Intractable Hiccups After Coil Embolization of Partially Thrombosed Posterior Inferior Cerebellar Artery Aneurysm

BACKGROUND: Hiccups are defined as sudden-onset involuntary contractions of the diaphragm followed by immediate inspiration and laryngeal closure, and they are considered intractable if prolonged beyond 1 month. A reflux arc involving phrenic, vagal, and central midbrain modulation is likely responsible for hiccups. We herein report a case of intractable hiccups caused by compression of the dorsal aspect of the medulla oblongata after treatment of a partially thrombosed distal posterior inferior cerebellar artery (PICA) aneurysm. CASE DESCRIPTION: A 51-year-old man presented with severe headache and was diagnosed with subarachnoid hemorrhage. Magnetic resonance imaging and cerebral angiography showed a partially thrombosed distal PICA aneurysm associated with a fusiform aneurysm in the ipsilateral vertebral artery. Based on the limited distribution of the clot, we performed endovascular coil occlusion of the aneurysm lumen followed by parent vessel occlusion for the distal PICA aneurysm. After the procedure, the patient presented with hiccups that could not be controlled by any medications. Magnetic resonance imaging showed an area of hyperintensity at the bilateral dorsal part of the medulla adjacent to the embolized aneurysm. The hiccups spontaneously disappeared 1 month after the procedure, and the abnormal signal findings also disappeared within the same period. The hiccups did not recur for 30 months postoperatively. CONCLUSIONS: In this case, the precise location of the culprit lesion causing the patient's hiccups was the dorsal medulla oblongata. Clinicians should be aware of the possibility of structural or functional disorders of the reflux arc in patients with intractable hiccups.