Painless hypoglossal palsy as an isolated symptom of spontaneous carotid dissection.

Spontaneous internal carotid artery dissection (sICAD) occurs annually in 2.5 to 3 per 100,000 presenting with signs of ischemic events in the majority of cases. In contrast, lower cranial nerve palsy due to peripheral nerve affection is seldom the presenting clinical sign. In symptomatic cases (>90%), sICAD is most commonly accompanied by local pain. We report a case of a 49-year old woman with a left sICAD presenting with isolated ipsilateral hypoglossal palsy as the sole clinical sign. Compared to other cases, local pain was absent and other cranial nerves were not affected. Further, sICAD could not be detected in repeated Doppler-/Duplex-sonography, but magnetic resonance imaging and MR-angiography only.