Globally, the number one consideration in contact lens patient management is safety. And orthokeratology seems to get a fair share of the attention when it comes to that. At the recent BCLA meeting in Manchester (UK), Mark Bullimore discussed published and ongoing studies and proposed that the risk of infection with overnight orthokeratology may be similar to any other overnight lens wear modality. Helen Swarbrick presented a poster at ARVO showing no difference in epithelial desquamation rate and bacterial binding between overnight wear of normal (R)GP lenses and orthokeratology (ARVO poster #5624). Jennifer Choo found in her PhD studies that despite the changes in the corneal tissue with this procedure, the corneal defenses are still intact and these changes did not predispose the eye to infection. In a free accessible paper in the Februari issue of Optometry & Vision Science it was stated that there were no significant differences in the number of bacteria adherent to normal (R)GP lenses and orthokeratology lenses. But orthokeratology lenses did retain higher numbers of viable bacteria, and extra attention for cleaning seems advised. 

 

Contact lens fits on post refractive surgery corneas are becoming more and more routine now - not only due to surgical failures, but also because of corneal changes over time and emerging Presbyopia. (R)GP lenses are widely used for this purpose with great success. The patient we would like to present has an abnormally thin cornea and high visual demands for business purposes.

See this month's case report for full coverage of this back toric large diameter lens fit. 

 

 

Not the eye of a lizard, but the flattest available large diameter back toric (R)GP lens on a (human) cornea plana, a rare anomaly showing a very flat corneal topography. An air bubble is trapped underneath the lens. This patient is refitted with a high plus (+6.00D) silicone hydrogel lens with a normal (R)GP lens on top (piggy back).

Photo: Hans Kloes (the Netherlands)