A man in his early 50s with a history of recurrent, poorly differentiated papillary thyroid carcinoma presented with a sudden onset of large-angle esotropia and bilateral abduction deficit (Figure, A), which were found to be due to bilateral cranial nerve VI palsy. Positron emission tomography revealed a fludeoxyglucose F 18–avid, hypermetabolic mass within the clivus, consistent with metastatic spread of thyroid carcinoma with compression of both abducens nerves. Positron emission tomographic imaging of the orbits (Figure, B) showed the lateral recti (black arrowheads) to be hypometabolic relative to the medial recti (white arrowheads), illustrating the functional effect of cranial nerve VI denervation.
Leskov I, Rasool N, Cestari DM. Hypometabolic Lateral Recti Due to Bilateral Cranial Nerve VI Palsy. JAMA Ophthalmol. 2015;133(9):e151490. doi:10.1001/jamaophthalmol.2015.1490