Eye 2 Flashcards
Thyroid Orbitopathy AKA Thyroid Eye Disease
General
Usually an immune-mediated disorder
most commonly presents in association with hyperthyroidism in Graves disease but sometimes seen in euthyroid or hypothyroid pts.
Orbitopathy may precede the actual thyroid disease
female-to-male ratio of 4:1 and a peak in the fourth to fifth decade
It is the most common cause of bilateral or unilateral proptosis
Bilateral involvement is the most frequent presentation
deposition of mucopolysaccharides, namely hyaluronic acid, within the extraocular muscles. Results in a classic imaging appearance of fusiform muscle enlargement with sparing of the muscular tendon
Uveitis
S/Sx and complications
Emergency inflammation of uveal tract (choroid, ciliary body, iris)
Can cause blindness
Painful, red, photophobia- these are less common when posterior uveitis but posterior is very uncommon anyway
Distorted/blurred vision
Uveitis
General
Sudden onset with no easy cause to explain symptoms
Usually acute and less than 3 months duration but can be recurrent or chronic
Can be unilateral or bilateral
Easy to confuse with glaucoma
Sometimes occurs in patients with adult RA/JRA, sarcoidosis, MS, syphilis, Lyme dz, CMV, HSV, TB, ankylosing spondylitis, and other inflammatory diseases
Sometimes can be drug induced (especially with certain antibiotics and antivirals)
Uveitis
types
- Anterior: anterior chamber structures
- Posterior: retina, choroid
- Intermediate= vitreous body only;
4.Panuveitis= EVERYTHING
Uveitis
PE
Physical Exam:
Small or constricted pupil
Pupil reacts poorly to light (iris is stuck to anterior lens capsule)
Iris sometimes difficult to see (because of corneal edema and protein in aqueous humor)
Redness
Photophobia
WBCs settled in the bottom of the anterior chamber
Sometimes decreased IOP
Uveitis
Slit lamp findings
Uveitis
Tx
Needs immediate referral to ophthalmology
Can be exacerbated if given drugs for treating glaucoma
Usually given steroids first but this can cause other diseases on the differential list to worsen
Uveitis
Complications
19% to 60% of patients have visual loss (depending on population)
Cyst-like formations on/in macula
Glaucoma can be caused by disease AND treatment
Cataracts can be caused by using steroids for treatment
Episcleritis
general and causes
Inflammation of the episclera (thin layer of vascular elastic tissue between the sclera and conjunctiva)
Pretty rare
Most common in 40s
Usually idiopathic but can happen with trauma, vasculitis and collagen-vascular diseases (marfan)
Episcleritis
PE
Red, vascular injection of conjunctiva with enlarged blood vessels beneath the conjunctiva
Pain is mild and only in area of inflammation
Can be diffuse or nodular inflammation
Episcleritis
Tx
Refer to ophthalmology
Warm compresses
Steroids (topical)
NSAID drops if worried about glaucoma
Oral NSAIDs
Nystagmus
General
Involuntary rhythmic eye motion/oscillation
Results from dysfunction in vestibular system, brainstem, or cerebellum
MANY types, next few slides are only a few examples
Vestibular nystagmus
patho
Vestibular nystagmus results from dysfunction of the labyrinth (Ménière’s disease), vestibular nerve, or vestibular nucleus in the brainstem.
vestibular nystagmus
S/Sx
nausea and vertigo
Possibly associated tinnitus and hearing loss
*Sudden shifts in head position may provoke or exacerbate symptoms.
Jerk Nystagmus
general
This is characterized by a slow drift off the target, followed by a fast corrective movement. Jerk nystagmus can be downbeat, upbeat, horizontal (left or right), and torsional. Some patients will be oblivious to their nystagmus. Others will complain of blurred vision or a subjective to-and-fro movement of the environment (oscillopsia) corresponding to the nystagmus.
Up/Downbeat nystagmus
General
Downbeat nystagmus results from lesions near the craniocervical junction (Chiari malformation, basilar invagination). It also has been reported in brainstem or cerebellar stroke, lithium or anticonvulsant intoxication, alcoholism, and multiple sclerosis.
Upbeat nystagmus is associated with damage to the pontine tegmentum from stroke, demyelination, or tumor.
Gaze evoked nystagmus
general
When the eyes are held eccentrically in the orbits, they have a natural tendency to drift back to primary position. The subject compensates by making a correction to maintain the deviated eye position. Many normal patients have mild gaze-evoked nystagmus. Exaggerated gaze-evoked nystagmus can be induced by drugs (sedatives, anticonvulsants, alcohol); muscle paresis; myasthenia gravis; demyelinating disease; and cerebellopontine angle, brainstem, and cerebellar lesions.
Strabismus
general
visual axes of the eyes are not aligned
misalignment may be constant or intermittent, and it may vary depending on the gaze direction
2% of population
Most common in childhood
caused by problems with eye muscles, the nerves that transmit information to the muscles, or the control center in the brain that directs eye movements
strabismus
RF
Risk factors for developing strabismus include:
Family history of strabismus.
Refractive error. People who have a significant amount of uncorrected farsightedness (hyperopia) may develop strabismus because of the additional eye focusing they must do to keep objects clear.
Medical conditions. Down syndrome, cerebral palsy & those who have suffered a stroke or head injury are at a higher risk
Strabismus
Emergent causes
Emergent causes can be orbital fractures, cellulitis, tumors (primary or metastatic), meningitis, or elevated IOP
Strabismus