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

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:

The table below presents GO severity criteria.


Lid Aperture Width

Soft Tissue Involvement



Corneal Exposure

Optic Nerve Status

Mild ( ≥ 1 of the following)

 < 2 mm


 < 3 mm

Transient or absent



Moderate to Severe (≥ 1 of the following)

≥ 2 mm

Moderate to Severe

≥ 3 mm

Inconstant or constant



Sight-threatening (1 out of 2 of last categories)

Not contributory

Not contributory

Not contributory

Not contributory



When grading GO activity, add 1 point for each of the following features:

Then, if the patient has been examined within 3 months, add 1 point for each of the following (compared to previous visit):

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 by Christian Nasr MD

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.