INVOLVEMENT OF THE EYEBROW FAT PAD IN GRAVES ORBITOPATHY

Involvement of the eyebrow fat pad in Graves' disease has never been r eported. We noted that Graves' orbitopathy patients had bulkier eyebro ws due to a larger eyebrow fat pad not associated with the preaponeuro tic fat. A cadaver model was used to show that the eyebrow fat could b e identified with magnetic resonance imaging (MRI) scans. Then, a seri es of Graves' orbitopathy patients were sent for orbital MRI scans, an d the eyebrow fat was measured with maximum lengths and widths. The av erages were compared to two groups of patients, one without orbital pa thology, and one with orbital pathology causing proptosis but not due to Graves' disease. Graves' patients with early orbitopathy and incipi ent optic neuropathy or congestive orbits where optic neuropathy had t o be ruled out had statistically significant larger eyebrow fat pads t han either comparison group. This has clinical significance: The eyebr ow fat may need to be debulked during operations such as blepharoplast y. Furthermore, periorbital fat may play a larger role in the disease process than previously thought.