DIS - Glaucoma Management I - Week 7

Question 1

What number of signs is needed for a definitive diagnosis of glaucomatous optic neuropathy? List them.

Answer 1

3 signs:
ON (NNR) loss
RNFL (mGCC) loss
VF defects

Question 2

What is the likely diagnosis for a VF defect with no other cause? What about a VF defect in combination with either ON or RNFL loss?

Answer 2

Both likely open angle glaucoma

Question 3

What is the likely diagnosis for ON and RNFL loss but normal VF?

Answer 3

Likely pre-perimetric open angle glaucoma

Question 4

What is the first step in the treatment loop of glaucoma? Explain for open angle glaucoma and low tension glaucoma.

Answer 4

Setting a target IOP
OAG: -25% / 18mmHg
LTG: -30% / 12mmHg

Question 5

What is the most common intervention to reach target IOP for glaucoma?

Answer 5

gtt PGA noce

Question 6

What is the next step after prescribing a drug for glaucoma? What should be kept in mind?

Answer 6

Monitoring response to the Rx
-review in a month
Keep in mind the patient’s adherence to the Rx
-dont assume they will follow Rx instructions

Question 7

What time period after initiating glaucoma treatment should you refer to a specialist for surgical consult?

Answer 7

4/12

Question 8

What are the NHMRC first choice drugs for treating glaucoma? List four options, including drug name, brand name, and concentration.

Answer 8

Latanoprost (Xalatan) 0.005%
Travoprost (Travatan) 0.004%
Bimatoprost (Lumigan) 0.03%
Salfutan (Tafluprost) 0.0015%

Question 9

What are the NHMRC second choice drugs for treating glaucoma? List seven combination options, including drug name, brand name, and concentration.

Answer 9

Travaprost (0.004%) + Timolol (0.5%)
-DuoTrav
Latanoprost (0.005%) + Timolol (0.5%)
-Xalacom
Bimatoprost (0.03%) + Timolol (0.5%)
-Ganfort
Brimonidine (0.2%) + Timolol (0.5%)
-Combigan
Dorzolamide (2%) + Timolol (0.5%)
-Cosopt
Brinzolamide (1%) + Timolol (0.5%)
-Azagra
Brinzolamide (1%) + Brimonidine (0.2%)
-Simbrinza

Question 10

What drug combination is good for low tension glaucoma?

Answer 10

Brinzolamide (1%) + Brimonidine (0.2%)

-Simbrinza

Question 11

What is the NHMRC third drug of choice for glaucoma?

Answer 11

Pilocarpine (1%, 2%, 4%)

Question 12

According to the NHMRC, when is surgery recommended in glaucoma?

Answer 12

Only if drugs do not stabilise IOP to the target set

Question 13

What percentage of pateitns do not comply with drug use instructions after 1 month? What about after a year?

Answer 13

1 month - 20%

1 year - 65%

Question 14

What is a solution to people who cannot instil drops (2) due to physical/psychological limitations?

Answer 14

Drop aid or assistant

Question 15

What is a solution to people who have unacceptable side effects from eyedrops (2)?

Answer 15

Alter drug

Surgery referral

Question 16

Should you always treat glaucoma if the diagnosis is established?

Answer 16

Yes

Question 17

Are PGAs on their own generally adequate for glaucoma?

Answer 17

Yes, long term in 70% of cases

Question 18

Briefly summarise glaucom management by optometrists (5).

Answer 18

Establish diagnosis, initiate treatment
Obtain a baseline - VF/OCT/photo
Monitor 0/12, 1/12, 3/12, then 4/12 for 8 VF tests, then 6/12 or 12/12
Consider need for neuro-protection
Refer at 4/12 to specialist for surgical options

Question 19

Define target IOP. Does it change with age?

Answer 19

IOP that affords no loss of ganglion cells beyond ageing, for a particular patient

Question 20

What is the target IOP generally and where does this figure come from?

Answer 20

Can change with age
Initial target is -25%, derived from clinical trials
-can be adjusted
Typical target: -25% or 18mmHg, whichever is less

Question 21

What percentage of treated glaucoma cases progress in two years? what does this suggest of the Rx?

Answer 21

20% progress

-Rx slows progression, doesnt cure

Question 22

How much change in relative visual field scores can you expect after the first 24 months of treatment? Explain in terms of <14, <18, and >18mmHg IOP.

Answer 22

Little change in the first 24 months
IOP <14 - doesnt progress
IOP <18 - slow progression over 8 years, max loss over 20 years
IOP >18 - max loss in 15 years

Question 23

What is the maximum daily variation seen in most normal eyes? How does this relate to setting a target IOP?

Answer 23

4mmHg - 20% in eyes of 20mmHg

-20% is beyond normal physiological IOP variation (is therapeutic)

Question 24

What are the target IOPs for the following:
OAG (starting)
-early
-moderate
-advanced
Advanced
Progressing
Include both percentage and mmHg.

Answer 24

OAG (starting) (-25% / ≤18mmHg)
-early (-20% / ≤18mmHg)
-moderate (-25% / ≤18mmHg)
-HR OAG (-30% / ≤14mmHg)
Advanced (-30% / ≤14mmHg)
Progressing (add -20% / ≤14mmHg)

Question 25

By how much can target IOP be adjusted if the patient is stabled?

Answer 25

Max 4mmHg

Question 26

What is moderate and severe threat to fixation defined as on VF, and what constitutes advanced glaucoma?

Answer 26

Defined by dB at 4 central 24-2 points
15-25dB - moderate
Severe if 1 point has 0 to 15dB
-this is considered advanced glaucoma

Question 27

Are PGA effects fully expressed in low tension glaucoma?

Answer 27

Not

Question 28

Within what time period is IOP reduction evident for glaucoma drugs and which is the quickest?

Answer 28

All within a week - PGAs quickest (80% of effect within a week)

Question 29

How long do PGAs need to have the full therapeutic effect?

Answer 29

3-4 months

Question 30

Do glaucoma combination drugs give more or less than the full effect of each component?

Answer 30

Less

Question 31

Can the maximum effect of a glaucoma drug only be achieved from independent drug application?

Answer 31

Yes

Question 32

What IOP change would prompt a drug change? What should you do if you need only a small change (2mmHg)? What about a large change?

Answer 32

If IOP change is <5mmHg on review
Change to combination drug if small change required
Add independent combo for large change

Question 33

Can a third drug be added to a glaucoma therapy?

Answer 33

Yes, but contact an ophthalmologist first

Question 34

What percentage of glaucoma patients need one, two, and three drugs?

Answer 34

One - 69%
Two - 28%
Three - 3%