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C CLINICAL RESEARCH

STAGING GLAUCOMATOUS DAMAGE

A diagnosis of glaucoma cannot be made without a careful consideration of the classification of the severity of
disease, which requires careful assessment and documentation of structural and functional damage. There are
many different glaucoma staging resources to refer to. The commonality between them is their consideration
of the degree of structural and functional damage, and the ultimate risk of losing functional vision. 3,291,292 Con-
sideration must be given to the extent of optic nerve and RNFL damage and visual field loss (including mean
deviation and proximity of the field defect to fixation) when determining the level of glaucomatous damage
present. 96,157,292 Table 6 is an adaptation of the staging used in the Hodapp Anderson and Parish classification,
the Canadian Ophthalmological Society, and the Glaucoma Handbook written by optometrist, Dr. Anthony
Litwak. 157,291 Staging of glaucoma is critical because it will help in formulating a management plan and guide
management decisions including establishing a target IOP and frequency of follow-up. A standardized staging
system also facilitates shared management or transfer of care with a common and more objective understand-
ing of severity.

Table 6: Recommendation for staging of degree of glaucomatous damage. 96,157,291

Stage Visual Field Changes Optic Nerve And RNFL Damage
• MD < -5dB AND
• < 18 points below 5% • Thinning of superior and/or inferior rim
Early/Mild
• < 10 points below 1% on PSD e.g. C/D < 0.65 in an average sized nerve)
• No central points < 20 dB • No wedge defects
• -5dB < MD < -10dB OR • Early notch in superior OR inferior OR relative
• 18-36 points below 5% OR thinning in both superior or inferior rim
Moderate
• 10-20 below 1% on PSD OR (e.g. C/D 0.7 – 0.85 in an average sized nerve)
• Central points between 10-20 dB in one hemifield • Prominent wedge superior or inferior
• MD > -10dB OR
• > 36 points below 5% OR • Early notch of superior and inferior or complete
Advanced • > 20 points below 1% on PSD OR notch (eg C/D > 0.9 in an average sized nerve)
• < 20 dB in both hemifields centrally OR • Complete Wedge
• Any point in central 5 degrees < 10dB

Clinical Recommendation for staging glaucoma:
• Careful assessment of structural damage and functional loss allows staging of disease severity, which
subsequently informs all treatment and follow-up decision-making.

PROGRESSION ANALYSIS IN GLAUCOMA
As a rule, all patients with glaucoma will progress if followed long enough and with sensitive enough follow-
up techniques. An important consideration for each individual patient is whether the progression is occurring
at a rate that puts visual function and quality of life at risk. In some, progression occurs so slowly that visual
function will never be affected, while in others progression can be very rapid, leading to significant vision loss
despite medical and/or surgical intervention. The majority of patients fall between these two extremes. The
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goal of management is to provide intervention that is adequate enough to slow progression to a rate at which
vision will not become compromised in the patient’s lifetime, while at the same time not causing intolerable
side effects from treatment. 15,17,61

42 CANADIAN JOURNAL of OPTOMETRY | REVUE CANADIENNE D’OPTOMÉTRIE VOL. 79 SUPPLEMENT 1, 2017