Please note that the comments below are representative of remarks made in the chat room, and do not necessarily reflect the views of the moderators, the guest expert, or the GPLI.

• Topography is useful for determining back curves, but bogus on power. It will show whether the astigmatism is across most of the cornea or limited to the visual axis.
   
• Back torics can be used for fitting irregular corneas, but reverse geometry lenses are better.
   
• Dr. Bergenske feels that most irregular corneas can be fitted with spheres, but that the K readings are meaningless. You have to put a lens on the eye and observe the fl. pattern to determine fit.
   
• 2.5 D of corneal cyl should trigger the thought of torics, verified with observation of a spherical trial lens, although most of the group thought 2.00 D should be the point at which to fit toric vs. sphere.
   
• Flexure is minimized by going with a toric.
   
• Toric trial lenses make the fitting very simple and straight-forward. Those with toric trial sets made an effort to "sell" the rest of the group on them. They suggested 2 & 3 D sets for maximum benefit. Dr. Bergenske, however, stated that 99% can be fitting from spherical trial lenses and that toric trials are only useful if they are in the SPE design.
   
• To mark the flat axis of a toric lens just a sharpie pen to make dots at either lens edge while observing it on the lensometer. Then 'snap' and inked thread across the dots to make a solid line.
   
• Don't think about a bi-toric unless the acuity is making the patient unhappy-- use an SPE.
   
• According to Dr. B, empiric fitting of bitorics requires a pristine cornea, which he thinks is rare, some attendees disagreed.
   
• Discussion of reverse piggy-back for post-RK patient from last month (still not resolved) and new materials.
   
• "Material doesn't matter, the lab that finishes it does."

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