This document discusses primary angle closure glaucoma (PACG). It begins by describing the stages of PACG from primary angle closure suspect to primary angle closure glaucoma. It then covers risk factors, mechanisms (including pupillary block and non-pupillary block), signs and symptoms, investigations, and treatment approaches including laser iridotomy, medications, and surgery. The treatment goal is to eliminate iris blockage and lower elevated intraocular pressure to prevent optic nerve damage.

1. Dr Md Ferdous Islam
Dept of Ophthalmolgy
CMH,Dhaka
PRIMARY
ANGLE
CLOSURE
GLAUCOMA

2. Angle Closure
Occlusion of the Trabecular Meshwork by the
peripheral iris(iridotrabecular contact-ITC)
obstructing the aqueous outflow

3. Stages In Natural History
1 Primary angle-closure suspect (PACS)
• Gonioscopy shows posterior meshwork ITC in
three or more quadrants but no PAS
• Normal IOP, optic disc and visual field
2 Primary angle-closure (PAC)
• Gonioscopy shows three or more quadrants of
ITC with raised IOP and/or PAS, or excessive
pigment smudging on the TM
• Normal optic disc and field
3 Primary angle-closure glaucoma (PACG)
• Gonioscopy shows ITC in three or more
quadrants
• Optic neuropathy

4. Risk Factors
• Positive family history for angle closure
• Age : relative pupillary block 60 yrs or over. Younger
for non pupillary block
• Women
• History of Angle closure symptoms
• Hypermetropia
• Axial length
• Racial group Indian Asians & Far Eastern

5. Mechanism
Relative Pupillary Block
• Failure of aqueous flow through the mid dilated
pupil leads to a pressure differential between the
anterior and posterior chambers, with resultant
anterior bowing of the lax iris [Iris bombe] blocks
trabecular meshwork and iridolenticular contact

6. Non-pupillary block
• Specific anatomical factors include plateau iris
(anteriorly positioned ciliary processes), and a
thicker or more anteriorly-positioned iris
• Plateau iris configuration is characterized by a flat
central iris plane in association with normal central
anterior chamber depth. The angle recess is very
narrow, with a sharp iris angulation over anteriorly
positioned and/or orientated ciliary processes
• Plateau iris syndrome describes the occurrence of
angle-closure despite a patent iridotomy in a
patient with morphological plateau iris

7. • Lens induced angle closure
• Retrolenticular
• Combined mechanism
• Reduced aqueous outflow

8. Shaffer grading

9. Ocular Manifestations
• Symptoms
Decreased vision
Halos around lights
Frontal headache
Ocular pain
Nausea and vomiting
Precipitating factors
Watching TV in a dark room
Pharmacological Mydriasis
Sympathetic agonist (Inhalers)

10. Signs
APAC
Elevated IOP risen rapidly
Conjunctival congestion
Corneal epithelial /stromal edema
Shallow or flat peripheral AC
Mid dilated [vertical oval] pupil
Absent /sluggish pupil reaction
Fellow eye generally shows an occludable angle
Subacute Angle Closure

11. Resolved APAC
• Folds in Descemet membrane (if IOP has been
reduced rapidly), optic nerve head congestion and
choroidal folds.
• Later iris atrophy [spiral-like configuration],
irregular pupil, posterior synechiae and
glaukomflecken
• Iris torsion

12. Chronic Presentation
• ‘Creeping’ angle-closure [gradual band-like anterior
advance of the apparent insertion of the iris].
From deepest part of the angle and spreads
circumferentially
• Episodic (intermittent) ITC is associated with the
formation of discrete PAS, individual lesions having
a pyramidal (‘saw-tooth’) appearance
• Disc cupping /nerve fibre defects with or without
visual field defect

13. Sequence Of Events
• Acute angle closure
sudden ,circumferential , iridotrabecular
apposition-rapid severe rise in IOP
• Intermittent angle closure
Self limiting episodes of ITC ,milder signs &
symptoms of former
• Creeping angle closure
slowly progressive ITC –Elevated IOP
• Chronic angle closure
irreversible , iridotrabecular adhesion
,asymptomatic unless significant raised IOP

14. Investigations
1. Anterior segment OCT
2. Anterior chamber depth measurement
3. Posterior segment USG
4. Provocative tests
Pharmacological test
 pupillary block mechanism in mid dilated state ,increased
tension of iris .
 Performed with short acting mydriatic [phenylephrine eye
drops]
if test proves positive –acute attack may be triggered

15. Dark room prone test
pupil dilates in dark,lens moves forwards in prone.
- Patient sits for 30 minutes in dark with head
prone ,no sleeping
- IOP checked rapidly ,positive if increases by 8 mm
Hg

16. Treatment
APAC
Initial Treatment
1.Supine Position
2. IV Acetazolamide 500mg if IOP >50mm of Hg. oral if <50mm
of Hg
3.Additional oral dose of 500 mg of Acetazolamide
4.Apraclonidine 0.5%-1%,timolol 0.5%,prednisolone 1%
5.Pilocarpine 2-4% 1drop ½ hourly repeatedly,1% 1 drop to the
fellow eye
6. Analgesic and antipyretic

17. Resistant case
1.Central corneal indentation
2.Further pilocarpine, timolol, apraclonidine, prednisolone
3.Mannitol 20% IV 1-2gm/kg over 1 hr, oral glycerol 50%
1gm/kg or oral isosorbide 1gm/kg
4.Paracentesis
5.Clearing cornel oedeme with glycerol
6.Surgical :PI, Laser iridotomy, iridoplasty, lens extraction,
goniosynechialysis,trabeculectomy
Subsequent Med Treatment
1.Pilocarpine 2% 4 times to affected eye,1% 4 times to
fellow eye
2.Topical steroid 4 times
3.(Any of ) timolol or apraclonidine or oral acetazolamide

18. PACS
1.Laser iridotomy
2. If ITC persists –laser iridoplasty, long term pilocarpine
prophylaxis, lens extraction
PAC & PACG
1.As for PACS but urgency & intensity of treatment with
frequent review with anti glaucoma medications and
neuroprotective drugs.

19. Peripheral Laser Iridotomy
• A hole is made in iris periphery allowing aqueous to drain
from PC into TM
• Helps eliminate high aqueous pressure behind iris and iris
falls back.
• Done using Nd:YAG laser ,150-200 microns size 3-6 mj of
power based on thickness
• Topical pilocarpine 30 mins before laser therapy, identify
crypt in iris and create opening
• Post op steroids and antiglaucoma meds

20. Surgical Peripheral Iridectomy
• Removal of iris tissue by knife or scissors
• 2-3 mm peripheral corneal incision in
superotemporal site
• Alternatively ,conjunctival peritomy and scleral
limbus incision wound closure
• Externalised iris piece held with toothed forceps ,
incised with fine scissors