Scleral lenses are large diameter rigid oxygen permeable lenses. They only touch the outer, white part of the eye (sclera). Because they rest on the sclera and don't touch the cornea they are very comfortable, even for new wearers.
These large lenses are most often used for corneal dystrophies like keratoconus, but can also be used for patients with severe dry eye, since they trap unpreserved saline solution against the eye for the entire wearing period.
Dr.Lutz is very experienced in fitting these lenses, and has given two lectures at national eye care meetings on the subject. Dr. Lutz has keratoconus personally, and wears scleral lenses himself. This gives him a better perspective on the intricacies of fitting these lenses.