POAG, its clinical signs, investigations and treatment.

1. At least 2 out of 3
If only 1 finding

3. • Disturbance of the structural or functional integrity of the optic nerve, in which;
IOP > 21 mmHg
Glaucomatous ONH damage
Characteristic visual field changes
Open AC angle
Absent signs of 2ry glaucoma or a non glaucomatous cause of optic
neuropathy

4. • The higher the IOP, the greater the likelihood of glaucoma
• More common in old age
• More common in Black individuals
• Siblings, offspring
• More common in Myopic individuals
• Hypertension, Diabetes, Migraine

5. • Direct mechanical damage to RNF
• Ischaemic damage

6. • Nothing
• Except in late cases when the patient complains of restricted visual field
• Steroids (elevates
IOP), ℬ blockers e.g.
for hypertension
(lowers IOP)
• Trauma, surgery, inflammation
• Cardiovascular,
respiratory disease; for
proper tailoring of
medications

7. • Phasing (Note time of the day), Asymmetry
• C/D ratio (Asymmetry), Peri papillary
area, RNFL defect
• Not affected except in advanced cases
• Not affected except in advanced cases (RAPD in post glaucomatous
OA)
• Open angle
• To exclude causes of 2ry glaucoma

8. • Measure IOP while the patient is fasting
• Drink 1 litre over 5 - 15 minutes
• Measure IOP subsequently every 15
minutes for one hour
• A rise in IOP of 6 to 8 mmHg or an increase
from baseline of 30% or more at any time
during the hour was considered a positive
test.

9. • To adjust the IOP reading according to the central corneal thickness.
• Pseudo-colour map of ONH & peri-papillary RNFL thickness.
• The visual field defect
corresponds to the pattern
of fibres in the retinal area
served

10. ‫مهم‬‫جدا‬
• can form at a relatively early stage, often superonasally
from the earliest to the latest

11. •the defect is bounded by the horizontal midline, corresponding to the retinal nerve
fibre layer horizontal raphe.

12. •Less common than nasal step, WHY?!!

13. •Develop from coalescent para-central scotomas
•Baring of the blind spot = extension from the blind spot around fixation

15. • Develops when superior and inferior arcuate defects become continuous

16. • A small island of central vision

17. • 1ry vs 2ry glaucoma
• Causes of visual field defects mimic glaucoma field defects e.g. ONH drusen, tilted
ONH
• Prevent functional impairment of vision within the patient’s lifetime by
slowing the rate of ganglion cell loss closer to that of the normal
population.

18. • Increases uveoscleral outflow
• Increases trabecular outflow
• Latanoprost
• Once daily at bed time
• Conjunctival hyperaemia
• Eye lash thickening, lengthening & hyper pigmentation
• Irreversible iris hyper pigmentation
• Peri ocular skin hyper pigmentation
• Cystoid macular edema
• Promotion of herpetic keratitis
• Anterior uveitis
• Travaprost • Bimatoprost

19. • Decreases aqueous production by ciliary epithelium
• Timolol
• Twice daily (not at bed time to avoid profound hypotension)
• Ocular: Allergy, PEE
• Systemic:
1. Bronchospasm; contraindicated in asthmatic patients
2. Bradycardia, Hypotension, Heart block, Heart failure
3. Dyslipidemia, headache, decrease lipido
• Betaxolol (increases ON blood flow) • Levobunolol

20. • Decreases aqueous production by ciliary epithelium
• Increases uveoscleral outflow
• Brimonidine
• Twice daily
• Ocular: Allergic conjunctivitis
• Systemic:
1. Xerostomia
2. Cross the blood brain barrier (CI under the
age of 2 years)
• Apraclonidine

21. • Decreases aqueous production by ciliary epithelium
• Dorzolamide
• Twice daily
• Ocular: Allergic blepharo-conjunctivitis
• Systemic:
1. Idiosyncrasy (Bone marrow suppression)
• Brinzolamide

22. •improve convenience and patient compliance
•more cost effective
• Timolol + Dorzolamide (Cosopt)
• Timolol + Travaprost (Duotrav)
• Timolol + Brimonidine (Combigan)

23. • Decreases aqueous production by ciliary epithelium
• Acetazolmide
• Used for control of acute attack of glaucoma with high IOP
• Ocular: Choroidal effusion
• Systemic:
1. Paraesthesia
2. Renal stones
3. GIT disturbances
4. Malaise

24. •Create an osmotic gradient so that water is ‘drawn out’ from the
vitreous into the blood
• Mannitol (IV)
• Used for control of acute attack of glaucoma with high IOP
• Systemic:
1. Cardiovascular overload
2. Urine retention
3. Headache
• Glycerol (Oral) • Isosorbide (Oral)

25. • Beta blockers
• CAI
• Alpha 2 agonists
• PG derivatives
• Alpha 2 agonists

26. • Start with single line (usually PG derivative or Beta blocker)
• Choose the drug with fewest side effects, lowest concentration
• Usually after 2-4 weeks
• Response to the drug is assessed against the desired target IOP
• Target IOP is tailored according to the patient:
Age
Presenting IOP
ONH changes
Field defects

27. • Subsequent assessment is set for further 3-6 months
• ONH exam is done in each visit
• Perimetry is done every 6-12 months
• Gonioscopy is done every 12 months as AC angle tend to narrow with age
• Patient compliance • Proper target
IOP setting
• Diurnal
variation

28. • Substitute to another drug, then review
• Add another drug or use fixed combination
Laser trabeculoplasty (LTP) involves the delivery of
laser to the trabecular meshwork with the aim of
enhancing aqueous outflow and thereby lowering
IOP.

29. ALT SLT
LASER Argon Nd YAG
Mechanism of
action
Thermal damage to TM, leading to
mechanical opening of TM spaces
Selectively target melanin pigment in
trabecular meshwork (TM) cells, leaving
non-pigmented structures unscathed.
Repeatability Not repeatable Could be repeated
Electron
Microscopy of TM

30. • Poorly controlled POAG with medical or laser therapy
• Poor compliance with medical treatment
• Advanced POAG requiring very low target IOP
• To create a fistula between the AC & the
sub-conjunctival space from which the
aqueous drains.

32. • Blebitis, Endophthalmitis
• Treatment; IV Fortified
antibiotics (Vancomycin +
Ceftazidime), Vitrectomy

33. • With Deep AC >> Filed bleb (Sub-conjunctival fibrosis)
• With Shallow AC >> Pupillary Block
>> Malignant Glaucoma (Aqueous misdirection)

34. • With Deep AC >> Choroidal detachment
• With Shallow AC >> Over Filtration
>> Bleb Leak

36. •In non-penetrating filtration
surgery the AC is not entered
and the internal trabecular
meshwork is preserved, thus
reducing the incidence of
postoperative over filtration with
hypotony & its potential sequelae.
•Two concentric lamellar scleral
flaps are fashioned & the deep
flap excised leaving behind a thin
membrane consisting of
trabeculum/Descemet membrane
through which aqueous diffuses
from the AC to the subconjunctival
space.