Bi-Aspheric multi-focal Lens (3E/EE-FOCUS)
3E/EE-FOCUS is a revolutionary multi-focal gas permeable lenses design. Recommended for patients who need to see at a distance, intermediate and near. Progressive vision is achieved through the use of an aspheric base and front. The 3E/EE-FOCUS lens unique design provides an optimal fitting relationship between the lens and the cornea, giving patients comfort without prism, intermediate blur and annoying segment search. For ADDs of +0.50D to +3.00D.
Many of contact lens wearers are reaching certain age to depend on reading glasses for near vision. Most of them do not want to give up contact lens wear if they have choice or with the help of 3E/EE-FOCUS Lens.
The 3E/EE-FOCUS is an easy to fit, comfortable lens. Most of the gas permeable lens wearer do not need adaptation period. Even new wearers adapt in a very short time. ADD power is available in all positions of gaze (no transition zone on the lens). The wearer will love the advantage of intermediate ADD powers. Yet, another advantage of this design is there tends to be little corneal steepening and it will correct corneal astigmatism for up to 2.00D.
Aspheric curves are used to generate the optics necessary for the multi-focal effect. Potential ADD ranges are from +1.00 to +3.00 D, depending on the base and front eccentricity and lens radius. Our proprietary edge configuration makes this lens different from other aspheric multi-focal on the market.
Pupil Size (normal room illumination)
Pupil size is an easily overlooked factor when assessing the 3E/EE-FOCUS lenses. Any extreme can cause a problem. Large pupils (greater than 5.5mm) may cause ghost image with any aspheric design. Very small pupils may impair near acuity, because the peripheral optics are not available through the small pupil.
Lid Position and Tension
The lower lid at the lower limbus is Ideal eye for 3E/EE-FOCUS lens. If the lower lid is too low, fit the 3E/EE-FOCUS lens either as a lid attachment or intrapalpebral fit. A high upper lid is best for an aspheric design as well as regular GP lens. This will allow you to adjust the design to aid centration. If the upper lid is above the superior limbus, you must fit the 3E/EE-FOCUS lens as an intrapalpebral lens. You may ask for the proper lens diameter. A very tight upper lid will also pose problems. When the lens cannot easily slide beneath the upper lid, it will be forced down. This will create centration problems with 3E/EE-FOCUS lens as well as regular GP lenses.
All dry eye and potential dry eye problems must be addressed prior to any contact lens therapy. If the patient is not willing to do the things necessary to improve and maintain their corneal health, they may not be an ideal candidate for contact lenses.
The patient’s psychological make-up will play an integral role in his/her success as a contact lens wearer. The patient who exhibits a negative attitude seldom succeeds. Remember, whether you believe you will succeed or fail, you will be right. As the eye care professional caring for your patients, you must exude confidence. Your patients will sense this and they will become confident too.
Counsel your patients to avoid having unrealistic expectations. If their minimum goal to be happy is to have perfect vision near and far under all lighting conditions, they will most likely be disappointed. To have a high probability of success, the patient must be highly motivated. If they just want to try bifocal contact lenses, you need to have a heart-to-heart talk with them so they understand their role in the success of this therapy. Some careers make bifocal contact lenses a less than ideal option as the primary vision correction. The computer users who require good near acuity for extended periods of time may not be an ideal candidate. The same may be true of the long distance truck drivers who demand for perfect distance vision. This could be a problem while driving at night, especially for the person with large pupils.People with high presbyopia may be disappointed with all the Multifocal design. They may experience a slight reduction in distance acuity while improving the near vision.Against-the-rule corneal astigmatism frequently causes problems with lateral decentration of any firm contact lens. Since centration is so important with bifocal lenses, approach these patients cautiously. Carefully evaluate corneal topography. If the toricity is limited to the central 3 to 4 mm, the lens may center well because the peripheral cornea is nearly spherical.
Motivation may be the most difficult factor to measure; yet it may be the greatest key to success for any firm GP lens wearer. Patients who are current GP lens wearers will have an advantage over the new wearer in that they will not have to go through an adaptation period. Patients who have never worn any correction may be among the most difficult to fit. Do not eliminate these people as candidates if they appear to be sufficiently motivated. Patients with perfect distance acuity will generally not be good candidates. If unaided distance acuity is good, they may not accept even a slight reduction in distance VA, even if their near acuity is fantastic.
DIAGNOSTIC FITTING 3E/EE-FOCUS LENS
After a thorough evaluation of the ocular health and refractive status of the patient, it is time to perform a diagnostic fitting. Select the lens from the standard diagnostic set that is 2.50 D steeper than the central flattest K. Allow the lens to settle on the eye for 10 to 15 minutes before instilling fluorescein onto the eye and evaluate the fit, movement and centration. The desired position is centered with 1-2 mm of movement on each blink. If the lens tends to ride high or move excessively you will need to order the lens with the steep mid-peripheral curves. If the lens centers low and/or does not move, you should order the flat mid-peripheral curves. To modify the fitting characteristics, choose a lens 0.50D steeper or flatter (as needed) and assess centration and movement. When ordering, request the appropriate base curve with either the steeper or flatter mid-peripheral curves. Over refract for best distance acuity and evaluate the near acuity through a trial frame. Record all the information and order the lenses.
The potential ADD powers of the diagnostic lenses will vary from 1.00 to 2.00D depending upon the base curve radius. The flatter the base curve, the lower the ADD. A front eccentricity curve may request If more than 2.00D ADD is needed. If you have the lenses made from material of lower refraction index, the lens will have a lower potential ADD. Please call our contact lens designer for further information.
SELECTING THE PROPER BASE ECCENTRICITY:
The potential ADD for a given eccentricity will vary significantly with the base curve. Use the chart below to determine the eccentricity necessary to achieve the desired ADD effect for your chosen base curve.