Intracranial and extracranial arterial dissection presenting with ischemic stroke: Lesion location and stroke mechanism

Behavior of Extracranial-to-Intracranial Extended Arterial Dissections of the Vertebral Artery

BACKGROUND

Vertebral artery dissections (VADs) may extend from the extracranial to the intracranial vasculature (e+iVAD). We evaluated how the characteristics of e+iVAD differed from those of intracranial VAD (iVAD).

METHODS AND RESULTS

From 2002 to 2019, among consecutive patients with cervicocephalic dissection, those with iVAD and e+iVAD were included, and their clinical characteristics were compared. In patients with unruptured dissections, a composite clinical outcome of subsequent ischemic events, subsequent hemorrhagic stroke, or mortality was evaluated. High-resolution magnetic resonance images were analyzed to evaluate intracranial remodeling index. Among 347 patients, 51 (14.7%) had e+iVAD and 296 (85.3%) had iVAD. The hemorrhagic presentation occurred solely in iVAD (0.0% versus 19.3%), whereas e+iVAD exhibited higher ischemic presentation (84.3% versus 27.4%; P<0.001). e+iVAD predominantly presented steno-occlusive morphology (88.2% versus 27.7%) compared with dilatation patterns (11.8% versus 72.3%; P<0.001) of iVAD. The ischemic presentation was significantly associated with e+iVAD (iVAD as a reference; adjusted odds ratio, 3.97 [95% CI, 1.67-9.45]; P=0.002]). Patients with unruptured VAD showed no differences in the rate of composite clinical outcome between the groups (log-rank, P=0.996). e+iVAD had a lower intracranial remodeling index (1.4±0.3 versus 1.6±0.4; P<0.032) and a shorter distance from dural entry to the maximal dissecting segment (6.9±8.4 versus 15.7±7.4; P<0.001).

CONCLUSIONS

e+iVAD is associated with lower rates of hemorrhages and higher rates of ischemia than iVAD at the time of admission. This may be explained by a lower intracranial remodeling index and less deep intrusion of the dissecting segment into the intracranial space.

Obesity in acute ischaemic stroke patients treated with intravenous thrombolysis therapy

OBJECTIVES

This article aimed to analyze the relationship between obesity and the efficacy of acute ischaemic stroke patients treated with IVT.

BACKGROUND

Stroke causes morbidity and mortality in large numbers of individuals annually. Intravenous thrombolysis (IVT)with recombinant tissue plasminogen activator (r-tPA) is currently the only approved by the FDA for treatment of acute ischaemic stroke. Researchers have focused on studying the mechanisms associated with ischaemic stroke. Obesity is an established vascular risk factor with increasing prevalence and a huge impact on public health worldwide. It is an independent predictor for ischaemic stroke with a 4% risk increase for each unit augmentation in body mass index (BMI). Therefore, obese patients will constitute an increasing subgroup of candidates for IVT. However, its impact on prognosis in acute ischaemic stroke patients with intravenous thrombolysis did not reach a consensus conclusion.

METHODS

Systematic literature search of PUBMED databases published before August 2020, was performed to identify studies addressing the role of obesity in acute ischaemic stroke patients treated with IVT. Studies included randomized clinical trials, observational studies, guideline statements, and review articles.

CONCLUSIONS

Obesity may be related to long-term prognosis of large group of AIS patients treated with IVT. It depends on the scale of clinical study samples, follow-up time, and evaluation criteria.

Parent artery occlusion for cerebral infarction after spontaneous recanalization in traumatic vertebral artery: A case report

Background

There is no established treatment strategy for traumatic vertebral artery occlusion that does not require cervical spine repair surgery.

Case Description

A 49-year-old man was brought to our hospital with traffic trauma. Fractures were observed in the left lateral mass and transverse process of Atlas and the left vertebral artery was occluded at the level of the foramen transversum of Atlas. No acute cerebral infarction was observed. Because the cervical spinal cord was not compressed by the fracture, no repair surgery was performed. Continuous intravenous heparin and oral aspirin were started for traumatic vertebral artery occlusion. Thereafter, the left vertebral artery spontaneously recanalized, but no cerebral infarction was observed. The patient was discharged home on day 16 of injury. Four days later, however, he was brought to our hospital with nausea and lightheadedness. Acute cerebral infarction was observed in the left posterior inferior cerebellar artery territory and a thrombus in the left vertebral artery V4 segment. Parent artery occlusion was performed to prevent further cerebral infarction due to distal embolization of the thrombus. No further cerebral infarction occurred after the operation and the patient was discharged home with a modified Rankin scale score of 1.

Conclusion

In cases of traumatic vertebral artery occlusion without an occlusive mechanism, parent artery occlusion may be considered in terms of recanalization risk, regardless of the need for repair surgery.

Current Treatment Results of Intracranial Carotid Artery Dissection Causing Cerebral Ischemia: A Japanese Nationwide Survey

Intracranial carotid artery dissection causing cerebral ischemia is a rare but important cause of cerebral infarction in children and adolescents. Although endovascular therapy has been reported to be effective, questions regarding the indications for intervention are yet to be addressed. Therefore, this study aimed to evaluate factors related to clinical outcomes through a nationwide survey. Overall, 35 neurosurgical centers reported patients within 2 weeks after ischemic onset due to intracranial carotid artery dissection causing cerebral ischemia treated between January 2015 and December 2020. Data on clinical and radiological findings were statistically analyzed. Twenty-eight patients met the inclusion criteria. The median age was 36 years (range, 7-59 years), without sex differences. Headache at onset was documented in 60.7% of the patients. Dissection findings were categorized into stenosis (71.4%) or occlusion (28.6%). Initial treatments, including various antithrombotic agent combinations in 23 (82.1%) patients, effectively improved or prevented aggravation in half of the patients. The patients with stenotic dissection were significantly more likely to experience aggravation during the initial treatment than did those with occlusive dissection (P = 0.03). In addition, the patients with moderate to severe neurological deficits on admission had poorer outcomes at discharge more frequently than did those with mild neurological deficits on admission. Eight patients undergoing endovascular therapy had no procedural complications or further aggravation after intervention. In conclusion, patients with intracranial carotid dissection causing cerebral ischemia who had a stenotic dissection were at risk of further aggravation, and endovascular therapy effectively improved or prevented aggravation.

Interplay between carotid artery dissection and thrombophilia leading to ischaemic stroke after minor head trauma in an adolescent: a case report

Stroke in children is more common than is often realised; there are numerous potential causes, including carotid artery injury resulting from minor head or neck trauma, as well as genetic conditions associated with thrombophilia. A 13-year-old boy suffered an arterial ischaemic stroke (AIS) secondary to dissection of the left internal carotid artery (ICA) after he headed the ball during a game of football. He presented with generalised tonic-clonic seizure, loss of consciousness, right-sided hemiplegia and aphasia. Neuroradiological imaging showed left caudate, putaminal and posterior insular ischaemic infarct secondary to complete occlusion of the left ICA and accompanying partial left middle cerebral artery occlusion. He was treated with anticoagulant and anti-aggregant agents. Rarely, minor head trauma can result in internal carotid artery dissection, thrombus formation and arterial occlusion, leading to arterial ischaemic stroke. Prompt diagnosis and management are crucial to achieve a good neurological outcome.Abbreviations: AIS: arterial ischaemic stroke; ANA: anti-nuclear antibody; APA: anti-phospholipid antibody; APTT: activated partial thromboplastin time; CAD: carotid artery dissection; CCAD: cranio-cervical artery dissection; CRP: C-reactive protein; CT: computed tomography; CTA: computed tomography angiography; dsDNA: double-stranded DNA; ESR: erythrocyte sedimentation rate; ICA: internal carotid artery; LA: lupus anticoagulant; MCA: middle cerebral artery; MRA: magnetic resonance angiography; MRI: magnetic resonance imaging; MTHFR: methylenetetrahydrofolate reductase; PT INR: prothrombin time international normalised ratio.

Acute internal carotid artery occlusion due to dissection of the paraclinoid segment: Diagnostic usefulness of angiographic findings during stent retriever deployment

Intracranial artery dissection is an uncommon but possible cause of ischemic stroke, and is usually diagnosed based on imaging findings such as mural hematoma and dissection flap. However, it is challenging to recognize the underlying dissection in cases of acute large vessel occlusion. In this report, we present a case of acute internal carotid artery occlusion, in which the underlying dissection of the paraclinoid segment was found during the thrombectomy procedure. Two thrombectomy procedures failed to recanalize the acute internal carotid artery occlusion without removing any clot. Angiography performed during a Trevo stent retriever deployment in the first pass showed obscure contrast defects in the stent strut with temporary flow restoration. In the next pass, the appearance of the contrast defects changed and a parallel linear contrast appeared on the outside of the vessel wall. These angiographic findings were identified as mural hematoma and dissection flap, indicating dissection of the paraclinoid as the cause of the occlusion. During antiplatelet loading and preparation of a dedicated intracranial stent, the Trevo stent retriever was left deployed again at the occlusion site to maintain the blood flow. After permanent stenting with an Enterprise stent, angiography revealed complete recanalization. The patient recovered fully after the procedure. In the present case, stent retriever deployment revealed the hallmarks of dissection on angiography, such as mural hematoma, dissection flap, and temporal morphological changes, by restoring the blood flow temporarily. Such angiographic findings can provide useful information on the occlusion characteristics and real-time feedback for optimal treatment strategy.

Trends in admissions for intracranial dissections in the United States

INTRODUCTION

Intracranial artery dissection (IAD) is rarer than cervical artery dissections (CeAD), and information is based on limited series with small cohorts. There are only several small-scale studies attempting to characterize the natural history of the disease. Herein, we analyze the prevalence of IADs in hospitalized patients using a national database.

METHODS

The National Inpatient Sample was queried from 2016-2019 for patients with a diagnosis of unruptured intracranial dissection (uIAD) using ICD-10-CM codes (I67.0). Moreover, patients with acute ischemic stroke (AIS) and CeAD were extracted to compare its prevalence among patients with concomitant AIS (+/-dissections). The Cochrane-Armitage test was conducted to assess trends in the prevalence of uIADs among those with concomitant AIS or among all craniocervical dissections.

RESULTS

There were 725 hospitalizations involving uIAD, while there were 62,220 involving CeADs. uIADs represented 5.1 per million hospitalizations across 2016-2019. The average age of presentation was 56.9 years (SE: 1.62), while it was 54.4 (SE: 0.17) for CeADs (p = 0.13). Females were represented among 44.8% (n = 325) of uIADs, a similar proportion compared to CeADs (44.3%%, n = 27,530; p = 0.89). Compared to CeADs, AIS and motor deficits were more common in uIAD (71.72% vs. 47.0%; p < 0.001). There were 18.6 uIAD with concomitant AIS per 100,000 with AIS. uIADs represented 1.75% of all dissections with concomitant AIS (n = 520/29,750). There was no trend in the average age of presentation for uIADs. Proportion of females among those with uIADs increased from 36.8% in 2016 to 59.5% in 2019 (trend: +9.46% per year; 95% CI: 3.13 to 15.8; p = 0.004). There was no trend in the proportion of races among those with uIADs.

CONCLUSION

The prevalence of uIADs among hospitalized patients is very low, and only 1.75% of craniocervical dissection-related AIS is due to uIAD. Compared to CeADs, patients were more likely to be male, and uIAD more commonly led to acute ischemic stroke and motor deficits. The trend in age remained stable across the four years analyzed, while the proportion of females increased. There was no trend in the proportion of races among uIADs, however.

Usefulness of Ultrasonography in the Diagnosis and Follow-up of Extracranial Vertebral Artery Dissection

Extracranial vertebral artery dissection is a cerebrovascular disease that occurs most commonly in young people. A 32-year-old man experienced sudden cervical pain and was diagnosed with left vertebral artery dissection after arterial changes were identified by ultrasonography. The reduction in the size of an intramural hematoma in the left vertebral artery and in the peak systolic velocity were evaluated over time. Computed tomography, magnetic resonance imaging, and cerebral angiography are generally performed to diagnose and follow-up extracranial vertebral artery dissection; however, carotid ultrasonography has an advantage over these modalities by enabling the simultaneous observation of vascular morphology and hemodynamics.

Clinical Manifestation and Radiologic Patterns of Spontaneous Cervicocephalic Dissection According to the Anatomic Location: A Single-Center Analysis in Korean Patients

PURPOSE

Spontaneous cervicocephalic dissection (SCAD) is an important cause of stroke and shows various lesion locations and clinical features. The purpose of this study was to analyze the location of SCAD and its clinical and radiologic patterns in Korean patients.

MATERIALS AND METHODS

Patients with SCAD who were evaluated between 2013 and 2018 at a tertiary center in Korea were reviewed. We classified and compared the morphological (aneurysm or steno-occlusion) and presenting (hemorrhage or infarction) patterns according to the lesion locations (anterior circulation [AC] vs. posterior circulation [PC]; intradural [ID] vs. extradural [ED]).

RESULTS

A total of 166 patients were included in this study. The SCAD most commonly occurred in the PC-ID location (65.1%), followed by AC-ID (13.3%), AC-ED (13.3%), and PC-ED (8.4%). Aneurysm and steno-occlusion patterns were observed in 66.9% and 57.8% of the cases, respectively. The aneurysm pattern was significantly more common in the PC-ID location (78.7%) than in other locations. As for the presenting pattern, cerebral infarction was the most common pattern (39.8%), and intracranial hemorrhage was observed only in the ID location (7.2%).

CONCLUSION

In Korean patients, PC-ID, especially ID vertebral artery, was the most common location of SCAD, and most cases were accompanied by an aneurysm. It also suggested that these location trends differ by population or ethnicity.

Isolated posterior inferior cerebellar artery dissection with ischaemic stroke: evaluating the radiological features and diagnostic feasibility of high-resolution vessel wall imaging

AIM

To evaluate the radiological features of isolated posterior inferior cerebellar artery dissection (PICAD) and the feasibility of using high-resolution vessel-wall imaging (HR-VWI) for diagnosing PICAD.

MATERIALS AND METHODS

Three hundred and nine patients with arterial dissection involving the posterior cerebral circulation, who underwent HR-VWI between March 2012 and July 2019 were reviewed retrospectively. Among them, 44 patients (14.2%) were diagnosed with isolated PICAD in consensus among a neuroradiologist, a neurointerventionist, and a neurologist. Two neuroradiologists reviewed the vessel wall images independently for evidence of dissection (dissection flap, outer diameter enlargement on T2-weighted imaging [WI], mural haematoma). Diagnostic confidence was also scored on a five-point scale. Intra- and interobserver agreement for diagnosing PICAD and detecting evidence of dissection were evaluated.

RESULTS

Dissection flaps were seen on T2WI in all cases (100%) and on contrast-enhanced T1WI in 34 patients (79.1%). Outer diameter enlargement of the steno-occlusive lesions on angiography was detected in most cases (97.7%). A mural haematoma was detected on three-dimensional (3D) contrast-enhanced motion-sensitised driven-equilibrium T1WI in 97.1% of the cases. The mean diagnostic confidence score derived by two neuroradiologists was 4.72. The two reviewers showed substantial to almost perfect agreement (weighted kappa coefficient: 0.62-0.97).

CONCLUSION

Use of HR-VWI as a diagnostic tool for PICAD is feasible, and a dissection flap with outer wall enlargement on HR-T2WI allows confident dissection diagnosis. The present data suggest that PICAD might be considered as a stroke aetiology in patients with unexplained ischaemic stroke in the PICA territory, and that PICA evaluation with HR-VWI is both necessary and feasible.

A review of carotid and vertebral artery dissection

Cervical artery dissection is a major cause of ischaemic stroke in young adults. The diagnosis can be challenging as some patients may present with seemingly benign symptoms such as a headache, neck pain or dizziness. However, the neurological sequelae of a transient ischaemic attack, vision loss or ischaemic stroke are potentially devastating. All hospital clinicians must be able to recognise this diagnosis and organise timely and appropriate investigations as antithrombotic treatment reduces the risk of stroke recurrence. This article reviews the literature to provide practical information for clinicians to recognise key risk factors and features of history and examination which should raise suspicion of cervical artery dissection. Diagnosis can now be made using the non-invasive, commonly available modalities of computed tomography angiography or magnetic resonance angiography. Timely treatment with antithrombotic agents is recommended to reduce the rate of an ischaemic stroke.

High-resolution magnetic resonance imaging for the follow-up of intracranial arterial dissections

High-resolution magnetic resonance imaging (HRMRI) with a 3-T system can be utilized to identify intracranial arterial dissections (ICADs) as it reveals more than three key features with better clarity than other conventional imaging modalities. This study aimed to assess the changes in the key features of ICADs on HRMRI over time. We screened patients who had undergone HRMRI within 7 days of symptom onset for the evaluation of characteristics associated with intracranial steno-occlusive lesions. Among them, patients who (1) were diagnosed with ICAD based on HRMRI findings and (2) underwent follow-up HRMRI 3-12 months after the initial HRMRI were included in the final study. Baseline HRMRI revealed an intramural hematoma, a flap, and a double lumen in 17 (100%), 15 (88%), and 10 (59%) individuals, respectively. At the 3-months follow-up, an intramural hematoma was still observed in two patients; however, there were various changes in the double lumen and intimal flap. At the 6-months follow-up, an intramural hematoma was not observed in most patients, whereas the double lumen and intimal flap persisted in most patients. The 9-months follow-up displayed distinct differences from the initial status, whereas the 12-months follow-up exhibited no intramural hematomas, intimal flaps, or double lumens in most patients. In those with ICAD, radiological changes were observed between the initial HRMRI and subsequent HRMRI. Moreover, typical ICAD features were hardly retained at the 1-year follow-up. These changes might reflect dynamic processes, including the healing state of the patients.

Emergent stenting after intravenous thrombolysis for isolated basilar artery dissection in a patient with acute ischemic stroke: a case report

Background

Isolated basilar artery dissection (IBAD) is a rare but important cause of ischemic stroke. Anti-thrombotic therapy is often used to treat IBAD-related ischemic stroke, but selected cases might need more aggressive treatment. There is no previous report of emergent stenting for IBAD-related ischemic stroke after intravenous thrombolysis.

Case presentation

A 53-year-old Japanese woman was admitted to our hospital with disturbance of consciousness, right hemiplegia, severe dysarthria, and total gaze paralysis. Brain magnetic resonance imaging revealed no ischemic lesion, but magnetic resonance angiography showed stenosis in the basilar artery. After initiation of intravenous thrombolysis, her neurological symptoms dramatically improved. Five hours later, however, her symptoms deteriorated again. Cerebral angiography showed IBAD. Emergent stenting was successfully performed. At 90 days after stroke onset, she had no significant disability, with a modified Rankin scale score of 1.

Conclusions

Emergent stenting can be an effective treatment for patients with IBAD-related ischemic stroke who are resistant to IV-rtPA.

Imaging of Non-atherosclerotic Vasculopathies

Non-atherosclerotic vasculopathies (NAVs) may present with various neurological symptoms ranging from headache, stroke, visual symptoms, and various types of intracranial hemorrhage. NAVs result from different etiologies which include collagenopathies, immunological, hematological, and infection mechanisms, and other rarer unidentifiable or idiopathic causes. NAV etiologies account for about 10–15% and 20–25% of adult and pediatric stroke cases, respectively, and therefore, diagnosing the underlying cause of NAV becomes clinically very important. Clinical diagnosis of NAV is challenging because the clinical presentation is very non-specific and overlapping with various other central nervous system disorders. Before the advent of non-invasive techniques, making a diagnosis of non-atherosclerotic vasculopathy as a cause of the stroke was very challenging. Today with newer techniques such as high-resolution magnetic resonance (MR), MR and computed tomography perfusion, and angiogram, there are number of pointers which can give us a lead about the non-atherosclerotic causes. Imaging may provide the first lead to the clinician regarding the diagnosis or possible differential diagnosis so that the targeted and focused biomarkers (blood, cerebrospinal fluid, or/and in some cases biopsies) may be obtained to clinch the diagnoses. The purpose of the article is to enumerate the causes, clinical features, and illustrate the imaging findings of the various non-atherosclerotic vasculopathic disorders and discuss “pearls” to their diagnosis. In this article, we have also discussed the latest advances in vascular imaging and elaborated on few uncommon non-atherosclerotic vasculopathies. These are very relevant clinically in the day-to-day practice for the radiologist, neurologist, and the neurointerventionalist.

Hemichorea-hemiballismus as the initial manifestation of symptomatic middle cerebral artery dissection: A case report

INTRODUCTION

Hemichorea-hemiballismus, which spans a spectrum of involuntary, continuous, nonpatterned movement involving one side of the body, can emerge as the initial manifestation of acute ischemic stroke. However, because of its rarity in the community, the diagnosis and treatment are often delayed.

PATIENT CONCERNS

We report a unique case of a 47-year-old female who presented with acute onset hemichorea-hemiballismus. No obvious focal sign apart from involuntary, continuous, nonpatterned movement of her left arm and leg was presented.

DIAGNOSIS

Initial diffusion-weighted magnetic resonance imaging (MRI) was negative but significant increase of blood flow velocity in the right middle cerebral artery (MCA) stem was revealed by transcranial doppler sonography. Repeated MRI showed acute infarction in the contralateral globus pallidus. Isolated dissection of the right MCA typified by intimal flap with double lumen was identified by digital subtraction angiography and high-resolution magnetic resonance imaging (HR-MRI).

INTERVENTIONS

The patient was initially treated with dual antiplatelet agents but the uncontrollable movement deteriorated during hospitalization. Antithrombotic therapy was then intensified with combination of tirofiban and low-molecular-weight heparin. Other symptomatic treatment included volume expansion with colloidal fluid to improve cerebral perfusion. Her involuntary movement gradually diminished and the patient was discharged with rivaroxaban 15 mg/daily.

OUTCOMES

The patient had recovered with significant reduction in her hemichorea-hemiballismus. Three-month follow-up HR-MRI showed complete resolution of the MCA dissection lesions.

CONCLUSION

Prompt recognition of acute onset hemichorea-hemiballismus as the manifestation of acute ischemic stroke in appropriate clinical setting may reduce diagnostic delay. Multiple imaging techniques including cerebral digital subtraction angiography and HR-MRI can be applied to diagnosis and further clarify the mechanism of stroke, which facilitate in selection of secondary prevention therapies.

Qualitative Assessment and Reporting Quality of Intracranial Vessel Wall MR Imaging Studies: A Systematic Review

BACKGROUND

Over the last quarter-century, the number of publications using vessel wall MR imaging has increased. Although many narrative reviews offer insight into technique and diagnostic applications, a systematic review of publication trends and reporting quality has not been conducted to identify unmet needs and future directions.

PURPOSE

We aimed to identify which intracranial vasculopathies need more data and to highlight areas of strengths and weaknesses in reporting.

DATA SOURCES

PubMed, EMBASE, and MEDLINE databases were searched up to September 2018 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.

DATA ANALYSIS

Two independent reviewers screened and extracted data from 128 articles. The Strengthening the Reporting of Observational Studies in Epidemiology guidelines were used to assess the reporting quality of analytic observational studies.

DATA SYNTHESIS

There has been an exponentially increasing trend in the number of vessel wall MR imaging publications during the past 24 years (P < .0001). Intracranial atherosclerosis is the most commonly studied intracranial vasculopathy (49%), followed by dissections (13%), aneurysms (8%), and vasculitis (5%). Analytic observational study designs composed 48% of the studies. Transcontinental collaborations showed nonsignificantly higher reporting quality compared with work originating from single continents (P = .20).

LIMITATIONS

A limitation is the heterogeneity in study designs.

CONCLUSIONS

Investigations on the diagnostic utility of vessel wall MR imaging in less commonly studied intracranial vasculopathies such as dissections, aneurysms, and vasculitis are warranted. More consistent adherence to the Strengthening the Reporting of Observational Studies in Epidemiology guidelines should improve transparency and maximize effective synthesis for clinical translation. Diverse collaborative teams are encouraged to advance the understanding of intracranial vasculopathies using vessel wall MR imaging.

Detection of Stenosis Progression in Intracranial Vertebral Artery Dissection Using Carotid Ultrasonography

BACKGROUND

The purpose of this study was to assess whether carotid ultrasonography indices detect arterial stenosis progression in patients with vertebral artery (VA) dissection.

METHODS

This was a retrospective, single-center, observational study that enrolled patients with intracranial VA dissection who were admitted from January 2011 to June 2017. Magnetic resonance angiography (MRA) was done on admission and followed up at a median 20 days after onset (interquartile range [IQR] 9-58 days), and ultrasonography was performed at a median of 22 (interquartile range 7-56) days. Peak systolic velocity (PSV), end-diastolic velocity (EDV), mean velocity (MV), and pulsatility index (PI) were measured by ultrasonography, and the ratio of each follow-up value to the baseline (follow-up/baseline) value was calculated. Two stroke neurologists categorized into 3 groups by morphological changes of the dissected vessel: patients with stenosis progression (progression group: P-group); those with no remarkable change or dilatation improved (stable group: S-group); and those with stenosis regression or dilatation enlargement (enlargement group: E-group). Ultrasonography indices were compared among the groups.

RESULTS

Of the 42 patients who were enrolled to this study, 39 patients underwent ultrasonography and MRA on both admission and follow-up. The PI ratio was significantly higher in the P-group than in the S-group (1.96 ± .80 versus .98 ± .44, P = .02) and in the E-group (versus .65 ± .35, P < .01). There were no significant differences in the PSV ratio, EDV ratio, and MV ratio.

CONCLUSIONS

In patients with VA dissection, the PI ratio on ultrasonography is a promising index to detect stenosis progression.

Propensity Score-Matched Analysis of Lesion Patterns in Stroke Patients With Patent Foramen Ovale and Patients With Spontaneous Intracranial Artery Dissection

Aims: To investigate the relationship between clinical and imaging features of stroke patients with patent foramen ovale (PFO) and those with spontaneous intracranial artery dissection (SIAD).

Materials and methods: We retrospectively examined both clinical and imaging results of 40 stroke patients with PFO and 29 with SIAD. To reduce selection bias, we conducted a propensity score-matching analysis. The patients' propensity scores were estimated using a logistic regression model based on the following variables: age, sex, hypertension, diabetes mellitus, hypercholesterolemia, cigarette smoking, stroke histories, and their NIHSS scores. We compared the pattern of cerebral DWI lesions between patients with PFO and those with SIAD.

Results: After propensity score matching, 21 pairs of patients were selected. Clinical characteristics of the 2 groups were well matched. The distribution of DWI lesion patterns differed between the 2 groups. Single lesions (cortical or subcortical) were more frequently observed in the PFO group than in the SIAD group (P = 0.026). Multiple lesions in one vascular territory occurred more frequently in the SIAD group than in the PFO group (P = 0.035).

Conclusion: The present study suggests that lesion patterns observed from DWI of patients with PFO and SIAD might provide clues to the etiology of infarcts. Single lesions (cortical or subcortical) might be a typical feature of PFO associated strokes, while multiple lesions in one vascular territory might be a specific feature of SIAD associated strokes.

Intravenous thrombolysis for acute ischemic stroke: a bridge between two centuries

INTRODUCTION

Intravenous tissue-plasminogen activator (tPA) remains the only approved systemic reperfusion therapy suitable for most patients presenting timely with acute ischemic stroke. Accumulating real-word experience for over 20 years regarding tPA safety and effectiveness led to re-appraisal of original contraindications for intravenous thrombolysis (IVT). Areas covered: This narrative review focuses on fast yet appropriate selection of patients for safe administration of tPA per recently expanded indications. Novel strategies for rapid patient assessment will be discussed. The potential for mobile stroke units (MSU) that shorten onset-to-needle time and increase tPA treatment rates is addressed. The use of IVT in the era of non-vitamin K antagonist oral anticoagulants (NOACs) is highlighted. The continuing role of IVT in large vessel occlusion (LVO) patients eligible for mechanical thrombectomy (MT) is discussed with regards to 'drip and ship' vs. 'mothership' treatment paradigms. Promising studies of penumbral imaging to extend IVT beyond the 4.5-hour window and in wake-up strokes are summarized. Expert commentary: This review provides an update on the role of IVT in specific conditions originally considered tPA contraindications. Novel practice challenges including NOAC's, MSU proliferation and bridging therapy (IVT&MT) for LVO patients, and the potential extension of IVT time-window using penumbral imaging are emerging as safe and potentially effective IVT applications.

Intracranial Large Artery Disease of Non-Atherosclerotic Origin: Recent Progress and Clinical Implications

Intracranial large artery disease (ILAD) is the major cause of stroke worldwide. With the application of recently introduced diagnostic techniques, the prevalence of non-atherosclerotic ILAD is expected to increase. Herein, we reviewed recent reports and summarized progress in the diagnosis and clinical impact of differentiation between ILAD of atherosclerotic and non-atherosclerotic origin. Our review of the literature suggests that more careful consideration of non-atherosclerotic causes and the application of appropriate diagnostic techniques in patients with ILAD may not only provide better results in the treatment of patients, but it may also lead to more successful clinical trials for the treatment of intracranial atherosclerosis.

A case report of multiple cervical artery dissection after peripheral type facial palsy and use of steroids

Background

Cervical artery dissection is one of the most important causes of ischemic stroke in young age patients. However, multiple cervical artery dissection simultaneously involving the anterior and posterior circulation is uncommon. Here, we would like to report a case of a patient with bilateral vertebral artery (VA) and internal carotid artery dissection (ICA) after a use of systemic steroid due to peripheral facial palsy.

Case presentation

A 44-year-old man with hypertension visited emergency department due to recurrent vertigo. He was receiving methyl prednisolone for two weeks for the treatment of right peripheral type facial palsy which occurred after retro-orbital headache. Neurologic examination revealed severe ataxia at left side. Sensory for pain and temperature was declined in the right arm and leg. Diffusion-weighted image showed an acute ischemic lesion at the whole territory of posterior-inferior cerebellar artery. Severe stenosis was observed from bilateral VAs and ICAs on conventional magnetic resonance angiography. Intramural hematoma and intimal flap was observed from the high-resolution MRI.

Conclusions

Peripheral type facial palsy is an unusual presentation of carotid dissection. Steroids aggravate arterial dissection by increasing blood pressure and blood vessel fragility by its negative effect on connective tissue strength. Use of steroid in patients with peripheral type facial palsy with severe headache may need caution.

Extracranial vertebral artery dissection: Findings and advantages of ultrasonography

Vertebral artery dissection (VAD) is not uncommon in the young adult population. Owing to the various clinical manifestations; the diagnosis of VAD mainly depends on imaging examinations. Ultrasound has found an increasingly wide utilization in the diagnosis of VAD because of the continuous improvement in the resolution of ultrasonic instruments and accessibility.We retrospectively collected the data of patients with a US-proven extracranial vertebral artery dissection. In accordance with the sonographic findings, all patients were classified as having intramural hematoma, double-lumen dissection, and occlusion dissection. The patients' age, sex, risk factors for cerebrovascular diseases, and sonographic characteristics were analyzed.A total of 37 cases of US-proven extracranial vertebral artery dissections were included in this study. Thirty patients presented with intramural hematoma dissection, 1 had double-lumen dissection and 6 had occlusion dissection. No dissecting aneurysm was found in any of the patients. Concerning a subsequent angiographic examination, 13 patients failed to undergo the examination for various reasons. The remaining 24 patients underwent digital subtraction angiography (DSA), magnetic resonance angiography (MRA), and computerized tomographic angiography (CTA), among whom 1 patient with intramural hematoma was underdiagnosed because the DSA result was interpreted as normal. One patient who underwent CTA had a contrast allergy. In the remaining patients, the results of other imaging examinations were consistent with the US results.Intramural hematoma dissection is the most common type of extracranial vertebral artery dissection. Over other angiographic examinations US has a big diagnostic advantage for its direct view, accuracy, and low cost.

Non-traumatic vertebral artery dissection presenting with unilateral cervical pain, hemilateral vision problems and headache

Spontaneous vertebral artery dissection is a rare condition, mainly affecting young adults with non-specific symptoms, which are often considered not severe. We report a case of a non-traumatic vertebral artery dissection in a 30-year-old woman. Our patient presented with unilateral right-sided neck pain and frontal headache during 3 weeks and recently developed right-sided vision problems. History and clinical findings were non-specific. Neurovascular imaging showed a right-sided vertebral artery dissection from C2 to C6 with an intima flap at C5-C6. The patient was observed in the stroke unit for 1 week and antithrombotics were given during 3 months. There was a complete revascularization of the vertebral artery after 3 months. A review of literature is given concerning predisposing factors, clinical symptoms, neurovascular imaging and treatment options.

Headache in Intracranial and Cervical Artery Dissections

Dissection refers to a tear in the wall of an artery, with the two main types being intracranial or extracranial. Dissections tend to occur most commonly in the young, sometimes secondary to trauma involving the neck. To confirm a dissection, some type of vessel imaging is necessary, including magnetic resonance angiography (MRA), computed tomography angiography (CTA), or angiography. The most common presentation of a dissection (especially extracranial) is pain, usually head and neck pain along with a Horner's syndrome. Patients may also present with ischemic symptoms, including transient ischemic attack (TIA) or stroke, which may also be a complication of a dissection. Although headache is a common presentation, there is little research into phenotype or long-term outcomes. There are a number of case reports detailing the phenotypes of headaches that may be present in dissection, including a migraine-like or hemicrania-like headache. Dissections are usually treated with some type of anti-platelet or anti-coagulation, although there are only a few randomized controlled trials. In a new acute headache, dissection is an important diagnosis to keep in mind.

Vascular Tortuosity May Be Associated With Cervical Artery Dissection

BACKGROUND AND PURPOSE

Dissection is an increasingly recognized cause of ischemic stroke, which occurs spontaneously or after trauma, in relatively young patients. We hypothesized that there might be a predisposing factor weakening the vascular wall and that arterial tortuosity might be higher in patients with dissection.

METHODS

We consecutively enrolled cervical artery dissection (CerAD) patients who had undergone magnetic resonance angiography. Age- and sex-matched healthy subjects who underwent magnetic resonance angiography in a routine health examination were used as controls. The tortuosity was measured semiautomatically from the carotid artery and vertebral artery (VA) arteries. Tortuosity index was defined as: [(arc/chord)-1×100] in each arteries. Independent risk factors associated with CerAD were investigated using multivariable analysis. Subgroup analysis according to the dissected artery was performed.

RESULTS

There were no differences in vascular risk factors between the 75 CerAD patients and the 75 controls. The tortuosity indexes of the contralesional VA (16.3±6.8 versus 12.1±4.5, respectively; P<0.001) and carotid artery (8.8±4.0 versus 7.3±2.9, respectively; P=0.01) were higher in patients with CerAD compared with those of control subjects. VA tortuosity (odds ratio, 1.175; P=0.001) was independently associated with the presence of CerAD. In subgroup analysis, VA tortuosity was significantly higher in 57 patients with VA dissection than in controls (P<0.001), and carotid artery tortuosity was marginally higher in 18 patients with carotid artery dissection (P=0.05).

CONCLUSIONS

CerAD is associated with tortuous cervical arteries, which may implicate weakened cervical vascular structure in these patients.

Diagnosis and follow-up of posterior inferior cerebellar artery dissection complicated with ischemic stroke assisted by T1-VISTA: a report of two cases

Background

Volume isotropic turbo spin-echo acquisition (VISTA) is a new method similar to the 3D black-blood imaging method that enables visualization of a intramural hematoma. T1-VISTA has recently been applied in the diagnosis of intracranial arterial dissection. However, the identification of an intramural hematoma in posterior inferior cerebellar dissection (PICA-D) by T1-VISTA has only rarely been reported.

Case presentation

We herein report two patients who suffered from PICA-D complicated with ischemic stroke. Initial magnetic resonance arteriography was not informative, however, T1-VISTA depicted high-intensity signal areas suggesting an intramural hematoma of PICA-D in both cases. The high-intensity signal areas gradually reduced and finally disappeared at 4 months and 5 months after the onset, respectively.

Conclusion

Our cases demonstrate that T1-VISTA was able to assist in the diagnosis and follow-up of PICA-D.

Location of cerebral atherosclerosis: Why is there a difference between East and West?

Intracranial atherosclerosis is more prevalent in Asian patients, whereas extracranial atherosclerosis is more common in individuals from western countries. The reasons for this discrepancy remain unknown. We reviewed the relevant literature and discussed the currently available information. Although the study population, diagnostic modality, and risk factor definitions differ between studies, hypercholesterolemia is more correlated with extracranial atherosclerosis than intracranial atherosclerosis. The difference in hypercholesterolemia prevalence is one of the main reasons for racial differences. Intracranial arteries contain higher antioxidant level than extracranial arteries and may be more vulnerable to risk factors for antioxidant depletion (e.g., metabolic syndrome and diabetes mellitus). Intracranial arteries may be vulnerable to factors associated with hemodynamic stress (e.g., advanced, salt-retaining hypertension and arterial tortuosity) because of a smaller diameter, thinner media and adventitia, and fewer elastic medial fibers than extracranial arteries. Additionally, non-atherosclerotic arterial diseases (e.g., moyamoya disease) that commonly occur in the intracranial arteries of East Asians may contaminate the reports of intracranial atherosclerosis cases. Genes, including RNF 213 or those associated with high salt sensitivity, may also explain racial differences in atherosclerotic location. To understand racial differences, further well-designed studies on various risk and genetic factors should be performed in patients with cerebral atherosclerosis. Additionally, improvements in diagnostic accuracy via advancements in imaging technologies and increased genetic data will aid in the differentiation of atherosclerosis from non-atherosclerotic intracranial diseases.