Lec. 10: Angle Closure Glaucoma

What factors can not precipitate angle closure?

Bright illumination

What is the most common form of Primary angle closure?

Pupillary angle closure

Name the symptoms that does not belong to angle closure?

Flashes of light

Name the signs that does not belong to angle closure?

Conjunctival follicles 

What anterior segment signs can indicate a prior attack of angle closure?

All of the above

What causes the presence of cells and flare during angle closure?

When the blood aqueous barrier breaks, proteins get into the anterior chamber which makes it sticky

What is the IOP usually during an acute angle closure?

Exceeds 40 mmHg

What leads to the symptom of halos during angle closure?

Corneal edema scatters light and creates colored halos 

At what pressure does corneal edema occur usually during angle closure?

Very high 50mmHg or higher 

What causes pupil to be unreactive during angle closure?

1. Paralysis & ischemia of the pupillary sphincter which is caused by the increase in IOP causes a fixed mid dilated pupil

2. The pupillary sphincter is unable to contract

What leads to ciliary conjunctival congestion during angle closure?

1. Venous congestion: this occurs when IOP exceeds that of the episcleral veins

2. Iris blood vessels become dilated and also the veins in the conj give the pt a painful red eye

What causes iris atrophy after an attack of angle closure?

1. The abrupt increase in IOP causes an interruption of the arterial supply to the iris which results in ischemia

2. This causes damage to the iris leaving behind patches of stromal atrophy

What is the reason for nausea and vomiting that accompanies an angle closure attack?

High IOP triggers the trigeminal-vagal reflex which results in nausea & vomiting 

What features of anterior chamber facilitate pupillary block?

All

What anatomical of ocular structure does not facilitate angle closure?

Berger's space

Describe plateau iris

All

What is not a mechanisms that increase iridotrabecular contact?

Thinner iris

What are risks with plateau iris and dilation?

They may have angle closure when the pupil is dilated or The angle can close suddenly bc the peripheral iris is already crowded

Discuss medical management of a patient with acute angle closure?

Maybe all of the above

What are best modality and therapies for angle closure?

• Acetazolamide 500 mg IV

• IV mannitol 

What is the protocol for lowering IOP in office medically?

ABC Protocol

• Alpha 2 agonist - brimondine

• Beta blocker - timolol or betaxolol

• Carbonic anhydrase inhibitor - dorzolamide

What is the major outcome and recommendation from the ZAP trail?

Widespread prophylactic laser for angle closure suspects is not recommended

What take home medications are needed for the patient to control pressure and decrease inflammation with angle closure?

1. Prednisolone acetate 1% every hour-6 hours

   1. Approx every 3 hours

2. Acetazolamide 500 mg sequel BID

3. Alpha agonist or beta blocker BID

4. Pilocarpine 2% QID

What is the major outcome and recommendation from the EAGLE trial?

• Lens extraction after primary angle closure glaucoma leads to:

  • Better quality of life

  • Lowering of IOP

  • Less need for glaucoma surgery than with standard care

• Standard care: laser iridotomy & meds