THYROID EYE DISEASE

GRAVE’S OPTHALMOPATHY

INTRODUCTION

INTRODUCTION--THYROID EYE DISEASE

• Seen in 25 – 50% of graves disease.• GRAVES DISEASE also known as BASEDOW’S

DISEASE is an autoimmune disorder that usually presents in 3rd to 4th decade of life, affects women more than men, characterized by a triad of features:

• Hyperthyroidism• Diffuse thyroid enlargement• Opthalmopathy

=HYPERTHYROIDISM

=DIFFUSE THYROID ENLARGEMENT

=OPTHLMOPATHY

INTRODUCTION -- TED

• Thyroid eye disease (TED) may occur in the absence of clinical and biochemical evidence of thyroid dysfunction.

• The occurrence of signs of graves disease in a patient who is not clinically hyperthyroid is referred to as euthyroid or ophthalmic graves disease.

• Eye disease may be the first presenting sign of graves disease.

ETIOLOGY

THYROID EYE DISEASE

ETIOLOGY

==GENETIC FACTOR ASSOCIATION: -- HLA DR3, CTLA-4, PTPN22( a T- cell regulatory gene).

==RADIOACTIVE THYROID: Thyroid ablation with orally

ingested radioactive iodine-131 may excerbate

thyroid associated orbitopathy compared with anti-thyroid drugs and surgical ablation.

==AUTOIMMUNE DISEASE ASSOCIATION:

-- Myasthenia gravis, addison disease.

•STRONG ASSOCIATION OF

THYROID EYE DISEASE WITH

SMOKING

PATHOGENESIS

PATHOGENESIS

• This involves an organ specific autoimmune reaction in which a humoral agent (IgG antibody) produces the following changes:

• INFLAMMATION OF EXTRAOCULAR MUSCLES

• INFLAMMATORY CELLULAR INFILTRATION

PATHOGENESIS:INFLAMMATION OF EXTRAOCULAR MUSCLES

• Pleomorphic cellular infiltration, increased secretion of glycosaminoglycans,osmotic retention of water.

• Muscles become enlarge( 8 times their normal size, may compress optic nerve).

• Subsequent degeneration of muscle fibers eventually leads to fibrosis

• Restrictive myopathy and diplopia.

HISTOLOGICAL PICTURE SHOWING ROUND CELL INFILTRATION OF EXTRA OCULAR MUSCLES IN

THYROID EYE DISEASE

PATHOGENESIS:INFLAMMATORY CELLULAR INFILTRATION

Infiltration with lymphocytes, plasma cells, macrophages & mast cells of interstitial fluid, orbital fat & lacrimal glands

Increase in volume of orbital contents & secondary elevation of intraorbital pressure.

Accumulation of glycosaminoglycans & retention of fluid.

Secondary elevation of intraorbital pressure.

CLINICAL MANIFESTATIONS

CLINICAL MANIFESTATION5 main clinical manifestations of TED are:

1… SOFT TISSUE INVOLVEMENT

(PERIORBITAL & LID SWELLING, CONJUCTIVAL HYPEREMIA.

2...LID RETRACTION3…PROPTOSIS (PASSIVE OR MECHANICAL

PROTRUSION OF EYE BALL)

4…OPTIC NEUROPATHY (SERIOUS COMPLICATION –

COMPRESSION OF OPTIC NERVE MAY LEAD TO VISUAL IMPAIREMENT)

5…RESTRICTIVE MYOPATHY

(OCULAR MOTILTY IS REDUCED INITIALLY BY INFLAMMATORY EDEMA & LATER BY FIBROSIS)

SYMPTOMS

OCULAR SYMTOMS• DRY EYES• BULGING EYES• DIPLOPIA• VISUAL LOSS• OCULAR PRESSURE OR PAIN• PHOTOPHOBIA• LACRIMATION

SYSTEMIC SYMPTOMS• TACHYCARDIA• NERVOUSNESS• HEAT INTOLERANCE• INCRESE SWEATING• WEIGHT LOSS• IRRATIBILITY• SKELETAL MUSCLE

WEAKNESS

OCULAR SIGNS• VIGOUROUX SIGN( eyelid fullness)• DALRYMPLE SIGN( lid retraction in

primary gaze)• von GRAEFE SIGN( retarted descent

of upper lid at downward gaze• STELLWAG SIGN

( incomplete & infrequent blinking)• GROVE SIGN( resistance to pulling

down the retracted upper lid)• JOFFROY SIGN ( abscent creases in

forehead on sup. gaze)• MOBIUS SIGN( poor convergence)• BALLET SIGN ( restriction of one or

more extra ocular movements)• KOCHER SIGN ( staring & frightened

appearance of eyes)

• PROPTOSIS ( eyes protude beyond orbit…unilateral or bilateral)

• Exophthlmos (appearance of protuding eyes)

• Conjuctival edema• Corneal ulceration• Visual impairement• Visual field defects• Papilloedema• Loss of colour vision• Opthlmoplegia• Optic disc usually normal

SEVERE BILATERAL PROPTOSIS & LID RETRACTION IN THYROID EYE DISEASE

PERIORBITAL SWELLING IN THYROID EYE DISEASE

LEFT EYE SHOW LID RETRACTION &MILD PROPTOSIS

von GRAEFE SIGN( RIGHT EYE)

KOCHER SIGN

RESTRICTED LEFT EYE ABDUCTION

SYSTEMIC SIGNS

• FAST/ IRREGULAR PULSE

• WARM MOIST SKIN• FINE TREMOR• PALMER ERYTHEMA• HAIR LOSS

DIFFERENTIAL DIAGNOSIS

DIFFERENTIAL DIAGNOSIS

• ORBITAL CELLULITIS: Onset of proptosis is earlier & patient has other evidence of infection. (fever)

• IDIOPATHIC ORBITAL INFLAMMATORY DISEASE: More painful than thyroid eye disease.

• OTHER CAUSES OF THICKENED MUSCLES: sarcoidosis, amyloid, acromegaly.

INVESTIGATIONS

INVESTIGATIONS

NON- SPECIFIC• ROUTINE BLOOD PICTURE.• HAEMOGLOBIN.• WBC( total & differential

count.)• ESR.• BLOOD SUGAR.• CHOLESTROL.• URINE EXAMINATION.

SPECIFIC *FOR HYPERTHYROIDISM: == SERUM T3 & T4 LEVEL ==SERUM TSH LEVEL. *FOR OCULAR MUSCLE ENLARGEMENT: ==PLAIN X-RAY CALDWELL

VIEW(PA view) ==ORBITAL ULTRASOUND ==CT SCAN ORBIT ( AXIAL &

CORONAL VIEW) ==MRI

Axial CT scan showing enlarged extra ocular muscles in thyroid eye disease

TREATMENT

GENERAL MANAGMENTCONTROL OF OCULAR DISCOMFORT=Artificial tears=Topical lubricants=SunglassesADVISE THE PATIENT TO=Avoid smoking as it worsens the prognosis=Avoid dust =Elevate head when sleeping to avoid periorbital edema

MEDICAL MANAGMENTCONTROL OF HYPERTHYROIDISM• Iodine and antithyroid drugs• Radioactive iodineORBITAL DECOMPRESSIONSystemic steroids:• Oral prednisolone: 60-80mg/day (dose should be

tappered after reduction in symptoms)• I/V methylprednisolone: 0.5g in 200ml isotonic

saline over 30 min(may be repeated after 48 hrs)

SURGICAL MANAGMENT

Surgical treatment when there is severe sightthreatening condition or for cosmetic purpose.ORBITAL DECOMPRESSION: (for advanced proptosis & optic nerve compression)

STRABISMUS SURGERY: (to minimize diplopia)

LID LENTHENING SURGERY

OTHER MANAGEMENT OPTIONS

RADIOTHERAPY• ORBITAL RADIOTHERAPY

CAN BE USED TO TREAT OPHTHALMOPLEGIA BUT HAS LITTLE EFFECT ON PROPTOSIS.

• THE RADIATION(1500-2000 Cgy fractioned over 10 days) IS USUALLY ADMINISTERED VIA LATERAL FIELDS WITH POSTERIOR ANGULATION

FUTURE OPTIONS• ANTI-TNF α ANTIBODIES(eg infliximab)