A 56-year-old woman began to suffer from an occipital headache for 7 days before admission to our hospital, and dizziness appeared 5 days later. On admission, she complained of dizziness and a mild occipital headache. She showed nystagmus and the right nose-finger-nose test was positive. In peripheral blood cell counts and biochemical studies, elevations in white blood cells (9,200/μl) and low-density lipoprotein cholesterol (215 mg/dl) were observed. Coagulation studies and immunological studies were normal. Head computed tomography (CT) showed low-density areas in the right cerebellar hemisphere, diffusion weighted imaging (DWI) of magnetic resonance imaging (MRI) displayed high-intensity signal areas in the cerebellar vermis and the right cerebellar hemisphere (Fig. ). In addition, a high-intensity signal area was observed just adjacent to the right VA on T1-VISTA (Fig. ), whereas no such high intensity was detected on conventional T1 image. Conventional MRA did not depict the right PICA or any abnormal findings of the right VA (Fig. ). Echocardiography and 24-hour electrocardiography showed no findings suggestive of cardioembolic causes. According to these findings, ischemic stroke of the cerebellum induced by the right PICA-D was diagnosed, and after confirming that she had neither hypertension nor aneurysmal formation, combined therapy with clopidogrel and unfractionated heparin administration was started. T1-VISTA showed a slight expansion of the high-intensity area at 3 days after admission, but still no lesions on T1 images. At 9 days after admission, cerebral angiography revealed the “pearl and string sign” at the proximal portion of the right PICA (Fig. ). At 12 days after admission, the patient was discharged with single antiplatelet therapy (clopidogrel). On T1 images, a pale high-intensity area was documented at the dissected lesion at 19 days after admission. Thereafter, the right PICA was gradually depicted on MRA and completely visualized at 5 months after the onset. In parallel with that, the high-intensity signal area on T1-VISTA gradually decreased in size and disappeared by 5 months after the onset (Fig. ). Clopidogrel administration was then stopped.
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.