in activity.
Fig. 5. Assessment of eyelid swelling. a Moderate active swelling. There is definite subcutaneous fluid (black arrows) or skin thickening (white arrows), but swelling is not tense. This is more than just fat prolapse as the fat pads are not seen distinctly. b Severe active swelling. There is tense subcutaneous fluid (black arrows) or thickened skin (white arrows). Note that in the upper eyelid, moderate swelling is distinguished from severe swelling by asking the patient to look down slightly: the central part of the skin fold remains a fold and is not rounded in moderate swelling (c), whereas it remains rounded in severe swelling (d). In the lower eyelid with moderate swelling, the fluid does not fold the skin (e), whereas it does in severe swelling (f).
Eyelid Erythema
The localized eyelid erythema of active GO can affect either the eyelid close to the margin, where it may be confused with the much more common condition of blepharitis, or more commonly the area known as the preseptal eyelid, where maximal swelling occurs (Fig. 6). Comparison with the rest of the face helps determine what is abnormal for that individual and therefore likely to represent active GO. Note that localized eyelid erythema can occasionally persist for years.
Fig. 6. Assessment of eyelid erythema. a Normal appearance. b Pretarsal erythema (black arrows). c Preseptal erythema (white arrows).
Fig. 7. Assessment of conjunctival redness. a Normal appearance. b Moderate redness, excluding the redness of the caruncle (white arrow) and plica (black arrow). c Severe redness.
Conjunctival Redness
This does not appear to relate to eyelid retraction and ocular exposure, except where there is actual corneal exposure. Inflammation may extend forwards from the insertion of the lateral rectus and can be assessed by comparison with Figure 7.
Chemosis (Conjunctival Oedema)
Lesser degrees of chemosis need to be differentiated from the common condition of conjunctivochalasis (redundant folds of conjunctiva) often apparent in older subjects. This requires a slit lamp, and comparative photographs and method are shown in Figure 8. However, more severe chemosis can be seen without a slit lamp: simply use a finger to push the lateral lower eyelid upwards over the surface of the eyeball and observe if oedematous tissue is displaced.
Inflammation of the Caruncle or Plica
Inflammation of one or both structures is relatively uncommon but easily diagnosed by comparison with Figure 9. Either is used in the clinical activity score (CAS): only recently was their differentiation appreciated.
Fig. 8. Assessment of chemosis. a Normal appearance (conjunctivochalasis). Separation of reflections from conjunctiva and sclera (black arrow) are ≤1/3 total height of palpebral aperture. b Chemosis. The white arrow shows separation of conjunctival and scleral reflections >1/3 total height of palpebral aperture.
Fig. 9. Inflammation of the caruncle and/or plica. Note the difference in colour between the normal caruncle (a) and the inflamed caruncle (b). Exophthalmos causes the caruncle to prolapse forwards but does not denote caruncle inflammation.
How Reproducible Are These Assessments?
The assessment of soft-tissue signs will always be somewhat subjective, and the validity of attempting to measure them has therefore been called into question [34]. Nevertheless, they remain of great importance, both for patients who endure the disfigurement, as well as for clinicians who need to clarify the disease phase. It therefore behoves us to attempt to make their assessment as reproducible as possible. Studies show that reproducibility can be improved by the use of a comparative atlas and careful methodology [35, 36]; indeed, observers reached agreement in 86%, and kappa values for soft-tissue signs were moderate or good for most features. Although far from perfect, photographic comparison remains the most reliable method for assessing soft-tissue signs.
Table 1. The clinical activity score (CAS), amended after Mourits et al. [11]
| Painful, oppressive feeling on or behind the globe Pain on attempted up-, side, or downgaze Redness of the eyelids Redness of the conjunctiva Chemosis Inflammatory eyelid swelling Inflammation of caruncle or plica |
| Increase of 2 mm or more in exophthalmos in the last 1 – 3 months Decrease in eye movements of 8° or more in the last 1 – 3 months Decrease in visual acuity in the last 1 – 3 months |
| For initial CAS, only score the first 7 items; the maximum score is 7. One point is given for each feature, ≥3 out of 7 points indicating disease activity. Patients assessed after follow-up (1 – 3 months) can be scored out of 10 by including the last 3 items. One point is given for each feature, ≥4 out of 10 points indicating disease activity. |
What Value Does the “Clinical Activity Score” Have?
Mourits et al. [11] devised the CAS in 1989. It remains in widespread use, as it is an easy scoring system that allows the majority of patients to be classified as either active or inactive (Table 1). Patients seen for the first time are scored for 7 points, 2 symptoms and 5 soft-tissue signs. Clarifying the presence or absence of both symptoms and signs is best achieved in conjunction with the protocol and notes of the EUGOGO atlas (www.eugogo.eu). On subsequent assessments any significant change in severity is added to the score. Since its inception, it has become apparent that a significant deterioration in any ocular excursion amounts to 8° rather than 5°, and the atlas reflects this (see also the section “How Is Severity Best Classified?” below). The evidence for the value of the
