Ralph developed a numerical classification for chemical burns of the eye which graded the severity based on clinical findings.
The original classification scheme was ranked by severity points (0 normal, 4 severe injury):
Clinical Finding |
Points |
perilimbal hyperemia |
0 |
chemosis |
1 |
spotty perilimbal ischemia |
1 |
clouded epithelium |
1 |
spotty denudation of epithelium |
1 |
up to 50% epithelial loss |
2 |
mild stromal haze, iris details visible |
2 |
vertically oval, fixed pupil |
2 |
iridocyclitis |
2 |
perilimbal ischemia less than one third circumference |
2 |
complete epithelial loss |
3 |
moderate stromal haze, iris details barely visible |
3 |
perilimbal ischemia one third to one half of circumference |
3 |
sustained increase of intraocular pressure during first 24 hours |
3 |
severe stromal haze of opacity, no iris details visible |
4 |
perilimbal ischemia greater than one half the circumference |
4 |
Rearranging this by clinical parameter, with the most severe finding scored:
Parameter |
Finding |
Points |
perilimbal change |
hyperemia |
0 |
|
spotty ischemia |
1 |
|
ischemia less than one third of circumference |
2 |
|
ischemia from one third to one half of circumference |
3 |
|
ischemia greater than one half of circumference |
4 |
epithelium |
no change |
0 |
|
clouded |
1 |
|
up to 50% loss |
2 |
|
complete epithelial loss |
3 |
stromal haze in cornea |
none |
0 |
|
mild, with iris details visible |
2 |
|
moderate, with iris details barely visible |
3 |
|
severe and opaque, with no iris details visible |
4 |
chemosis |
none |
0 |
|
present |
1 |
pupil |
no change |
0 |
|
vertically oval, fixed pupil |
2 |
iridocyclitis |
absent |
0 |
|
present |
2 |
intraocular pressure |
normal |
0 |
|
transient increase |
0 |
|
sustained increase during first 24 hours |
3 |
score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 0
• maximum score: 19
• The higher the score, the greater the damage.
Score |
Injury |
Interpretation |
0 – 3 |
insignificant |
Rapid recovery without sequelae. |
4 – 6 |
mild |
Rapid replacement of damaged epithelium with clearing of any stromal haze. Return of visual acuity to the baseline usually occurs within 1-2 weeks. |
7 – 9 |
moderate |
Usually with a delay of 1-3 weeks in complete re-epithelialization. Some reduction in visual acuity may result from persistent haze of the stroma. A mild pannus stabilizing at 1-2 mm onto the cornea is common. |
10 – 12 |
severe |
Sluggish regrowth of epithelium and frequent development of pannus. A furrow from collagenolytic activity in advance of the pannus is common. Perforation is a definite possibility. Evan at best, the final visual acuity will remain low because of pannus and a lingering stromal haze. |
>= 13 |
very severe |
These are the worst burns initially and those with the poorest long term prognosis. The early inflammatory response subsides only after several months. A dense pannus develops, especially from above. Invariably there is active collagenolysis, often with perforation. A cataract is expected. After many months or years the most fortunate patients end up with dense corneal scarring and vascularization, along with frequent secondary glaucoma. |
Specialty: Toxicology, Emergency Medicine, Critical Care, Ophthalmology
ICD-10: ,