye Center

2. Management of SBK Intralase
Complications
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85% of surgery is SBK
Most common post-op complications manifest in
the first few months
Complications can be divided into 3 categories:
Flap
Interface
Biomechanical

3. Diffuse Lamellar Keratitis (DLK)
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Most common post operative
complication
Sterile inflammatory reaction
which develops within 48 hours
Diffuse white granular infiltrates
Graded from 1-4
Treat with an intense course of
topical steroids
Multiple causes: laser
energy, repeated
suction, interface
debris, bacterial endotoxins

4. DLK
1
3
DLK
Grade 1
Grade 2
Grade 3/4
Appearance
Sectoral, Less than
30%
2
4
Treatment
Follow up
PF q 2 hrs
2 days
Affects VA, Cells
cross pupillary axis
PF q 1 hr
24 hrs
Dense haze,
reduced VA, Fb
sensation,
photophobia
PF q 1hr pulse or flap
to be lifted and
irrigated
Immediate

5. Epithelial Ingrowth
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Presence of corneal epithelium in
the interface
Incidence lower in primary
treatments and higher in
retreatments
Etiology is poor flap adhesion
Clear or white nests appearing
within 3-6 months
Superior hinged flaps, EI presents
at the inferior margin and the
hinge

6. Epithelial Ingrowth
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Severe cases will cause
decreases acuity, foreign
body sensation, glare
and astigmatism
Necrotic epithelial cells
will release collagenase
and protease which will
cause the cornea to melt
Treatment:
Mild/non progressing;
accurately measure and
monitor
Moderate/ progressing;
flap lifted and scraped
and 20% ethanol alcohol
applied

7. Transient Light Syndrome (TLS)
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Incidence is less than 0.1%
Unique to the femtosecond laser
Severe photophobia 2-6 weeks
Good UCVA and no inflammatory slit lamp
findings
Laser energy can stimulate local keratocytes or
corneal nerve endings
Treat with PF q2hrs x 48 hrs then qid x 2 wks

8. Dry Eye
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Caused by an inadequate
quantity or quality of the tears
Neurogenic theory: surgical
destruction of the nerve endings
from the sub epithelial plexus
SBK destroys less nerves by
creating a thinner flap and
cutting at a steeper angle
Cornea fails to sense the need for
lubrication, inadequate lacrimal
secretions and decreased blink
rate
Most dry eyes resolve within 3
months

9. Dry Eye
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Preoperative dry eye symptoms, environmental
factors, computer use, ocular surface disease,
menopause, autoimmune disease, medications
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Symptoms include foreign body sensation, burning
and reduced acuity at end of day
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Treatments vary depending on severity: artificial
tears, punctual plugs, cyclosporine, lipiflow

10. Striae
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Folds in the corneal flap.
Can be micro or
macro, central or peripheral
Microstraie:
Microscopic, superficial
wrinkles. Px asymptomatic
Macrostraie: full thickness
folds that cause visual
impairment and discomfort.
Requires surgical
intervention
Best evaluated with
retroillumination

11. Striae
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Early treatment is
associated with better
visual outcomes and
reduced risk of developing
fixed folds
Treatment involves lift and
hydrate the
flap(refloat), stretch and
smooth
Longstanding striae
requires debriding the
epithelium overlying the
striae
Prevention is key

12. Subconjunctival Hemorrhage
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Defined as bleeding under the
conjunctiva
The small limbal capillaries are
fragile and easily damaged
from suction
Variables include resilience of
the blood vessels, certain
medication and patients
anatomy
Patient should be informed or
will be concerned
Complete resolution may take
2-4 weeks
More common in LASIK
because of a high vacuum
suction
Purely a cosmetic side effect.
No visual or clinical significance

13. Ectasia
 History
of progressive
myopia and
astigmatism post-op
 Incidence is 0.1%
 Decrease risk by
preserving enough
residual tissue in the
stromal bed, average is
250 microns, FEC is 320

14. Ectasia
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Pre-op red flags include
questionable topographies
in young patients who need
large corrections
Post-op topographical
findings consistent with
ectasia should be referred
back for a Pentacam and
possible collagen crosslinking

15. Epithelial Defect
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Occurs at the time of
surgery
Can be classified as central
or peripheral, large or small
and traumatic or toxic
Usually small( less than
3mm)
Possible causes include
speculum, ink
marker, excessive use of
topical anesthetics and
EBMD
Bandage CL's are left on
more than 24hours if the
defect is large or patient is
symptomatic

16. Interface Debris
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Can be defined as
mucous, dust, cellular
debris, powder from surgical
gloves
, lint, fibers, hemoglobin or
hair that is trapped in the
interface
If DLK occurs manage with
steroids
If it affects vision removal is
indicated
Remove large strands of lint
that extend beyond the
edge with forceps
If detected just post-op it can
be removed at the slit lamp

17. Central Toxic Keratopathy
(CTK)
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CTK is a rare, acute, noninflammatory process that
causes a central corneal
oppacification and a
hyperopic shift
Often misdiagnosed as
grade 4 DLK
Opacification occurs 3-9
days after surgery
Striae are characteristic of
CTK but are not always
present

18. Central Toxic Keratopathy
(CTK)
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Findings resolve within 218 months post op
Unknown cause but it
appears that something
toxic to the cornea is
activated by the laser
Referred back to FEC
urgently
Corticosteroids are used
in treatment as it may
be difficult to
differentially diagnose it
from DLK

19. Conclusion
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Flaps created with the femtosecond laser are
thinner, smaller and more precise
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iFS lasers increase safety, decrease risk of
ectasia, dry eyes and epithelial ingrowth
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As with all surgical procedures, problems can
occur. Never has the technology been so
advanced allowing complications rates to be
minimal