DIS - Glaucoma Management II - Week 7

Question 1

What percentage of low tension glaucoma patients will not progress after 6 years? What does this mean for treatment?

Answer 1

55% do not progress after 6 years

May not always need to treat

Question 2

What is the major component of low tension glaucoma and how does this affect the use of beta blockers as treatment?

Answer 2

Major vascular component

Beta blockers should be avoided due to a decrease in systemic blood pressure

Question 3

What is the target IOP for low tension glaucoma?

Answer 3

-30% or ≤12mmHg

Question 4

Compared to other forms of glaucoma, do PGAs generally have a greater or lesser effect on IOP in low tension glaucoma? What does this mean for reaching target IOP? Keeping this in mind, are they commonly used?

Answer 4

PGAs are commonly used, but have less effect in low tension glaucoma
Harder to get to target IOP

Question 5

What percentage of low tension glaucoma patients stop responding to latanoprost after 3 months?

Answer 5

43%

Question 6

What percentage of low tension glaucoma patients will reach their target IOP on PGA monotherapy? What percentage will need 2 drugs?

Answer 6

50% with monotherapy

50% will need 2 drugs

Question 7

If a patient requires 2 drugs for low tension glaucoma, what should be considered for the second drug (2), assuming the first is a PGA? What should this choice be based on?

Answer 7

Consider a vasomodifier
-CAI
-alpha agonist
Based on ON/VF loss

Question 8

Is timolol ideal to use alone for low tension glaucoma? Explain.

Answer 8

No, do not use timolol alone

It is ok in a combo if IOP is >15

Question 9

Does timolol give good IOP control? What about its night effect? Does it have any effect on systemic blood pressure? Explain.

Answer 9

Can give good IOP control but lacks night effect

Decreases systemic blood pressure, decreasing ocular perfusion pressure

Question 10

Is progression of glaucoma higher or lower in eyes treated with timolol at 4 years after diagnosis?

Answer 10

3 times higher

Question 11

What is a good single drug choice for low tension glaucoma? What about a combination therapy?

Answer 11

Tafluprost
Simbrinza
-CAI + alpha agonist

Question 12

How should cases of low tension glaucoma with IOP ≥15mmHg?

Answer 12

Prescribe as usual with target IOP at -30% or ≤12mmHg

Question 13

What syndrome is considered a risk factor for low tension glaucoma?

Answer 13

Reynaud’s syndrome

Question 14

Is migraine considered a risk factor for or protective against low tension glaucoma?

Answer 14

Risk factor

Question 15

What CDR is a risk factor for low tension glaucoma?

Answer 15

<0.8

Question 16

Which gender has a higher risk of low tension glaucoma?

Answer 16

Female

Question 17

How should cases of low tension glaucoma with IOP <15mmHg? Explain all approaches and why they are viable (2).

Answer 17

Not prescribing for IOP <15mmHg is a viable option
-untreated average rate of loss of VF is 0.33dB/year after 5 years
Treat all moderate+ VF loss
-PGA like tafluprost
-consider vasomodifiers as first call (CAI or alpha agonist) - based on ON/VF loss

Question 18

Consider a case of low tension glaucoma with <15mmHg IOP, early VF defect, and no foveal threat. How should this be managed? Include review schedule and what to do if it worsens.

Answer 18

Discuss with the patient
-explain 55% show no progression
Offer no treatment but must review if changes occur
Or offer to treat with a modified target (i.e. -10%)
Monitor 4/12 for progression for 2 years, then 12/12
If VF/ON/NFL worsens, establish -30% or <12mmHg target

Question 19

Consider a case of low tension glaucoma with advanced loss (MD < -12dB or foveal threat). What is the management (give an exmaple of a good Rx), what is the target IOP, is it easy to reach, and what is the review schedule? What should be done if it worsens?

Answer 19

Prescribe two drugs - not a combination therapy - one being vasoactive drug (CAI or alpha)
Tafluprost + simbrinza
Target -30% or <12mmHg
-hard to achieve
Monitor NFL/ON/VF 4/12 for progression
If no changes after 2 years, then review 6/12 or 12/12
If it worsens, set target to -50% or <10mmHg
-consider referral for surgical intervention

Question 20

Consider a case of low tension glaucoma with advanced loss (MD < -12dB or foveal threat). What is the management if there is fast progression, less than 1-2 years (4)?

Answer 20

DFE for retinal masquerades
Rule out primary angle closure glaucoma
Rule out retinal cause or ON/pathway compression (tumour) - scans
Refer for second opinion/surgery

Question 21

What is the surgical intervention for acute angle closure glaucoma?

Answer 21

Urgent bilateral paeripheral laser iridectomy

Question 22

What are four other cases for surgical intervention aside from an ocular emergency?

Answer 22

Poor/limited adherence (low dexterity/poor motivation etc)
Max meds fail to stabilise progression
Adverse effects to drugs
Failing to achieve target IOP
-do not rush, can take up to 18 months to reach target IOP before deciding for surgery

Question 23

In what three cases is surgery for glaucoma generally not needed?

Answer 23

If there is no progression
If only one eye is affected
Older age (80+)

Question 24

Is surgery common or uncommon for glaucoma in australia?

Answer 24

Not

Question 25

Does treatment stop glaucoma?

Answer 25

No

Question 26

What is expected to happen if glaucoma drops are deprescribed?

Answer 26

IOP will rise to pre-treatment levels
-is asymptomatic and may not be vision-threatening for people with mild glaucoma
Generally done for patients over 80

Question 27

List 5 factors against deprescribing glaucoma medication.

Answer 27

Advanced disc cupping
Advanced visual field loss
Visual field defect involving fovea
Loss of vision in one eye due to glaucoma
Known very high pre-treatment IOP (>35mmHg)

Question 28

Consider the point system for estimating 5-year risk of developing primary open angle glaucoma. At what percentage risk should you begin treatment? what is it only valid for?

Answer 28

Treat when risk is >15%

Only valid for ocular hypertension

Question 29

What is a better indicator of everyday capacity, integrated vidual fields, or binocular fields?

Answer 29

Integrated visual fields

Question 30

Describe the categories for QoL and driving based on MD of VF testing (3). Include cutoff MD for each category and whether they are ok to drive.

Answer 30

0 to -7dB
-ok to drive and have high QoL
-7 to -10dB - moderate deficit
-some QoL limitations, may be unfit to drive (must do BF to check)
-10 to -14dB - severe deficit
-most likely unfit to drive, must  do BF, expect majority to fail
Worse than -14dB - unfit to drive
-do IVF but expect majority to fail