Thyroid Eye Disease/Thyroid Orbitopathy Flashcards
What is it?
Autoimmune, inflammation of orbital tissue in patients with thyroid disease.
What causes this?
Stimulation of orbital fibroblasts that up regulate the synthesis of GAGs that deposit in orbital tissues leading to congestion and edema.
These fibroblasts can differentiate into adipocytes or my-fibroblasts that lead to fat accumulation and muscle enlargement.
90% of TED are associated with
Graves disease. Also associated with Hyperthryoidism, hypothyroidism, and Hashimoto’s
Demographics
Women 40-60 years
Laterality
Bilateral
Symptoms
Dry eye due to exposure (lagophthalmos) Elevation of upper lid, above limbus. Bulging eyes Eyelid swelling Double vision Pain on eye movement
Sign
Upper eyelid retraction (Dalrymple’s sign, lagophthalmos, or temporal flare)
Exophthalmos (proptosis, globe protrudes)
Periorbital edema and erythema
Conj injection and chemosis (at rectus muscle insertion)
Exposure keratopahy due to lagophthalmos and exophthalmos.
Superior limbic keratoconjunctivitis. Inflammation of the superior limbus (K, bulbar and tarsal conj)
Von Grafe’s sign (Dynamic)
Eyelid lag (static)
pain on EOMs
3 signs that go along with upper eyelid retraction
- Dalrymple’s sign. Widening of the palpebral fissure with superior scleral show.
- Lagophthalmos. Inability to close the eyes completely.
- Temporal flare. Elevation of the temporal upper eyelid to its normal anatomical location.
Where will I likely see conj injection and chemosis
More pronounced at site of rectus muscle insertion
Exposure keratopathy
Cornea damage that occurs from prolonged exposure to the outside environment. Due to lapopthalmos and exophthalmos.
Superior limbic keratoconjunctivitis
Inflammation of the superior limbus, cornea, bulbar and tarsal conj
Von Grafe’s sign
Delayed descent of the upper eyelid during downgaze. Dynamic finding.
Pt looks down- upper eyelid is slower.
Eyelid lag
Upper eyelid is higher than normal when the eye is in downgaze. Static finding.
What two recti muscles are most commonly affected? leading to __
inferior and medial. Leading to hypotropia and esotropia.
Complications
Compression of the globe or ON.
Compressive optic neuropathy occurs in __% of cases
5
** Why you should dilate to look at ON
Management
Always dilate to look at ON Topical lubrication Dry eye tx Eyelid taping or patching qhs- sleep mask. Cold compress qam and head elevation qhs sodium restriction prism for diplopia. **Smoking cessation.
Smokers with graves disease are __x more likely to develop TED compared to nonsmokers.
7x. Must talk to them about stopping.
How to manage moderate to severe cases of compressive optic neuropathy?
Oral or IV steroid.
Orbital radiotherapy.
Orbital decompression surgery.
When to order orbital CT or MRI?
Severe congestive orbitopthaly or optic neuropathy or atypical cases. Unilateral proptosis or bilateral proptosis without upper eyelid retraction.
Exophthalmometry
- What is it
- What are normal limits
Monitors exophthalmos.
12-20mm whites
12-24 mm blacks
Within 2 mm between the eyes
What is the most common cause of orbital disease in adults?
TED
What is the most common presenting sign of TED.
2nd most common?
Upper eyelid retraction is most common. 2nd most is exophthalmos.
What causes upper eyelid retraction?
Increased sympathetic tone acting on muller’s muscle, contraction of the levator, proptosis and/or scarring between the levator and lacrimal gland.
Divided into which two phases?
Active phase (progressive)
- Lasts 1-3 years.
- Symptoms wax and wane
- 5-10% risk of recurrence.
Stable phase.
-Spontaneous resolution of the active phase.
What measuring system is used to classify severity
Wener’s NOSPECS
Class 0- no signs or symptoms
Class 6- Sight loss due to ON involvement
When can surgery be advised?
Until the thyroid state is maintained and the TED has been in the stable phase for at least 6-9 months.
Exceptions include vision loss from compressive optic neuropathy or exposure keratopathy.
What % of patients with TED undergo surgical intervention?
20%
Does TED follow the associated thyroid disfunction?
No. may occur months-years before or after thyroid disfunction.
What other disease may occur in a minority of patients?
Myasthenia Gravis.
Fluctuating diplopia and ptosis that is worse at the end of the day.
