I am new to the OptiBoard and would like to seek any suggestions on the following case:
The patient had RK about 20 years ago and was left with irregular astigmatism, poor contrast sensitivity and for now asymptomatic meridional anesiokonia. On top of this, he also had muscle surgery 12 years ago for a long standing forth nerve palsy and now is beginning to show a vertical imbalance again. He has worn Varilux Comfort lenses for about 10 years and has tolerated progressive lenses better than one might have thought. His last Rx was OD +1.12 -1.50 x 148, OS +3.50 -2.00 x 082, with +2.50 add OU in the 1.67 index material with +5.50 BC OU.
My five-fold goal for this patient is to design new progressive lenses that will enhance contrast sensitivity, not push him over the edge on the anesiokonia, to correct his vertical imbalance, maintain comfortable vision at near, with glasses that are cosmetically pleasing.
RX: OD +1.25 -1.50 x 130 with 2 prism diopters base up, OS +4.00 -2.25 x 087, +250 Add OU. Monocular PD is OD 33.5, OS 34.5.
Goal #1: Enhance overall vision and contrast sensitivity by switching to an uncoated Autograph II variable (free-form), 1.60 Index, and applying Zeiss Carat Advantage AR with Foundation A.
Goal#2: Try to maintain or slightly improve the current meridional anesiokonia in the vertical meridian by using equal BC OU (either +5.00 or +6.00), minimum center thickness on the OS and matching it on the OD. Vertex distance is probably stuck at 13mm because of deep set eyes. I am not sure what BCs the manufacture recommends, but I suspect it is probably a +6 on the OD and +7 on the OS which would only make the anesiokonia worse.
Goal#3: Fully correct the vertical phoria with 2 prism diopters base up on the OD (not split). Normally, I would cut the prism, but I am leaning on giving it all because not correcting it would only increase the induced vertical prism in the reading portion of the lens.
Goal#4: Although I measured 20 high to center of pupil on each eye, I plan to set the OD at 19.5mm and the OS at 20mm to account for image displacement secondary to the vertical correction. The one thing I have considered, but not sure I want to do is to slab-off the OD. It is my understanding that on a free-form lens they can nearly make the line invisible by blending it. I am just not sure it is needed since I am adding back the vertical correction. I guess the other thing I could consider is using a shorter fixed corridor length, but since his former lens is such a soft design, I’m not sure that is a good idea. I would really like to hear some input on the slab-off and between variable and fixed corridor length.
Goal#5: I guess in addition to the above, the frame choice would be the only other key decision. The Frame being considered is a Charmant AR6020 (Eye 53, DBL 19, B 38, ED 57), Pantoscopic Tilt is 10 degrees, Panoramic Angle is 5 degrees, and as stated Vertex distance of 13mm. The only difference from his current frame is that the B is 34 and the ED is 54 in his old glasses.
I would love to hear any suggestions or recommendations.
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