Dissection of a Limb of a Vertebral Artery Fenestration: Case Report

Abstract

Can J Neurol Sci. 2016; 43: 329-331 Fenestrations of vertebral and basilar arteries are considered to be rare, congenital malformations observed in angiographic and autopsy studies. They are vascular abnormalities having two different lumens and endothelium layers, sharing either the same or separate adventitia layers. Basilar artery fenestration is an uncommon developmental anomaly occurring in 1% to 5% of autopsy specimens, 1 Vertebrobasilar junction fenestration is considered to be a subtype of fenestration of the proximal basilar artery. Association of a saccular cerebral aneurysm at the fenestration has been well documented. However, dissection of a limb of the vertebral artery fenestration is extremely rare. We describe a case of dissection of the left limb of a left vertebral artery fenestration that initially presented itself as a suspected vertebrobasilar aneurysm. CASE REPORTA 55-year-old man awoke suddenly from sleep with a sudden onset, severe headache behind the left eye lasting approximately ten minutes. The headache was associated with ataxia, diaphoresis, and vomiting. He also recalls an unusual symptom of dysphagia, which lasted approximately ten minutes. All symptoms resolved spontaneously within 15 minutes. He recalls having a similar headache one year ago, which resolved spontaneously. The patient is a single, marine engineer, with a history of hypertension that was managed with olmesartan at the time. He does not drink or smoke and has no significant personal or family history of cardiac or cerebrovascular disease.By the time the patient arrived at the local emergency room, he was asymptomatic. He was evaluated for a possible cardiac cause and was discharged that evening without further investigations secondary to unremarkable findings. After investigating his symptoms on the Internet and becoming concerned he had a cerebral aneurysm, the patient presented to the emergency department at our institution three days later. A lumbar puncture (LP) showed acellular cerebrospinal fluid (CSF) without xanthochromia and a computed tomography (CT) scan of the head without contrast was normal.At this stage, it was appropriate to identify the cause for the patient's dysphagia, which was presumably due to transient ischemia to the lateral medulla (nuclei of cranial nerves IX and X). Thus, the differential diagnosis of a thunderclap headache with associated ataxia, vomiting and dysphagia would include the following:• aneurysm-related subarachnoid hemorrhage (SAH), with vasospasm resulting in focal cerebral ischemia;• reversible cerebral vasoconstriction syndrome (RCVS), with or without associated SAH and focal cerebral ischemia;• artery dissection with focal cerebral ischemia;• occlusive atherosclerotic thromboembolism with focal cerebral ischemia and;• migraine with brainstem aura.Although migraine with brainstem aura can present suddenly and be associated with focal neurological signs and symptoms, dysphagia would be an unusual symptom in relative isolation. Given a negative LP and a CT scan that was...

Dissection of both limbs of a fenestrated vertebral artery: Case report and review of literatures

“…To our knowledge, only six cases have been reported (Table 1). 4,6‐10 Furthermore, in our case, both limbs were affected. This is the first case showing dissection in both limbs of fenestration.…”

“…Fenestration of VA is an anomaly due to the existence of embryonic vascular networks persisting after birth 1,3 . It is a rare anomaly, with a reported incidence of 0.23%‐1.95% 4 . Commonly, it has no pathological significance.…”

“…Nicola et al 4 reported a case with a thrombus in the dissected cavity of a fenestrated VA, although the arterial cavity of the dissected VA was not opacified due to occlusion on MRA, CTA, or angiography. Also, it was not recanalized for 6 months from the onset 4 . From radiological findings, the authors speculated the diagnosis of dissection of a fenestrated VA limb.…”

“…1,3 It is a rare anomaly, with a reported incidence of 0.23%-1.95%. 4 Commonly, it has no pathological significance.…”

“…Also, it was not recanalized for 6 months from the onset. 4 From radiological findings, the authors speculated the diagnosis of dissection of a fenestrated VA limb. In our case, an intramural thrombus was detected on 3D-T1 fat suppression WI of MRI in both limbs of fenestration.…”