A 67-year-old female with a medical history of hypertension and active smoking presented to the emergency department after experiencing a severe headache of sudden onset in the right side of her head. The patient had undergone elective screening colonoscopy the day prior. The morning following the colonoscopy procedure she woke up experiencing a right-sided headache associated with nausea, right-arm pain, right eye blurry vision, and slight fingertip numbness on her right side after which she decided to come to the hospital. She denied any recent trauma, fever, chills, or neck stiffness. On physical examination, she was neurologically intact.\nNoncontrast head CT demonstrated no acute intracranial pathology, specifically no evidence of subarachnoid hemorrhage. CT angiogram (CTA) demonstrated a 4.2 × 4.2 × 4.2 mm fusiform aneurysm arising off the superior cerebellar artery, approximately 1.5 cm distal to its origin off the basilar artery. The headache subsided the following day. Diagnostic cerebral angiogram was performed and redemonstrated the fusiform aneurysm, essentially unchanged in appearance when compared to the CTA []. The patient was started on dual antiplatelet agents consisting of clopidogrel 75 mg daily and aspirin 325 mg daily. One week later, the patient underwent successful Pipeline embolization of the aneurysm []. Briefly, a 6-Fr sheath was inserted into the right common femoral artery and a 6-Fr Benchmark guide catheter (penumbra) advanced over a diagnostic catheter and glide wire into the right vertebral artery. Through the guide catheter, a Phenom Plus distal access catheter was advanced over a Phenom microcatheter and Synchro-2 microwire into the proximal basilar artery. The microcatheter was then advanced over the microwire into the right superior cerebellar artery distal to the aneurysm. A 2.5 mm wide and 10 mm length Pipeline embolization device was then deployed along the fusiform aneurysm. Postdeployment angiogram demonstrated excellent apposition of the device to the parent vessel and evidence of some contrast stagnation within the aneurysm.\nThe patient was neurologically intact postoperatively and was discharged home on postoperative day 2. A cerebral angiogram performed 6 months later demonstrated resolution of the aneurysm with patency of the superior cerebellar artery []. The patient had no complaints and was neurologically intact.
A 52-year-old woman suddenly experienced vertigo and vomited while cleaning her bathtub at home and was subsequently transferred to our hospital by an ambulance. Head CT showed no abnormal findings, thus she was admitted under the suspicion of acute drug poisoning by a detergent. Although no abnormalities on a physical examination or in laboratory data were observed, her nausea and dizziness persisted. Neurologically, she presented only mild dizziness. MRI was then performed at 4 days after the onset, which showed an acute infarction in the left cerebellar hemisphere (Fig. ). The left VA was poorly visualized on MRA as compared to the right VA (Fig. ). In addition, the external diameter of the left VA on basiparallel anatomic scanning (BPAS) was narrowed, suggesting hypoplasia. The proximal portion of the left PICA was not visualized, and the adjacent distal portion appeared to be dilated on MRA (Fig. ). T1-VISTA showed a high-intensity signal area at the dilated portion (Fig. ). Conventional T1 image was obtained on admission and at 24 days after admission, but no high-intensity area was observed at both time points. Cardioembolic causes were excluded by echocardiography and 24-hour electrocardiography. According to these findings, Ischemic stroke of the cerebellum caused by dissection of the left PICA was diagnosed, and the administration of unfractionated heparin was started. Three days later, the dilated portion was enlarged on MRA, therefore, we discontinued unfractionated heparin administration. Since her blood pressure was not high, we even didn’t use antihypertensive treatment. At 8 days after the onset, cerebral angiography demonstrated the “pearl and string sign” at the proximal portion of the left PICA (Fig. ). Dilatation gradually normalized on MRA and the high-intensity signal area on T1-VISTA gradually reduced and disappeared at 4 months after the onset (Fig. ).