Patient History
Edema. Graves disease.
Findings
Contrast-enhanced CT of the orbits is strikingly abnormal. There is diffuse bilateral enlargement of multiple extraocular muscles which include the inferior rectus, medial rectus and superior rectus muscles. There is also enlargement of the bilateral rectus, superior oblique and inferior oblique muscles. There is diffuse enhancement of many of the muscles with areas of low attenuation likely representing mucopolysaccharide infiltration. The enlarged extraocular muscles are resulting in substantial proptosis. There is loss of the perineural fat surrounding the optic nerve at the orbital apex suggestive of optic nerve compression. These findings are characteristic for thyroid ophthalmopathy due to Graves disease.
Visualized portion of the brain appears to be within normal limits. Visualized portion of the paranasal sinuses are well developed and well aerated. The lamina papyracea are intact.
Conclusions
1. Diffuse enlargement of all of the extraocular muscles consistent with a thyroid ophthalmopathy due to Graves disease.
2. Loss of perineural fat surrounding the optic nerve at the orbital apex suggestive of optic nerve compression by the diffusely enlarged muscles.
3. Severe proptosis.
