canadian ophthalmological society

Canadian Ophthalmological Society

Evidence-based Clinical Practice Guidelines for the Management of

Glaucoma in the Adult Eye

Progression

Definition of progression

• A patient’s glaucoma is deemed to have progressed if structural and (or) functional changes, associated with the disease, are verifiably detected on clinical examination and (or) testing.

• The clinical significance of this progression, and the actions taken, will be influenced by:– the extent of damage prior to the change, and– the threat of visual handicap if further progression

were to occur.Canadian Ophthalmological Society evidence-based clinical practice guidelines for the management of glaucoma in the

adult eye. Can J Ophthalmol 2009;44(Suppl 1):S1S93.

Methods of detecting progression

• Progression may be detected, clinically or with the aid of various technological investigations, as loss of tissue (structural) and/or vision (function).

• Careful ophthalmoscopy and precise documentation (i.e., photography or imaging) may confirm loss of RNFL or optic disc tissue over time.

Canadian Ophthalmological Society evidence-based clinical practice guidelines for the management of glaucoma in the


Methods of detectingprogression (cont’d)

• Confirming progressive vision loss requires threshold evaluation of the peripheral field.

• In both instances, the potential for greater sensitivity and quantification of change mayexist for technologically based evaluations compared with clinical examinations alone.



Endpoints for conversion to, or progression of, glaucoma in major RCTs

Study Event measured Endpoints for eventmeasured in both

arms of study

Total endpoints,

%

OHTS Conversion to OAGODPVFP

ODP and VFP

553510

EGPS Conversion to OAGODPVFP

4060

CNTGS Progression of OAGODPVFP

1189

EMGTS Progression of OAGODPVFP

ODP and VFP

18613



Progression — technology choices

RecommendationAssessing disease severity is important to determine which tests might be most useful for each individual. Patients with glaucoma should be monitored with both structural and functional tests, as progression can be detected by either method alone [Level 21].

1. Artes PH, et al. Prog Retin Eye Res2005;24:333–54.



VF progression endpoints forthe major glaucoma RCTs

RCT VF endpoint

CNTGS • Deepening and (or) expansion of existing scotomas and (or) new scotomas confirmed on 2 of 3, or 4 of 5 follow-up VFs

AGIS • Increase in VF score of 4 units on a scale of 0–20 from2 baseline Humphrey 24-2 full-threshold VFs

CIGTS • Increase in VF score of 3 units on a scale of 0–20 (slightly different from that used in AGIS) from baseline

EMGTS • Three adjacent points showing significant progression according to the Humphrey Glaucoma Change Probability assessment

CGS • Four of 8 points showed significant progression according to the Humphrey Glaucoma Change Probability assessment on 2 of 3 VFs



Advantages and disadvantages ofevent-based and trend-basedapproaches to VF progression

Type of progression analysis

Advantages Disadvantages

Event analysis • Earlier detection of change

• Fewer tests required

• Intertest variability may result in change reverting to baseline

• No rate of change calculation possible

Trend analysis • Rate of change (and prognosis) possible

• Allows clinician to tailor aggressiveness of therapy

• More robust in the face of intertest variability

• More tests and longer follow-up required

• Insensitive to minor changes at specific loci in the VF



Progression — correlationbetween structure and function

RecommendationIt is recommended that a correlation between structural and functional changes be sought in suspected progression, even though it is more common for a change to be detected with one or the other independently [Level 11-4].

1. Collaborative Normal-Tension Glaucoma Study Group.Am J Ophthalmol 1998;126:487–97.2. Kass MA, et al. Arch Ophthalmol 2002;120:701–13.3. Heijl A, et al. Arch Ophthalmol 2002;120:1268–79.4. Miglior S, et al Ophthalmology 2002;109:1612–21.



Risk factors and their relationshipto VF progression examined

in the landmark RCTs

Characteristic CNTGS CIGTS EMGTS AGIS CGS

Age No Yes Yes Yes Yes

Baseline IOP No NR Yes NR No

Severity of VF damage*

No Yes Yes Yes, but opposite direction

from other trials

No

IOP overfollow-up

Yes No Yes Yes Yes

Intervisit IOP fluctuation

NR NR No Yes† No

*Positively associated if more severe baseline VF damage resulted in greater degree of VF progression†Positive association in patients with low mean IOPs and not high mean IOPs



Risk factors and their relationshipto VF progression examined

in the landmark RCTs

Characteristic CNTGS CIGTS EMGTS AGIS CGS

Disc hemorrhage Yes NR Yes NR NR

Migraine Yes NR NR NR No

Race Non-Asian

Non-white NR No NR

Gender Female No No Male‡ Female

Pseudoexfoliation NR NR Yes NR No

Diabetes No Yes No Yes No

Anticardiolipin antibody

NR NR NR NR Yes

‡Positive association in ATT and not TAT sequence



Progression significant forthe patient

• The significance of a detectable structural and (or) functional change would be different for different patients.

• The ophthalmologist’s response should reflect the significance to the patient.



Progression significant forthe patient (cont’d)

• Significance and action taken would be influenced by some of the following considerations:– What is the baseline level of glaucomatous damage (i.e., is the

VF full with a nearly normal-appearing disc, or is fixation threatened in 3 of 4 quadrants)?

– What is the status of the fellow eye?– What is the health of the patient and life expectancy?– What are the visual demands of the patient (e.g., is he or she

still driving)?– What is the next step? Is it heightened surveillance or is it

incisional surgery?– What is the patient’s interpretation of the change and the

proposed actions?Canadian Ophthalmological Society evidence-based clinical practice guidelines for the management of glaucoma in the


Visual field — progression confirmation

RecommendationThe clinician’s response to a new progressive event should be to confirm the change with a repeat test. VFs may need to be performed more frequently during periods of apparent progression. Ultimately, it is most important to calculate the rate of progression over time [Consensus].



Number of annual VF tests neededto detect total mean deviationchange over 2, 3, and 5 years

Total mean deviation change, dB

2 years 3 years 5 years

– 1.0 7 6 4

– 2.0 5 4 3

– 4.0 3 3 2

Adapted from: Chauhan BC, et al. Br J Ophthalmol 2008;92:569–73.



Visual field — baseline

RecommendationIn order to establish a good baseline and to detect possible rapid progression, several VFs should be performed at regular intervals in the first 2 years [Consensus].



Frequency of follow-up

• Frequency of follow-up is influenced by a number of factors.

• Patients with stable glaucoma, or ocular hypertension who are on treatment, need assessment at least once a year.

• Depending on disease severity, other patients will require more frequent assessments.

• Clinical judgment and common sense should be exercised when dealing with very elderly patients who travel long distances for follow-up, particularly duringthe winter.



Recommended clinical assessment*

intervals for stable† chronic glaucomas

Stage Interval

Glaucoma suspects 12 years

Early glaucoma At least every 12 months

Moderate glaucoma At least every 6 months

Advanced glaucoma‡ At least every 4 months

*Assessments might include any of the components listed in Table 2 in addition to documentation of the optic disc and VF testing.†More frequent evaluations may be necessary if indications listed in Table 17 are noted.‡It may be necessary to see patients with advanced glaucoma very frequently (weeks or days) if their IOP is poorly controlled, progression appears rapid or fixation is threatened.



Indications for more frequent follow-upor heightened surveillance

On the basis of the history On the basis of the exam

Suspect adherence Side effect to glaucoma medication

Systemic drug change (new corticosteroids or antihypertensives)

Intervening eye infection (especially for postoperative eyes), trauma, surgery or iritis

Change in health status IOP above target

Change in health insurance(i.e., access to medications)

Disc change

Change in social history(i.e., availability of caregivers)

VF change



Progression: Treatment goals

• Some degree of progression may be unavoidable in glaucoma.

• Goals for the clinician include:– measuring and minimizing the progression,– preserving or enhancing QOL, and– choosing a management scheme that is

appropriate and acceptable to the patient.



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