Ultrasound-guided bilateral greater occipital nerve block on headache seen after endovascular treatment of ruptured or unruptured intracranial aneurysms: A case report.

Headache is a common symptom in subarachnoid hemorrhage (SAH). Often, pain control is difficult and opioid use can have a complicated effect on the patient's state of consciousness. In this study of 2 cases, opioid consumption was reduced while effective pain control of headache occurring after endovascular treatment of an intracranial aneurysm was achieved using an ultrasound-guided, bilateral greater occipital nerve (GON) block. Case 1 was a 59-year-old male patient with a Glasgow Coma Scale (GCS) of 13 who was diagnosed with Fisher scale grade 3 SAH. Coiling and stenting were performed for an anterior communicating artery aneurysm. Cerebrospinal fluid drainage was provided with a lumbar spinal catheter. Case 2 was a 55-yearold male patient with a GCS of 15 who underwent coiling of a fusiform aneurysm in the left basilar artery and stenting of the stenotic region due to a basilar artery aneurysm. After the procedure, the visual analog score (VAS) of the patients was 9 and 7, respectively, and a bilateral GON block was performed with ultrasound guidance. The VAS score of both patients decreased to 3 and did not exceed 3 during follow-up in the intensive care unit, eliminating the need for additional analgesics. A bilateral GON block provided effective analgesia and significantly reduced the need for other pain relief in both cases.