Transcript Comparison of visual function between phakic eyes and

Effect of astigmatism on visual acuity
in eyes with a diffractive multifocal
intraocular lens
Ken Hayashi, MD
Motoaki Yoshida, MD
Shin-ichi Manabe, MD
Hideyuki Hayashi, MD
Hayashi Eye Hospital, Fukuoka, Japan
The authors have no financial interest in any
of the materials mentioned in this paper.
Purpose
Our previous study showed that postoperative
refractive astigmatism significantly affects the
visual function in eyes with a refractive-type
multifocal intraocular lens (IOL). The purpose
of this study was to examine the effect of
refractive astigmatism on visual acuity from
far to near distance in eyes with a diffractivetype multifocal IOL.
Patients
• 96 patients scheduled for bilateral cataract surgery
1) Diffractive multifocal IOL with +4.0 D add power
(Alcon ReSTOR 4D; SN6AD3) --- 32 patients
2) Diffractive multifocal IOL with +3.0 D add power
(Alcon ReSTOR 3D; SN6AD1) --- 32 patients
3) Monofocal IOL with the same material and design
(Alcon SN60WF) --- 32 patients
• Not randomized because of ethical reasons
• Only the first-operated eye
• Exclusion criteria: 1) severe pathology of the optic nerve,
macula, and cornea, 2) corneal astigmatism ≥ 1.5D, 3)
history of ocular surgery, and 4) irregular-shape pupil
Methods
Simulation of astigmatism
1) Various diopters (0D, 0.5D, 1.0D, 1.5D, and 2.0D)
of cylindrical lens were added at the 90° meridian
2) Only an against-the-rule astigmatism
Examination
1) Distance-corrected visual acuity (VA) from far to
near (KOWA AS-15)
2) Manifest spherical equivalent value
3) Keratometric cylinder
4) Pupillary diameter‥ Colvard pupillometer
*Examined at approximately 3 months after surgery
Change in all-distance visual acuity by diopters of
added astigmatism in the ReSTOR+4D group
Change in all-distance visual acuity by diopters of
added astigmatism in the monofocal IOL group
Comparison of all-distance visual acuity
in the three IOL groups
Comparison of all-distance visual acuity
in the three IOL groups
Comparison of all-distance visual acuity
in the three IOL groups
Comparison of all-distance visual acuity
in the three IOL groups
Eyes achieving a visual acuity of 20/40 at
both far and near by IOL group
ReSTOR 4D ReSTOR 3D
Monofocal
P value
0D
30 (100%)
30 (100%)
3 (10.0%)
< .0001*
0.5D
30 (100%)
26 (86.7%)
2 (6.7%)
< .0001*
1.0D
26 (26.7%)
20 (66.7%)
5 (16.7%)
< .0001*
1.5D
12 (40.0%)
6 (20.0%)
5 (16.7%)
.0812
2.0D
1 (3.3%)
2 (6.7%)
3 (10.0%)
.5853
*Number of eyes in monofocal IOL group were
significantly less than in both multifocal IOL groups
Conclusions
1) When postoperative astigmatism is
approximately within 1.0D, the diffractive
multifocal IOL provided useful far and near
VA.
2) With astigmatism of 1.0D or less, near VA or
intermediate VA with the diffractive multifocal
IOLs was better than that did with the
monofocal IOL.
3) Eyes with astigmatism of approximately 1.0D
or less are definitely candidates for
implantation of a diffractive multifocal IOL.