Arterial tortuosity in patients with spontaneous cervical artery dissection

Association between cervicocerebral artery dissection and tortuosity - a review on quantitative and qualitative assessment

Cervicocerebral artery dissection stands out as a significant contributor to ischemic stroke in young adults. Several studies have shown that arterial tortuosity is associated with dissection. We searched Pubmed and Embase to identify studies on the association between arterial tortuosity and cervicocerebral artery dissection, and to perform a review on the epidemiology of cervicocerebral artery tortuosity and dissection, pathophysiology, measurement of vessels tortuosity, strength of association between tortuosity and dissection, clinical manifestation and management strategies. The prevalence of tortuosity in dissected cervical arteries was reported to be around 22%-65% while it is only around 8%-22% in non-dissected arteries. In tortuous cervical arteries elastin and tunica media degradation, increased wall stiffness, changes in hemodynamics as well as arterial wall inflammation might be associated with dissection. Arterial tortuosity index and vertebrobasilar artery deviation is used to measure the level of vessel tortuosity. Studies have shown an independent association between these two measurements and cervicocerebral artery dissection. Different anatomical variants of tortuosity such as loops, coils and kinks may have a different level of association with cervicocerebral artery dissection. Symptomatic patients with extracranial cervical artery dissection are often treated with anticoagulant or antiplatelet agents, while patients with intracranial arterial dissection were often treated with antiplatelets only due to concerns of developing subarachnoid hemorrhage. Patients with recurrent ischemia, compromised cerebral blood flow or contraindications for antithrombotic agents are usually treated with open surgery or endovascular technique. Those with subarachnoid hemorrhage and intracranial artery dissection are often managed with surgical intervention due to high risk of re-hemorrhage.

Recurrence of cervical artery dissection: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Cervical artery dissection (CAD) involving the carotid or vertebral arteries is an important cause of stroke in younger patients. The purpose of this systematic review is to assess the risk of recurrent CAD.

METHODS

A systematic review and meta-analysis was conducted on studies in which patients experienced radiographically confirmed dissections involving an extracranial segment of the carotid or vertebral artery and in whom CAD recurrence rates were reported.

RESULTS

Data were extracted from 29 eligible studies (n = 5898 patients). Analysis of outcomes was performed by pooling incidence rates with random effects models weighting by inverse of variance. The incidence of recurrent CAD was 4% overall (95% confidence interval (CI) = 3-7%), 2% at 1 month (95% CI = 1-5%), and 7% at 1 year in studies with sufficient follow-up (95% CI = 4-13%). The incidence of recurrence associated with ischemic events was 2% (95% CI = 1-3%).

CONCLUSIONS

We found low rates of recurrent CAD and even lower rates of recurrence associated with ischemia. Further patient-level data and clinical subgroup analyses would improve the ability to provide patient-level risk stratification.

Treatment and Outcomes of Cervical Artery Dissection in Adults: A Scientific Statement From the American Heart Association

Cervical artery dissection is an important cause of stroke, particularly in young adults. Data conflict on the diagnostic evaluation and treatment of patients with suspected cervical artery dissection, leading to variability in practice. We aim to provide an overview of cervical artery dissection in the setting of minor or no reported mechanical trigger with a focus on summarizing the available evidence and providing suggestions on the diagnostic evaluation, treatment approaches, and outcomes. Writing group members drafted their sections using a literature search focused on publications between January 1, 1990, and December 31, 2022, and included randomized controlled trials, prospective and retrospective observational studies, meta-analyses, opinion papers, case series, and case reports. The writing group chair and vice chair compiled the manuscript and obtained writing group members' approval. Cervical artery dissection occurs as a result of the interplay among risk factors, minor trauma, anatomic and congenital abnormalities, and genetic predisposition. The diagnosis can be challenging both clinically and radiologically. In patients with acute ischemic stroke attributable to cervical artery dissection, acute treatment strategies such as thrombolysis and mechanical thrombectomy are reasonable in otherwise eligible patients. We suggest that the antithrombotic therapy choice be individualized and continued for at least 3 to 6 months. The risk of recurrent dissection is low, and preventive measures may be considered early after the diagnosis and continued in high-risk patients. Ongoing longitudinal and population-based observational studies are needed to close the present gaps on preferred antithrombotic regimens considering clinical and radiographic prognosticators of cervical artery dissection.

Spontaneous cervical artery dissection: is it really a connective tissue disease? A comprehensive review

Background

Spontaneous cervical artery dissection (sCeAD) is an important cause of stroke in young adults. The underlying pathophysiology remains unclear, without validated biomarkers to identify subjects at risk. Previous studies suggested the role of abnormalities in the connective component of the arterial wall.

Purpose

To assess dermal ultrastructural aberrations of connective tissue by skin biopsy and genetic variations in sCeAD patients.

Method

We searched the PubMed and Scopus databases until August 2023 with PRISMA guidelines. Original articles assessing skin biopsy in sCeAD patients were included. Two reviewers independently conducted the screening.

Findings

We included 16 studies compromising 459 patients. Thirteen studies assessed ultrastructural changes and found aberrations of collagen and elastic fibers, described as irregular contours and calibers of collagen fibrils, composite flower-like fibrils, fragmented moth-eaten elastin, and microcalcifications, cumulatively in 50.5% of patients. Seven studies showed no causative mutations in collagen type I, III, V, or elastin genes. One study showed linkage between connective tissue alterations and mutation on chromosomes 15q2 and 10q26 using genome-wide linkage analysis, while another study found significant copy number variant enrichments in genes involved in extracellular matrix (COL5A2/COL3A1/SNTA1) and collagen fibril organizations (COL5A2/COL3A1). Finally, differential expression of extracellular proteins was linked to connective tissue disorder in patients with recurrent sCeAD using a quantitative proteomics approach.

Conclusion

Current literature supports the hypothesis that an underlying, subclinical connective tissue disorder, likely genetically determined, may predispose to arterial wall weakness and sCeAD. Further studies with larger sample sizes and robust methodology are needed to better define the role of connective tissue in sCeAD pathogenesis.

Unraveling the Links between Chronic Inflammation, Autoimmunity, and Spontaneous Cervicocranial Arterial Dissection

Advances in imaging techniques have led to a rise in the diagnosis of spontaneous cervicocranial arterial dissection (SCCAD), which is now considered a common cause of stroke in young adults. However, our understanding of the pathophysiological mechanisms underlying SCCAD remains limited. Prior studies have proposed various factors contributing to arterial wall weakness or stress as potential causes for SCCAD. A combination of biopsies, case reports, and case-control studies suggests that inflammatory changes and autoimmunity may play roles in the cascade of events leading to SCCAD. In this review, we examine the close relationship between SCCAD, chronic inflammation, and autoimmune diseases, aiming to explore potential underlying pathophysiological mechanisms connecting these conditions. While some relevant hypotheses and studies exist, direct evidence on this topic is still relatively scarce. Further investigation of the underlying mechanisms in larger clinical cohorts is needed, and the exploration of animal models may provide novel insights.

Review article: Non-penetrating neck artery dissection in young adults: Not to be missed!

Young adults who present to the ED with neck pain following non-penetrating, seemingly trivial trauma to the neck, are at risk of neck artery dissection and subsequent stroke. Sport-related neck injury is the chief cause. Physical examination may often be unremarkable, and although there may be reluctance to expose young patients to radiation, radiological imaging is central to making a diagnosis of arterial wall disruption. A comprehensive literature search was performed in relation to neck artery dissection, and the evidence was scrutinised. We discuss the typical mechanism of injury, symptoms, anatomical considerations and clinical aids in diagnosis of neck artery dissection. Although the incidence is low, neck artery dissection has a mortality of 7%. As such, it is important for front-line physicians to have a high suspicion of the diagnosis and a low threshold to organise radiological examinations, specifically computerised tomography. Early detection of neck artery dissection will trigger clinical protocols that call for multi-disciplinary team management of this condition. In general, guideline-based recommendation for the management of neck artery dissection involving an intimal flap is by anti-platelet therapy while treatment of neck artery dissection that results in a pseudo-aneurysm or thrombosis is managed by surgical intervention or endovascular techniques. Close follow up combined with antithrombotic treatment is recommended in these individuals, the goal being prevention of stroke.

Delayed Development of Aneurysmal Dilatations in Patients with Extracranial Carotid Artery Dissections

OBJECTIVE

Dissection of the carotid artery (CaAD) may result in aneurysm formation. The present study was undertaken to evaluate the time of onset of post-dissection extracranial carotid artery aneurysms (ECAA) following CaAD, and to analyse independent risk factors for the development of these aneurysms.

METHODS

From four European stroke centres, 360 patients with extracranial CaAD were included. The time between the estimated dissection onset and aneurysm formation was analysed, and the clinical risk factors increasing the probability of aneurysm were assessed.

RESULTS

The median duration of follow up was 5.2 months (range 0 - 24 months). A total of 75 post-dissection ECAAs were identified in 70 patients (19.4%, 95% confidence interval [CI] 15.7 - 23.8). In 52 of 70 (74%) patients, the ECAA was diagnosed at the initial clinical work up of CaAD diagnosis, with the median estimated time of dissection onset to ECAA diagnosis being six days (interquartile range [IQR] 0 - 25). In the remaining 18 (26%) patients who had normal carotid arteries at the initial imaging, the aneurysm diagnosis was made a median of 6.2 months (189 days) from the original imaging (IQR 128 - 198). A Cox proportional hazards model showed that both multiple artery dissections (hazard ratio [HR] 2.58, 95% CI 1.54 - 4.33) and arterial tortuosity (HR 1.79, 95% CI 1.08 - 2.95) were associated with presence of ipsilateral ECAA.

CONCLUSION

This post hoc cohort analysis showed substantially delayed development of ipsilateral ECAA in patients with CaAD, months after baseline. Multiple dissections and arterial tortuosity are associated with the presence of ECAA and can be used in future prediction models of ECAA development in patients with CaAD.

Carotid tortuosity is associated with extracranial carotid artery aneurysms

BACKGROUND

Tortuous arteries may be associated with carotid dissection. The intima disruption caused by a carotid dissection is a possible cause of extracranial carotid artery aneurysms (ECAAs). The aim was to investigate if carotid tortuosity is also associated with ECAA in patients without presence or history of a carotid artery dissection.

METHODS

A retrospective case-control study was performed including 35 unilateral ECAA patients (cases) and 105 age- and sex-matched controls. Tortuosity was expressed as tortuosity-index (TI), curvature, and torsion measured on computed tomography angiography (CTA) data in 3Mensio Vascular and MATLAB by two independent investigators. Primary comparison was tortuosity in ipsi- versus contralateral carotid artery within the cohort of ECAA patients. Secondary comparison was tortuosity with ipsilateral carotid arteries in control patients. All observations were assessed on inter- and intra-operator reproducibility.

RESULTS

Carotid tortuosity was comparable within the cohort of ECAA patients (Spearman correlation 0.76, P<0.001), yet distinctively higher in comparison with unilateral controls. After adjustment for patient characteristics, presence of ECAA was associated with TI (β 0.146, 95% CI: 0.100-0.192). All tortuosity observations showed excellent inter- and intra-operator reproducibility.

CONCLUSIONS

Carotid tortuosity seems to be a risk factor for development of ECAA. Surveillance of individuals with increased carotid tortuosity therefore potentially ensures prompt diagnosis and treatment of ECAA. However, future research should investigate if persons with an increased tortuosity do indeed develop ECAA.

Arterial Tortuosity and Its Correlation with White Matter Hyperintensities in Acute Ischemic Stroke

Introduction

The association between arterial tortuosity and acute ischemic stroke (AIS) has been reported, but showing inconsistent results. We hypothesized that tortuosity of extra- and intracranial large arteries might be higher in AIS patients. Furthermore, we explored the correlation between artery tortuosity and white matter hyperintensity (WMH) severity in AIS patients.

Methods

166 AIS patients identified as large artery atherosclerosis, and 83 control subjects were enrolled. All subjects received three-dimensional computed tomography angiography (CTA). Arterial tortuosity was evaluated using the tortuosity index. WMHs were evaluated using magnetic resonance imaging in all AIS patients.

Results

AIS patients showed significantly increased arterial tortuosity index relative to controls, including left carotid artery (CA) (p = 0.001), right CA (p < 0.001), left common carotid artery (CCA) (p < 0.001), right CCA (p < 0.001), left internal carotid artery (p = 0.001), right internal carotid artery (p = 0.01), left extracranial internal carotid artery (EICA) (p < 0.001), right EICA (p = 0.01), and vertebral artery dominance (VAD) (p = 0.001). The tortuosity of all above arteries was associated with the presence of AIS. AIS patients with moderate or severe WMHs had a higher tortuosity index in left CA (p = 0.005), left CCA (p = 0.003), left EICA (p = 0.07), and VAD (p = 0.001). In addition, the tortuosity of left EICA and VAD was associated with WMH severity in AIS patients.

Conclusions

Increased extra- and intracranial large arteries tortuosity is associated with AIS. The tortuosity of left carotid artery system and vertebral artery may be the independent risk factors for WMH severity in AIS patients. Clinical Trial Registration. This trial is registered with NCT03122002 (http://www.clinicaltrials.gov).

Association between carotid artery dissection and vascular tortuosity: a case-control study

PURPOSE

We aimed to verify if vascular tortuosity (VT) may represent a risk factor for spontaneous epiaortic vessel dissection (sEVD) in young adult patients.

METHODS

We identified 304 patients aged under 55 years consecutively admitted for acute cerebrovascular events to our Stroke Unit. After checking the possibility to perform a 3D reconstruction of epiaortic vessels on CT-angiography images, we selected and compared fifty patients with sEVD (cases) with fifty-one patients without dissection (controls). VT of carotid and vertebral arteries was measured on reconstructions evaluating the vascular tortuosity index (VTI), calculated according to a specific algorithm, and the presence of kinking and coiling. Differences between groups were analyzed by Student-t test for numeric variables and chi-square test for categoric ones. A ROC curve analysis was used to look for a VTI threshold value beyond which the risk of dissection was significantly increased.

RESULTS

VTI was significantly higher in cases than in controls only considering carotid arteries (p = 0.029); cases did not have a significantly higher rate of kinking and coiling than controls (p = 0.059 and 0.077, respectively). We have found a significant VTI threshold value of 27.9% (under curve area = 61.6%, p = 0.04) only for carotid artery dissection.

CONCLUSION

VT appears to be associated with an increased risk of dissection for the carotid district but not for the vertebral one. The different structure, embryogenesis, and pathophysiology of dissection between the two districts could explain this finding. VTI threshold as carotid artery dissection predictor deserves confirmation in larger studies.

Utility of Pipeline embolization device for emergency recanalization of a dissecting carotid tonsillar loop: illustrative cases

BACKGROUND

Cervical arterial tortuosity is not uncommon in patients with spontaneous carotid artery dissections (CADs), but the tortuosity often precludes endovascular stent reconstruction. The authors report 2 cases of emergency recanalization of a carotid tonsillar loop dissection using a Pipeline embolization device (PED).

OBSERVATIONS

Two patients presented with symptomatic CAD involving tonsillar looping of the cervical internal carotid artery (ICA). Although the tonsillar loop prevented navigation of the carotid and peripheral stent delivery system, a PED was easily navigated and successfully deployed, resulting in successful recanalization of a looped ICA.

LESSONS

Emergency recanalization of a cervical CAD using a PED is a feasible alternative for treating a cervical CAD associated with tonsillar loops.

Increased Internal Carotid Artery Tortuosity is a Risk Factor for Spontaneous Cervicocerebral Artery Dissection

OBJECTIVE

Spontaneous cervicocerebral artery dissection (sCCD) is an important cause of ischaemic stroke that often occurs in young and middle aged patients. The purpose of this study was to investigate the correlation between tortuosity of the carotid artery and sCCD.

METHODS

Patients with confirmed sCCD who underwent computed tomography angiography (CTA) were reviewed retrospectively. Age and sex matched patients having CTA were used as controls. The tortuosity indices of the cervical arteries were measured from the CTA images. The carotid siphon and the extracranial internal carotid artery (ICA) were evaluated according to morphological classification. The carotid siphons were classified into five types. The extracranial ICA was categorised as simple tortuosity, coiling or kinking. Independent risk factors for sCCD were investigated using multivariable analysis.

RESULTS

The study included sixty-six patients with sCCD and 66 controls. There were no differences in vascular risk factors between the two groups. The internal carotid tortuosity index (ICTI) (25.24 ± 12.37 vs. 15.90 ± 8.55, respectively; p < .001) and vertebral tortuosity index (VTI) (median 11.28; interquartile range [IQR] 6.88, 18.80 vs. median 8.38; IQR 6.02, 12.20, respectively; p = .008) were higher in the patients with sCCD than in the controls. Type III and Type IV carotid siphons were more common in the patients with sCCD (p = .001 and p < .001, respectively). The prevalence of any vessel tortuosity, coiling and kinking of the extracranial ICA was higher in the patients with sCCD (p < .001, p = .018 and p = .006, respectively). ICTI (odds ratio [OR] 2.964; p = .026), VTI (OR 5.141; p = .009), and Type III carotid siphons (OR 4.654; p = .003) were independently associated with the risk of sCCD.

CONCLUSION

Arterial tortuosity is associated with sCCD, and greater tortuosity of the cervical artery may indicate an increased risk of arterial dissection.

Changes in internal carotid and vertebral arterial wall stiffness with head movement can be detected with shear wave elastography

Background: Safe practice is important for patients with neck pain, with the potential for injury to cervical arteries. Cervical manipulation or end range techniques/positions may place considerable strain on the arteries. Altered integrity of the arterial wall may render them more susceptible to minor trauma, particularly in the upper cervical region. Screening of blood flow velocity is limited for predicting those at risk. Examining properties of the cervical arterial wall (stiffness characteristics) and their response to head movement may provide an alternate measure of arterial susceptibility.Objectives: To investigate whether shear wave ultrasound elastography can detect any changes in internal carotid (ICA) and vertebral (VA) arterial wall stiffness in neutral compared with contralateral head rotation.Design: Observational studyMethods: Shear wave ultrasound elastography was used to measure the stiffness of the ICA and VA. Shear wave velocity (m/s), indicative of arterial stiffness, was measured in both arteries proximally (C3-4) and distally (C1-2) in neutral and contralateral head rotation as were intimal thickness (mm) and flow velocity (cm/s).Results: Thirty participants (20-62 years) were successfully imaged. The VA was stiffer than ICA and it became significantly stiffer in contralateral rotation (p = 0.05). The ICA became significantly less stiff (p = 0.01). Effects were more apparent at C1-2 but significant in the ICA only (p = 0.03). Flow velocity and intimal thickness were unchanged in rotation.Conclusions: Changes in VA and ICA arterial wall stiffness can be measured with shear wave ultrasound elastography. This measure may ultimately help identify arteries with greater vulnerability to rotational stresses.

Association between Extracranial Carotid Artery Tortuosity and Clinical Outcomes in Anterior Circulation Acute Ischemic Stroke without Undergoing Endovascular Treatment

BACKGROUND

Extracranial carotid artery (ECA) tortuosity may influences successful recanalization rates of mechanical thrombectomy in acute ischemic stroke (AIS), yet the relationship between ECA tortuosity and the prognosis of patients with anterior circulation AIS who cannot undergo endovascular treatment remains uncertain. We hypothesized that increased tortuosity of the ECA leads to unfavorable outcomes in such patients.

METHODS

Patients with anterior circulation AIS who underwent computed tomography angiography of the head and neck in our hospital between March 2018 and November 2018 were retrospectively analyzed. The tortuosity of the bilateral ECA was measured, and functional outcomes were evaluated by a modified Rankin Scale (mRS) at 90 days. Multivariate logistic regression models were used to determine the association between ECA tortuosity and outcomes of patients.

RESULTS

A total of 203 patients were enrolled in our study, including 140 patients (68.97%) with favorable outcomes (mRS, 0-2) and 63 patients (31.03%) with unfavorable outcomes (mRS, 3-6). After adjusting for age, atrial fibrillation, stroke territory, and posthospital antithrombotics/statins therapy in multivariate logistic regression model I, ECA tortuosity (odds ratio, 1.052; 95% confidence interval, 1.010-1.096; P = .015) was an independent risk of unfavorable outcomes in enrolled patients. In the other 2 models (II and III) which adjusted for age, sex, baseline National Institutes of Health Stroke Scale score, and with or without posthospital medication, ECA tortuosity was also showed independent relationship to unfavorable outcomes. The optimal cutoff was 12.5 to predict the unfavorable outcomes in a receiver operating characteristic curve.

CONCLUSIONS

Our study demonstrated that the ECA tortuosity is an independent predictor of unfavorable outcomes for anterior circulation AIS patients who without undergoing endovascular treatment after hospital admission. ECA tortuosity values greater than 12.5 may indicate an unfavorable outcome.

Comparability of semiautomatic tortuosity measurements in the carotid artery

Purpose

Increased arterial tortuosity has been suggested as a predisposing factor for carotid artery dissection, which is an important risk factor for development of extracranial carotid artery aneurysms (ECAA). Prior to comparison with non-ECAA controls, the optimal measurement technique should be defined. This study describes the difference between software packages in terms of reproducibility and absolute outcome of arterial tortuosity measurements in ECAA patients.

Methods

CT-angiography analysis was performed on 12 ECAA patients selected from our registry, using four software packages: 3mensio Vascular, TeraRecon, Vital Images, and Aycan OsiriX PRO. The tortuosity index (TI) was calculated from the skull base until the carotid bifurcation and aortic arch, and was defined as the centerline’s true length divided by the straight line distance. Intraclass correlation coefficients (ICC) with 95% confidence intervals were calculated to quantify inter- and intra-observer variability within one software package, and differences in measured TI between packages.

Results

Inter-observer agreement was nearly perfect for 3mensio, excellent for Vital Images and OsiriX, and substantial for TeraRecon, with ICC 0.99 (0.96–1.0), 0.90 (0.69–0.97), 0.84 (0.53–0.95), and 0.72 (0.28–0.91), respectively. Intra-observer agreement ranged from ICC 1.0 for 3mensio to 0.91 for TeraRecon. Agreements in TI ranged from ICC 0.99 (0.98–1.0) for 3mensio vs. OsiriX, to 0.95 (0.82–0.98) for 3mensio vs. TeraRecon. Median time needed to complete one round of measurements was highest for OsiriX (p = 0.013).

Conclusions

Carotid artery tortuosity measurements are reproducible and comparable between current commercially available software packages, with high intra-observer agreement. Although the reproducibility differed per software packages, all packages scored an acceptable inter-observer agreement.

Cervical artery dissection after sports - An analytical evaluation of 190 published cases

Introduction

Cervical artery dissections may be preceded by mechanical trigger events, often related to sports.

Methods

Using the MEDLINE database, we identified case reports and case series of sports-related cervical artery dissections. Information of the type of sport, age and gender of the patient, affected vessels, associated infarction, time delay, and neurological sequelae were extracted. Demographic and clinical characteristics were compared between sport groups using analysis of variance and Chi square tests. Differences were further assessed with adjusted post hoc tests and homogenous subsets.

Results

A total of 115 reports describing 190 patients with cervical artery dissections related to 45 different sports were identified. The mean age of all patients was 35 years; 26% of all patients were women. Anterior and posterior circulation, as well as left and right side were affected with similar frequency. Patients belonging to different sport categories differed significantly with regard to age (p < 0.001), gender (p < 0.001), and affected circulation (anterior vs. posterior, p = 0.02). The posterior circulation was most often affected in golf players (88%) and least often in individuals engaging in exercise (23%) and scuba divers (29%). Laterality (left vs. right) and mortality were similar between sport groups.

Discussion

We performed a comprehensive review and analytical evaluation of case reports describing patients with cervical artery dissections after sport. Confirmation of our findings in prospective studies is needed.

Conclusion

Cervical artery dissection has been described in relation to a wide variety of sports. The risk of injury to particular neurovascular structures may depend on the type sport involved. Discipline-specific incidence rates are not known.