LASIK: How It’s Done

Vincent J. Marino, D.O. FAOCOMedical Director, LASIKPlus Cincinnati & Dayton, OH

7840 Montgomery Rd. Cincinnati, OH 452366470 Centerville Business Parkway, Centerville, OH 45459

LASIK: How It’s DonePretest Question #1

What percentage of LASIK patients achieve uncorrected visual acuity of 20/40 vision or better? A. 99% *B. 94%C. 75%D. 50%

LASIK: How It’s DonePretest Question #2

• What group below best describes the population that acquires presbyopia (age related loss of near vision)?

A. Presbyopia only effects some people over the age of 40.

B. Presbyopia effects all individuals over the age of 40 regardless of glass prescription. *

C. Presbyopia only happens to your parents.D. Myopic (nearsighted) individuals can not become

presbyopic.

20th Annual Grandview Family Practice Conference

February 20, 2015 • Vincent J. Marino, DO• 1992 - Nova Southeastern University College of

Osteopathic Medicine • 1993 - Internship Grandview Hospital • 1996 - Residency Ophthalmology Grandview

Hospital • Fellow American Osteopathic College of

Ophthalmology• 1996 – Present, LASIKPlus Cincinnati & Dayton,

OH • Experience 86,000 LASIK surgeries

LASIK• LASIK: acronym l(aser) as(sisted) i(n-situ)

k(eratomileusis)• eye surgery to correct vision in which a laser

reshapes the inner cornea.

Why does one undergo elective refractive

surgery?

• Has a Myopic, Hyperopic, Astigmatic refraction (glasses Rx).

Why does one undergo elective refractive

surgery?

• Tired of wearing glasses• More than 150 million Americans use corrective

eyewear to compensate for refractive errors. 1

Why does one undergo elective refractive

surgery?

• Contact lens intolerant or over wears contact lenses. • More than 30 million people in the U.S. wear contact

lenses. • Serious eye infections that can lead to blindness affect

up to 1 out of every 500 contact lens users per year.• Not following proper contact lens care instructions• Between 40%-90% of contact lens wearers do not

properly follow the care instructions for their contact lenses.

• Improper cleaning and irregular replacement of contact lenses and contact lens cases—as well as other behaviors relating to contact lens hygiene and care—have been linked to a higher risk of complications.

Why does one undergo elective refractive

surgery?

• Activities that makes contacts or glasses hard to wear

• Job (firefighting, police), Military, sports

History of refractive surgery 4

• 1988 Marguerite B. McDonald, MD First PRK • 1989 Gholam A. Peyman, MD patent on flap

production

• 1999 LASIK formally approved by the FDA

Elective surgery

• LASIK is the world’s most popular elective procedure—more than 28 million LASIK procedures have been performed worldwide.

Candidacy

• Good medical health, good ocular health, good topography, good pachymetry (corneal thickness)

• > 18 years and stable refraction• Insure that healing for an elective surgery may go

well.• Rx in range =/- 0.75D or greater.• Up to -11.00 Diopers of Myopia• Up to +5.00 Diopters of Hyperopia• Up to -6.00 Diopters of Astigmatism

Candidacy• Refractive Range• Measured in units of optical units Diopter (D)

o 1 Diopter = 1/meter (f)

<--------(+6D)------hyperopia--------0--------myopia-------- (-11D)------->

Emmetropia = +/- 0.5 D

Astigmatism 0 ------------------------------(-6 D)------>

Evaluation

• Medical and family history • Dilated eye exam• Refraction objective and subjective • IOP (intra ocular pressure)• Corneal Topography • Aberrometry• Pachymetry (corneal thickness)

EvaluationTopography

EvaluationAberrometry

Consent • Goals and expectations (20/40 or better, most will

achieve 20/20 or better)• Review enhancement limits, may do second

surgery if Rx drifts (3-4%) if Rx drift. Usually less than one Diopter.

• Presbyopia education (over 40 years, need reading glasses if both eyes are corrected for distance).

• Monovision option• Review risk, benefits and alternatives

Presbyopia• Near Vision reflexoConvergenceoPupil constrictionoAccommodation• Loss of accommodation due to age = presbyopia

Presbyopia• Loss of near vision due to age

o Loss of accommodation (focusing power) o All individuals regardless of refractiono 40 years and oldero Progressive

• Results from the thickening and loss of flexibility of the natural lens• Stabilizes in mid-sixties

o Myopes with a refractive range of -1.00 to -3.00 diopter can read without glasses.• Myopes become presbyopic and experience blurred vision at near

with their spectacle (eye glass) correction.

Presbyopia Monovision

• Optional treatment method to decrease the dependence on glasses for both distance and near vision for individuals over 40 years.

• Dominant eye is corrected for distance• Non Dominant eye is corrected for near• Monovision can be set up with contact lenses or

LASIK• “Blended vision”• Functional vision, not perfect at distance or near.• Compromise, “best of both worlds”.• Monovision patients may require part time glasses for driving and fine

near vision.

Equipment

• Flap production• Femtosecond laser VS Microkeratome• Microkeratome: Buttonhole, partial flap, suction

loss, less stable refractive outcome re non-planar flap (thinner in the middle)

 • Femtosecond laser: scars may yield incomplete

flaps but are rare. Able to reapply suction after suction loss and complete flap. More stable refractive outcomes. Lower incidence of dry eye. Ability to produce thinner flaps to conserve corneal tissue and provide higher refractive treatments.

Surgery

Microkeratome blade inspection

Surgery Microkeratome

assembled

SurgeryFemtosecond laser

Equipment Femtosecond laser

SurgerySurgical instruments

Excimer laser • Visx, • Wavelight

Surgery

• Proparicaine anesthetic • drops last 30 minutes

Surgery

• Flap production

Surgery• Flap dissection and lift

Surgery• Excimer laser • refractive ablation

Surgery• Flap reposition

Surgery• Removal of debris• Slit lamp

Surgeryflap production suction

ring

Surgeryflap production suction

ring

Surgeryflap production

docking

Surgeryflap production

docking

Surgeryflap production

Surgeryflap production

Surgeryflap production

Post Operative follow up and care

• Rest for four hours with eyes closed mild burning expected

• No eye rubbing• No swimming or hot tubs for one week• Inflammation and infection warning signs given• Diving vision expected at day one• Antibiotic and steroid drops for one week

Recovery

• Post Operative follow up and care:• Rest for four hours with eyes closed mild burning

expected• Diving vision expected at day one• Antibiotic and steroid drops for one week

Recovery• Most patients achieve 20/40 to 20/20 (driving

vision) the next day. Most patients report near glasses like vision on day one. The quality of their vision improves dramatically through the weeks one to 12. Complete refractive stability occurs at about one year.

Recovery• Patients are instructed not to rub their eyes for

one week to prevent the flap from being dislodged (a rare complication but easily repaired). Protective safety glasses are worn during sleep for the first week.

Post Operative follow up and care

• One day o Ensure that the flap is in good positiono Dry eyeo inflammationo Infection 

• One montho Refractive outcomeo Dry eye

• Three monthso Refractive outcomeo Dry eye

• Annual examso Insure good ocular health and refractive stability

Outcomes

• 94% 20/20 or better• 99% 20/40 or better• 3-4 % enhancement rate (second surgery)

o Uncorrected visual acuity 20/30 or worseo Manifest (subjective) refraction +/- 0.75 Diopterso Difficulty with night vision o Refractive shift over timeo residual refraction

Patient satisfaction

• 95% of patients are satisfied and have no further need for additional surgery.

• 3% require enhancement (second surgery)o Reasons: patient expectations and refractive shift.o most second surgeries occur years to decades

secondary to small Rx shifts.

Complications

• Dry eye• Diffuse Lamellar Keratitis• Ectasia• Flap Complications• Suspicious settings

Future of LASIK

• Topography guided treatments for asymmetric corneas

• cross linking for ectasia and keratoconus

PRK

• Surface laser without the flap