Types of Refractive Surgery. Infection and Inflammation in the Refractive Surgery Patient. Inflammation vs Infection. Types of Infection

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Infection and Inflammation in the

Refractive Surgery Patient

Kurt Buzard MD FACS

Assistant Clinical Professor University of Nevada Medical School

Tulane University Medical School The Buzard Eye Institute

Las Vegas Nevada

Types of Refractive Surgery

• Incisional – Relaxing Incisions • Lamellar – LASIK – PRK • Lens Based – Lens Exchange – Intraocular Contact Lens

Inflammation vs Infection

• It is often difficult to differentiate between infection and inflammation

• Stromal infiltrate can occur in either condition

• Staining can occur after epithelial disruption and may or may not be a sign of infection • Peripheral location may differentiate

Types of Infection

• Central Corneal Ulcers

– Infiltrate/staining/sometimes hypopeon

• Incisional Infiltrates

– Abcess/often without staining/hypopeon

• Herpetic Infections

– Dendritic Pattern/SPK

• Endophthalmitis

– Hypopeon

Central Corneal Ulcer

• This case is typical of central ulcers which are extremely rare after LASIK

• This is a Pseudomonas ulcer with shiny surface, conjunctival injection and relatively fast growing

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Peripheral Corneal Ulcer

• Again peripheral ulcers are rare but more likely to be inflammatory rather than a real infection

• This is a Staph ulcer with raised borders, sunken center, corneal staining,

conjunctival injection and relatively indolent and slow growing

Methacillin Resistant Staph

after PTK

Methacillin Resistant Staph

after PTK

• This case is confusing because the periphery shows a flat paralimbal infiltrate which appears to be immune and not infectious

• But the central cornea has a diffuse gelatinous appearance with staining • Unusual appearance is the hallmark of

infection in and after refractive surgery

Incisional Infection after RK

• This case is typical of infection after incisional surgery

• Any sudden appearance of staining of incisions long after surgery should be considered a possible infection and treated aggressively

• Failure to treat properly may lead to a rapid decompensation of the cornea

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Incisional Infection after RK

After PK

Incisional Infection after RK

• This case shows how quickly infection can progress to corneal decompensation

• Only 3 days between foreign body sensation and this appearance of imminent corneal perforation

Herpetic Infection in RK

• This example of herpes simplex some time after RK is rare but shows the influence the incisions can have on the infection process • Previous herpetic infection is a relative

contraindication for refractive surgery unless the patient is quiet for a long time or is willing to be on chronic antiviral meds

Infection after LASIK

Hs 25619

Infection After LASIK

• S/P LASIK OU in

Mexico with epithelial ingrowth

• S/P removal x 2 • Sudden onset of

redness and pain with methacillin resistant staph OD

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Case Study

• 49 y/o w/f with retrolental fibrodysplasia and NLP OD

• Preop -10 + 3.25 x 90 20/20 5/1999 • Postop 20/20 oc

• RD after retinal hemmorhage 9/2000 • Corneal scraping during RD surgery and

removal of lens

AH

18692

After Removal of Ingrowth

AH 18692

Case Study

• On exam after RD surgery LP OD 1/01 • Removal of ingrowth 1/11/01

• Subsequent flap melt inferotemporally stabilized with therapeutic contact lens • Abrasion 4/01 with finger with rapid

development of methacillin resistant staph • Removal of flap, slight residual scar

AH

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Case Study

AH 18692

LASIK after PK

• 65 y/o w/m s/p PK OU 30 years prior by Max Fine with cataract formation OU • 2 months postop LASIK OU elsewhere

• The patient had a high degree of

astigmatism and the “surgeon” performed relaxing incisions in the bed of the graft • Results OD CF

OS -3.00 + 7.50 x 42 20/40

DP 27232

LASIK after PK

• The vision had been

excellent prior to surgery but immediately after surgery the vision was uncorrectable and soon thereafter pain developed DP

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LASIK after PK

• An infection

developed which was controlled with antibiotics and lifting flap leaving a large corneal scar • The patient is

presently on the cornea transplant list DP

27232

Infection After LASIK

• Epithelial ingrowth is a risk factor for infection

• Any abnormality of the flap can be an entry for bacteria

• Once begun, infection can be difficult to eradicate without removal or lifting of flap • LASIK surgery is real corneal surgery

particularly after PK

Common Inflammatory Problems

• Central sterile infiltrates • Marginal infiltrates • Sub-epithelial infiltrates

• Superficial Punctate Keratopathy (SPK) • Diffuse Interstitial Lamellar Keratitis

(DILK)

• Recurrent erosion syndrome

Inflammation After PRK

• Inflammatory infiltrates after PRK can resemble infection

• They are multifocal, appear suddenly and must be treated with heavy steroids to avoid scarring

• They may be induced by reactions to meds particularly nonsteroidal anti-inflamatories

Inflammation and scarring after

PRK after RK

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Scarring After PRK

• After inflammation, scarring occurs in most cases resulting in diminished vision and myopic regression

• Treatment involves non-touch transconjunctival ablation and careful removal of the scar • I usually utilize low dose pulse methotrexate

before and after the treatment to prevent reoccurance of the scar and Mitomycin 0.1% during and after surgery

Post-EKC after LASIK

• Post-EKC syndrome is an inflammatory response to the dead viral particles left from a previous viral infection, usually about 2 weeks previous

• Treatment is topical steroids with a slow taper, and prevention of the syndrome is steroids during the active phase of the EKC

SPK and Filaments

Superficial Punctate Keratopathy

• SPK is the endpoint of many allergic and inflammatory conditions of the cornea • The most common cause is medicamentosa

to topical medications

• Don’t forget Acanthomoeba as a possibility • Oral Evoxac 30 mg QD to TID

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Dry Eyes

• Preservative free tears • The “vegas” syndrome

– Dry eyes – Blepharitis – Allergies

• Increase estrogen

• Oral Evoxac 30 mg QD to TID • 0.1% pilocarpine QID

Sands of Sahara Syndrome

• First described by Dr Maddox • First attempts at treatment include

increasing steroids, lifting flap and irrigating bed

• Equivocal results..in fact softening of bed caused worsening of condition in several patients

Abnormal corneal wound

healing

• A variety of factors can affect corneal wound healing in general and healing in LASIK in particular

• Reactions to topical medications and/or autoimmune diseases are common etiologies of abnormal corneal wound healing

Rheumatoid cornea

Scleromalcia Perforans

• Autoimmune disease

resulting in melting of cornea and sclera • Steroids can worsen

condition

• Well treated with low dose methotrexate

Wound healing in PK with

Rheumatoid arthritis

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Methotrexate and SOS

• There are many clinical similarities between scleritis and SOS syndrome

• Softening of sclera and cornea

• Relationship between autoimmune and toxic etiologies

• Good response to MTX in both

Low Dose Pulse Methotrexate

• Comes in 2.5 mg pill

• Usual dose 7.5 to 12.5 mg a week

• Monitor CBC, BUN, Cr, Liver

• Give with internist or rheumatologist

Low Dose Pulse Methotrexate

• Very common and effective treatment for a wide range of autoimmune disease, particularly scleritis

• Once begun, treatment takes about 1 month to begin experiencing effects and is usually continued for 3 -6 months

Mild Diffuse Interstitial Keratitis

Moderate Diffuse Interstitial

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Moderate Diffuse Interstitial

Keratitis

Severe Diffuse Interstitial

Keratitis

SOS syndrome .. JB

• This patient had a preop refraction of

– 9.50 + 0.75 x 145 20\20 • One day postop had 20\40

vision and good topography

• Vision dropped … treated with MTX x 3m with return of vision

SOS syndrome ..1 day 20\40

Last 20\25 1 month 20\400 1 week 20\100 -3 -2.5 -2 -1.5 -1 -0.5 0 0.5 Diopters

1 Day 1 Month 3 months 1 year

MTX Treatment

JB

Small Clinical Study SOS

Syndrome

• 7 Patients • 13 eyes

– age 28-52 – avg preop -7.39D • One day uncorrected

vision is usually pretty good with later rapid

deterioration 0 1 2 3 4 20 25 30 40 50 60 70

One day Vaoc

Small Clinical Study SOS

Syndrome

• At 2-4 weeks, both uncorrected and best corrected vision drops with variable refraction and irregular corneal astigmatism • All patients here treated with MTX pulse at

10mg/week for 2 -6 months • 7 of 13 eyes were retreated without

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Uncorrected visual acuity

in SOS syndrome over

time

0 1 2 3 4 5 6 7 20 25 30 40 50 60 70 80 more

1 day 1 month final

SOS study #1

JG

SOS study #2

WS

SOS study #3

MN

SOS study #4

MD

SOS study #5

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SOS study #6

LS

Causes of toxic keratopathy ..

SOS syndrome

• Oil or material from microkeratome • Oil or material from

sebaceous glands • “Plume” debris • Medicamentosa?? • Epithelial disruption

Interface Debris

Irrigation Lashes

Interface Debris

• Interface debris comes from one of 2 sources

– Airborne and from drapes – Tearfilm

• To avoid this problem, leave flap exposed to air for as little time as possible

• Irrigate between flap and bed forcefully to remove debris

• Keep tearfilm clean with irrigation

Epithelial Disruption

Disruption after PRK

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Epithelial Disruption

• Dry whole cornea…no fluid

• Increased risk of flap lift/epithelial ingrowth • Use CTL after surgery

• Extra steroid treatment

• Muro 128 drops and ointment in the postoperative period

• Consider immediate PTK

Hansatome

• The tolerances for the

microkeratome are remarkably restrictive • Microkeratomes vary widely from unit to unit in terms of these tolerances and finish • The “critical corner” is

most important in terms of finish

Critical Corner

Inflection Journal Traction Plane

Rust and Residual Epithelium

• Improper maintenance

and/or cleaning can result in buildup in critical areas of the microkeratome with increased epithelial disruption rates • Rust is a very effective

epithelial stripper

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Original Traction Plane 100 X

Mastel Polished Traction Plane

Case Study PS

• 34 y\o w\f (doctor’s wife) with LASIK OU for myopia & astigmatism

• Manifest : Vaoc 20/100 OD 20/150 OS – -3.75 + 3.50 x 4 20/20 – -4.00 + 3.75 x 13 20/20

Case study .. PS

0 20 40 60 80 100 120 140 160

preop 1 day 1 month2 months3 months

Vaoc OD Vaoc OS VaccOD Vacc OS

Case study .. PS

OD 1 month OS

Case study .. PS

• Treated with PTK OU

• Slow improvement over additional 6 weeks • Uncorrected 20/30 OU

– -0.25 + 0.75 x 32 20/25 – -0.50 + 0.75 x 178 20/25

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Recurrent Erosion

• 37 y/o w/m s/p LASIK OU x 9 months elsewhere • Epithelial disruption at time of surgery OD • Since surgery 3 episodes of recurrent erosion with severe SOS and mild iritis MZ

30045

Recurrent Erosion

• On last visit, patient presented from ER with 24 hour history of photophobia, pain and redness

• Uncorrected vision 20/100

• Oral and topical steroids with therapeutic CTL and topical antibiotics

MZ 30045

Recurrent Erosion

• 42 y/o w/f s/p LASIK OD for near in Colorado

• Lift the flap 3 months prior to presentation • Epithelial disruption at

time of LTF • Pain, redness and

photophobia one day prior

JG 30142

Disruption with SOS

Recurrent Erosion

• No history of trauma

and prior recurrent erosions

• This erosion occurred along the lamellar flap margin

• Fairly severe SOS accompanied the abrasion JG 30142

Moderate SOS

MDF and Epithelial Ingrowth

MM

9247

“Edge Lift” from epi ingrowth

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Epithelial Nest

RK and Epithelial Ingrowth

• Previous RK can be a

source of epithelial ingrowth

• LASIK in patients with previous RK and wide scars should be considered carefully

RK and Epithelial Ingrowth

Epithelial Nest….Treatment

Epithelial Ingrowth with MDF

Antitorque Closure

Epithelial Ingrowth with MDF

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Flap Melt

• The flap is very

delicate • This patient

experienced a flap melt after lifting the flap for epithelial ingrowth

Summary

• Preventing infection in refractive surgery patients is the same as any surgical situation

– Make sure eyelids are clean and wrap them to keep secretions away at surgery

– Sterile technique in surgery – Preop muro and antibiotic drops – Avoid herpes patients

– Fortunately infections are rare but be suspicious

Summary

• Inflammatory problems can masquerade as infections and are more common and can cause serious visual disability

• Epithelial disruption is a serious complication and can lead to inflammation/infection, prevention is important

• Low dose pulse methotrexate is an effective treatment for SOS but must be started early

Summary

• The cornea with a lamellar flap is different than a normal cornea

• Do lamellar flaps ever really heal? • With a simple corneal erosion years later,

the possiblity of SOS/infection/epithelial ingrowth is real

• Retinal cases after LASIK should be considered carefully