patient complain Reading area not the same.

[Win C]

recently fitted a patient (1st time wearer) with a pair of seiko back surface progressive (P-1sy).

RX

R +0.50
L pl /-0.75x180
Add +2.25

Fitting ht is R 20 L 19

He complained that the peripheral vision on the left for reading is not as wide as that of the right side., ie he can read more to the right than to the left.

There is no problem with distance.

So what could be the problem? I have checked the refraction and PD, everything seems right.

1) could the cyl on the left cause the problem?
2) could it be due to the fitting height? the left fitting ht is lower, causing the restricted FOV.

Which is more likely cause?

[Raanan Bavli]

1) could the cyl on the left cause the problem?
2) could it be due to the fitting height? the left fitting ht is lower, causing the restricted FOV.

Which is more likely cause?

Wouldn't it be nice if they gave you power an cyl maps along with these lenses?

[MarcE]

1) could the cyl on the left cause the problem?
2) could it be due to the fitting height? the left fitting ht is lower, causing the restricted FOV.

yes, both.

[eryn]

I would try to match the segs. Make it a 20mm seg OU and see if that corrects the problem.

[mahmoud.hamza]

check if the frame have the same distance between the 2 eyes?
also I did not really appreciate that the fitting hight is different !!

[SailorEd]

Does the patient have ambliopia? Check to see if his eyes converge the same when looking down. Make sure the frame is centered on the bridge and not to one side or the other. All things being equal, are one of the lenses tipped a bit? Some people have trouble with a lens being "just a little" off.

[Refractingoptician.com]

recently fitted a patient (1st time wearer) with a pair of seiko back surface progressive (P-1sy).

RX

R +0.50
L pl /-0.75x180
Add +2.25

Fitting ht is R 20 L 19

He complained that the peripheral vision on the left for reading is not as wide as that of the right side., ie he can read more to the right than to the left.

There is no problem with distance.

So what could be the problem? I have checked the refraction and PD, everything seems right.

1) could the cyl on the left cause the problem?
2) could it be due to the fitting height? the left fitting ht is lower, causing the restricted FOV.

Which is more likely cause?

(1) Peripheral vision is more likely a horiozontal component , therefore what are the mononocular PDs ?
(2) Put the original Seiko dots back on the lenses and recheck the horizontal & vertical fittings . Do they match the patient pds ? How did you measure the patient PDS ?
(3) If there is a big difference in monocular pds as compared to frame shape , it is possibble that there will not be the same peripheral viewing area due to the off center lens position and frame shape.
(4) Check his old glasses to see how they were centered . Does he experience the same with his old ones ? Why not ?
(5) Remove the new left lens from the frame . Have him wear the new frame while holding the new left lens up against the eyewire rim and you move the lens horizontally ,slowly, until you find a postion where he is happy . Recut the left lens to this position .
(6) If you can't find a "happy" position do this :
Remount the lenses to the frame .
Cover the patient left eye and determine the amount of width in the right eye then cover the right eye and see how much there is in the left . Does this agree with the amount of vision he is complaining of with both eyes uncovered ? If the area of poor peripheral is to the nasal side, is it possible that his nose/eye anatomy is blocking that viewing angle ?

A person with say a 33/28 monocular PD has their left eye closer to their nose than the right eye therefore their left eye viewing area is naturally obstructed by the nose when looking to the right with their left eye .

Is there a hemisphere that is not available or functioning?

[EyeFitWell]

Do you mean both lenses have more distortion on the left vs right sides of the corridor? Or are you saying the left lens has more distortion than the right?