2013 Co-Management Management of complications Dr. Malik

Management of SBK Intralase ComplicationsAngela Malik ODFocus Eye Center

Management of SBK Intralase Complications 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

Diffuse Lamellar Keratitis (DLK) 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

DLK

DLK Appearance Treatment Follow up

Grade 1 Sectoral, Less

than 30%PF q 2 hrs 2 days

Grade 2 Affects VA, Cells cross pupillary

axis

PF q 1 hr 24 hrs

Grade 3/4 Dense haze, reduced VA, Fb

sensation, photophobia

PF q 1hr pulse or flap to be lifted and

irrigated

Immediate

1 2

3 4

Epithelial Ingrowth 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

Epithelial Ingrowth 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

Transient Light Syndrome (TLS) 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

Dry Eye 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

Dry Eye Preoperative dry eye symptoms, environmental

factors, computer use, ocular surface disease, menopause, autoimmune disease, medications

Symptoms include foreign body sensation, burning and reduced acuity at end of day

Treatments vary depending on severity: artificial tears, punctual plugs, cyclosporine, lipiflow

Striae 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

Striae 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

Subconjunctival Hemorrhage 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

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

Ectasia 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 cross-linking

Epithelial Defect 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

Interface Debris 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

Central Toxic Keratopathy (CTK) CTK is a rare, acute, non-

inflammatory 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

Central Toxic Keratopathy (CTK) Findings resolve within 2-

18 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

Conclusion Flaps created with the femtosecond laser are

thinner, smaller and more precise

iFS lasers increase safety, decrease risk of ectasia, dry eyes and epithelial ingrowth

As with all surgical procedures, problems can occur. Never has the technology been so advanced allowing complications rates to be minimal