Angle Closure Spectrum

1. FHx of angle closure

2. older age

3. female

4. Chinese, Vietnamese, Pakistani, Inuit descent

what are the demographic risk factors for ACG?

1. hyperopia

2. shallow peripheral AC depth

3. shallow central anterior chamber depth

4. steep corneal curvature

5. thick crystalline lens

6. short axial length

7. anterior position of CB (plateau iris)

8. anterior lens position

what are the ocular risk factors for ACG?

primary angle-closure suspect

180deg or more of iridotrabecular contact (occludable angle), normal IOP, & no optic nerve damage, normal VF

primary angle closure

180 deg or more of iridotrabecular contact (occludable angle) w/ peripheral anterior synechiae or elevated IOP but no optic neuropathy, normal VF

primary angle closure glaucoma

180 deg or more iridotrabecular contact w/ PAS, elevated IOP, & optic neuropathy, VF abnormalities

acute angle closure crisis

occluded angle w/ symptomatic high IOP

plateau iris configuration

narrow angle due to an anteriorly positioned CB, w/ deep central AC

plateau iris syndrome

narrow angle due to an anteriorly positioned CB, w/ deep central anterior chamber, & any iridotrabecular contact persisting after patent peripheral iridotomy

peripheral iris prevents aqueous from reaching the TM

why does IOP become elevated in angle closure?

pupillary block

impedance to aqueous flow from the posterior to the anterior chamber through the pupil, causes pressure in the posterior chamber to become higher than that in the anterior chamber, pushing the peripheral iris forward & narrowing the angle (angle closure)

1. pupillary block

2. plateau iris

3. retrolenticular mechanisms

what are the mechanism classifications of angle closure?

pupillary block

what is the most common form of angle closure?

plateau iris

anteriorly positioned ciliary processes push the iris forward

ciliary block, posterior aqueous diversion, aqueous misdirection, malignant glaucoma

what are the retrolenticular mechanisms?

1. pupillary block

2. without pupillary block

3. anterior mechanisms

what are the angle closure configuration classifications?

1. lens related mechanisms

2. phakic IOLs

3. uveitis

what are some “pupillary block” causes of angle closure?

1. plateau iris configuration/syndrome

2. aqueous misdirection syndrome, ciliary block

3. uveal edema

4. tumors

5. cysts

what are some “without pupillary block” causes of angle closure?

1. ICE

2. PPMD

3. NVG

4. uveitis

what are some “anterior mechanism "causes of angle closure?

plateau iris

• due to a large or anteriorly positioned CB

• iris root is short & inserted anteriorly on ciliary face, so that the angle is shallow & narrow, w/ a sharp drop-off of the peripheral iris at the inner aspect of the angle

• iris surface appears flat & the AC is of relatively normal depth

• double hump sign on gonioscopy

• most common in younger women

• tx: peripheral iridoplasty/cataract surgery

plateau iris syndrome

refers to the development of angle closure, either spontaneously or after pupillary dilation in eye w/ plateau iris configuration despite the presence of patent LPI

plateau iris configuration

• deep axial anterior chamber

• flat iris plane

• steeply rising peripheral iris

• anterior positioned ciliary process

• narrow ciliary sulcus

latent/suspect

• no symptoms

• narrow Van Herick angle, shallow AC depth, iris bombe

• occludable angle w/ no pigmented TM visible on gonio

• clinical course:

  • IOP may remain normal

  • acute or subacute angle closure may develop

  • chronic angle closure

• tx:

  • consider LPI

subacute angle closure

• symptoms:

  • halos

  • smoking vision

  • frontal HAs by 1-2hrs then resolution

• occludable angles on gonioscopy

• clinical course:

  • acute attack or chronic angle closure

• tx:

  • LPI ASAP

acute angle closure

• sight threatening emergency

• symptoms:

  • severe pain

  • HA

  • halos

  • nausea

  • vomiting

  • sweating

  • blurry vision

• signs:

  • ciliary flush

  • corneal edema

  • shallow angle

  • cells & flare

  • vertical oval fixed mid-dilated pupil

  • convex iris

  • iris blood vessels congested

  • IOP elevated (50-100mmHg)

  • disc edema

chronic angle closure

• often no symptoms

• varying degrees of angle closure w/ creeping PAS that starts superiorly

• PAS from subacute attacks

• signs of POAG

• tx:

  • LPI

  • medical

  • trabeculectomy?

postcongestive angle closure

• postsurgical LPI - normal IOP, elevated IOP w/ trabecular damage or PAS > 180; medical or surgical management

• signs:

  • iris atrophy & spiraling

  • glaukomfleckin lens opacities

  • IOPs normal or still elevated

malignant or aqueous misdirection glaucoma

• occurs in phakic eye after intraocular surgery w/o lens extraction or narrow angles w/ cataract surgery

• occurs in eyes which were partially closed preoperatively

• shallow or flat AC w/ increased IOP after surgery

malignant glaucoma in aphakia

• occurs w/ aphakia w/ intact vitreous face

• aqueous misdirected behind vitreous

• vitreous pushes forward, narrowing the AC

1. decreasing IOP

2. decrease inflammation

3. rapid breaking of the attack

4. clear cornea

5. protect optic nerve

6. open the angle

7. prevent PAS

what are the goals for managing acute angle closure?

1. miotics

2. beta blockers

3. alpha adrenergic agonists

4. topical steroids

5. CAIs

6. oral/IV hyperosmotic agents

7. corneal indentation

8. LPI (laser peripheral gonioplasty/iridoplasty, surgical iredectomy, parecentesis, cataract surgery, trabeculectomy, goniosynechialysis)

what are the tx options for acute angle closure?

laser peripheral iridotomy

• reestablishes communication b/t the posterior & anterior chamber

• indications: AAC, prophylactic in fellow eye, intermittent & chronic AC, possibly occludable angles

Yag

is argon or Yag preferred for LPI?

T

T/F: LPI is contraindicated if there is corneal edema & severe iris congestion

we were overdoing it on the prophylactic LPIs

what did the ZAP trial tell us?

more severe cataracts, higher IOP

the ZAP trial found that LPI eyes had a _________

1. higher IOP

2. shallower limbal anterior chamber depth

3. greater central anterior chamber depth

what did the ZAP trial find were risk factors for greater likelihood of reaching endpoint in the control group?

1. higher IOP

2. shallower limbal anterior chamber depth

3. less IOP elevation after being in a dark room

what risk factors did the ZAP trial find for post LPI eyes having PAC?

examined the effectiveness of early lens extraction for the tx of primary angle closure glaucoma

what was the goal of the EAGLE study?

10

___% of acute angle closure attacks present w/ bilateral disease

50

__% of acute angle closure pts have an acute attack in the contralateral eye if untreated over a 5y period

days

contralateral involvement in an acute angle closure can occur within ____

1. LPI

2. miotic agents

3. peripheral gonioplasty

4. argon laser peripheral iridoplasty

5. clear lens extraction/cataract surgery

what are the tx options for plateau iris syndrome?

1. LPI

2. cataract surgery

3. goniosynechialysis

4. trabeculectomy

what are the options for PACG management?

1. cycloplegic

2. topical/systemic steroids

3. aqueous humor suppressants

4. NO MIOTICS

what are the tx options for a systemic topamax AAC attack?

T

T/F: if cornea is too edematous, perform gonio on uninvolved eye, if the angle is not occludable then this is prob not AACG

F (must r/o plateau iris)

T/F: the presence of patent LPI means the patient is always safe to be dilated

narrow angle, no structures evident

PAS

pupillary block

double hump

acute angle closure glaucoma

glaukomflecken

pupil block