• Angle closure – Iridotrabecular apposition
obstruction to aqueous outflow
Raised Intraocular pressure.
• Anatomical features : shallow AC
Increased anterior lens curve
Shorter Axial length
Smaller corneal diameter
Increased ratio of lens thickness to
Occludable Angle: When Pigmented trabecular meshwork is not visible
without indentation or manipulation in at least 3 or 4
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.
• ITC –iridotrabecular contact , PAS – Peripheral anterior synechiae
Positive family history for angle closure
Age over 40-50 yrs
History of Angle closure symptoms
Racial group Asians [far eastern]
• 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
• Non-pupillary block relating to the iris • Specific
anatomical factors include plateau iris (anteriorly
positioned ciliary processes), and a thicker or more
• 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 (Fig. 10.43).
• Plateau iris syndrome describes the occurrence of
angle-closure despite a patent iridotomy in a patient with
morphological plateau iris.
To determine topography of anterior chamber angle –angle width,level of iris
insert,shape of peripheral iris,apposition/synechiae.
Grade 4 (35–45°) is the widest angle,[ in which the ciliary body can be
visualized with ease]
Grade 3 (25–35°) is an open angle [ in which at least the scleral spur can
Grade 2 (20°) is a moderately narrow angle [in which only the trabeculum
can be identified
Grade 1 (10°) is a very narrow angle [ in which only Schwalbe line, and
trabeculum, can be identified.
Slit angle [ no obvious iridocorneal contact but no angle structures can be
Grade 0 (0°) is a closed angle due to iridocorneal contact and is recognized by the
inability to identify the apex of the corneal wedge. Indentation gonioscopy will
distinguish ‘appositional’ from ‘synechial’ angle closure
Slit lamp grading or PACD
• Van herrick method:
grade 0 – Iridocorneal contact ,
grade 1- PACD < ¼ CT
grade 2- pacd [1/4 to 1/2 ] CT
grade 3- not occludable > ½ CT
• Allows to visualize iris,iris root,CS
• To elucidate the mechanism of angle closure
Halos around lights
nausea and vomiting
1. Acute congestive glaucoma
Elevated IOP risen rapidly
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
2. 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
3 Resolved acute (post-congestive) angle
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
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.
• 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
• Paraphysiological test :
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
Initial management of PACG ATTACK
Immediately on attack
IV osmotic agent /acetazolamide
Corneal indentation using 4 mirror lens
Leave patient supine to allow lens move
back in position
If patient in pain
Topical ketorolac , systemic
If patient is vomiting
If patient comfortable
laser prophylactic iridectomy in fellow eye
Attack not broken
IV Osmotic if not already given
Attack not broken
Peripheral laser iridotomy :
• A procedure ,where 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
Examine patency and size of iridotomy with gonioscopy
Surgical peripheral iridectomy
• Removal of iris tissue by knife or scissors
• 2-3 mm peripheral corneal incision in
• Alternatively ,conjunctival peritomy and scleral
limbus incision ,nylon sutures wound closure
• Externalised iris piece held with toothed forceps ,
incised with fine scissors.
Argon laser iridoplasty
• Aim to shrink and flatten iris tissue without damage
• Placement of circumferential ring of non penetrating
contraction burns at far iris periphery – widen
• Evenly spaced applications [4-10 burns /quadrant , 200500 microns large
0.2-0.5 sec , low powered [200-400 mW] ,central button of
• Energy is defocussed so can be given in cloudy cornea also
• It involves stripping of peripheral anterior
synechiae using an Irrigation cyclodialysis
spatula / flat iris spatula.
• Viscoelastics used to deepen the anterior
Removal of lens with or without opacity due to
lens size / malposition.
Best outcomes with small incision phaco.
• Trabeculectomy lowers IOP - creating a fistula,
to allow aqueous outflow from the anterior
chamber to the sub-Tenon space. The fistula is
protected or ‘guarded’ by a superficial scleral
• When medical therapy has failed to achieve
adequate control of IOP.