Author Roger F Steinert MD Dr Steinert is a paid Medical Monitor for ReVision Optics Methods Three Optical Approaches Near Power in Pupil Center Distance Power in Pupil Center Pinhole Effect ID: 318495
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Slide1
Options For Corneal Correction of Presbyopia
Author: Roger F. Steinert, M.D.
Dr. Steinert is a paid Medical Monitor for ReVision OpticsSlide2
Methods: Three Optical Approaches
Near Power in Pupil Center
Distance Power in Pupil Center
Pinhole EffectSlide3
LASIK
Excimer ablation implemented with either PRK or LASIK is used to alter the anterior corneal surface, creating either a “near center” or “distance center” ablation profiles.Not FDA approved.
US Patent 6 280 435 B1
US Patent 6 969 386 B2Slide4
Femtosecond Laser Corneal Weakening
The INTRACOR® (Technolas Perfect Vision) procedure causes steepening of the central cornea by cutting a set of concentric cylinders. The width of the cylinders is very small, resulting in minimal loss of corneal tissue. The cuts begin below Bowman’s layer and extend through most of the stromal thickness (see cross-sectional sketch below). The cylindrical boundaries facilitate remodeling of the stroma, causing an increased central corneal curvature and a resulting near center zone.
Not FDA approved. Slide5
Pinhole Corneal Inlay
The KAMRA™ (formerly
AcuFocus
) intracorneal inlay is an opaque,
polyvinylidene
flouride
, 3.8 mm diameter ring with a 1.6 mm diameter central opening. It is 5 microns thick and the body is fenestrated with 8400 randomly placed holes to facilitate nutritional flow.
Application of the pinhole effect to the human dioptric awaits the judgment of the ongoing US Clinical trial (KAMRA™ ).
KAMRA™ Corneal Inlay
Contact LensSlide6
Refractive Corneal Inlays
The PresbyLens® (ReVision Optics®) is a clear, 2 mm diameter, sub 50 micron thick, hydrogel inlay placed under a LASIK-like flap, which steepens the central corneal curvature – creating a near center zone. The inlay has no intrinsic power ; its index of refraction is the same as the cornea’s.
In FDA clinical trial.
The Flexivue™ (Presbia™) intracorneal micro-lens is a 3 mm diameter, hydrophilic polymer disk with a 20 micron edge thickness. The center has no intrinsic power, creating a distance center zone for emmetropes, while the peripheral “donut” has additional intrinsic refractive power for near.
Not FDA approved
.
PresbyLens
InlaySlide7
Results: Uncorrected Near VA in Treated Eye
Near Center LASIK Profile: 6m Data; (1) J Ref Surg, 2009 25(1-suppl) : S148-S155
Near Center LASIK Profile: 6M Data; (2) J Cataract Ref Surg, 2008 34(2): 205-210
Near Center Stromal Relaxing Profile (Intracor): 3M Data; (3) J Ref Surg, 2009 25(10): 855-861
Pinhole Mechanism (AcuFocus): 24 M Data; (4) J Ref Surg, 2010 26(10): 707-715
Near Center Corneal Elevation Change (PresbyLens): 3M Data; (5)
ReVision
Optics, September 2010Slide8
Results: Uncorrected Intermediate VA in Treated Eye
Pinhole Mechanism (AcuFocus): 24 M Data; (4) J Ref Surg, 2010 26(10): 707-715
Near Center Corneal Elevation Change (PresbyLens): 3M Data; (5) ReVision Optics, September 2010Slide9
Results: Uncorrected Distance VA in Treated Eye
Near Center LASIK Profile: 6m Data; (1) J Ref Surg, 2009 25(1-suppl) : S148-S155
Near Center Stromal Relaxing Profile (Intracor): 3M Data; (3) J Ref Surg, 2009 25(10): 855-861
Pinhole Mechanism (AcuFocus): 24 M Data; (4) J Ref Surg, 2010 26(10): 707-715
Near Center Corneal Elevation Change (PresbyLens): 3M Data; (5) ReVision Optics, September 2010 Slide10
Results: Technique Comparison
Easily Reversible
Maximizes
Available Light
“Wow” Factor
(Rapid
Visual Improvement
)Cosmetic Appeal
Refractive Inlays
Pinhole Inlays
______
___PresbyLASIK / PRK
___
___
Laser Remodeling of Stroma
___Slide11
Conclusions:
All procedures examined provide a clear improvement in uncorrected near acuity, with only a minor loss in uncorrected distance acuity.
Of the solutions discussed, the
PresbyLens
® appears to give best correction of near and intermediate vision whereas
PresbyLASIK
from
Nidek results in the least loss of distance vision.Very good near and intermediate visions provided by hydrogel corneal inlays, as well as reversibility, are attractive though very long term biocompatibility is yet to be proved. “Wow factor” is a plus.
The reversibility of pinhole inlays is attractive though very long term biocompatibility is yet to be proved and reduced light may result in reduced vision in low light.Use of a femtosecond laser system alone is attractive though long-term corneal stability is yet to be proved and reversibility may prove
difficult. “Wow factor” is a plus. Not compatible with prior or simultaneous LASIK.LASIK solutions are attractive though reversing the procedure may prove difficult and stability may be suboptimal.