Iris Disorders Flashcards
what iris disorder is caused by abnormal adhesions of the anterior surface of the peripheral iris to the trabecular meshwork & corneal endothelium?
peripheral anterior synechiae
these can all cause which iris disorder? which 2 are most common? - anterior uveitis - narrow anatomical angles - iridocorneal endothelial syndrome - iridocorneal dysgenesis
peripheral anterior synechiae
- anterior uveitis & narrow anatomical angles most common
what procedures can be used to diagnose peripheral anterior synechiae? which one is used primarily?
- gonioscopy (preferred)
- anterior segment OCT
what complications can arise from peripheral anterior synechiae?
elevated IOP & angle closure glaucoma
what is the management for peripheral anterior synechiae?
- treat underlying cause: uveitis, narrow angles
- IOP lowering medications if necessary
what iris disorder is caused by adhesion of posterior iris surface to the anterior lens capsule? where does this adhesion occur?
posterior synechiae
- occurs at pupillary margin where they’re the closest to each other
what can cause posterior synechiae?
- anterior uveitis
- trauma
what is the management for posterior synechiae?
- manage underlying condition
- 10% phenylephrine to break synechiae
what is a complication of posterior synechiae that is usually due to chronic/recurrent uveitis?
seclusion papillae → 360 degrees of iris-lens adhesion
in seclusion papillae, what happens to IOP?
significant IOP elevation
what iris disorder is caused by the absence of pigmentation in the posterior epithelial layer of the iris?
iris transillumination defect
these can all cause which iris disorder?
- pigment dispersion syndrome
- pseudoexfoliation syndrome
- HSV/HZV uveitis
- ICE syndromes
- albinism
- Fuch’s heterochromic iridocyclitis
- trauma
- surgery
iris transillumination defects
what are the two most common causes of rubeosis iridis?
CRVO & proliferative diabetic retinopathy
what is also known as neovascularization of the iris?
rubeosis iridis
how do you manage rubeosis iridis?
- treat underlying disease
- treat elevated IOP from neovascularization of the angle
what iris disorder presents as a difference in color between the two irides?
heterochromia iridis
these can all cause which iris disorder?
- congenital Horner’s syndrome
- Fuch’s heterochromic iridocyclitis
- chronic anterior uveitis
- trauma
- intraocular foreign body
heterochromia iridis
how do you manage heterochromia iridis?
treat underlying condition if present
which iris disorder is caused by the failure of the embryonic fissure to close during the 5th week of gestation?
iris coloboma
typical colobomas are located where? results in what kind of pupil?
inferonasal quadrant → “keyhole pupil”
are colobomas unilateral or bilateral?
can be either or
how do you manage iris coloboma?
- cosmetic contact lenses
which iris disorder is caused by remnants of tunica vasculosa lentis (vascular network that surrounds lens during embryogenesis)?
persistent pupillary membrane
are persistant pupillary membranes progressive or non-progressive? what impact do they have on VA?
non-progressive & usually has no effect on VA