Isolated ocular motor nerve palsy in dural carotid-cavernous sinus fistula

The incidence of dural carotid-cavernous sinus fistula (DCCF) presenting as isolated ocular motor nerve palsies without congestive ocular features is unknown. We reviewed the DCCF patients in our hospital during the last 10 years to elucidate the clinical and neuroradiological features of DCCF with isolated ocular motor nerve palsy. Eleven amongst the 33 DCCF patients presented isolated ocular motor nerve palsy. All the 11 patients underwent brain CT/CT angiography (CTA) and/or MRI/MR angiography (MRA), before the digital subtraction angiography (DSA). The compromised nerves were the oculomotor nerve in eight (72.7%), abducens nerve in two (18.2%) and trochlear nerve in one (9.1%). Brain CT and/or CTA were conducted in four patients but all unremarkable. MRI and/or MRA were performed in nine patients and six of them showed compatible findings of DCCF. The diagnoses of DCCFs were confirmed by DSA and all were posterior-draining type. The outcome was good, with a total recovery rate of 54.5% within 12 months. Thirty-three percent (11 of 33) of our DCCF patients presented with isolated ocular motor nerve palsy, which is not uncommon. MRI and MRA are of value in the initial evaluation, but DSA is necessary for the accurate diagnosis and treatment planning.