Stellate ganglion block (SGB) is expected to be effective in treating various diseases including headaches. However, several reports have described the occurrence of headaches after SGB. We experienced a suspected case of a vertebral artery dissecting aneurysm triggered by an SGB.
A 55-year-old woman had been treated with SGB and pharmacotherapy for left mandibular neuropathic pain after tooth extraction. SGB was performed using a paratracheal approach with palpation of the sixth cervical vertebra in a supine and cervical lordosis position. After 35 minutes of SGB, the patient changed from a supine to a sitting position and suddenly complained of severe headache. We suspected an intracranial hemorrhage, but no evidence of hemorrhage was observed using computed tomography imaging. Four days after the onset of the headache, a magnetic resonance angiography suggested a dissecting cerebral aneurysm with a length of 7.7 mm and a width of 5.1 mm in the right vertebral arteries. In cases of dissecting cerebral aneurysm rupture, the majority of cases report rupture within 3 days of the appearance of headache. However, no change in the size of the dissecting cerebral aneurysm or the exacerbation of the headache occurred in the presently reported patient.
Dissecting cerebral aneurysms frequently occur in the vertebral arteries. Reportedly, the internal elastic membrane of vertebral arteries can easily be subjected to a load through slight extensions with daily cervical rotation, potentially resulting in the formation of dissecting cerebral aneurysms. In the presently reported patient, the dissecting cerebral aneurysm might have been caused by the load to the neck because of the cervical lordosis position and the change in position during SGB.
