FirstRanker Logo

FirstRanker.com - FirstRanker's Choice is a hub of Question Papers & Study Materials for B-Tech, B.E, M-Tech, MCA, M.Sc, MBBS, BDS, MBA, B.Sc, Degree, B.Sc Nursing, B-Pharmacy, D-Pharmacy, MD, Medical, Dental, Engineering students. All services of FirstRanker.com are FREE

📱

Get the MBBS Question Bank Android App

Access previous years' papers, solved question papers, notes, and more on the go!

Install From Play Store

Download MBBS Ophthalmology PPT 46 Primary Angle Closure Glaucoma 3 Lecture Notes

Download MBBS (Bachelor of Medicine, Bachelor of Surgery) Ophthalmology PPT 46 Primary Angle Closure Glaucoma 3 Lecture Notes

This post was last modified on 07 April 2022




PRIMARY ANGLE CLOSURE

--- Content provided by FirstRanker.com ---

GLAUCOMA

Acknowledgement

? Figures and photographs

--- Content provided by FirstRanker.com ---

Courtesy : Kanski's Clinical Ophthalmology

2
Learning Objectives

--- Content provided by FirstRanker.com ---

? At the end of this class the students shal be able

to :

? Define primary angle closure glaucoma.

--- Content provided by FirstRanker.com ---


? Understand the pathophysiology and the risk

factors.

--- Content provided by FirstRanker.com ---

? Be able to classify primary angle closure

glaucoma.

? Understand the fundamentals of managing

--- Content provided by FirstRanker.com ---


primary angle closure glaucoma

3

--- Content provided by FirstRanker.com ---

DEFINITION

? Primary angle closure glaucoma is a type of

primary glaucoma(with no obvious systemic or

--- Content provided by FirstRanker.com ---


ocular cause) characterized by

occludable/closed angles leading to

--- Content provided by FirstRanker.com ---

obstruction of aqueous outflow resulting in

rise of intra ocular pressure, optic nerve

damage and visual field defects.

--- Content provided by FirstRanker.com ---


4


ANGLE OF ANTERIOR CHAMBER

--- Content provided by FirstRanker.com ---


? STRUCTURES

? Schwalbe's line
? Trabecular meshwork

--- Content provided by FirstRanker.com ---

? Scleral spur
? Ciliary body band
? Root of iris

5

--- Content provided by FirstRanker.com ---


DRAINAGE OF AQUEOUS HUMOR

6

--- Content provided by FirstRanker.com ---


PRIMARY ANGLE CLOSURE

GLAUCOMA

--- Content provided by FirstRanker.com ---

EPIDEMIOLOGY

? PACG is the major cause of glaucoma blindness

worldwide.

--- Content provided by FirstRanker.com ---


? Age :- Average age at presentation 50-60 yrs

? Gender :- F > M, 4 : 1

--- Content provided by FirstRanker.com ---

? Race :-seen commonly in South-East Asian

population, Chinese and Eskimos

? Heredity :- mostly sporadic but may be inherited

--- Content provided by FirstRanker.com ---


AD/AR

? first degree relatives are at increased risk.

--- Content provided by FirstRanker.com ---

? Refractive error :- more common in

hypermetropes

7

--- Content provided by FirstRanker.com ---


Ocular risk factors

1. Shallow anterior chamber both

--- Content provided by FirstRanker.com ---

centrally and peripherally.

2. Decreased anterior chamber volume.

3. Short axial length of the globe.

--- Content provided by FirstRanker.com ---


4. Small corneal diameter.

8

--- Content provided by FirstRanker.com ---


Ocular risk factors

5.Decreased posterior corneal radius of

--- Content provided by FirstRanker.com ---

curvature

6.Anterior position of the lens with respect to

the ciliary body.

--- Content provided by FirstRanker.com ---


7.Increased curvature of the anterior surface &

thickness of lens

--- Content provided by FirstRanker.com ---

9

PATHOGENESIS

? It is incompletely understood.

--- Content provided by FirstRanker.com ---


? a. Iris?pupil obstruction (e.g., `pupil ary block')
? b. Ciliary body anomalies (e.g., `plateau iris syndrome')
? c. Lens?pupil block (e.g., `phacomorphic block' (swollen

--- Content provided by FirstRanker.com ---

lens or microspherophakia))

? Relative Pupillary block
? Normal y the pressure in the post. chamber exceeds that in the ant.

--- Content provided by FirstRanker.com ---

chamber due to physiological degree of resistance at the pupil ,since the

iris rests posteriorly on the anterior lens capsule.

10

--- Content provided by FirstRanker.com ---



Anterior Iris Bowing

Simultaneous dilatation of the pupil renders the peripheral

--- Content provided by FirstRanker.com ---


iris more flaccid. The pupil block causes the pressure in the

Posterior Chamber to increase & peripheral iris bows

--- Content provided by FirstRanker.com ---

anteriorly

11

Iridocorneal contact

--- Content provided by FirstRanker.com ---


Eventually the iris touches the posterior corneal surface,

obstructing the angle and the IOP rises.

--- Content provided by FirstRanker.com ---

12
Precipitating factors

1. Factors that produce mydriasis

--- Content provided by FirstRanker.com ---

? Dim illumination
? Emotional stress(due to increased sympathetic tone)
? Drugs

? Mydriatic agents :

--- Content provided by FirstRanker.com ---


? cyclopentolate, tropicamide, atropine, homatropine.

? Antipsychotic agents

--- Content provided by FirstRanker.com ---

? Phenothiazines: e.g., perphenazine ,fluphenazine
? Anticonvulsants e.g., Topiramate

13

--- Content provided by FirstRanker.com ---

? Antidepressants

? Tricyclic agents: amitriptylene ,imipramine
? Non-tricyclic agents: fluoxetine

--- Content provided by FirstRanker.com ---

? Antiparkinsonian agents : Trihexyphenidryl

? Antispasmolytics : Propantheline ,Dicyclomine

? Sympathomimetic agents : Adrenaline (epinephrine),

--- Content provided by FirstRanker.com ---


ephedrine, phenylephrine.


14

--- Content provided by FirstRanker.com ---

CLASSIFICATION

A. Primary angle-closure disease

? Irido-trabecular contact is the final common pathway of

--- Content provided by FirstRanker.com ---


angle closure disease, obstructing aqueous outflow

1. New classification
Primary angle closure suspect/PACS

--- Content provided by FirstRanker.com ---

Primary angle closure/PAC
Primary angle-closure glaucoma/PACG
2. Old classification

Angle closure suspect

--- Content provided by FirstRanker.com ---

Intermittent (sub acute) angle closure
Acute angle closure
Chronic angle closure
Absolute angle closure

--- Content provided by FirstRanker.com ---

15

New classification of PACG

qPrimary angle closure suspect/PACS

--- Content provided by FirstRanker.com ---


Has occludable/narrow angles
qPrimary angle closure/PAC

Has occludable/narrow angles +

--- Content provided by FirstRanker.com ---


High IOP/Peripheral anterior synechiae/

Excessive trabecular meshwork

--- Content provided by FirstRanker.com ---

pigmentation
qPrimary angle-closure glaucoma/PACG

PAC+ Optic disc changes+ Visual field

--- Content provided by FirstRanker.com ---

defects

16
Gonioscopic grading of Angle

--- Content provided by FirstRanker.com ---

closure

? Several grading systems :- Shaffer's, Spaeth's,

Scheie's.

--- Content provided by FirstRanker.com ---


? Shaffer's grading

Grade Angle width configuration

--- Content provided by FirstRanker.com ---

Chances of

Structures visible

closure

--- Content provided by FirstRanker.com ---


IV

35?-45?

--- Content provided by FirstRanker.com ---

Wide open

Nil

SL,TM,SS,CBB

--- Content provided by FirstRanker.com ---


I I

20?-35?

--- Content provided by FirstRanker.com ---

Open angle

Nil

SL,TM,SS

--- Content provided by FirstRanker.com ---


I

20?

--- Content provided by FirstRanker.com ---

Moderately open Possible

SL,TM

I

--- Content provided by FirstRanker.com ---


10?

Very narrow

--- Content provided by FirstRanker.com ---

Highly likely

SL only

0

--- Content provided by FirstRanker.com ---


0?

Closed

--- Content provided by FirstRanker.com ---

Closed

None

17

--- Content provided by FirstRanker.com ---


---------
Grade
IV

--- Content provided by FirstRanker.com ---

II

II

I

--- Content provided by FirstRanker.com ---

0

18


--- Content provided by FirstRanker.com ---

Van Herrick's grading

19

Tests for Angle closure

--- Content provided by FirstRanker.com ---


? Eclipse test : uses flash light to make a rough

assessment of angle depth

--- Content provided by FirstRanker.com ---

? Provocative tests for PAC suspects
?Prone- darkroom test: An increase in IOP of more

than 8mm Hg after one hour suggests PAC

--- Content provided by FirstRanker.com ---

?Mydriatic provocative test: Not preferred now

qFincham's Test: Also known as stenopaeic-slit test.

Glaucomatous halos remain intact , whereas

--- Content provided by FirstRanker.com ---


halos due to cataract are broken up into segments



--- Content provided by FirstRanker.com ---

20




--- Content provided by FirstRanker.com ---

PRIMARY ANGLE CLOSURE GLAUCOMA SUSPECT

? Also known as Latent PACG
? Essentially, the term implies

--- Content provided by FirstRanker.com ---

an anatomically predisposed

eye.

? Symptoms :- absent

--- Content provided by FirstRanker.com ---

? Signs :

? Axial AC depth is < normal

& iris lens diaphragm is

--- Content provided by FirstRanker.com ---


convex

? Close proximity of the iris

--- Content provided by FirstRanker.com ---

to the cornea

? Gonioscopy :- occludable

angle(grade 1 or 0)

--- Content provided by FirstRanker.com ---


without indentation in at

least 3 quadrants.

--- Content provided by FirstRanker.com ---

21

?Clinical course without

treatment may be:

--- Content provided by FirstRanker.com ---


IOP may remain normal

Acute or sub acute angle

--- Content provided by FirstRanker.com ---

closure may ensue

Chronic angle closure may

develop, without acute or

--- Content provided by FirstRanker.com ---


sub acute stages.

22

--- Content provided by FirstRanker.com ---


? Treatment
? Without treatment , risk of an acute pressure rise during the next

5 years is about 50 %.

--- Content provided by FirstRanker.com ---


? The need to treat is based on following criteria:-

? If one eye has had acute or subacute angle closure, then

--- Content provided by FirstRanker.com ---

fellow eye should undergo prophylactic peripheral laser
iridotomy (Laser PI)

? If both eyes have occludable angles, laser PI may be done

--- Content provided by FirstRanker.com ---

23

INTERMITTENT(SUBACUTE)PRIMARY ANGLE CLOSURE

GLAUCOMA

--- Content provided by FirstRanker.com ---


? A form of pupillary block glaucoma, which may not have

any recognizable symptoms.

--- Content provided by FirstRanker.com ---

? Occurs in a predisposed eye with an occludable angle in

association with intermittent pupillary block.

? Precipitating factors :- physiological mydriasis , or

--- Content provided by FirstRanker.com ---


physiological shallowing of AC when patient assumes a

prone or semi prone position ;emotional stress.

--- Content provided by FirstRanker.com ---

24


? Symptoms

--- Content provided by FirstRanker.com ---

? Characteristic h/o transient blurring of vision with haloes

around lights

? Ocular discomfort or frontal headache

--- Content provided by FirstRanker.com ---

? Attacks are recurrent and are usually broken after 1-2 hrs by

physiological miosis.

? Signs

--- Content provided by FirstRanker.com ---


? During an attack , eye is usually white
? In between attacks, eye looks normal although the angle is

narrow.

--- Content provided by FirstRanker.com ---


? Clinical course

? Without treatment is variable

--- Content provided by FirstRanker.com ---

? Some eyes develop an acute attack
? Others chronic angle closure

? Treatment:- Prophylactic laser PeripheraI Iridotomy(PI)

--- Content provided by FirstRanker.com ---

25

ACUTE PRIMARY ANGLE CLOSURE GLAUCOMA

? Sight threatening emergency

--- Content provided by FirstRanker.com ---

? Painful loss of vision due to sudden and total

closure of the angle.

? VA usually 6/60-Hand Movements.

--- Content provided by FirstRanker.com ---

? IOP is usually very high (40?70 mmHg).

26
Findings during an acute attack of angle-closure glaucoma
? Two of the following symptom sets:

--- Content provided by FirstRanker.com ---


? Periorbital or ocular pain
? Diminished vision
? Specific history of rainbow haloes with blurred vision

--- Content provided by FirstRanker.com ---

? IOP > 21 mmHg plus three of the following

findings:

? Ciliary flush (perilimbal conjunctival hyperemia)

--- Content provided by FirstRanker.com ---

? Corneal edema (epithelial,stromal)
? Shallow anterior chamber

27

--- Content provided by FirstRanker.com ---

Findings during an acute attack of angle-closure glaucoma

? Anterior chamber cell and flare
? Mid-dilated ,vertically oval and sluggishly reactive

--- Content provided by FirstRanker.com ---

pupil

? Closed angle on gonioscopy
? Hyperemic and swollen optic disc(due to

--- Content provided by FirstRanker.com ---

decreased axoplasmic outflow)

? Constricted visual fields

28

--- Content provided by FirstRanker.com ---

? MANAGEMENT

? Patient comfort ,lowering of the IOP and to break acute

attack-- main priorities.

--- Content provided by FirstRanker.com ---


? A. Immediate medical treatment

1. Patient should lie supine to allow the lens to shift

--- Content provided by FirstRanker.com ---

posteriorly.

2. Acetazolamide 500 mg orally(if there is no vomiting).

or I.V Mannitol 20% 1-2 g/kg over 1 hour (rule out

--- Content provided by FirstRanker.com ---


contraindications)

3.Topical

--- Content provided by FirstRanker.com ---

Prednisolone or dexamethasone q.i.d (if AC reaction)

Timolol (if there is no contraindication).

4. Analgesia and emetics as required.

--- Content provided by FirstRanker.com ---


29

? B. Subsequent medical treatment

--- Content provided by FirstRanker.com ---

Pilocarpine 2% q.i.d. to the affected eye and 1% q.i.d. to the

fellow eye.

Topical steroids (prednisolone 1% or dexamethasone 0.1%)

--- Content provided by FirstRanker.com ---


q.i.d. if the eye is acutely inflamed.

Timolol 0.5% b.d.,

--- Content provided by FirstRanker.com ---

and oral acetazolamide 250 mg q.i.d. may be required.

? If the above measures fail:

? Laser iridotomy or iridoplasty after clearing corneal oedema with

--- Content provided by FirstRanker.com ---


glycerol.

? Surgical options in resistant cases include lens extraction,

--- Content provided by FirstRanker.com ---

goniosynechiolysis, trabeculectomy and cycloablation.

30


--- Content provided by FirstRanker.com ---

? Findings suggestive of previous episodes of acute

angle closure glaucoma

? Descemets Membrane folds

--- Content provided by FirstRanker.com ---


? Fine pigment granules on corneal endothelium

? Peripheral anterior synechiae

--- Content provided by FirstRanker.com ---

? Posterior synechiae

? Glaucomflecken

? Sectoral/generalized iris atrophy

--- Content provided by FirstRanker.com ---


? Fixed and semi dilated pupil

? Optic nerve cupping &/or pallor

--- Content provided by FirstRanker.com ---

? Gonioscopy shows narrow angle

or PAS

? Visual field loss

--- Content provided by FirstRanker.com ---


31

Chronic angle closure glaucoma

--- Content provided by FirstRanker.com ---

? Visual Acuity is normal unless damage is

advanced.

? Anterior chamber is shal ower in pupil ary

--- Content provided by FirstRanker.com ---


block than non-pupil ary block.

? Optic nerve signs depend on severity of

--- Content provided by FirstRanker.com ---

damage.

? IOP elevation may be only intermittent.

? Gonioscopic abnormalities-Peripheral

--- Content provided by FirstRanker.com ---


Anterior Synechiae, narrow angle,

pigmentation of Schwalbe's line.

--- Content provided by FirstRanker.com ---

32


Treatment of chronic angle closure

--- Content provided by FirstRanker.com ---

? Medical treatment is similar to that of POAG

? Prostaglandin/Prostamides

Latanoprost, Bimatoprost, Travoprost

--- Content provided by FirstRanker.com ---


? Beta blockers

Timolol maleate, Betaxolol

--- Content provided by FirstRanker.com ---

? Carbonic anhydrase inhibitors

Dorzolamide, Brinzolamide

? Sympathomimetics

--- Content provided by FirstRanker.com ---


Brimonidine, Apraclonidine

? Parasmpathomimetics

--- Content provided by FirstRanker.com ---

Pilocarpine

? Oral carbonic anhydrase inhibitors

Acetazolamide, Methazolamide

--- Content provided by FirstRanker.com ---


33

Treatment of chronic angle closure

--- Content provided by FirstRanker.com ---

? Laser Peripheral Iridotomy (PI) in affected eye

along with Prophylactic PI in fellow eye

34

--- Content provided by FirstRanker.com ---

Laser Peripheral Iridotomy

? Complications of laser therapy
1. Bleeding
2. IOP elevation

--- Content provided by FirstRanker.com ---

3. Iritis
4. Corneal burns
5. Lens opacities
6. Glare and diplopia

--- Content provided by FirstRanker.com ---

35

? Surgical treatment

Trabeculectomy (filtering surgery) is the

--- Content provided by FirstRanker.com ---


surgical procedure of choice

? Success:- 87- 100 % with multiple operations

--- Content provided by FirstRanker.com ---

? Complications:-

? Flat AC, hypotony

? Bleb related infections

--- Content provided by FirstRanker.com ---


? Cyclodialysis

? PATIENTS REQUIRE REGULAR AND LIFE LONG

--- Content provided by FirstRanker.com ---

FOLLOW UP

36
Absolute glaucoma

--- Content provided by FirstRanker.com ---

? Is the final/last stage of PACG

? Clinical features:
? Painful blind eye
?Perilimbal reddish blue zone, due to dilated

--- Content provided by FirstRanker.com ---


anterior ciliary veins

?Cornea gradually becomes hazy, insensitive

--- Content provided by FirstRanker.com ---

with bullous keratopathy and filamentary

keratitis

?Anterior chamber is very shallow/flat

--- Content provided by FirstRanker.com ---


37

Clinical features of absolute glaucoma

--- Content provided by FirstRanker.com ---

? Iris is usually atrophic
?Pupil is fixed and dilated
?Glaucomatous optic atrophy of the optic disc
?High IOP

--- Content provided by FirstRanker.com ---

38
Management of absolute glaucoma

? Cycloablation/destruction of the secretory

--- Content provided by FirstRanker.com ---

ciliary epithelium

q Cyclophotocoagulation
q Cyclocryotherapy
q Cyclodiathermy

--- Content provided by FirstRanker.com ---

? Rarely
? Retrobulbar alcohol injection
? Enucleation of eyeball

39

--- Content provided by FirstRanker.com ---


Complications

? Corneal ulceration
? Staphyloma formation (Ciliary/Equatorial)

--- Content provided by FirstRanker.com ---

? Atrophic bulbi (Shrunken eye)

40
Conclusion

--- Content provided by FirstRanker.com ---

? Primary angle closure glaucoma is a

potentially sight threatening condition,

characterized by occludable anterior chamber

--- Content provided by FirstRanker.com ---


angles.

? Obstruction of aqueous outflow results in rise

--- Content provided by FirstRanker.com ---

of intra ocular pressure, optic nerve damage

and visual field defects.

? Management may include medical, laser

--- Content provided by FirstRanker.com ---


and/or surgical modalities.

41

--- Content provided by FirstRanker.com ---