Zeiss SV & Progressive fittings

[Hollybabette]

Hey everyone,

Our office has been having a recent issue of fitting the Zeiss SV Individual on OC. Patients seem to be lifting their chin to see clearly. I spoke with Joe, The lab manager at Zeiss - Montclair, regarding this issue. He told me many accounts are adding 4 mm to the OC height, due to the SV lens having a 4 mm drop. So, ultimately raising the OC ht by 4 mm would solve the issue. But, why should I have to "fudge" the OC ht at all? Other manufacturer's like Hoya are OC, without any drop.

Also, anyone having trouble with the Zeiss Individual 2 progressive and the popular P3 lens shapes with 40mm B Box as example? The variable corridor is too long and the patients cannot reach the add power fast enough without lifting the frame or tilting their heads back, when marked at pupil center. The lab manager at Zeiss said his solution would be to raise the seg ht by 2 mm to bring the add power up for faster acceleration.
I would never raise a seg ht on a progressive. I would prefer to use a fixed progressive design and control exactly where the add power is located and specify my corridor length.

**He said he does not recommend any of these fitting changes, but he had his accounts having problems with both of these lenses and that is how they have solved the issue.

As of right now, I have no confidence in Zeiss's lenses and fitting procedures. So, what do you guys think? Help?

[Lelarep]

In the fitting guide for the SV individual, it mentions the 4mm difference.

[Paul Smith LDO]

No issues with the I 2, are you providing your lab with POW measurements and are you pre adjusting/fitting the frame prior to taking POW measurements.

[Hollybabette]

In the fitting guide for the SV individual, it mentions the 4mm difference.

Yes. I do understand the four millimeter difference, but I want to know why there is a 4 millimeter drop in the first place. On the fitting chart it says to read the prison reference and the power at the 180 line. Do I have to raise my optical center height for millimeters to get the correct prescription? With other single Vision digital lenses I don't have to do anything to the optical center height.

[Hollybabette]

No issues with the I 2, are you providing your lab with POW measurements and are you pre adjusting/fitting the frame prior to taking POW measurements.

Yes we are providing the pow measurements, and preadjusting. But I've noticed many of our patients don't like the long corridor. It seems they have better luck with short Corridor Progressives. And with the individual 2 Progressive, if there is a long vertical measurement of the frame itself, it will provide a long corridor

[Paul Smith LDO]

Yes. I do understand the four millimeter difference, but I want to know why there is a 4 millimeter drop in the first place. On the fitting chart it says to read the prison reference and the power at the 180 line. Do I have to raise my optical center height for millimeters to get the correct prescription? With other single Vision digital lenses I don't have to do anything to the optical center height.

Default mechanism, most providers don't provide POW measurements with FFSV and the 4 mm drop takes Martin's Formula for tilt into account. Have a talk with your lens rep and the lab and ask what they want from you. If there is some issue with the fitting height, draw a horizontal line intersecting the two CP marks to make sure the CP height is correct. The key is continuity between the staff, your customers and the lab. Some frames may not be suitable for your patients, their Rx, and their intended use. Interviews help determine customers objective and provide you with corrective measures.

[Robert Martellaro]

Hey everyone,

Our office has been having a recent issue of fitting the Zeiss SV Individual on OC. Patients seem to be lifting their chin to see clearly. I spoke with Joe, The lab manager at Zeiss - Montclair, regarding this issue. He told me many accounts are adding 4 mm to the OC height, due to the SV lens having a 4 mm drop. So, ultimately raising the OC ht by 4 mm would solve the issue. But, why should I have to "fudge" the OC ht at all? Other manufacturer's like Hoya are OC, without any drop.

The other designs might use prism thinning to achieve the same results, that is, a thinner better profiled lens. If your client is anisometropic though you probably won't use a Zeiss SVDO lens because of the drop.

Also, anyone having trouble with the Zeiss Individual 2 progressive and the popular P3 lens shapes with 40mm B Box as example? The variable corridor is too long and the patients cannot reach the add power fast enough without lifting the frame or tilting their heads back, when marked at pupil center. The lab manager at Zeiss said his solution would be to raise the seg ht by 2 mm to bring the add power up for faster acceleration.

Yes, for the older generations, especially for myopes, but not with what has been available in the last 2 years or so. Moreover, if you need a shorter corridor, order the 2N.

I would never raise a seg ht on a progressive. I would prefer to use a fixed progressive design and control exactly where the add power is located and specify my corridor length.

Bravo!

**He said he does not recommend any of these fitting changes, but he had his accounts having problems with both of these lenses and that is how they have solved the issue.

As of right now, I have no confidence in Zeiss's lenses and fitting procedures. So, what do you guys think? Help?

Not with the latest generations. I'm fitting and wearing Zeiss lenses. My only complaint is the lack of flatter base curves, especially with the polarized blanks, although that may have a fix coming up in the near future.

Hope this helps,

Robert Martellaro