Duplex Scanning Diagnosis of Internal Carotid Artery Dissections

Breakthrough of dual-phase CT angiography features of carotid web and its correlation with ischemic stroke

PURPOSE

To investigate the diagnostic value of dual phase CT angiography (CTA) in carotid web and its correlation with ischemic stroke.

METHODS

The imaging data of 726 patients with cervical CTA from January 2015 to November 2019 in Taizhou People's hospital were retrospectively and consecutively analyzed. A total of 16 patients with 23 carotid webs were obtained. The location, morphology and clinical data of 16 patients were observed. Carotid web was identified by two experienced radioimaging experts according to the characteristics of a thin intraluminal filling defect along the posterior wall of the carotid bulb on sagittal CTA and a septum structure in arteries on axial CTA.

RESULTS

In the arterial phase, 23 carotid webs in 16 patients showed membrane like separation in the lumen of the posterior wall of the carotid bulb, and one web extended into the internal and external carotid arteries in a "Y" shape. There were 9 males and 7 females. In venous phase, 16 carotid webs showed linear enhancement, and 15 sites showed delayed emptying of contrast medium at the lateral margin. Five patients were acute or chronic ischemic stroke. The kappa coefficient for interobserver agreement in diagnosing carotid web was 0.79.

CONCLUSION

Dual-phase CTA is effective and reliable method to identifying carotid webs, which may be associated with ischemic stroke.

Imaging and clinical features of cervical artery web: report of 41 cases and literature review

This study investigated the imaging and clinical features of cervical artery web to improve disease diagnosis. Imaging and clinical data of 41 patients with cervical artery web were retrospectively analyzed and summarized in the context of the literature. Of the 8653 patients who underwent carotid computed tomography angiography (CTA) in the past 3 years at our hospital, 41 (0.47%) were diagnosed with cervical artery web. Among the 41 patients, there were 38 web structures in typical position, including 26 web structures located in the internal carotid artery and 12 in the proximal bifurcation of the common carotid artery. And the other three web structures were located outside carotid artery, including two in the subclavian artery and one in the vertebral artery. There were 47 web structures in 41 cases of cervical artery web; 35/41 (85.3%) were unilateral and 6/41 (14.7%) were bilateral. Among 41 patients, there were 20 patients who had cerebral infarction, 14 who experienced transient ischemic attack, 3 patients with cerebral hemorrhage; and 4 with other manifestations. Cervical artery web showed typical imaging features in the carotid CTA. Cervical artery web was most common in the internal carotid artery and at the bifurcation of the common carotid artery. It was also occasionally found in other rare artery such as vertebral and subclavian artery. Based on the various locations of web structure, we think it is necessary to rename carotid web as cervical artery web. Most of the attachment sites of the web structures were located in the posterior wall of the lumen, followed by the lateral wall; sites on the anterior wall were rare. Cervical artery web may be an underappreciated risk factor for stroke. And hypertension can increase the incidence of ischemic stroke in patients with cervical artery web.

Spontaneous cervical artery dissection in patients aged over 70 years: two cases and systematic literature review

OBJECTIVE

Spontaneous cervical artery dissection (CAD) is a cerebrovascular disease typically considered to affect the young population. Literature reports cases in the elderly only as incidental findings, making the diagnosis unlikely in older patients. Incidence and pathogeny in this specific population remain to be assessed.

METHODS

We reviewed patients aged over 70 years admitted for spontaneous CAD in the Stroke Unit of the University Hospital of Nancy (northeastern France) over a period of 12 years as well as all reported cases in literature.

RESULTS

During this period, only two patients aged over 70 years were diagnosed with internal carotid artery dissection in our center. The first patient was diagnosed with the typical radiological feature of long tapered stenosis due to mural hematoma. The second patient presented with the classic painful Horner syndrome. Literature review identified only two case reports and eight studies with an age range above 70 years. Headache was present in nearly all documented cases. Radiological features were the same as those usually described in younger patients.

CONCLUSIONS

Even if spontaneous CAD in patients aged over 70 years would appear to be rare, it does occur with comparable clinical and radiological features as in the younger population. CAD is probably underdiagnosed in this population due to a higher prevalence of more common causes of stroke at this age. However, a simple investigation into headache or the Horner syndrome during the patient's diagnostic workup would lead to adapted exploration of cervical arteries and improve detection of CAD in the elderly.

Combined linear array high- and convex array low-frequency duplex ultrasonography with or without examination of the ophthalmic artery in the differential diagnosis of occlusion from severe stenosis of internal carotid artery

PURPOSE

To assess the benefits of using a low-frequency convex probe and detecting ophthalmic artery blood flow for the differential diagnosis of occlusion from severe stenosis of the internal carotid artery (ICA).

METHODS

A total of 103 patients were enrolled and had three sequential examinations by an experienced sonographer. First, the proximal ICA was examined with a 5.0-7.5-MHz linear probe. Second, the distal ICA was examined with a 3.5-5.0-MHz convex probe. Third, the ophthalmic artery (OA) was examined with a 5.0-7.5-MHz linear probe. Three parallel sets of diagnoses were made based on results from (1) high-frequency ultrasonography; (2) combined use of high- and low-frequency ultrasonography; and (3) combined use of high- and low-frequency ultrasonography along with OAs examination findings. Efficiencies of the three diagnoses were compared by receiver operating characteristic curves with digital subtraction angiography as the gold standard.

RESULTS

The second diagnostic approach yielded the highest sensitivity (96.6%) and specificity (94.5%). OA blood flow was reversed in most, but not all, cases of ICA occlusion (27/29). Areas under the receiver operating characteristic curves of the three diagnoses were significantly different (p < 0.05).

CONCLUSIONS

The diagnostic performance of combined high- and low-frequency ultrasonography is greater than that of high-frequency ultrasonography alone. Although OA examination does not increase the diagnostic performance, it provides helpful data for the assessment of hemodynamics and collateral circulation.

[Traumatic dissection of the internal carotid artery following whiplash injury. Diagnostic workup and therapy of an often overlooked but potentially dangerous additional vascular lesion]

We report on the case of a 33-year-old male patient who was brought to the emergency room of our hospital after suffering a high-energy trauma due to an automobile accident. Besides a scaphoid fracture there were no signs of any neurological deficits. After several hours without clinical symptoms the patient developed dysarthria as the first manifestation of local cerebral ischemia based on a traumatic dissection of the internal carotid artery. Under systemic high-dose heparin therapy, fast and complete remission of all neurological disorders could be achieved. In the course of time a dissecting aneurysm developed. Temporary anticoagulation with phenprocoumon was started in the meantime and no further complications have appeared up to now. Besides presenting this absorbing case, this article highlights the diagnostic and therapeutic regime in cases of a traumatic dissection of supra-aortal arteries for rapid and adequate management of this rare but potentially dangerous complication.

A novel treatment for embolising carotid dissection

INTRODUCTION

A rare but significant cause for stroke is sub-intimal carotid dissection and this mechanism accounts for approximately 2.5% of all strokes.(1) Dissection of the carotid artery is often caused by trauma to the face or neck.(2) Under 45 years old, it is the second leading cause of stroke.(3) Neurological symptoms can be lacking or subtle, therefore the condition may be overlooked but the pathological processed is believed to be attributed to thromboembolism.(4) Microemboli in the middle cerebral artery, are known as a risk factor for ischaemic stroke following a transient ischaemic attack (TIA) and can be detected by transcranial Doppler examination (TCD).(5) The established treatment regime is antiplatelet therapy, anticoagulation or both along with supportive therapy.(6) Current evidence suggests managing microemboli in both crescendo TIA's and post carotid endarterectomy improves outcome.(7) We have found the use of Tirofiban, a potent intravenous antiplatelet agent currently licensed for use in acute coronary syndrome, effective in the treatment of microemboli in this manner.(7)

CASE PRESENTATION

We report a case of symptomatic carotid artery dissection post radical neck dissection, causing TCD detected microemboli and successfully treated with Tirofiban.

CONCLUSION

We believe further study into the use of Tirofiban in the treatment of microemboli after carotid dissection is indicated.

Cerebrovascular Dissections—A Review Part I: Spontaneous Dissections

Spontaneous cerebrovascular dissections are subintimal or subadventitial cervical carotid and vertebral artery wall injuries and are the cause of as many as 2% of all ischemic strokes. Spontaneous dissections are the leading cause of stroke in patients younger than 45 years of age, accounting for almost one fourth of strokes in this population. A history of some degree of trivial trauma is present in nearly one fourth of cases. Subsequent mortality or neurological morbidity is usually the result of distal ischemia produced by emboli released from the injury site, although local mass effect produced by arterial dilation or aneurysm formation also can occur. The gold standard for diagnosis remains digital subtraction angiography. Computed tomography angiography, magnetic resonance angiography, and ultrasonography are complementary means o evaluation, particularly for injury screening or treatment follow-up. The annual rate of stroke after injury is approximately 1% or less per year. The currently accepted method of therapy remains antithrombotic medication, either in the form of anticoagulation or antiplatelet agents; however, no class I medical evidence exists to guide therapy. Other options for treatment include thrombolysis and endovascular therapy, although the efficacy and indications for these methods remain unclear.

Imaging of traumatic arterial injuries in the neck with an emphasis on CTA

Arterial injuries in the neck may be secondary to blunt or penetrating trauma. Because of clinical difficulties in early identification of these injuries as well as their potentially catastrophic consequences, imaging is indispensible in the diagnosis of arterial injuries in the neck. Computed tomography angiography (CTA) has become the initial study of choice in management of these patients. We review the clinical and imaging features of vascular injuries of the neck with special emphasis on CTA.

Bilateral carotid artery dissection after high impact road traffic accident

A 58 year old man was involved in a high impact road traffic incident and was admitted for observation. Asymptomatic for the first 24 hours, he collapsed with symptoms and signs consistent with a cerebrovascular accident. Computed tomography angiogram (CTA) and Magnetic resonance angiogram (MRA) demonstrated bilateral internal carotid artery dissections and a left middle cerebral artery infarct. It was not considered appropriate to attempt stenting or other revascularistation. The patient was treated with heparin prior to starting warfarin. He made a partial recovery and was discharged to a rehabilitation facility. This case is a reminder of carotid dissection as an uncommon but serious complication of high speed motor vehicle accident, which may be silent initially. Literature Review suggests risk stratification before relevant radiological screening at risk patients. Significant advances in CTA have made it the diagnostic tool of choice, but ultrasound is an important screening tool.