Greetings!
Ray Sievert is back in today's session of iTrace U with a
video
asking some provocative questions about why the industry is using 6mm for evaluating corneal spherical aberrations as well as higher order aberrations. We WANT YOUR
FEEDBACK
!! Please hit the feedback button on the bottom of this communication for a direct email to Ray with your thoughts on this series and what you would like to see.
THINGS TO LOOK FOR IN THIS TEACHING:
The 6mm size is considered a standard for reviewing the Corneal Spherical Aberration as well as the cornea’s HOA’s. Our common-sense view is that the pupil size is more relevant than just a standard measure. The pupil size that works for young lasik eyes is not the same as the pupil size for the cataract aged patient. Spherical aberration amounts increase dramatically in many eyes between 5 and 6 millimeters, but the pupil size can be much smaller in most cataract patients, so does this 6 mm area really affect their vision?
THINGS TO CONSIDER WHILE YOU ARE WATCHING:
Many of you implant IOLs and use Aspheric Lens matching by using 6mm of corneal area to decide how much spherical aberration you want to neutralize. Is this relevant to all of your patients or do the patients with much smaller pupils get little to no effect from these lenses? "What’s the difference?" you might say. But recall that an aspheric lens that tilts can cause much more aberrations than a standard spherical lens.
THINGS TO CONSIDER STUDYING IN YOUR PRACTICE:
Study your patients with varying degrees of spherical aberration at 6mm regardless of their pupil size. Do all those with high SA have similar complaints about night myopia or glare/halo or do those complaints follow their scotopic pupil size? The larger scotopic pupil sizes will have more complaints if this argument is valid. Let us know what you find.
Look for our next iTrace U email in your inbox soon, but if you want more now you can always visit our
online library
.
