1. Review of Glaucoma Suspect
Shields’ Textbook of glaucoma, 6th edition
Becker-Shaffer's diagnosis and therapy of the glaucomas, 8th edition

2. Introduction Glaucoma suspect
Shields’ Textbook of glaucoma 6th edition (2010)
Ocular hypertension
1970s: IOP greater than 21 mmHg,
→ higher risk for developing COAG
Chandler & Grant: early open-angle glaucoma without damage
Glaucoma suspect
Shaffer: Glaucoma suspect
Consistently elevated IOP(>21mmHg)
optic nerve features suggestive of early glaucoma
suspicious visual field defects

3. Definition Normal appearing, open angle by gonioscopy,
and one of the following in at least one eye
IOP consistently above 21 mm Hg by applanation tonometry
Appearance of the optic disc or retinal nerve fiber layer suggestive of glaucomatous damage
Diffuse or focal narrowing or sloping of the disc rim
Diffuse or localized abnormalities of the nerve fiber layer, especially at superior and inferior poles
Disc hemorrhage
Asymmetric appearance of the disc or rim between fellow eyes (e.g., cup to disc ratio difference greater than 0.2) suggesting loss of neural tissue
Visual fields suspicious for early glaucomatous damage
Adapted from AAO, PPP, 2000

4. Prevalence and development of Open-Angle Glaucoma
The Glaucoma Suspect
‘Natural history’ of treated and untreated open-angle glaucoma
An individual without glaucoma.
Subthreshold axonal loss from glaucoma that does not progress beyond category.
Axonal loss from glaucoma that responds to treatment(*) compared to
Glaucoma that remains untreated because of a delay in diagnosis.
Aggressive axonal loss from glaucoma that is detected only after the onset of symptoms and progress to blindness despite treatment(**).
Shields’ Textbook of Glaucoma

5. PREVALENCE AND DEVELOPMENT OF OPEN-ANGLE GLAUCOMA
Prevalence rate : 4% to 10% in persons older than age 40 years(IOP greater than or equal to 21 mm Hg in one or both eyes (with normal visual fields and optic nerves))
Progression rate to COAG : approximately 1% per year over 5 to 15 years

7. OHTS (Ocular Hypertension Tx Study)
Design
Multicenter, randomized, prospective clinical trials
Purpose
To determine the efficacy of topical med. in delaying or preventing the onset of glaucoma in OHT
Subjects
24-32mmHg (21-32mmHg in other eye)
1636 pts between yrs
Topical ocular hypotensive treatment versus close observation 7

8. OHTS (Ocular Hypertension Tx Study)
Treatment goal
<24mmHg and at least 20%↓
COAG developing over 5 years
1% / year in the medication group
2% / year in the observation group
High risk factor (+) → 3~5% / year 8

9. High-Risk Glaucoma Suspects
High-risk glaucoma suspects include patients
who have one or more of the following:
IOP consistently > 30 mm Hg*
Thin central corneal thickness(dependent on ethnicity)
Vertical cup-to-disc ratio >0.7
Older age*
Abnormal visual field, e.g., increased pattern standard deviation on Humphrey Visual field test.
Presence of exfoliation or pigment dispersion syndrome.
Disc hemorrhage
Family history of glaucoma or known genetic predisposition.
Fellow eye of patient with severe unilateral glaucoma(excluding secondary unilateral glaucoma)
Additional ocular(e.g., suspicious disc appearance, myopia, low optic nerve perfusion pressure, steroid responder) or systemic risk factors that might increase the likelihood of developing glaucomatous nerve damage (e.g., African ancestry, sleep apnea, diabetes mellitus, hypertension, cardiovascular disease, hypothyroidism, migraine headache, vasospasm)
*These factors were identified as risk factors for development of chronic open-angle glaucoma in the Ocular Hypertension Treatment Study and European Glaucoma Prevention Study..

10. Screening IOP value of more than 21 mm Hg
Skilled optic nerve examination
Goldmann kinetic or Humphrey static (automated) perimetry
short wavelength automated perimetry (SWAP)
standard automated perimetry (SAP)
Frequency doubling perimetry (FDP)
Best method to detect early galucoma (AAO)
IOP, optic nerve and visual field.

11. DIAGNOSTIC ASSESSMENT
IOP AND PACHYMETRY
2.5 mmHg ~ 3.5 mmHg should be applied for every 50 microns of difference from 550 microns
SLIT-LAMP BIOMICROSCOPY AND GONIOSCOPY
To exclude angle closure or secondary cause of elevated IOP
angle recession, pigment dispersion, KP on the trabecular meshwork
FUNDUS EXAMINATION
optic nerve head, disc hemorrhage, nerve fiber layer
VISUAL FIELD
24-2 SITA, 24-2 Humphrey perimetry, SWAP, FDP (Matrix)
IMAGING of OPTIC NERVE and NFL
Confocal laser scannig tomography, OCT, scanning laser polarimetry
OCULAR BLOOD FLOW
Doppler flowmetry
Lower in superotemporal rim (16% lower), the cup (35%), and the inferotemporal neuroretinal rim (22%)

12. When To Treat?
Complex decision that involves consideration of many factors
Visual, physical, medical, psychological, and social circumstances

13. Indication for treatment
if early damage is detected or if the patient appears to be at high risk for developing POAG based on the risk factors
if the IOP is 30 mmHg or greater
prevalence of glaucoma at this pressure level is 11–29%
3. IOPs in the middle-to-upper 20s who also have one or more risk factors
Becker-Shaffer's diagnosis and therapy of the glaucomas, 8th edition

14. Possible indication of treatment
1. A one-eyed patient.
2. A young patient.
high pressure for many years vs more resistant to the effects of elevated IOP
3. Unreliable visual fields or optic disc assessment..
4. A patient who is content with treatment initiated by another physician and who is tolerating the medication well.
5. An ocular hypertensive patient who desires treatment.
6. An ocular hypertensive patient who has developed a vascular occlusion in either eye.
Becker-Shaffer's diagnosis and therapy of the glaucomas, 8th edition

15. Treatment in Glaucoma Suspect with elevated IOP
Stratify pts.
High risk : Suggest treatment be initiated
Mod. risk : Can initiate treatment if appropriate, or monitor closely
Low risk : Monitor IOP as well as optic nerve structure and function, and treat if evidence of progression
Carefully consider theses factors when deciding whether to treat.
Greater age and life expectancy
Psychological factors
Convictions(patient and physician)
Social environment
Availability for follow up
Pregnancy

16. Various Types and Managements of Glaucoma Suspect
Becker-Shaffer's diagnosis and therapy
of the glaucomas, 8th edition

17. Glaucoma Suspect Type I Glaucoma Suspect Type II
Normal Intraocular Pressure, No Damage
Strong family history of glaucoma
Retinal vascular occlusion
Exfoliative syndrome
Angle recession
Pigmentary dispersion syndrome
Narrow angles
Uveitis
History of halos
Management : Monitor periodically and inform patient of need for follow-up
Glaucoma Suspect Type II
Normal Intraocular Pressure, Possible Damage
Suspicious optic disc
Suspicious nerve fiber layer defects
Suspicious visual field
Reduced psychophysical function
Management : Confirm the finding by repeat testing if needed, as with suspicious visual fields. Demonstrate a normal variant, another cause of damage, or an elevated intraocular pressure(IOP) expressed at other time. If the patient demonstrates increased IOP, then treat for glaucoma. Otherwise. Treat any other existing disease or conduct annual or semi-annual examinations depending on risk factors.

18. Glaucoma Suspect Type III Glaucoma Suspect Type IV
High Intraocular Pressure, No Damage
Management :
1. Pressure > 35 mmHg(some authorities choose > 30 mmHg) : Risk of damage is great. Treat.
2. Pressure mmHg : Treat if (1) other eye has damage, (2) patient is elderly or has siblings or parents with glaucoma, (3) patient has other risk factors, (4) patient has complicating ocular or vascular disease, or (5) there is poor patient follow-up or poor compliance. If treatment is poorly tolerated, treatment may be stopped and the patient observed at least every 5 months for progression of the disease.
3. Pressure mmHg : Treat if other eye has damage. Otherwise, observe. Some authorities would treat if the risk factor(s) above exist.
4. Pressure ≥ 25 mmHg and very narrow angles : consider laser iridotomy.
Glaucoma Suspect Type IV
High Intraocular Pressure, Possible Damage
Peripheral anterior synechiae and narrow angles
Notch or local rim narrowing of optic nerve
Early arcuate scotoma or paracentral scotoma
Management : Generally, treat such eyes, especially if the other eye has damage, the patient has strong family history, or the patient has a complicating ocular disease.

19. Follow up IOP, optic nerve head, visual field status
Depends on several factors
Receiving medical therapy
Target IOP range
Risk factor
At least 6 to 12 months
At each visit, IOP
Visual field : once every 6 to 18month
Gonioscopy: suspicion of angle closure or other angle abnormality

20. Follow up

21. OHT Follow-up From EGS guideline 3rd edition (2008)
Follow-up at intervals of 12 months initially,
to be increased if all parameters remain negative, with exam:
Optic disc VF
IOP
ONH & RNFL photographs initially and every 2-3 years