DX: Posterior Staphyloma (presumptive) versus Euthyroid Graves Disease

Ok. The first approach in this case was to rule out Graves disease which can cause proptosis due to enlargement of orbital muscles, especially medial rectus muscle which in this case is normal. Also, features of Graves disease include retrobulbar increased fat deposition but with a patient euthyroid (normal thyroid hormones) are less common. But, there is an autoimmune condition when there is symmetrical or asymmetrical orbital proptosis, and with normal thyroid hormones which is a form of Graves Diesease called Euthyroid. Prevalence of this condition ranges between 1.6 and 8.6% (Br J Ophthalmol. 2009;93(8):1052).

Imaging findings in our patient revealed increased antero-posterior lenght in both orbital globes, mostly in the right one that has proptosis. Also, in association, progressive thining of sclero-uveal posterior coating. The thining is more diffuse rather than focal.

Here are the relevant images:

With these findings and normal thyroid levels one has to consider Posterior Staphyloma as the main differential. It is associated with severe miopia, past history of infections and mostly glaucoma. In our patient, miopia was present. Patient was referred to ophtalmoscopic examination.


Here are some useful links:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1311542/

http://radiopaedia.org/articles/staphyloma

http://www.medscape.com/viewarticle/715285


Thanks to Dr. Morales for your comment. All comments are welcome.