The “C” procedure was developed by Canrobert Olivera of Brazil. The procedure consists
of 6 incisions as shown in figure A and figure B. The pattern was developed after
Dr Olivera observed the pattern shown in figure C after performing relaxing incisions.
He observed sufficient relaxing to control astigmatism in the central cornea but
“leaking” of the astigmatic pattern around the incisions in the midperiphery resulting
in an “X” astigmatic pattern which he dubbed keratopyramis. Persitant keratopyramis
can be a disturbing visual problem with diminished best corrected astigmatism and
side effects such as glare. His solution was to make a set of 4 additional incisions
outside the 2 primary incisions to prevent “bleeding” around the primary incisions.
The procedure which resulted was successful in preventing keratopyramis but also
has other admirable properties. In the nomogram provided below we note that no single
incision is longer than 60 degrees. These relatively short incisons heal well and
result in a stable correction after healing.
Markers for this operation are available from Mastel Precision.