Graves opthamology Flashcards
where is the thyroid gland located
highly vascular endocrine gland
lower neck anterior to trachea between the sternocleidomastoid muscles
consists of densely packed follicles
what is the function of the thyroid gland
concentrates iodide to form thyroid hormones
thyroid hormones synthesised and stored in the follicles
what are hormones does the thyroid secreate
trh stimulates the release of tsh
tsh is secreted by the anterior pituitary and stimulates the secretion of t3 - try-idothyroine
tetra idothyroonine t4 (thyroxine)
t3 and t4 recreated into bloodstream
bound to plasma proteins
free from intracellular
what are the roles of thyroid hormones
growth and development
rate of growth and many tissues
maturation of cns and bones
regulation of synthesis and some respiratory enzymes
metabolic effects
regulation of basal metabolic rate
regulation of water and ion transport
regulation of calcium and phsophorus metabolism
regulation of nitrogen metabolism
what is hyperthyroidism
enlarged thyroid gland - goitre
abnormal heart rhythms- tachycardia
increased appetite but may have weight loss
hand tremors
fine brittle hair
hyperactivity
heat intolerance and increased perspiration - warm , moist skin
lighter or less frequent periods
irratability
anxiety
muscle weakness - upper arms and thighs
what are symptoms of hypothyroidism ( underachieve)
fatigue , exhaustion
feeling run down and sluggish
unexplained / excessive weight gain
dry coarse , itchy skin and hair
slow heart rate
feeling cold , especially in extremities
goitre
more frequent periods
difficulty concentrating - brain fog
hoarse voice
muscle cramps
how are thyroid abnormalities diagnosed
tsh (considered outside normal if lower than 0.3 or higher than 3.0
calculate free t4 index (10-20)
thyroid stimulating immonoglobin (tsi)
anti thyroid antibodies
serum t3 - 2.5- 5.3 pmd
hyperthyroidism management
drug therapy
radioactive iodine treatment
thyroidectomy
hyperthyroidism treatment
thinomines - interfere with thyroid hormone synthesis by blocking the build of iodine
most effective if the onset of disease within 1 year
steroids- oral prednisone - decreases secretion of thyroid hormones and peripheral conversion of t4 and t3 - used in severe cases
immunosuppresants ( azathioprine or rituximab)
how is radioactive iodine used in the treatment of ted
radioactive iodine - taken up by thyroid gland - normal cell division = disturbed
used in patients over 45 yrs of age or in Younger patients if other treatments are contraindicated
ocular symptoms have been found to worsen following this treatement
20% of patients become hypothyroid within 1 year of the treatment
what effect does radioactive iodine and prohlaytic corticosteroids have on GO wheen treating hyperthyroidism
prevents progression of go in patients with pre- existing eye disease
eye signs worsened 6 months in
15% after ri
2.7% after antithyroid drugs
none who had ri and prednisone
how is a thyroidectomy used to treat hyperthyroidism
removal of the thyroid gland
reduces hormone production
post op recurrence in 10-15% patients
post op hypothyroidism in 40% of patients
usually performed in younger patients
what is used in patients with hypothyroidism
oral thyroxine
what is graves disease
autoimmune disorder that causes hyperthyroidism - the immune system attacks the thyroid and causes it to make more thyroid hormone the body needs
3 patients
all with enlargement of the thyroid gland
all with palpations
1 with protusion of the eyes
what is graves orbitoptahy
auto immune disease
disease of the orbit affecting the orbital soft tissues
closely correlated to auto immune systemic thyroid disease
presence of circulating antibodies that bind and stimulate the thyroid hormone receptor (tsh) leading to hyperthyroidism and goitre
what are risk factors of graves orbitopathy
genetic
environmental- smoking , stress
immune factors
what are risk factors of graves orbitopathy
female - 86%
16/10 000 women
3/ 10 000 men
Age- women - 40- 50 years
men 50- 55 years
greater severity with age
smoking- may known risk factor
severity of eye signs and symptoms with increased tobacco consumption
what thyroid abnormalities are associated with graves orbitopathy
hyperthyroidism - 90%
hypothyroid - 3-5%
euthyroid- 5% - sensitivity of detection]
patients hyperthyroid without eye signs - 50- 60 % - 80- 90% have eom changes on ct imaging
what are symptoms of thyroid eye disease
most common is change in appearance and/or ocular irritation
dry eyes
epiphora
grittiness
diplopia
photophobia/ flashing lights
reduced vision/ colour vision
pain/ ache on extreme gaze
distress at changing apperance
what lid abnormalities are seen in thyroid eye disease
upper or lower lid retraction
palpebral appeture - measurement can be taken
how to measure lid retraction
position patients head
ask patient to fixate on target positioned at their eye level and in the distance
ask patient to relax as much as possible to record the minimum amount of retraction for that patient (I.e Mullers muscle as relaxed as possible)
observer holds vertical clear plastic ruler near to visual axis without touching patients eyelashes
observer should consistently use only one of their eyes near to visual axis without touching eyelashes
observer should consistently use only one of their eyes and on the same horizontal level as the patients eye
for patients with manifest strabismus the contralateral visual axis is occluded prior to measurement
what instrument is used to measure exophthalmos/ proptosis
hertel mirror exopthalmometer
what should be noted about exopthalmos
if its bilateral
asymmetric
unilateral
normal
amount depends on severity of disease and inflammation and the structure of anterior orbital septum
axial/ non axial
what relating to oedema is caused by ted
lid oedema / periorbital odema
what relating to the conjuctiva can be caused by ted
inflamamation of caruncle
chemises, conjuctiva redness and swelling
what is affected in the eyes by graves orbitopathy
extra ocular muscles
orbit
lids
sight
what happens during the wet phase (active phase) to extraocular muscles
wet phase- active phase
cellular infiltration with gags (glycosminoaglycans( and osmotic inhibition of water
this leads to eom becoming up to 8- 10x enlarged
may compress optic nerve leading to visual loss
subsequent degeneration of muscle fibres leads to fibrosis resulting in restricted motility and diplopia
this phase tends to settle within 3 years
what is the fibrotic phase
muscle fibres become distorted , contracted and damaged due to fibrosis
eyes are white and quiet
painless restrictive myopathy may be present
what details need to be noted/ assessed regarding eom
limitation
reversal
saccades
cog wheel pursuit
fatigue
pain
retraction
bilateral involvment
what is the order of eoms involved in ted
inferior rectus
medial rectus
superior rectus, lateral rectus
superior oblique and inferior oblique
vertical , horizontal and torsional diplopia
swelling of eom results in restriction : if ir affected then patient unable to elevate as eye becomes tethered down
what is graves orbitpoathy and how is diagnosed
go is an autoimmune condition diagnosed by blood tests along with clinical history and assesment
MRI scans can aid diagnosis
patients are usually hyperthyroid but can be hypothyroid or euthyroid
management of thyroid levels is an important first step in treatmenr 3 phases
multiple distinctive eye signs
can result in painful eye movements diplopia or visual loss
upgaze typically affected first
what signs need to be present for a patient to be diagnosed with ted
clinical orbital signs `(lid retraction/ proptosis/ optic neuropathy)
laboratory tests (positive bloods for autoantibodies)
typical orbital imaging finding = swollen eoms
what are the signs and symptoms seen in the mild and early stages of ted
symptoms include—–
foreign body sensation
dry ete - excessive tearing , conjunctival or eyelid redness and swelling
blurred vision
retro - orbital pain
clinical signs include ——-
mild soft tissue inflammation
dilated conjunctival vasculature
keratoconjuctivitis
corneal staining
what signs and symptoms seen in the moderate stage
pulling sensation around the eye
eyelid redness and swelling
what signs and symptoms seen in the moderate stage
pulling sensation around the eye
eyelid redness and swelling
eyelid retraction and bulging eyes
swelling of eom s
cheomosis
eyelid oedema
proptosis
what symptoms would you see in advanced ted
horizontal, vertical and torsional strabismus with double vision
deteriorating blurred vision
fading colour vision in one or both eyes
decrease in va , visual field and colour vision
signs of optic neuropathy
progressive proptosis with eyelid retraction
corneal ulceration
inflammation og eom and scarring leading to strabismus and opthalmolplegia
increased top
describe the summary of the orthoptic role
diagnosis
assessment of visual function
document effects of ocular muscles
record disease progress
establish when ocular signs stabilise
explaining and information signposting
eliminate symptoms / diplopia
plan long term management
outline the orthoptic investigation
ct , visual function , note any app - most common , head elevation
om and measure pa
bsv tests (inc vpfr)
pct + torsion
(synoptophore or torsionometer)
funicular field of fixation
field of bsv
lees screen / hess (not useful in bilateral cases)
measure 9 position of gaze due to them having an incomitiant deviation
what parts of visual function would be assessed
visual acuity
colour vision - 100 hue , d15
Ishihara is used for congenital conditions
visual fields
contrast sensitivity
pupils - checks for optic nerve , damage which may occur if on compression
what are the clinical; signs of optic nerve compression
on compression = a ocular emergency
reduced va
reduced contrast sensitivity
reduced colour viision
visual field defect
rapd- relative afferent pupillary defect
optic disc exam - normal/ swelling/ pallor
optic neuropathy - approx - 5 %
with an acute presentation of ted what could you differentially diagnose it with
carotid - cavernous fistula
mystic pseduotumour
ocular myosotis
leukemia
orbital myositis
chronic progressive external opthalmalplegia
idiopathic orbital inflmmatory disease
lymphoprolferative disorders
carticocavernous fistula
myasthenia gravis (in elderly males with inactive disease)
what classifications are seen for the diagnosis
Werners classification
mouritis cas
eugogo
what is Werners classification of ted
stage 1 - no ocular signs - stage 7 - sight loss
how does the European group on graves orbitpopathy
combines clinical activity score with measures of severity
1- spontaneous retrobulbar pain
7- conjunctival odema
what are the surgical mangement options
surgical - sight saving , strabismus, lid
what are the aims of orthoptic management
perserve visual function
keep patient comfortable and symptom free
allow comfortable bsv in primary position and reading poistion where possible
what are the management options for ted
encourage use of ahp
what are the management options for orthoptic management
encourage use of ahp
prisms - tempoary / incorporated
occlusion - blendaderm / patch / frosted lens
surgery
BT
What needs input from a opthamologist- non urgent
non urgently - gritty sensation/ and or eyes sensitive to light progressive change in eye appearance
pain in or behind the eyes
diplopia
eyelid retraction
swelling / redness of eyelids or conductive
restriction of eye movement
tilting of head to avoid double vision
what urgently needs input from the opthamologist
sudden deterioration in vision
problems with colour vision
sudden onset proptosis
failure of full eye closure
corneal opacity
abnormal disc possible described referral to eye/ casualty or optmetrist
what surgical interventions can be suggested
on compression - orbital surgery
strabismuss / ocular realignment surgery
lid surgery
multidiscpilanory approach - may involve maxillary facial surgeons , strabismologist and orbital surgeons
what orbital changes are seen in ted
retrobulbar adipose tissue is increased in volume and may have lymphocytic infiltrate
increased volume of orbital contents typically leads to exophthalmos
what orbital changes are seen in ted
retrobulbar adipose tissue is increased in volume and may have lymphocytic infiltrate
increased volume of orbital contents typically leads to exophthalmos
may lead to on compression / neuropathy
what are the treatment options for optic neuropathy
steroids
radiation
orbital decompression
what type of steroids are given for optic neuropathy
mechanisms - anti-inflammatory
immune response - immunosuppressive
decrease mucopolysaccharide production by orbital fibroblasts
indications -
acute inflammatory disease
optic neuropathy - mid va loss
recent onset
following other treatments - pre/post decompression
what are the effects of steroids + azthioprine
another immunosuppressants
allowing reduction of steroid if prolonged large doses - reduces side effects of steroids
effects modest
what are the effects of radiation therapy
well tolerated
no short term side affects
reduces symptoms but not the course of disease
referral to oncologist
face mask to immobilise patient and allow accurate delivery of radiation
planning with ct
2 weeks of treatment delivered daily
how does radiotherapy work
reduce the cells which cause inflammation so reduce swelling behind the eye
it may take up to year to notice the full effect
10 radiotherapy treatments given over two weeks
face mask to immbolise patient and allow accurate delivery of radiation
risk of cataract
risk of dry eyes
how is radiation therapy utilised in the treatment of ted
daily doses od radiation beams directed at the orbital area
low dose of 26y x ten days
destroys lymphocytes and fribroblasts reducing auto immune response
first weeks often in conjunction with steroids
increased chemises in the first week of treatment
improvement after 2 weeks of treatment
if no improvement in 1 month treatment unlikely to improve
in what type of patients is radiation therapy indicated
indicated in patients with
severe acute soft tissue signs ( steroids initially as radiotherapy not intermediate)
recent onset progressive proptosis
acute opthalmoplegia
acute vision loss
where steroid treatment has failed
in what type of patients is radiation therapy contraindicated
contraindicated/ not effective in patients with
chronic ted
minimal or no inflammation
proptosis without inflammatory changes
longstanding restrictive myopathy or rapid progression of disease
male patients / smokers
age under 50 years
how does radiotherapy treatment effect the clinical activity score
patients with a score lower than a 4 see a 80% chance of improvement
patients with a score higher than a 4 see a 36% chance of improvement
4= swelling of lid (erythema)
what is orbital decompression
an operation to remove bone from the walls of the orbit- the eye socket- in order to reduce the amount of protusion in the eye
this can be done laterally
transantral
transfrontal
ethmoidal
maxillary
what are indications for orbital decompression
- sight threatening situations improve cosmesis (40%, Lyons and footman)
what type of orbital compressions willl be perfumed
lateral orbital wall (single) - moderate proptosis
medial wall and medial half of the floor and lateral wall are removed (severe proptosis)
patients with sight threatening orbitopathy
orbital fat decompression alone - mild proptosis
what are some of the complications regrading orbital decompression
complications include - temporary lib numbness
sinusitis
orbital cellulitis
meningitis
lower lid entropic
blindness 1/10000
asymmetric correction of proptosis
apparent upper lid retraction
epiphora
diplopia
how is strabismus associated with ted
occurs in 15-51% with ted
diplopia which impacts on work/ driving ability to function independlty
vertical
what are indications for strabismus surgery
medical condition stable
eye condition stable
problematic diplopia
uncomfortable head posture
centralise/ and or enlarge field of bsv
what type of eom surgery can be performed
forced auction testing - pre, intra and post up
recession of muscles , avoid resections
free adhesions
undercorrection
adjustable sutures - allow fine tuning and adjustment of app
inferior rectus dissected from attachments to lower lid
inferior rectus recession
medial rectus recession -
preferably wait for 6 months of stability
how are the lids affected in ted
lids retraction
(upper and lower lid)
levator palpeerde superioris muscle fibre enlargement oedema - rarely affects function
overaction of mullers muscle (sympathetic overaction)
innervation to superior rectus and levator palpable superioris
what drugs can be given for lid retraction
guanethidine
topical drops -alpha adrenergic blocking agent
triamcinolone - oral
anti- inflammatory - anti fibrotic effect
what procedures can be done for lid retraction
levator muscles procedures
mullers muscles procedures
combination of above
aim to leave ptotic - gradually elevates
lateral tatsoophary- not effective - not used - may prevent exopthalmos
what levator muscle procedures can be done
recession
tetnotomy
what is Hendersons operation
lid retraction - weakening of mullers muscles
what can be done to help peri- orbital oedema
blepharoplasty- surgical correction of lid deformity
mark out excessive skin
excuse skin and obicularis
remove fat
what are the complications of a belphorplasty
infection
bleeding
dry / irrated eyes
difficulty closing eyelids
what can be done to protect the cornea
tape lids
glasses with Side protection
hypromellose
steroids
orbital decompression
tarsorraphy
what is rituiximab used for
ritxumab is a drug which depletes B cells promoting antibody dependent cellular toxicity
sustained resolution of optic neuropathy and inflammation was found - no improvement of proptosis and strabismus
what is tepezza used for
new medicine to treat go
human monoclonal antibody
approved for use in use in jan 2020
expensive -
what does tepezza do
reverses proptosis by reducing inflammation and preventing tissue expansion - reduces diplopia and strabismus and orbital soft tissue volume in patients chronic ted
imaging studies show reduction in eom size
possibly Better strabismus outcomes
what are the side effects of tepezza
only medication that reduces fat and muscle expansion within the orbit
only medicine to possibly reduce on compression
some patients remain non responders to treatment
possible side effects - hearing los , hypergluceima and muscle spasm
