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CASE REPORT
Year : 2020  |  Volume : 68  |  Issue : 1  |  Page : 176--178

Cryptogenic Stroke Secondary to Rare Carotid Web?

Hongwei Liu1, Wenxia Wang2, Xiaolian Xing2, Jing Shi2, Xiaolong Wang2, Weirong Li2,  
1 Department of Neurology, TaiYuan Central Hospital, Shan Xi Medical University, Taiyuan, China
2 Department of Neurology, TaiYuan Central Hospital, Shan Xi Medical University, ShanXi Province, China

Correspondence Address:
Dr. Weirong Li
Department of Neurology, TaiYuan Central Hospital, Shan Xi Medical University, ShanXi Province
China

Abstract

Understanding the pathogenesis and the typical imaging features of carotid artery web, and accurately diagnosing the carotid artery web will help to implement targeted intervention for cryptogenic stroke and reduce the recurrence of stroke events. Carotid web (CW) can be defined as an endoluminal shelf-like projection often noted at the origin of the internal carotid artery just beyond the bifurcation. It is recognized as a possible cause of ischemic stroke in young adults. We describe here a case of ischemic stroke caused by a CW in a healthy man. Detection of this vascular abnormality required the use of computed tomography angiography. CW is a specific anatomical structure. Its imaging and clinical manifestations are different from atherosclerosis. It's also is a latent etiology to cryptogenic stroke. CW should be considered in patients with otherwise cryptogenic stroke, otherwise healthy patients presenting with stroke and without the typical risk factors for atherosclerotic carotid disease and stroke.



How to cite this article:
Liu H, Wang W, Xing X, Shi J, Wang X, Li W. Cryptogenic Stroke Secondary to Rare Carotid Web?.Neurol India 2020;68:176-178


How to cite this URL:
Liu H, Wang W, Xing X, Shi J, Wang X, Li W. Cryptogenic Stroke Secondary to Rare Carotid Web?. Neurol India [serial online] 2020 [cited 2020 May 27 ];68:176-178
Available from: http://www.neurologyindia.com/text.asp?2020/68/1/176/279656


Full Text



Carotid webs (CW) are rare and easily misdiagnosed, especially when a patient has a special condition. Here we report a CW case and summarize the morbidity and imaging characteristics of CW.

Cryptogenic strokes (CSs) are symptomatic cerebral infarcts for which no probable cause can be identified after either standard assessments or standard plus advanced assessments. Cryptogenic strokes account for 10% to 40% of all ischemic strokes.[1],[2],[3]

As research into stroke etiology and pathogenesis has advanced, and both classification and diagnostic techniques have improved, the medical understanding of CS has gradually changed. An increasing number of probable causes for uncertain strokes have been identified. In clinical practice, it is possible to design secondary prevention strategies when the cause of the stroke is known.

 Case Report



A 52-year-old man without cerebrovascular risk factors presented with an acute middle cerebral artery stroke. He reported never smoking or drinking and had no medical history of recent surgery or trauma. There was no family history of either genetic cerebral and myocardial infarction. Diffusion-weighted imaging (DWI) [Figure 1]a performed four days after symptom onset showed increased signal intensity with low apparent diffusion coefficient (ADC) [Figure 1]b. A craniocervical computed tomography angiogram showed bilateral narrow, hibateral, smooth, intraluminal filling defects along the posterior wall of the internal carotid bulb that was compatible with CWs. The defect was more prominent on the right side. No other abnormalities were found on extensive diagnostic workup [Figure 1]c, [Figure 2]a, [Figure 2]b, [Figure 2]c and [Figure 3], [Figure 3]b, [Figure 3]c. CWs can be a risk factor for or the etiology of CS in young and adult patients. Therefore, he was started on antiplatelet therapy and a high dose of statin.{Figure 1}{Figure 2}{Figure 3}

 Discussion



A recent case--control study identified a statistically significant association between CW and ischemic strokes of unknown etiology in young adults and middle-aged patients. This single-center, case--control study found that the incidence of carotid artery webs in stroke patients was eight times higher than in the control group, suggesting that CW is one of the risk factors for ischemic stroke.[4] Sajedi et al. studied the epidemiology of CW and found that the incidence in patients with cryptogenic stroke was 21.1%. This data supports the relationship between CW and cryptogenic strokes.[5] However, the pathogenesis behind this relationship remains unknown. A retrospective controlled study of CW showed that patients with carotid artery stenosis of more than 70% may develop ischemic stroke as a result of insufficient perfusion.[6] However, there is a different mechanism behind CW and the formation of atherosclerotic plaques. Strokes caused by atherosclerotic plaques arise from plaque enlargement, which result in either carotid stenosis and intracranial hypoperfusion or intracranial artery embolization from plaque detachment.[4] Clarification of CW pathogenesis is needed to develop secondary preventions for ischemic stroke. Key imaging features and identifying characteristics of CW are as follows: (1) Due to its fast, high-resolution, and multiplanar reconstruction imaging, computed tomography angiogram has obvious advantages for characteristic imaging of CW and similar diseases such as carotid atherosclerosis and carotid dissection. Head and neck CTA is the first method of choice for initial clinical imaging.[7] In head and neck CTA sagittal images, CWs appear as thin intracavitary filling defects along the posterior wall of the carotid artery. In axial images, they are septal-like membrane structures in the carotid lumen. Color Doppler ultrasounds show tissue bands protruding into the lumen, carotid artery stenosis, or occlusion, as well as high flow turbulence and aliasing in the carotid artery, which is the manifestation of carotid stenosis.[8] (2) Imaging methods relevant to the identification of CWs are listed in [Table 1]. Carotid artery webs are a carotid vascular disease that is primarily identified by its clinical imaging features. It is important to distinguish this from other carotid vascular diseases, such as carotid artery dissection, traumatic aneurysm, and focal atherosclerotic plaque, and in situ carotid wall thrombosis.[6]{Table 1}

While CW is a possible risk factor for cryptogenic stroke, there is insufficient high-quality evidence-based data on its pathogenesis. It is crucial to understand its epidemiology and imaging features for early identification and stroke prevention.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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