Endocrine Ophthalmopathy (MRI/CT)	(2)

Idiopathic inflammation or ‘inflammatory pseudotumour’ is another frequent cause of exophthalmos which often causes ocular muscle enlargement. Involvement is usually unilateral and tends to involve the muscles' tendinous insertion into the globe or may even present as an orbital mass. Other causes for exophthalmos are usually unilateral and include benign and malignant tumours (See Neurofibroma (MRI)), vascular malformations, carotid-cavernous fistula, or cavernous sinus thrombosis.

Fig. 24.23a Endocrine ophthalmopathy. Coronal Tl-weighted MR image showing extraocular muscle enlargement of the superior rectus, lateral rectus and inferior rectus of the right orbit. Enlargement of the medial rectus in the left orbit is also present.