2. Monovision
• This optical condition allows the relief
of presbyopia symptoms.
– one eye is corrected for distance vision
– The other eye is corrected for near vision
• Goal of treatment
– To give patients clear vision both near and
far
3. Concept
• Intention to produces anisometropic blur
– the image in one eye is focused while the
image in the other eye is defocused.
– Suppress blur in nondominant eye will be
easier than in dominant eye.
• Person'€™s brain learns to use the
distance focused eye for distance viewing
and the near focused eye for near viewing
4. Monovision
• Dominant eye corrected for distance vision
• Nondominant for near vision
• Induced anisometropic 1.25- 2.5 dipoters
• Mini monovision lower level of myopia
for near vision -0.5 to -0.75 D
5. Ocular dominanceOcular dominance
Ocular dominanceOcular dominanceOcular dominanceOcular dominance
MotorMotorMotorMotor
Pointing-a-finger testPointing-a-finger test
Hole- in- card testHole- in- card test
Pointing-a-finger testPointing-a-finger test
Hole- in- card testHole- in- card test
Binocular rivalry targetBinocular rivalry target
Stereodisparate objectsStereodisparate objects
Binocular rivalry targetBinocular rivalry target
Stereodisparate objectsStereodisparate objects
sensorysensorysensorysensory
Seijas O, Liano P, Liano R, Roberts C, Piedrahita E, Diaz E. Ocular Dominance Diagnosis and Its Influence in
Monovision. Am J Ophthalmol.2007;144:209–16.
6. MotorMotor testtest
Seijas O, Liano P, Liano R, Roberts C, Piedrahita E, Diaz E. Ocular Dominance
Diagnosis and Its Influence in Monovision. Am J Ophthalmol.2007;144:209–16.
9. Method
• Test dominant eye
• Refraction
– Dominant Full correction for distance vision
– Nondomiant Myopia undercorrection
Hyperopia overcorrection
• Trial Lens or CL trial at home
adaptation period should be greater than 2-3 wks
10. How is monovison obtained?
• Contact lenses
• Refractive surgery
• Conductive Keratoplasty
• Corneal inley
• IOL
11. Refractive surgery
• Multifocal corneal ablation
o A small central steep zone
o Inferior near zone ablation pattern
o Inferior decentered hyperopic ablation
o Central distance ablation with
intermediate/near midperipheral abration
13. Conductive Keratoplasty
• Nonablation collagen-shrinking procedure
approve for correction low level of
hyperopia ( +0.75 - + 3.25 D)
• Radiofrequency(RF) energy is delivered
through tip into peripheral corneal stroma
14.
15. Intracorneal Inlays
• Lamellar corneal flap created (8.0mm and 160µm)
• Placing a biocompatible polymer lens in the central
cornea over pupil
16.
17. Corneal inley
• Pros
Extraocular
Easy to do
Easy to reverse
• Cons
Involves visual axis
Adversely effects distance vision in emmetropes
Cases of epithelial ingrowth resulting in thinning
and melt of flap
19. Monovision
• Success rate mean 76%
Depend onDepend on
• Ocular dominance and sighting preference
• Interocular suppression of blur
• Age
• Stereoacuity
• phorias
Jain S, Arora I, Azar D. Success of Monovision in Presbyopes: Review of theLiterature and Potential Applications
toRefractive Surgery. Surv Ophthalmol.1996;40:491-99.
20. Patient selection
• Best candidate are myopic patient over
the age of 40
• Age & near addition of the patient can be
predictive of success
• Visual needs & lifestyle, occupation,
patient’s expectation
22. Disadvantages of Monovision
• ↓ in visual acuity, stereopsis, depth
perception, contrast sensitivity
• Difficulty in seeing clearly at an intermediate
distance
• Driving is compromised, especially at night
• Distance and near ghosting (incomplete
suppression of interocular blur)
23. Modified monovision
• Dominant eye distance vision
• Nondominant eye bifocal Lens
near and intermediate distance
Modified trivision
• Dominant eye distance vision + low add
power for intermediate distance
• Nondominant eye bifocal Lens
near and intermediate distance
24. Varies Forms and Examples of Modified
Monovision
Distance EyeDistance Eye Near eyeNear eye
Single-vision lens Bifocal lens power biased
toward near vision
Bifocal lens power biased
toward distance vision
Bifocal lens power biased
toward near vision
Large OZ for distance/center Small OZ for distance/center
Small OZ for near/center Large OZ for near/center
25. Varies Forms and Examples of Modified
Monovision
Distance EyeDistance Eye Near eyeNear eye
distance/center concentric or
progressive lens
near/center concentric or
progressive lens
Low segment height for
translation
High segment height for
translation
Monofocal lens, concentric
progressive, or concentric
lens
Concentric near/center lens
with large OZ, or
distance/center lens with
small OZ
31. The ARRAY®
IOL
Refractive Multifocal IOL Design
• Five concentric zones
• Each zone has a near or
distance weighting
• Centre is distance weighted
32. 3rd
(distance dominant) ring enlarged and moved
3.4mm-3.9mm to 3.45mm-4.3mm
4th
(near dominant) ring shifted from
3.9mm-4.6mm to 4.3mm-4.6mm (and thinned
out)
33. AMO ReZoom™
Good:
• Provides excellent distance vision
• Provides reasonable intermediate vision
• Fewer halo and glare problems than the Array
Not-so-good:
• Reading ability (near acuity) variable
• Reading ability is pupil dependent
• Less tolerable in myopes
38. Alcon ReSTOR: Partial Optic Diffractive
Apodized
• Only the central 3.6mm of optic contains diffractive
rings with steps of certain height
• Now available in aspheric form
• Step heights get progressively lower from centre to
periphery
39. AMO Tecnis™
ZM900 Multifocal and Alcon ReSTOR
Good:
• Provide excellent distance and near vision
• Fewer halo and glare problems than the Array
• Most appreciated by hypermetropes
• Well tolerated by (higher) myopes
Not-so-good:
• Intermediate vision suboptimal: problem for computer
users
• Quality of vision not as acute as with a monofocal
(contrast sensitivity suffers)
40. REFRACTIVE MULTIFOCAL IOLS DIFFRACTIVE MULTIFOCAL IOLS
Excellent intermediate and distance vision Excellent reading vision and very good
distance vision
Near vision fair but may not be sufficient to
see very small print
Fair Intermediate vision
Patients who read for prolonged periods of
time or in poor lighting may experience eye
fatigue.
Patients who do lots of computer work may
not accept it well
PUPIL DEPENDENT LESS DEPENDENT ON PUPIL
Refractive vs Diffractive
MULTIFOCAL IOLs
41. Disadvantages
• Reduction of contrast sensitivity
• Glare, haloes
• Less satisfactory visualization of fundus- difficulty in vitreo-retinal procedures
• Requires Visual-Cortical Neuro-adaptation
• Requires
• Accurate biometry
• Precise IOL implantation
• Astigmatic reduction
MULTIFOCAL IOLs
The Array is a refractive IOL with five zones all offering near, intermediate and distance vision utilising 100% of available light. Zones 1,3 and 5 are weighted for distance and 2 and 4 are weighted for near.
