Surgery Outcomes By Arun C. Gulani, Md, Ms - OCULUS Pentacam Interpretation Manual

15 Using Pentacam ® technology to evaluate corneal
scars, planning and documenting surgery outcomes
15 Using Pentacam
corneal scars, planning and documenting
surgery outcomes
by Arun C. Gulani, MD, MS
I'd like to present the cornea as an elegant, optically powerful, and visually focused organ which is
readily accessible for shape modification aimed at achieving unaided vision. Unless there is a severe
and pervasive corneal pathology/perforation a penetrating corneal transplant should be in my opinion
the last resort of corneal rehabilitative techniques.
When looking at a corneal scar our inherent mindset is: "There is the culprit. Let's eradicate it".
What I suggest instead is to study the corneal scar and its impact on vision and the Pentacam®
technology, especially its corneal densitometry program is a dominant diagnostic in this direction. It
can essentially visualize the scar, its depth in the cornea; correlate it to corneal shape (topography)
and its consequent impact on refraction. In each and every patient with corneal scarring I begin my
quest by using the Pentacam® to determine the depth and density of the scar and its correlation with
topography. This helps me decide whether the scars are superficial (less dense) or whether they are
denser and deeper. For clinical ease, I have divided corneal scars into "on-cornea" scars
Figure 130), which are located above Bowman's membrane and lead to a camouflaged topography
and misleading refractive error, and "in-cornea" scars
part of the cornea, directly influencing its topography and hence its refractive error. This helps me to
decide which treatment method to choose.
Figure 129: Corneal Optical Densitometry display showing findings on an on-cornea scar
108
technology to evaluate
®
(Figure 131, Figure
(Figure 129,
132), which actually become