7. Ocular Manifestations of Systemic Disease Flashcards
(41 cards)
Which diseases of the thyroid may cause eye pathology?
Thyroidtoxicosis (Excessive Thyroid secretion) Graves Disease (AI, IgG binds to TSH receptors, T3/4 secretion).
What are the systemic presentations of hyperthyroidism?
Diffuse thyroid enlargement Fine hand tremor Finger clubbing Pretibial myxoedema Tachycardia Atrial fibrilation
Describe the pathophysiology of the ocular manifestations of Thyroid Eye Disease?
It is an organ-specific autoimmune reaction.
Inflammation of extraoccular muscles.
Enlargement. Up to 8x.
Then they degenerate and become fibrosed = Restrictive myopathy & diplopia
Inflammatory Cellular Infiltration = Increases volume of orbital contents = Elevated IOP
What are the clinical ocular manifestations of TED?
Soft tissue involvement Lid retraction Proptosis Optic neuropathy Restrictive myopathy
What are the signs and symptoms of soft tissue involvement in TED?
SIGNS
Grittiness, lacrimation, retrobulbar discomfort
SYMPTOMS
Epibulbar hyperaemia (Red)
Periorbital swelling (Bags below/above eyes)
Chemosis (oedema of the conjunctiva)
What are the the signs of Lid Retraction?
- Dalrymple sign: lid retaraction in primary position
- Kocher sign: frightened appearance on attentive fixation
- Von Graefe sign: retarded descent of upper eye lid on downgaze-lid lag
How is proptosis categorised?
Axial
Unilateral or bilateral
Symmetrical or asymmetrical
What are the possible complications of proptosis?
Incomplete lid closure exposure keratitis or corneal ulceration
How is proptosis managed?
Systemic steroid used in rapidly, progressive & painful
Radiotherapy
Combined therapy
Surgical decompression
What is restrictive myopathy?
Ocular motility is restricted by inflammatory oedema & later by fibrosis
What is the Tx for restrictive myopathy?
Treatment is by surgery, if there is diplopia in primary or reading position
What is Optic Neuropathy?
Uncommon but serious complication
There is optic n. compression at the orbital apex by the enlarged recti
How does optic neuropathy present?
Impairment of central vision
Decreased VA, RAPD, colour vision desaturation Reduced light brightness appreciation
VF defect
What is the treatment for optic neuropathy?
Systemic steroid
Orbital decompression
What is Myasthenia Gravis?
Autoimmune disease
Antibodies mediates damage to acetylcholine receptors in striated muscle = impairment of neuromuscular conduction
There is weakness & fatigability of skeletal musculature
What are the systemic manifestations of Myasthenia Gravis?
Usually in the third decade Mostly with ptosis & diplopia Painless fatigue by exercise Worse towards the end of the day Difficult swallowing Difficult breathing is rare but serious
What are the ocular manifestations of Myasthenia Gravis?
OCULAR MYASTHENIA
Ptosis is insidious, bilateral & asymmetrical
Worse by the end of the day
Worse on prolong upgaze
Positive ice test: ptosis improves if an ice pack placed over the eye lids for 2 min.
Diplopia
What tests should be positive in myasthenia gravis?
Edrophonium ( Tensilon) test
Ice Test
Describe the Edrophoium Test
Edrophonium is a short acting anticholinesterase agent
It increases the acetylcholine available at the neuromuscular junction
In myasthenia there would be improvement of symptoms & signs
Uncommon complication: bradycardia
Method:
a. Objective baseline measurements are made for ptosis & diplopia b. IV atropine to minimize the side effect c. IV edrophonium d. Repeat ptosis & diplopia measurements
What are the Tx options for myasthenia gravis?
Anticholinesterase drugs (pyridostigmine, neostigmine) Steroid Immunosuppressive drugs Plasma exchange Intravenous immunoglobline
Autoimmune inflammation & destruction of lacrimal & salivary glands?
Sjogren’s Syndrome
Distinguish between primary and secondary sjogrens disease? Which is more common in females?
Classified as Primary when it exists in isolation
Secondary when associated with other disease e.g. Rh. arthritis, SLE, systemic sclerosis
The primary one is more common in females
How does Sjogren Syndrome typically present?
Dryness, grittiness of the eyes
Posterior blepharitis (inflammation of the eyelids)
Reduced tear secretion
Ankylosing spondylitis = Rieter syndrome associated with anterior uveitis
Rheumatoid arthritis = Wegener granulomatosis with scleritis, peripheral corneal ulceration
What is the hallmark of hypertensive retinopathy
Optic disc swelling is the hallmark of malignant hypertension.
Rare, may occur as the result of an acute hypertensive crisis (accelerated hypertension) in young adult.
Exudative retinal detachment, sometimes bilateral