Post on 03-Jul-2020
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VISION DETERIORATION AFTER MULTIFOCAL INTRAOCULAR LENS
IMPLANTATION
Aylin Kılıç, MD
Asst Proffesour of Ophthalmology
Medipol University, İstanbul
Visual problems after MFIOL
• Early Period (1 month )
• Patient physicologic problems– Depression– Demanding attention– Obsession
• IOL design related– Trifocal / bifocal / EDOF– Glare / halo– Old generation diffractive surface
• Residual refractive error – Biometry, calculation mistakes
• Dry eye
Visual problems after MFIOL
• Late Period
• Dry eye
• Ocular problems: high IOP, retinal edema, zonule dehicence– MFIOL may not tolerate minimal decentration or edema
• Posterior capsule opasification,
• Capsule contraction syndrome, tilted IOL– MFIOL more sensitive than monofocal
• 53 years old, male
• OD: 0,7 OS: 1.0 (snellen)
• emmetrop
• Bio and fundus : N
MFIOL, Postop 1 month visit:I cannot see with right eye !!
WHEN ? immediate after surgery
• 45 years old, male
• OD: 0,2 OS: 1.0 (snellen)
• emmetrop
• Bio: N
MFIOL OD, Postop 1 month visit:I had perfect vision, but recently I cannot see !!
WHEN ? 3 weeks after operation
Transient visual loss after MFIOL
• Precorneal film is very important for MFIOL optic performance
• Daytime visual loss• Dry eye is the most common reason ! in old patients
– After surgery steroids, antibiotics, NSAI may cause extra dryness ..
• Meibomitis, blepharitis
• Tear break up time, meniscus
I cannot drive at nights !!mainly 2 reasons
Halo / glare
• IOL design
• Pupil dependency
refractive/diffractive surface
Refractive error
• Biometry mistake
• Check SUBJECTIVE refraction
• DON’T trust autorefractometer
Dysphotopsia and MF IOLs
• Unwanted images
• Each MF IOL design uses a different strategy to produce simultaneous near and distance images.
• When the pupil expands in dim light, more light is permitted to come through the peripheral zone
Halo / Glare /Dysphotpsia
• Photic phenomena
X 3,5 times more in MFIOL vs monofocal
• 7 % of eyes required IOL exchange in old generation diffractive
( Woodward et al J Cataract Refract Surg 2009;35(6):992-997.)
What the patient sees ?
• Temporal darkness• Nose blocks vision nasally• High plus IOLs• High refractive index
• Scintillating vision• High refractive index
• Arc• Capsule overlaps the IOL edge
• Flare• Scotopic symptom, produced by come• Correcting astig or myosis
• Central flash• Edge design
• Haloes
Astigmatism in MFIOL
• Small amount of astigmatism in eyes with MFIOL
– poorer optical quality,
– compromised distance and intermediate visual acuities,
– greater halo effect
HayashiK,ManabeS-i,YoshidaM,HayashiH.Effectofastig- matism on visual acuity in eyes with a diffractive multifocal intraocular lens. J Cataract Refract Surg 2010; 36:1323–1329 .
• RESIDUAL AMETROPIA/ASTIGMATISM
after MFIOL
64%
de Vries NE, Webers CAB, Touwslager WRH, Bauer NJC, de Brabander J, Berendschot TT, Nuijts RMMA. Dissatisfaction
after implantation of multifocal intraocular lenses. J Cataract Refract Surg 2011; 37:859–865.
MFIOLs are more sensitive to posterior capsul opacification
• Loss of contrast sensitivity• Vision quality, halo
Significant PCO was found;
• 54% of eyes with blurred vision and • 47% of eyes with photic phenomenon
( Woodward et al J Cataract Refract Surg 2009;35(6):992-997.)
• Cornea scars and pterygia requires treatment before MFIOLs.• Remove opacification• Achieve regular keratometric values• Asymptomatic peripheral scars are not contraindicated
Corneal Aberrations and MFIOLs
• Whenever a corneal aberration such as coma, spherical aberration or first order ast is increased from zero, a proportionate decrease in contrast follows.
MFIOL is best when …
• Spherical equivalent (SE) is close to plano
• Postoperative regular corneal astigmatism is 0,5 or less
Contraindication
• Keratoplasty• Radial keratotomy• LASIK ?• PRK ?
Placing a MFIOL behind a multifocal cornearuns the risk of additional loss of contrast and reduction in visual quality.
MFIOL after LASIK
• Myopic LASIK induces positive spherical aberration: ASPHERIC MFIOLs
• Hyperopic laser correction induces negative values: SPHERIC MFIOLs
• A spherical multifocal IOL in eyes with hyperopic LASIK compensates the negative spherical aberrations.
MFIOL calculation after LASIK
• Less predictable outcomes: • because all standard formulas for IOL power calculation are
based on keratometric values.
• A major factor in the miscalculation of IOL power • In irregular corneas is the wrong practice of measuring only
the anterior surface with keratometry or corneal topography.
• Due to the altered anterior/posterior corneal curvature relationships after excimer laser vision correction, the keratometer will overestimate corneal power in previously myopic eyes and underestimate
Pupil size and MFIOL
• Large pupil : more glare
• Irregular pupil; atrophic iris, iatrogenic mydriasis, eccentric pupil contraindicated.
Zonullar Issues
• Decentered-tilted MFIOL;• Decreased contrast sensitivity
• Aberrations
• Decreased VA
• Decreased optic quality
Vision deterioration after MFIOL;
• History;– Preexisting ambliyopia/Strabismus– Preoperative VA– Complaints began immediately ? Or change within
time ?
• UCVA, BCVA• Corneal topography• Dry eye ? Meibomitis?• IOP measurement• Retina/OCT
Unhappy Patient;
• Ametropia
• Posterior capsule opacification
• Photic phenomena due to tilt/decentration
• Retained lens fragment
• Large pupil
Conclusion:
• Visual complaints will be after MF IOL ☺
• Refractive error after MF
• Dry eye
• MF IOL design are most common reasons ,
• and solutions are possible..