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. 

• Dr. Szczotka is seeing more cases of permanent corneal warpage from long term wear of PMMA which can mimic keratoconus.
   
• Pellucid's patient's lenses usually ride low. It can be difficult to differentiate the two conditions without topography. Thinning is usually inferior with Pellucid's. Pellucid's patients can generally be refracted well, with lots of against-the-rule cylinder.
   
• Dr. Szczotka recommends a low Dk material for keratoconus.
   
• New research presented at ARVO shows that KC tissue has a deficiency of protease inhibitors so overactive tissue destruction and thinning occur, this has not been documented in normal corneas.
   
• The best starting lens is one that just clears the apex of the cone. Apical clearance is preferred to 3-point touch. Use the axial maps to find the apex of the cone and start from there. If the lens rides too low go flat and try for lid-attachment.
   
• If a GP simply won't work (and you've exhausted all options) a soft toric will often work. The biggest problem with soft torics is their unpredictable powers when on the eye; you may go through 1/2 dozen lenses and bizarre over-refractions until they work in KC.
   
• EyeSys gives better maps than many topographers on advanced cases because the placido rings are wider. This group had no experience with Euclid.
    
• Optical zone is usually 1.5-2.0 mm less than the OAD, if tight in the periphery can go a little smaller.
   
• Patients like the ease of use with liquid enzymes, but samples are hard to come by.
   
• Discussion of replacement times on high Dk lenses-- some docs shy away from high Dk because they feel it doesn't give good value. Others cited cases were high Dk materials lasted as long as 18 months.
   
• Much time was devoted to discussion of specific keratoconus cases that attendees were in the process of fitting.

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