EUGOGO PROTOCOL FOR ASSESSING GRAVES’ ORBITOPATHY (GO)
This protocol has been developed by EUGOGO for the evaluation of patients with Graves’ orbitopathy in the context of multi-centre clinical trials. It assumes some background knowledge and experience of Graves’ orbitopathy on behalf of the clinician using it, who can be either an ophthalmologist or endocrinologist with some training in ophthalmology.
The present document is intended to introduce and describe the method of assessment to observers before entering data on the EUGOGO case record forms (CRF). Clinical assessments consist of symptoms and clinical signs including measurements requiring specialised equipment (exophthalmometer, slit lamp, perimeter).
Several features of Graves’ orbitopathy (such as redness of the lids) are subjective. In order to minimize observer bias, the protocol should be used with a colour atlas showing examples of each feature, including grades of severity. The protocol contains hyperlinks to this atlas and to other detailed descriptions of other GO features, including examination techniques. The atlas should also be used as a rapid reference guide during the course of the examination, whereas the other hyperlinks are only likely to be utilized initially until the examiner has gained experience in using this protocol.
If features or measurements fall between scores, always choose smaller or milder option.
The decision as to whether a patient has “active” GO is based on assessment of symptoms, soft tissue signs and change in severity. This is also summarised by the clinical activity score. However the observer should not score the presence of eyelid swelling, eyelid erythema or conjunctival redness unless they think that these signs represent inflammation due to the active phase of GO. The scoring of these features therefore assumes that the wider picture is taken into account.
RECORDING OF SYMPTOMS
If symptom significantly present score “yes”
If symptom present only occasionally score “no”
If symptom lasts only for seconds score “no”
If prism worn daily to correct diplopia score “yes” for double vision
and for the Gorman score score “constant”
VISUAL ACUITY
Method: Use Snellen chart or equivalent. Any refractive error should be corrected by spectacles, and distance spectacles should be worn. If optimal glasses correction not available, use pinhole.
SCORING Record with decimal notation (e.g. Snellen of 6/9 =0.67etc.)
RAPD (Relative Afferent Pupil Defect)
Method: Patient fixates in distance.
Observer ensures equal stimulation of each macula (same duration, same relationship of light source to visual axis)
Take extra care if strabismus present. Click on RAPD for more details on how to assess.
COLOUR VISION
Method: test each eye separately at comfortable reading distance using red-green pseudo-isochromatic plates.
SCORING
colour blind patient score “not tested”
< 2 errors per > 15 plates score “normal” unless you are
sure this is significant, i.e. other
evidence of optic neuropathy
SOFT TISSUES
Method: Assess lid swelling, erythema and especially conjunctival redness before any other examination that could affect them.
All 7 soft tissue signs and comparative photos are detailed on pages 2-8
Only 1-5 form part of Clinical Acivity Score (CAS).
1. Eyelid / periorbital swelling
Method: Ensure appearance has changed with disease onset.
Compare both upper and lower eyelid with eyelid swelling in the atlas.
If scores for upper and lower eyelids differ then choose mean, but if categories adjacent then choose higher score.
Examples: 1. upper lid severe / lower lid mild - score “moderate”
upper lid nil / lower lid mild - score “mild”
SCORING Only score “mild”, “moderate”, “severe” if due to active GO.
SCORING Only score “yes” if due to active GO.
If redness due to blepharitis score “no”.
3. Conjunctival redness
Method: Assess before using any drops, and compare with conjunctival redness in the atlas. Assess without slit-lamp, sitting approximately 1 meter from patient.
SCORING Only score if due to active GO.
4. Chemosis
Method: use slit-lamp to distinguish chemosis from conjunctivochalasis.
5. Caruncle and Plical inflammation
Method: examine with or without slit-lamp
Compare right and left eyes, and compare with inflammation of the caruncle and plica in the atlas.
Caruncle is normally yellowish pink and lies medial to plica, which is normally pink
SCORING Either caruncle OR plical inflammation score as “yes”.
Proptosis makes the caruncle more prominent, but this
prominence scores “no” (unless caruncle also inflamed).
EYELID POSITIONS
Method: click on eyelid measurements for details of how to reduce artefact errors.
Correct any abnormal head posture.
Ask patient to distance fixate in primary gaze and relax as much as possible
If primary distance fixation impossible without head posture, put * into CRF
If strabismus present then occlude contralateral eye to enable distance
fixation and measurement
SCORING Record to nearest millimetre as + or –(click here for details)
Lagophthalmos
Method: Ask patient to close their eyes as is asleep, and use pen torch to check if eyeball still visible. For further details of this and Bell’s phenomenon click here
PROPTOSIS
Method: use same Hertel instrument and ideally same observer on each occasion.
use same intercanthal distance (ICD) on each occasion.
For details on a method for consistent results click here.
SCORING
Record Hertel value to nearest millimetre
Record intercanthal distance
Record type of Hertel instrument used
MOTILITY
Method: Any spectacle prism should be removed before motility assessment
Compensatory head posture is noted.
To assess manifest strabismus, head posture is corrected and patient is asked to
distance fixate with preferred eye. A cover – uncover test is performed.
Any area of single vision with or without head-posture is noted (without prism). To do
this accurately may require assessing the field of binocular single vision. (ref: Sullivan
et al. Ophthalmology 1992: 99(4); 575-81).
Monocular excursions in horizontal and vertical directions of gaze are recorded. Ideally a perimeter is used to do this (ref: Mourits et al. Ophthalmology 1994: 101(8); 1341-6).
SCORING
a) Record any abnormal head posture.
b) Record whether or not patient is orthoptropic - i.e is there a manifest squint?
If patient is not orthotropic, record any esotropia or hypotropia during distance fixation with their preferred fixing eye.
c) Record whether patient has any area of single vision when they are not wearing a prism.
d) Record the monocular ductions of each eye.
CORNEA
Method: slit-lamp assessment for scoring, but interpret the risk to the cornea
by assessing Bells’ phenomenon, lagophthalmos and whether cornea remains
visible (click here for details of corneal risk assessment).
SCORING:
Use fluorescein to stain any epithelial defect.
Ulcer: the stained area is more than just punctate staining. A localised corneal opacity, stromal infiltrate, abcess or hypopyon may be present but are not essential to the scoring.
Keratopathy (punctate): Only punctate staining is present.
No: there is no staining or the cornea.
Method: Record with applanation tonometry in the primary gaze position
OPTIC NEUROPATHY
Method: Assess optic discs and choroidal folds – ideally via dilated pupils and with slit-lamp for stereo view.
Using information from visual acuity, pupils, colour testing and fundoscopy, together with any other tests for optic neuropathy (e.g. visual fields), the observer makes a judgement on whether DON present.
SCORING OF DISCS:
Normal discs = score as “no GO Δ”
Abnormalities due to non-GO pathology
(e.g. cupping, atrophy or swelling) = score as “no GO Δ”
Optic atrophy likely to be due to GO = score as “atrophic”
Disc swelling likely to be due to GO = score as “swollen”