The Evaluation and Treatment of Graves’ Opthalmopathy
The full article provides a useful overview of the pathophysiology, epidemiology, diagnosis, evaluation, and treatment of Graves’ ophthalmopathy (GO).
This summary of the article will focus on the classification of GO.
Basic Graves’ Ophthalmopathy Information
- Most patients with GO have a history of Graves’ disease with hyperthyroidism; about 25% to 50% of Graves’ hyperthyroidism patients have clinical eye involvement.
- Some GO patients, however, are euthyroid or hypothyroid (caused by Hashimoto’s thyroiditis).
- In 80% of patients, regardless of whether GO or Graves’ hyperthyroidism develops first, the other condition develops within 18 months.
Severity of the Disease
In order to effectively manage GO, an accurate assessment of the severity of the disease must be made. The degree of active inflammation present must also be taken into account.
GO can be mild, moderate to severe, or sight-threatening. In order to reach that assessment, the following must be evaluated:
- Lid aperture width
- Proptosis measurement (variation compared with each race’s norm—or if available, to the patient’s baseline)
- Diplopia score
- 1 = intermittent (upon awakening or when tired)
- 2 = inconstant (only at gaze extremes)
- 3 = constant
- Degrees of eye muscle abduction
- Corneal examination (looking for exposure keratitis or ulceration)
- Option nerve function
The table below presents GO severity criteria.
Severity |
Lid Aperture Width |
Soft Tissue Involvement |
Proptosis |
Diplopia |
Corneal Exposure |
Optic Nerve Status |
|
Mild ( ≥ 1 of the following) |
< 2 mm |
Mild |
< 3 mm |
Transient or absent |
Absent |
Normal |
|
Moderate to Severe (≥ 1 of the following) |
≥ 2 mm |
Moderate to Severe |
≥ 3 mm |
Inconstant or constant |
Mild |
Normal |
|
Sight-threatening (1 out of 2 of last categories) |
Not contributory |
Not contributory |
Not contributory |
Not contributory |
Ulceration |
Compromised |
When grading GO activity, add 1 point for each of the following features:
- Chemosis
- Eyelid swelling
- Eyelid erythema
- Conjunctival erythema
- Caruncular swelling
- Pain in primary gaze
- Pain with ocular movement
Then, if the patient has been examined within 3 months, add 1 point for each of the following (compared to previous visit):
- Decreased visual acuity
- Worsened diplopia
- Increased proptosis
This assigns a Clinical Activity Score (CAS) with a range of 0 to 10. A score of 10 is possible only if a patient has a previous assessment.
In patients with no previous assessment, GO is considered active with a CAS of 3 out of 7.
In patients with a previous assessment, it is active with a CAS of 4 out of 10.
Commentary
Graves’ ophthalmopathy (GO) is an eye disorder encountered exclusively in autoimmune thyroid diseases, most commonly Graves’ disease. Patients are not always hyperthyroid at presentation, and they may even be hypothyroid. GO may precede the onset of the thyroid dysfunction at times.
Graves’ ophthalmopathy (GO) is fortunately mild in most patients. In some cases it can be disabling and occasionally sight-threatening. It is crucial that the clinician obtain a baseline ophthalmic evaluation that includes visual fields and exophthalmometry on every patient with Graves’ disease and make the eyes an essential component of the systems review at every visit to be able to detect significant symptoms. Periodic exophthalmometry is recommended afterwards.
The Clinical Activity Score is a practical tool that helps the clinician assign an index of disease activity to GO, determine whether the eye disease is progressing, accurately communicate with the ophthalmologist, and make a decision on the timing of any needed intervention.
