Management of Primary Glaucomas - Decision Making in Prescribing

List the 6 general steps followed when treating a glaucoma pt

• Establish a diagnosis

• Establish baseline IOP, Fields, OCTs, and Photos

• Set a target IOP

• Initiate therapy to lower IOP to target

• Follow-up

• Reasses

Why is it so important to establish a specific dx when beginning to manage you glaucoma pt

different dx require different therapies and respond differently to certain therapies

if you are initiating a therapy and they are not responding well... that may be a sign of mis-dx

Give the 2 reasons why is it a key goal of glaucoma management to diagnosis glaucoma at an early, pre-symptomatic stage

- there is less response to therapy in a later stage disease

- there is increased risk of going blind despite good IOP control in later stages of the disease

List the 2 major challenges that clinicians managing glaucoma face

1. identifying subtle glaucoma

2. knowing when to treat vs when to watch

Boht missing a dx & treating unnecessarily are bad, but which one is generally worse

"failure to diagnose" is the most common lawsuit

(young/old) pt typically endure a more aggressive therapy plan, why

young

because they have more relative life span - therefore are more likely to go blind in their lifetime if they are not treated

Currently, _____ is the only known modifiable risk factorto delay the progression of glaucoma

IOP

List the 3 current tx options target IOP reduction to delay progressive glaucomatous damage and to delay onset of visual field loss

• Topical medications

• Laser trabeculoplasty

• Surgical drainage procedures

The Baltimore Eye Survey confirmed that while IOP was a major risk factor, _____% of the glaucoma patients had an IOP less than 21mmHg on diagnosis!

50%

(T/F) A certain IOP is equal to glaucomatous optic neuropathy

FALSE

If the pressure is too high for that INDIVIDUAL eye, then GON occurs

Define Target IOP

the upper limit of the range of measured IOP adequate to stop progressive pressure-induced injury of the ONH

OR

The highest IOP in a "given eye" which does not contribute to the development of clinically apparent glaucomatous optic nerve damage

(T/F) Target IOP can is periodically re-evaluated and revisited and may need to be changed as time goes on

TRUE

List the 4 most important factors to consider when picking target IOP for a pt

• Severity of glaucoma (ONH &VF)

• Baseline IOP

• Age

• Life expectancy

image slide 17

List 7 "other" risk factors to consider when picking target IOP for a pt

(excluding the 4 most important)

- severe damage in other eye

- fam hx of blindness from glaucoma

- high myopia

- ethnicity

- vascular risk factors

- rate of progression to date

- CCT

What is the general tx plan of a pt with early glaucoma/OHT diagnosed late inlife or with limited life expectancy

no tx required - observation

graph slide 18

What is the general tx plan of a pt with moderate glaucoma diagnosed at age of 50+

tx with meds and/or laser to lower IOP by 30%... may slow the rate of deterioration so that the patient never experiences visual problems

What is the general tx plan of a pt with advanced glaucoma and significant risk for functional loss

tx with meds and/or laser to lower IOP to the low teens... may slow the rate of deterioration so that the patient never experiences visual problems

What is the #1 most important factor when setting target IOP

severity of glauoma

What 2 things are assessed to determine the severity of glaucoma

- ONH evaluation

- VF loss

(essentially whichever one is worse is how the pt is classified)

(T/F) Visual field loss encroaching on fixation should prompt the physician to set a low target IOP regardless of baseline pressure

TRUE

this is nearing functional visual field loss

To establish a baseline IOP ideally, 24 hour diurnal curve could be created... however this is unpractical so the best estimate is to:

get 4-6 IOP readings at different times of day

There is a gradual, steady decrease in the number of nerve fibers in the ONH with age... about ___-___% decrease per decade after age 50 years

4-5%

(T/F) Older individuals may not need as aggressive lowering of IOP compared to younger individuals

TRUE

this is due to life expectancy

Pt with a low corneal hysteresis have a (low/high) response to tx and a (low/high) ruck of progressing

- high response to tx

- high risk of progressing

Give the range of CTT that is considered to be average

545-555 um

(anything lower = thin

anything higher = thick)

Give the name and findings of OHTS

Ocular Hypertension Treatment Study

findings:

20% reduction of IOP from baseline leads to a lower rate of glaucoma in OHT patients

Give the name and findings of LPGTS

Low Pressure Glaucoma Treatment Study

findings:

NTG patients treated with Brimonidine are LESS likely to have VF progression than those treated with Timolol

Possibly due to neuro-protective effects of Brimonidine

(did not use Latanoprost because this was an older study and Latanoprost was not commonly used at the time)

Give the name and findings of CIGTS

Collaborative Initial Glaucoma Treatment Study

findings:

found 35% reductions with meds and 48% reductions with surgery

but overall glaucoma progress will be minimal if patients are treated aggressively to achieve low target IOP regardless of tx method

Give the name and findings of EMGT

Early Manifest Glaucoma Trial

findings:

25% reduction in IOP reduced risk of progression by 50%

&

Every 1mm drop in IOP, reduces risk of progression by 10%

Give the name and findings of AGIS

Advanced Glaucoma Intervention Study

findings:

- pt w consistent IOP <18mmHg show almost no VF loss

- pt w 17.5mmHg or greater show significant worse VF loss when compared to pt w 14mmHg or less

- pt w consistent IOP <12.3mmHg show NO glaucoma progression

What is unique about the values presented int he AGIS study

they use a true mmHg measure and not a % of reduction

Give the name and findings of CNTGS

Collaborative Normal Tension Glaucoma Study

findings:

30% IOP reduction from baseline delayed progression of glaucoma

Which population of pt was studied in OHTS

OHTN

Which population of pt was studied in EMGT

POAG

Which population of pt was studied in CNTGS

NTG

Which population of pt was studied in CIGTS

newly dx POAG

Which population of pt was studied in AGIS

POAG not controlled w meds

Go learn the table of the studies on slide 26

ok fine

How is true baseline, or Tmax established through IOP

4-6 IOP readings, at least 2 in the morning and 1 to 2 in the late afternoon/evening

Peak (Tmax s meds) can be closely attained between which hours of the day..... there is a ___% likelihood of these readings being close to peak IOP

7:00 and 9:00am

75% chance

According to AAO recommendation for IOP-lowering in glaucoma and OHT..... we should aim for a ____% reductions in:

- mild damage pt

- advanced damage pt

- NTG pt

- OHT pt

- mild damage pt - 30%

- advanced damage pt - 40%

- NTG pt - 30%

- OHT pt - 20%

in POAG

According to the Guidelines of the European Glaucoma Society, what should be the target IOP of:

- early glaucoma pt

- moderate glaucoma pt

- advanced glaucoma pt

- terminal glaucoma pt

- early glaucoma pt: <18mmHg

- moderate glaucoma pt: <15mmHg

- advanced glaucoma pt: <12mmHg

- terminal glaucoma pt: <10mmHg

in NTG

According to the Guidelines of the European Glaucoma Society, what should be the target IOP of:

- early glaucoma pt

- moderate glaucoma pt

- advanced glaucoma pt

- early glaucoma pt: <15mmHg

- moderate glaucoma pt: <12mmHg

- advanced glaucoma pt: <10mmHg

What is the recommended target IOP Reductions Required to Reduce the Rate of POAG Related Damage in...

Ocular hypertensive patients who have risk factors such as ethnicity, vascular compromise, etc.

20%

What is the recommended target IOP Reductions Required to Reduce the Rate of POAG Related Damage in...

Early to moderate glaucoma patients who have been identified by field loss

30%

What is the recommended target IOP Reductions Required to Reduce the Rate of POAG Related Damage in...

Patients with moderate to severe glaucoma as identified by field loss and optic nerve head appearance

40-50%

(or near EVP)

(T/F) Having a target IOP documented as "as low as can possibly get it" is acceptable

TRUE

All glaucoma pt are seen at least every __________ even if they are at their target IOP and not progressing

6 months

All pt with POAG should be monitored closely for the first _________ to determine rate of progression

2 years

Progression despite achieving target IOP offers the clinician which 3 choices:

1) Are IOPs measured clinically an accurate reflection of IOP at other times? (compliance or diurnal)

2) Should we further lower the IOP medically?

3) Should we further lower the IOP surgically?

What is the limitations of using IOP measurements to determine a target IOP

numerous reasons for inaccurate tonometry

(if target IOP = 14 and you get a IOP = 16 reading, this is nor enough to immediate change the therapy.... this signifies the need to repeat tonometry on a subsequent visit)

What is the limitations of IOP fluctuations when it comes to target IOP

majority of patients with advanced glaucoma have IOP spikes away from office hours... so the Tmax used to determine a target may not be the true Tmax of that pt

What is the limitations of setting a very low target IOP

Benefit to setting the target <10mmHg is questionable... usually IOPs this low require surgery and with surgery comes risks so need to ensure the benefit is worth the risk for that pt

(T/F) Reaching a target IOP signifies contorl of the disease process

FALSE

target does not equal control

test results and lack of strucutural and functional changes equal control

just becuase a pt is at the target IOP that you once set for them does not mean they are under control they must continue to be monitored until lack of progression is evident

List 6 considerations that should be made to acheive successful glaucoma management

- target IOP

- side effects/contraindications

- cost and availability

- ease of instillation

- compliance issues

- pt understanding

(T/F) All instructions to pt should be given both verbally and written

TRUE

it is essential to communicate well to the pt and ensure they understand the goals, potential adverse effects, what they should report back to you or any troubles they may have

A dilated-pupil fundus examination and perimetry should be performed at least __________ year for all glaucoma pt

one time per year

Every patient diagnosed with glaucoma should be seen at least every ______

6 months

Time interval of f/u depends on which 3 characteristics

- IOP level

- disease stage

- stability

What is the recommended frequency of follow up for OHT pt

every 3 - 6 months

depending on the duration of IOP control

What is the recommended frequency of follow up for pt with stable mild-stage disease

every 3 - 6 months

depending on the duration of IOP control

What is the recommended frequency of follow up for pt with stable moderate-stage disease

every 2 - 4 months

depending on the duration of stability and the IOP

What is the recommended frequency of follow up for pt with stable severe disease

every 1 - 3 months

depending on the duration of stability and the IOP

What is the recommended frequency of follow up for pt with recently established stability

every 1 - 3 months

depending on the severity and the IOP

What is the recommended frequency of follow up for pt with unstable disease

cases in which IOP, ON, or VF is unstable require adjustment of therapy, which could involve weekly or biweekly follow-up for a brief period or until stability is achieved