

The perfect lens for presbyopia
I
recently attended an ABO- approved seminar that taught me a lot about
Progressive Lenses Vs. Flat Top Bifocals.
(below is some of what I learned)
Things have changed a lot since Ben Franklin invented bifocals in the late 1700's. Ben took two round lenses (one higher plus power) and cut them in half, placing the higher plus lens on the bottom half of the circular frame. By the 1800's the two glass lenses were being fused together with high heat for safety. Fused bifocals also the use of frame shapes other than round. Before bifocals a person had to have two pairs of glasses or give up reading. Trifocals were the next step toward giving a person back their natural vision. Lined bifocals are ancient in design compared to the Progressive lens designs available to eye care professionals. Today's progressive lens can be custom tailored to meet your patient's needs far greater than any lined bifocal.
Some quick facts
1. 150
million people in the US alone wear eyeglasses.
2.
Now about 50 % of all 70 million prebyopes are now in progressive Lenses.
3.
Flat top bifocals have a 6 % higher chance of non-adapt than a progressive lens.
4. Flat
top segments are more age revealing than less noticeable modern progressives.
5. Lined
bifocals create a scotoma (blind area in the visual field).
6.
A flat top trifocal creates two separate scotomas per lens.
7.
Progressives were first conceived in 1907 by the late Owen Aves.
(Owen Aves was one of the
"grand old men" of optics in the early part of this century. He was
instrumental in the development of optical education, and was a co-founder
of The London Refraction Hospital now known as "The Institute of Optometry".)
I have noticed that most opticians find a lens that seems to work well most
of the time and recommend that same lens for ALL patients regardless of the
patient's lifestyle. Today's opticians can custom tailor a progressive lens
style to match a patient's lifestyle. Some progressives are wider in the reading
area. Some progressives offer better peripheral in the distance. Some
progressives have a long channel, others are short. Some progressives are better
with low seg height frames and other are better for higher seg height frames.
Some progressives are better for computer use than others. Knowing which design
works best for your patient means you need to know which style is best for a
given scenario. Today's progressives offer opticians more profit than a flat top
while giving patients what they came to you in the first place for-----BETTER
VISION!
Stay
tuned for a progressive lens selection guide that will teach you which lens
brands and styles work best for your patients needs.