Introduction to Introduction to Refractive Refractive SurgerySurgery

Richard L. Nepomuceno, MDRichard L. Nepomuceno, MDDiplomate, Philippine Board of OphthalmologyDiplomate, Philippine Board of Ophthalmology

Cornea, External Disease & Refractive SurgeryCornea, External Disease & Refractive Surgery

Fatima Medical Center . St. Lukes Medical Center . Capitol Medical Center East Avenue Medical Center . Manila Central University

Cardinal Santos Medical Center . Manila Doctors Hospital

22

33

Errors of Refraction or Errors of Refraction or AmetropiaAmetropia

Problems in the Problems in the focusing focusing mechanism of the mechanism of the eye eye

causes blurred causes blurred vision because vision because light or image is light or image is not focused on the not focused on the retinaretina

44

EmetropiaEmetropia

NORMAL state of the NORMAL state of the eye eye

light or image is light or image is focused on the retinafocused on the retina

resulting in clear and resulting in clear and sharp vision.sharp vision.

55

Human Eye = CameraHuman Eye = Camera

Cornea = outer lens of the cameraCornea = outer lens of the camera Pupil = aperture of the cameraPupil = aperture of the camera Lens = inner lens of the cameraLens = inner lens of the camera Retina = film of the cameraRetina = film of the camera

66

What affects focusing What affects focusing function of the eye?function of the eye?

Shape of the cornea (steep, flat, Shape of the cornea (steep, flat, oblong, irregular)oblong, irregular)

Shape and thickness of the Shape and thickness of the crystalline lenscrystalline lens

Length of the eyeballLength of the eyeball

77

Types of Errors of RefractionTypes of Errors of Refraction

Near sightedness or myopia Near sightedness or myopia ((minusminus))

Far sightedness or hyperopia or Far sightedness or hyperopia or hypermetropia ( hypermetropia ( plusplus ) )

AstigmatismAstigmatism Mixed typesMixed types Presbyopia (reading glasses)Presbyopia (reading glasses)

88

Near SightednessNear Sightedness

Far objects = blurred Far objects = blurred Near objects = clearNear objects = clear light is focused IN FRONT of the retinalight is focused IN FRONT of the retina Due to :Due to :

long eyeballlong eyeball steep corneasteep cornea thick lens thick lens combination of the abovecombination of the above

99

Near SightednessNear Sightedness

1010

Far SightednessFar Sightedness

Far objects = clearFar objects = clear Near objects = blurredNear objects = blurred light is focused BEHIND the light is focused BEHIND the

retinaretina Due to: Due to:

short eyeballshort eyeball flat corneaflat cornea thin lens thin lens or combination of aboveor combination of above

1111

Far SightednessFar Sightedness

1212

AstigmatismAstigmatism

Both far and near objects appear Both far and near objects appear blurred or have a shadow or double blurred or have a shadow or double imageimage

light is split and falls at different light is split and falls at different location from the retinalocation from the retina

due to corneal shape (football due to corneal shape (football instead of basketball)instead of basketball)

1313

AstigmatismAstigmatism

1414

PresbyopiaPresbyopia Difficulty in reading small printsDifficulty in reading small prints normal process due to agingnormal process due to aging occurs around age 40occurs around age 40 due to weakening of the crystalline due to weakening of the crystalline

lens to focus near objectslens to focus near objects people with normal vision or far people with normal vision or far

sighted will need reading glassessighted will need reading glasses near sighted people will have to near sighted people will have to

remove their distance glassesremove their distance glasses

1515

History of Vision Correction History of Vision Correction SurgerySurgery

Dr. Jose Barraquer of Colombia (1949)Dr. Jose Barraquer of Colombia (1949) Discovered that lamellar (layered) Discovered that lamellar (layered)

corneal surgery could reshape the corneal surgery could reshape the cornea to enhance focuscornea to enhance focus

Keratomileusis – a Keratomileusis – a microkeratome(blade) removes a disc of microkeratome(blade) removes a disc of the front portion of the cornea. Freezes the front portion of the cornea. Freezes and reshapes it, then puts it back.and reshapes it, then puts it back.

1616

History of Vision Correction History of Vision Correction SurgerySurgery

Dr. Casimir Swinger (1985)Dr. Casimir Swinger (1985) nonfreeze keratomileusisnonfreeze keratomileusis

Dr. Luis RuizDr. Luis Ruiz Automated Lamelar Keratoplasty (ALK)Automated Lamelar Keratoplasty (ALK)

- automated microkeratome to reshape - automated microkeratome to reshape the cornea directly on the eyethe cornea directly on the eye

1818

Arrival of the Excimer LaserArrival of the Excimer Laser

First used in human eyes in the late 80’sFirst used in human eyes in the late 80’s Cool ultraviolet beam of light to vaporize Cool ultraviolet beam of light to vaporize

tissue with great precision, w/o harming tissue with great precision, w/o harming adjacent tissueadjacent tissue

Photorefractive Photorefractive KeratectomyKeratectomy

(PRK)(PRK)

2020

Photorefractive Keratectomy Photorefractive Keratectomy (PRK)(PRK)

First widely used procedure with the First widely used procedure with the excimer laser (1987)excimer laser (1987)

2121

Photorefractive Keratectomy Photorefractive Keratectomy (PRK)(PRK)

Outer layer of cornea is removed Outer layer of cornea is removed then laser is appliedthen laser is applied

vision improves as surface heals vision improves as surface heals after 4 to 7 daysafter 4 to 7 days

discomfort present during healingdiscomfort present during healing can cause corneal scarringcan cause corneal scarring

2222

PRK for MyopiaPRK for Myopia

2323

2424

Photorefractive Keratectomy Photorefractive Keratectomy (PRK)(PRK)

No microkeratome involvedNo microkeratome involved No flap createdNo flap created Ultimate visual results similar to Ultimate visual results similar to

LASIKLASIK Longer recovery period (> 2 weeks)Longer recovery period (> 2 weeks) Complications similar to LASIK; HazeComplications similar to LASIK; Haze

2525

Photorefractive Keratectomy Photorefractive Keratectomy (PRK) HAZE(PRK) HAZE

Laser In-situ Laser In-situ KeratomilieusisKeratomilieusis

(LASIK)(LASIK)LasLaser – performed with Excimer Laserer – performed with Excimer LaserIIn situ – the cornea in its natural position on the n situ – the cornea in its natural position on the eyeeyeKKeratomileusis – carving the cornea to reshape iteratomileusis – carving the cornea to reshape it

2727

LASIKLASIK

Started in 1991Started in 1991 US Clinical Trials started in 1996US Clinical Trials started in 1996 FDA approval in 1999FDA approval in 1999

2828

LASIKLASIK

Thin outer corneal flap made with Thin outer corneal flap made with high speed bladehigh speed blade

flap is lifted then laser is applied to flap is lifted then laser is applied to sculpt corneasculpt cornea

corneal flap is then returnedcorneal flap is then returned immediate visual improvementimmediate visual improvement almost no discomfortalmost no discomfort early adjustment can be doneearly adjustment can be done

2929

LASIKLASIK

3030

LASIKLASIK

3131

LASIKLASIK

3232

3333

LASIKLASIK

3434

LASIKLASIK

3535

Laser Subepithelial Laser Subepithelial Keratectomy (LASEK)Keratectomy (LASEK)

Hybrid between PRK and LASIKHybrid between PRK and LASIK ““Flap” of epitheliumFlap” of epithelium ZERO “flap” complications of LASIKZERO “flap” complications of LASIK Slightly faster recovery than PRKSlightly faster recovery than PRK Less incidence of haze than PRKLess incidence of haze than PRK Results similar to PRK and LASIKResults similar to PRK and LASIK

3636

Advantages of Excimer Advantages of Excimer LaserLaser

Safe, quick and effective if properly doneSafe, quick and effective if properly done corrects near and far sightedness and corrects near and far sightedness and

astigmatismastigmatism removes or decrease need for glasses or removes or decrease need for glasses or

contact lensescontact lenses long lasting resultlong lasting result external eye surgeryexternal eye surgery US - FDA approvedUS - FDA approved

3737

Disadvantages of Excimer Disadvantages of Excimer Laser SurgeryLaser Surgery

Not ideal for very high degrees of errorsNot ideal for very high degrees of errors relatively expensiverelatively expensive presence of surgical riskpresence of surgical risk not reversiblenot reversible glare, halo or night vision problemsglare, halo or night vision problems delayed healing or scarringdelayed healing or scarring no 100% guaranteeno 100% guarantee

3838

Am I a good candidate?Am I a good candidate?

Stable refraction Stable refraction (< 0.50 D) for at least (< 0.50 D) for at least one yearone year

Ideal ageIdeal age 18 or 21 years old and above 18 or 21 years old and above Degree of correction* :Degree of correction* :

Myopia (-0.75 to -12D)Myopia (-0.75 to -12D) Hyperopia (+6D)Hyperopia (+6D) Astigmatism (6D)Astigmatism (6D)

**depends on patient, surgeon, machine, proceduredepends on patient, surgeon, machine, procedure

3939

Am I a good candidate?Am I a good candidate?

Surgically ideal eyes :Surgically ideal eyes : Normal sized pupils < 7 mm at nightNormal sized pupils < 7 mm at night Nomal corneal thickness (> 500 Nomal corneal thickness (> 500 uum )m ) Stucturaly normal eye (not irregularly Stucturaly normal eye (not irregularly

shaped like keratoconus, etc)shaped like keratoconus, etc) Healthy pressure within the eye Healthy pressure within the eye Generaly Health eyes ( eye diseases or Generaly Health eyes ( eye diseases or

injuries that could interfere)injuries that could interfere)

4040

Am I a good candidate?Am I a good candidate?

Watch out for these health conditions :Watch out for these health conditions : pregnant, about to get pregnant or breast pregnant, about to get pregnant or breast

feeding if femalefeeding if female Collagen Vascular Diseases – Cornea has Collagen Vascular Diseases – Cornea has

collagencollagen Glaucoma or CataractsGlaucoma or Cataracts Certain corneal dystrophiesCertain corneal dystrophies Herpetic keratitisHerpetic keratitis Diabetic retinopathyDiabetic retinopathy Lupus, diabetes, rheumatoid arthritis must be Lupus, diabetes, rheumatoid arthritis must be

controlled an identifiedcontrolled an identified

4141

Other Health conditions :Other Health conditions :

Prescription Medicines that May Prescription Medicines that May Cause Problems :Cause Problems : Accutane ( for acne) – may cause severe Accutane ( for acne) – may cause severe

dry eye and decreased night visiondry eye and decreased night vision Oral Prednisone – may lower resistance Oral Prednisone – may lower resistance

to infectionsto infections UNREALISTIC expectationsUNREALISTIC expectations

4242

Is It PainfulIs It Painful

No. The eyes are numbed with No. The eyes are numbed with eyedropseyedrops

LASIK – slight pressure during suctionLASIK – slight pressure during suction After surgery :After surgery :

Some FB sensation a few hours after Some FB sensation a few hours after LASIKLASIK

Some scratchiness for 2- 4 days for PRKSome scratchiness for 2- 4 days for PRK

4343

How Long does LASIK Take ?How Long does LASIK Take ?

5-10 minutes5-10 minutes

4444

How Long will it take for my How Long will it take for my eyes to heal for LASIK?eyes to heal for LASIK?

Compared to others, it is fastCompared to others, it is fast Most postoperative discomfort and visual Most postoperative discomfort and visual

side effects are minorside effects are minor Watery sensation a few hours after surgeryWatery sensation a few hours after surgery Rarely any significant discomfort the Rarely any significant discomfort the

following dayfollowing day Good vision the following day.Good vision the following day. Vision improves for 2-6 months until stableVision improves for 2-6 months until stable

4545

When can I go back to work When can I go back to work after LASIKafter LASIK

Most patients can go back to work Most patients can go back to work the following day.the following day.

If work environment very dusty, wait If work environment very dusty, wait about 48 hoursabout 48 hours

4646

How long will the correction How long will the correction last?last?

Usually, LASIK, PRK, LASEK will correct Usually, LASIK, PRK, LASEK will correct distance vision permanentlydistance vision permanently

Eyesight changes slightly over timeEyesight changes slightly over time Not because the procedure was Not because the procedure was

unstable but because our eyes changeunstable but because our eyes change Enhancement procedures are normal Enhancement procedures are normal

(5-10%)(5-10%)

Excimer laser corneal Excimer laser corneal refractive surgery does refractive surgery does

NOT prevent or reduce the NOT prevent or reduce the risk of cataract, glaucoma risk of cataract, glaucoma and retinal degeneration and retinal degeneration

or detachment. or detachment.

Excimer laser corneal Excimer laser corneal refractive surgery does refractive surgery does

NOT prevent or treat the NOT prevent or treat the development of development of

presbyopia.presbyopia.

4949

Radial Keratotomy (RK)Radial Keratotomy (RK) MyopiaMyopia Series of 4-8 radial microscopic incisions Series of 4-8 radial microscopic incisions

on surface of Cornea to change curvatureon surface of Cornea to change curvature

5050

Radial KeratotomyRadial Keratotomy

5151

5252

Astigmatic Keratotomy (AK)Astigmatic Keratotomy (AK)

Similar to RKSimilar to RK For astigmatism onlyFor astigmatism only 1-2 incisions along periphery of 1-2 incisions along periphery of

corneacornea For pure astgmatsFor pure astgmats May be combined with LASIK, PRK, May be combined with LASIK, PRK,

LASEK, Cataract extraction.LASEK, Cataract extraction.

5353

Astigmatic KeratotomyAstigmatic Keratotomy

5454

5555

Intacs Corneal Ring Intacs Corneal Ring SegmentsSegments

FDA Approved 1999FDA Approved 1999 << 3.0 D myopia w/ 3.0 D myopia w/ << 1.0D 1.0D

AstigmatismAstigmatism 2 small plastic ring segments placed 2 small plastic ring segments placed

on periphery of corneaon periphery of cornea RemovableRemovable

5656

Intacs Corneal Ring Intacs Corneal Ring SegmentsSegments

5757

Intacs Corneal Ring Intacs Corneal Ring SegmentsSegments

5858

Intraocular Lens ImplantIntraocular Lens Implant

Placement of artificial Placement of artificial plastic lenses inside the eye plastic lenses inside the eye to correct errors of refractionto correct errors of refraction

6060

Cataract SurgeryCataract Surgery

6161

Clear Lens ExtractionClear Lens Extraction

Remove lens as in cataract surgeryRemove lens as in cataract surgery For patients > 40 y.o.For patients > 40 y.o. Disadvantage : intraocular Disadvantage : intraocular

surgery,no accomodation, risk of surgery,no accomodation, risk of Retinal DetachmentRetinal Detachment

6262

Advantages of Lens ImplantAdvantages of Lens Implant

Artificial lenses are safe and effectiveArtificial lenses are safe and effective good for high degrees of errorsgood for high degrees of errors minimal visual distortionsminimal visual distortions near immediate resultnear immediate result lifetime effectlifetime effect no maintenanceno maintenance reversible and adjustable (some types)reversible and adjustable (some types)

6363

Disadvantages of Lens Disadvantages of Lens ImplantImplant

Internal eye surgeryInternal eye surgery greater surgical riskgreater surgical risk risk of late retinal detachmentrisk of late retinal detachment risk of late corneal damagerisk of late corneal damage relatively expensiverelatively expensive

6464

Phakic Intraocular Lens (PIOL) Phakic Intraocular Lens (PIOL) ImplantsImplants

For extreme nearsightedness For extreme nearsightedness ( greater than -12D to -15D) / ( greater than -12D to -15D) / farsightedness (greater than +4D to farsightedness (greater than +4D to +6D )+6D )

Advantage : maintains accomodationAdvantage : maintains accomodation Disadvantage : may develop Disadvantage : may develop

cataracts;endophthalmitiscataracts;endophthalmitis

6565

Phakic Intraocular Lens (PIOL) Phakic Intraocular Lens (PIOL) ImplantsImplants

6666

BiopticsBioptics

Phakic IOL implant then LASIKPhakic IOL implant then LASIK When neither technique alone worksWhen neither technique alone works Can correct more than 30D of Can correct more than 30D of

myopiamyopia

6767

HYPEROPIAHYPEROPIA

6868

PRK for HyperopiaPRK for Hyperopia

6969

Laser Theramal Keratoplasty Laser Theramal Keratoplasty (LTK)(LTK)

FDA approval Jan 2000FDA approval Jan 2000 Holmium laser – deliver laser energy Holmium laser – deliver laser energy

to periphery of corneato periphery of cornea For Hyperopia (0.75 to 2.5 D)For Hyperopia (0.75 to 2.5 D) Takes months to stabilizeTakes months to stabilize In time, the effect wears off in a In time, the effect wears off in a

substantial number of casessubstantial number of cases

7070

Laser Theramal Keratoplasty Laser Theramal Keratoplasty (LTK)(LTK)

7171

Conducktive Keratoplasty Conducktive Keratoplasty (CK)(CK)

A special probe introduces electrical A special probe introduces electrical current to the peripheral cornea, current to the peripheral cornea, shrinking the collagen to tighten the shrinking the collagen to tighten the cornea and make it steeper centrallycornea and make it steeper centrally

FDA approved 2002FDA approved 2002

7272

Conducktive Keratoplasty Conducktive Keratoplasty (CK)(CK)

7373

Conducktive Keratoplasty Conducktive Keratoplasty (CK)(CK)

7474

PresbyopiaPresbyopia

To date, there is still NO widely To date, there is still NO widely accepted, safe and effective accepted, safe and effective permanent treatment for this permanent treatment for this conditioncondition

7575

Surgery for PresbyopiaSurgery for Presbyopia

Anterior Ciliary Anterior Ciliary Sclerectomy (ACS)Sclerectomy (ACS)

Scleral Expansion Scleral Expansion Bands (SEBs)Bands (SEBs)

7676

VIDEOVIDEO

What is best for you?What is best for you?

Consider your personal Consider your personal preference and lifestyle. preference and lifestyle.

7979

THANK YOU