Intraocular Inflammation Flashcards
what are the 3 components of the vascular tunic of the eye?
- iris
- ciliary body
- choroid
what 2 things make up the anterior uvea?
- iris
- ciliary body
what are the 3 components of the iris?
- posterior pigment epithelium
- stroma
- muscles – dilator, sphinctor
which of the following statements if FALSE about the function of the uvea?
A. vitreous humor dynamics (CB – produce and filtrate)
B. removes waste
C. absorbs light (pigment of iris)
D. controls light (through pupil)
E. blood aqueous barrier
A. vitreous humor dynamics (CB – produce and filtrate)
its actually AQUEOUS humor production by the ciliary processes and then AH drainage by the iridocorneal angle.
__________ is inflammation of any aspect of the uveal tract.
Bonus if you know the 3 types
Uveitis
Anterior Uveitis= iris + CB, Posterior Uveitis=choroid, Panuveitis= all 3
What are the clinical signs associated with uveitis?
- blepharospasm
- episcleral injection (congestion of the vessels)
- ciliary flush (360 degree corneal vascularization)
- corneal edema (build up in stromal layer)
- miosis
- synechiae (adherence of iris to cornea or lens)
- aqueous flare (release of protein into aqueous – breakdown of BAB)
- hyphema
- hypopyon
- keratic precipitates
- rubiosis iridis (congestion of iridial vasculature)
- hypotony (low IOP, <15)
What are the complications that can arise from uveitis?
- synechiae
- glaucoma
- iris bombe
- cataracts
- lens instability
- retinal detachment
- phthisis bulbi
How can uveitis cause glaucoma? (3 mechanisms)
- obstruction of the iridocorneal angle by inflammatory debris
- pre-irida fibrovascular membrane
- iris bombe + peripheral anterior synechiae
T/F: there is limited regeneration of the uveal tissue
true
What 3 events generate inflammation?
- release of chemical mediators by cells
- presence of certain pathogen-associated molecules
- release of pro-inflammatory molecules by immune cells
___________ is characterized by 360 degree vascularization on the cornea and is present in cases of INTRAocular disease.
ciliary flush
_________ is fluid build-up within the stroma (middle layer of the cornea) and occurs due to the altered function of the corneal endothelium.
corneal edema
when a pt has uveitis, aqeous flare can occur; when this occurs, the AH is not healthy enough to nourish the corneal endothelium. This leads to fluid build up d/t alterations of the Na-K pumps within the cornea that typically remove the fluid.
____________ is pupillary constriction that is caused by painful spasms of the ciliary body musculature.
miosis
___________ is adherence of the iris to the cornea (anterior) or lens (posterior) which is lead by inflammatory cells, fibrin, and fibroblasts.
synechiae
this is a problem because if the iris is stuck to the lens, then light cannot be regulated and the pupil will not move as it should. This will lead to pupillary block. Secondary glaucoma can occur.
____________ is protein in the aqueous humor (anterior chamber) due to a disruption of the blood aqueous barrier.
aqueous flare
it appears as a hazy anterior chamber.
__________ is characterized by WBCs in the aqueous humor (anterior chamber), particularly PMNs. Usually appears ventrally-dependent.
hypopyon
________ is characterized by RBCs in the aqueous humor (anterior chamber)
hyphema
___________ is inflammatory cells, fibrin, and iris pigment adhered to the endothelium (inner most layer of cornea)
keratic precipitates
_________ is injection of the iridial blood vessels.
rubiosis irides
what is the medical term for LOW intraocular pressure?
What is the pathophysiology behind low intraocular pressure?
hypotony
The CB is responsible for AH production, so if the eye is inflammed (full of protein, WBCs, etc.), then the CB will not get nutrition from the AH –> CB activity will decrease –> AH production will decrease –> decreased IOP.
another theory: uveitis –> increased permeability of BAB –> fluid goes out of eye –> decreased IOP.
what are 3 common exam clues that lead to uveitis?
- miosis – spasm of CB muscles and pupillary sphincter
- low IOP (decreased prod of AH by CB)
- aqueous flare, hypopyon, and/or hyphema (d/t breakdown of BAB)
what are 3 primary ocular disease causes of uveitis?
- cataracts
- lens rupture
- corneal ulcer
T/F: uveitis in many cases can be idiopathic
true
What are the 2 types of lens-induced uveitis in dogs and the difference between them?
- Phacolytic uveitis – soluble lens protein slowly leaks through an intact lens capsule (ex. cataract)
- Phacoclastic – sudden exposure of intact lens protein (Ex. trauma causing lens capsule tear)
