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2/22/96 Chapter 7 Slit Lamp, Fundus, and Tonometry page 7-3
with loss of transparency in the central cornea. They are usually less dense than either
of the corneal light reflexes, overlie Vogt’s striae, and can be either singular or multiple.
The corneal scarring density grading scale is as follows:
Grade 1
Grade 1.5
Grade 2.0
Grade 2.5
Grade 3.0
Grade 3.5
Grade 4.0
Just noticeable
Easily noticeable
Dense
Opaque
The density of each scar is recorded on the CLEK Examination Form.
The host-graft interface of a corneal graft does not have to be documented as
corneal scarring. However, any other scarring in the donor button of the corneal graft
should be recorded on the CLEK Examination Form.
7.4 Corneal Staining
For the purposes of the CLEK Study, corneal staining is described during the slit
lamp examination based on its shape and its density.
In terms of shape:
• Arc staining is typically caused by the posterior lens surface junctions or lens
edge or deposits on the posterior surface.
• Punctate staining is synonymous with stipple staining.
• Foreign body staining is from debris behind the lens and is randomly located.
It could also be caused by a chipped, cracked or broken lens.
• Coalesced staining is the coalescence of punctate staining into a patch, eg,
coalesced staining from peripheral corneal staining, from “3 and 9 o’clock” staining, or
from deposits on the posterior lens surface or from a raised epithelial lesion.
• A full thickness defect is an absence of epithelium in an area, ie, it must show
stromal fluorescein absorption.
In terms of density of staining:
• Trace is just noticeable and requires no treatment.
• Mild is easily detected and requires no treatment.
• Moderate is easily visible and requires treatment.
• Severe involves pain and requires treatment.