VFL 3

VFL 3 lenses provide an ideal balance of distance, intermediate and near vision. This design provides a progressive range of focal powers enabling the presbyopic eye to selectively focus at any distance within the power range of the VFL 3 optical system. These lenses are not translating bifocals but rather simultaneous multifocals. The lens optical center must be positioned directly in front of the pupil for best results at all distances. These lenses are capable of focusing at any distance from 40cm to 20 feet and beyond. Your patients will be able to focus on near reading tasks, or their computer screen, or an object across the street.


VFL 3 multifocals do not have a single add power, but rather a progressive range of add powers from approximately +0.75 to +2.00. This power range will normally satisfy the add requirements of emerging and moderate presbyopes. For advanced presbyopes, VFL 3 with HD-AP will extend the total add power. HD-AP is a supplemental add applied to the front surface of a standard VFL 3 lens. HD-AP is pupil size and lens position dependent.




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ParameterOptions
Materials:Call for Options
Progressive Add<+2.00 VFL 3
>+2.00 VFL 3 HD-AP
Base Curve Range6.80 - 7.90*
PeripheryHPC 65*
Distance Powers+10 to -10*
Diameters9.0 to 9.4*
TintCall for Options
* (Custom parameters available)
trans
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The progressive power gradient of a VFL 3 lens is derived from a progressive flattening posterior surface combined with a single spherical anterior surface. The aspheric posterior surface not only contributes to the progressive power effect but significantly influences the fitting approach required to achieve a successful lens to cornea fitting relationship. The sagittal depth of a VFL 3 lens is greatly reduced due to the progressive flattening of the posterior surface. Axial edge lift increases as the posterior surface flattens. In order to offset this rapid flattening the apical radius (base curve at it's steepest point) must be fit considerably steeper than the flattest corneal meridian. Most patients are fit approximately 2.50 to 3.00 diopters steeper than the flattest corneal meridian.


Example:43.00@180 / 44.50@090 Keratometer
"K" 43.00 +2.50 = 45.50 D or 7.40mm

In the example a base curve has been selected 2.50 diopters steeper than "K". A VFL 3 lens fit 2.50 diopters steep will align with the intermediate and peripheral corneal surface. A small area of central clearance is characteristic of a normal VFL 3 fit. This central clearance forms a significant plus tear lens between the base curve of the contact lens and the anterior surface of the cornea. This plus tear lens must be neutralized by adding an equal amount of minus power to the contact lens. An over-refraction is the most accurate way to determine the required lens power. An approximation of the anticipated lens power can be made by using normal SAM/FAP rules. This plus tear lens compensation is the reason why the power of a VFL 3 lens is normally 2.00 to 2.50 diopters more minus than the patient's refractive error.




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Flat KVFL 3 Base Curve*VFL 3 Diameter
42.00D7.60 mm9.4 mm
42.507.509.4
43.007.409.2
43.507.309.2
44.007.259.2
44.507.159.2
45.007.109.2
45.507.009.0
46.006.959.0
46.506.859.0
* With the rule corneal astigmatism greater than 2 diopters, against the rule, oblique or other corneal topography may require a base curve steeper than the normal suggested starting point. Tight or narrow lid apertures may also require a steeper base curve selection. A .10mm base curve change is required to produce a significant on eye affect.
flat
Steep Fit - Unacceptable
flat
Flat Fit - Unacceptable
flat
Good Fit
  • Slight inferior position.
  • Pronounces central pooling.
  • Harsh intermediate bearing.
  • Inadequate peripheral clearance.
  • Flatter base curve indicated.
  • Superior.
  • Thin pattern over pupil due to decentration.
  • Excessive peripheral clearance (stand-off).
  • Steeper base curve indicated.
  • Well centered.
  • Slight central pool.
  • Uniform mid-peripheral alignment.
  • Peripheral clearance.
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Select VFL 3 trial lenses based on the preceding base curve chart. VFL 3 must center well to achieve best-fit and visual results. If the trial lens doesn't center or moves excessively, steepen the base curve .10mm. If unable to achieve acceptable centration through the suggested corrective action below, or you would like to discuss other potential parameter changes call consultation at :

1-800-426-1700

Lens PositionCauseCorrective Action
fg1Flat base curveVerify with fluorescein
Steepen base curve .10mm
Thick minus edgeLenticular plus carrier or C/N
Large diameter
Narrow aperture
Reduce diameter 0.4mm
Corneal Topography
Steep base curve
Add 1 prism BD
Flatten base curve .10 mm
Lens PositionCauseCorrective Action
fg1Steep base curveVerify with fluorescein
Flatten base curve .10mm
Center thicknessLenticular minus carrier
Small diameterIncrease diameter 0.4mm
Flat base curveVerify with fluorescein
Steepen base curve .10mm
Lens PositionCauseCorrective Action
fg1A/R astigmatismSteepen base curve .10mm
Increase diameter 0.4mm
Narrow apertureDecrease diameter 0.4mm
Steepen base curve .10mm
Lens PositionCauseCorrective Action
fg1Oblique astigmatismSteepen base curve .10mm
Increase diameter 0.4mm
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VFL 3 Over-Refraction Procedures

  1. Allow at least 15 minutes for VFL 3 trial lens to equilibrate. Trial lenses must center well in order to achieve an accurate over-refraction.
  2. Over-refract with phoropter to determine best binocular distance correction.
  3. Transfer distance over-refraction to a trial frame and test the patient's distance and near vision, binocularly.
  4. Add additional plus power to the trial frame, binocularly, in +0.25 increments to enhance near vision as needed. As each increment of plus is added, ask the patient to refer back to the distance chart. This will enable you to determine the maximum plus your patient will accept at distance.
  5. It is important to work in +0.25 increments in order to achieve the best near vision without overplussing distance. The near / far balance is critical to the success of your patient. Most patients will accept more minus at distance and more plus at near than should be prescribed. Your objective is to find the balance that satisfies both distance and near. Caution - If the patient's vision is plussed to an unacceptable level in order to achieve acceptable vision at near, call consultation to discuss the additional add capabilities of the VFL 3 HD-AP.
  6. Combine all add powers for each eye as follows:
    ODOS
    VFL 3 trial lens-3.00-3.00
    Distance OR-0.75-1.00
    Near OR+0.25+0.50
    Power to order-3.50-3.50

flat

good fit

flat

flat fit

flat

steep fit