Pathophysiology of angle-closure of glaucoma - PACG

Question 1

What does PACG involve?

Answer 1

• mechanical obstruction aq humour outflow through trabecular meshwork by peripheral iris

Question 2

What are two major mechanisms of trabecular meshwork obstruction by peripheral iris

Answer 2

1. pupillary block

2. iris plateau - abnormality of iris

Question 3

What is pupillary block?

Answer 3

1. complete/functional apposition central irisi to anterior lens = mild dilation pupil
2. trapped aq humour in posterior chamber = increase pressure behind iris
3. cause peripheral iris bow forward + obstruct trabecular meshwork

Question 4

What is plateau iris?

Answer 4

1. anterior displacement of peripheral iris
2. caused anterioul positioned ciliary process
3. peripheral iris bunches as eye dilates

Question 5

What do pupillaroy block + plateau iris cause?

Answer 5

1. occlusion aq humour outflow

2. IOP elevation –> vision loss in hrs -dayss

Question 6

How is the degree of iridotrabecular contact - angle closure assesed?

Answer 6

• visulaize anatomy iridocorneal angle

- examine by gonioscopy