MRI- and MRA-guided therapy of carotid and vertebral artery dissections

Traumatic extracranial internal carotid-jugular fistula leading to serious injury: a case report in forensic assessment

Extracranial carotid artery injuries may produce severe haemorrhage, cerebral damage or arteriovenous fistula. Examples of traumatic extracranial carotid-jugular fistula are not frequently reported, especially in forensic medicine. We report a controversial case of an extracranial internal carotid-jugular fistula resulting from a stab wound to the neck. The degree of the injury was classified under "The Standard of Human Body Injury Assessment (2014)" (SIA) in China by forensic examiners. We believe this case report will provide information for the forensic assessment of similar cases.

Ultrasound Diagnosis of Spontaneous Carotid Dissection With Isolated Horner Syndrome

Background and Purpose— Isolated Horner syndrome without associated cranial nerve palsies or ischemic symptoms is an important presentation of spontaneous internal carotid artery dissection (sICAD). Ultrasound is often used as a screening method in these patients because cervical MRI is not always available on an emergency basis. Current knowledge on ultrasound findings in patients with sICAD presenting with isolated Horner syndrome is limited.

Methods— Patients were recruited from prospective cervical artery dissection databases of 3 tertiary care centers. Diagnosis of sICAD was confirmed by cervical MRI and MR angiography or digital subtraction angiography in all patients. Data on Doppler sonography and color duplex sonography examinations performed within 30 days of symptom onset were analyzed.

Results— We identified 88 patients with Horner syndrome as the only sign of sICAD. Initial ultrasound examination was performed in 72 patients after a mean time interval from symptom onset to examination of 11 (SD 8) days. The overall frequency of false-negative ultrasound findings was 31% (22 of 72 patients). It showed stenosis ≥80% or occlusion in 34 (47%) patients, and stenosis ≤80% in 16 (22%). It visualized mural hematoma in 7 patients and intimal flap in one. Patients with normal ultrasound were less frequently smokers (9% versus 28%, P =0.034), and had less frequently migraine without aura (9% versus 43%, P =0.012) or neck pain (18% versus 62%, P =0.003) than those with pathological ultrasound findings.

Conclusions— Nearly one third of patients with Horner syndrome as the only sign of sICAD presented with normal ultrasound findings. These results indicate that ultrasound is not a reliable method to diagnose sICAD in patients with isolated Horner syndrome.

[Clinical treatment and therapy for dissected cervicocerebral artery]

Dissection of a cervicocerebral artery (CAD) is the second leading cause of stroke at younger ages. The pathogenesis of spontaneous CAD is not fully clarified. Defective connective tissue components may cause an arteriopathy predisposing to CAD in combination with certain trigger and risk factors. The clinical spectrum includes local pain in the neck, headaches, Horner's syndrome, isolated cranial nerve deficits, and hemispheric or brainstem infarction. Noninvasively, CAD is confirmed by Duplex sonography, MRI, and MRA. There is no controlled study for best treatment or management. Rational initial empiric treatment in acute CAD to prevent secondary embolism is partial thromboplastin time-guided anticoagulation by intravenous heparin followed by anticoagulation with warfarin. Carotid surgery for treating CAD is not recommended. The duration of anticoagulation is best guided by Doppler sonography follow-up and should extend until normalization of blood flow or at least 6 months after the vessel was occluded. Caution should be recommended for exercises that involve excessive head movements. The recurrence rate for CAD is low at <1%/year except for patients with known hereditary connective tissue disorders or in cases with familial dissections.

Duplex Scanning Diagnosis of Internal Carotid Artery Dissections

BACKGROUND

The reliability of duplex scanning (DS) for the diagnosis of internal carotid artery dissections (ICAD) is not clear.

METHODS

Nine DS signs known to be suggestive for the diagnosis of ICAD were compared between 70 patients with ICAD and 70 matched patients without dissection.

RESULTS

Visible internal tapering occlusion, regular eccentric narrowing channel, ectasia beyond the carotid bulb, resistive index asymmetry, blood flow slowdown, ophthalmic artery blood flow inversion, and biphasic flow are more frequent in cases than in controls (p < 0.001). Atheroma plaques were absent in 80% of ICAD. When DS direct signs and hemodynamic signs were studied, sensitivity was 90% and specificity 60%.

CONCLUSION

Diagnosis of ICAD by DS could be improved if direct signs were combined with hemodynamic signs, giving a high sensitivity and a rather good specificity.

Guidelines for Prevention of Stroke in Patients With Ischemic Stroke or Transient Ischemic Attack

The aim of this new statement is to provide comprehensive and timely evidence-based recommendations on the prevention of ischemic stroke among survivors of ischemic stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches for atherosclerotic disease, antithrombotic treatments for cardioembolism, and the use of antiplatelet agents for noncardioembolic stroke. Further recommendations are provided for the prevention of recurrent stroke in a variety of other specific circumstances, including arterial dissections; patent foramen ovale; hyperhomocysteinemia; hypercoagulable states; sickle cell disease; cerebral venous sinus thrombosis; stroke among women, particularly with regard to pregnancy and the use of postmenopausal hormones; the use of anticoagulation after cerebral hemorrhage; and special approaches for the implementation of guidelines and their use in high-risk populations.

Accuracy of Color Duplex Ultrasound Diagnosis of Spontaneous Carotid Dissection Causing Ischemia

Background and Purpose— Spontaneous dissection of the cervical internal carotid artery (sICAD) is mainly assessed with MRI and magnetic resonance angiography (MRA), which are not always at hand. In contrast, color duplex sonography (CDS) is readily available. We undertook this prospective study to examine the accuracy of CDS to diagnose sICAD in patients with first carotid territory ischemia.

Methods— Consecutive patients with first carotid territory stroke or transient ischemic attack or retinal ischemia underwent clinical and laboratory examinations, ECG, CDS of the cerebral arteries, cranial computed tomography in case of stroke or transient ischemic attack, and echocardiography and 24-hour ECG in selected cases. Patients were included, if they were <65 years of age, CDS showed a probable sICAD (cervical internal carotid artery stenosed or occluded), or had no determined etiology of ischemia. All of the included patients underwent cervical MRI and MRA±cerebral catheter angiography. The sonographer was blinded to the results of MRI and angiography studies.

Results— We included 177 of 1652 screened patients. Excluded patients (n=1475) were ≥65 years old (n=818), had another determined cause of ischemia (n=1475), and had intracranial hemorrhage (n=58). CDS diagnosed sICAD in 77 of 177 patients, and the etiology of ischemia was undetermined in the remaining 100 patients. Cervical MRI and angiography showed 74 sICAD; there were 6 falsely positive and 3 falsely negative CDS findings. Thus, sensitivity, specificity, and positive and negative predictive values for CDS diagnosis of patients with sICAD causing carotid territory ischemia was 96%, 94%, 92%, and 97%, respectively.

Conclusions— Color duplex ultrasound allows the reliable exclusion of sICAD in patients with carotid territory ischemia, whereas diagnosis of CDS of sICAD must be confirmed with cervical MRI and MRA.

Cervical Artery Dissection. A Comparison of Highly Dynamic Mechanisms: Manipulation versus Motor Vehicle Collision

OBJECTIVE

To examine the similarities and dissimilarities between cervical chiropractic manipulative therapy and whiplash, and their respective relation to cervical artery dissection.

DATA SOURCES

A literature synthesis used MEDLINE-PubMed and MANTIS literature searches. A total list of 99 relevant articles was generated. Additional references were collected from citations incorporated within the included articles.

RESULTS

Both neck manipulation and motor vehicle collision events apply loads to the spinal column rapidly. While neck manipulation loads are slower to develop and displacements smaller, they may reach peak amplitudes on maximum effort comparable to those seen in low-velocity collision experiments. In contrast to reports that the vertebral artery experiences elongations exceeding its physiological range by up to 9.0 mm during simulated whiplash, strains incurred during cervical manipulative therapy have been reported to be approximately one ninth of those required for mechanical failure, comparable to forces encountered in the course of diagnostic range of motion examination. Additionally, long-lasting abnormalities of blood flow velocity within the vertebral artery have been reported in patients following common whiplash injuries, whereas no significant changes in vertebral artery peak flow velocity were observed following cervical chiropractic manipulative therapy.

CONCLUSIONS

Perceived causation of reported cases of cervical artery dissection is more frequently attributed to chiropractic manipulative therapy procedures than to motor vehicle collision related injuries, even though the comparative biomechanical evidence makes such causation unlikely. The direct evidence suggests that the healthy vertebral artery is not at risk from properly performed chiropractic manipulative procedures.

Association of internal carotid artery dissection and chiropractic manipulation

BACKGROUND

To determine the relationship between chiropractic manipulative therapy and internal carotid artery dissection, a MEDLINE literature search was performed for the years 1966 through 2000 using the terms internal carotid dissection. Literature that included information concerning causation of ICAD, as well as all case studies and series, was selected for review.

REVIEW SUMMARY

In reviewing the cases of internal carotid dissection potentially related to CMT, there were many confounding factors, such as connective tissue aberrations, underlying arteriopathy, or coexistent infection, that obscured any obvious cause-and-effect relationship. To date there are only 13 reported cases of ICAD temporally related to CMT. Most ICADs seem to occur spontaneously and progress from local symptoms of headache and neck pain to cortical ischemic signs. Approximately one third of the reported cases were manipulated by practitioners other than chiropractic physicians, and because of the differential risk related to major differences in training and practice between practitioners who manipulate the spine, it would be inappropriate to compare adverse outcomes between practitioner groups.

CONCLUSIONS

The medical literature does not support a clear causal relationship between CMT and ICAD. Reported cases are exceedingly scarce, and none support clear cause and effect.

Uneventful upper cervical manipulation in the presence of a damaged vertebral artery

OBJECTIVE

To discuss a case in which a patient with a previously injured vertebral artery underwent manipulation in the upper cervical spine without alteration of her symptom pattern. The literature concerning the relative safety of specific upper cervical manipulative techniques is reviewed.

CLINICAL FEATURES

A 42-year-old woman had a 3-week history of unilateral suboccipital pain that she related to a sudden twisting of her head and neck that occurred while she was putting sheets of drywall on top of her car. Subsequent examination by a neurologist 2 weeks later was unremarkable, and a tension-type headache was diagnosed. Approximately 10 days later (3 weeks after injury), a single high-velocity upper-cervical manipulation (incorporating slight rotation and full lateral flexion) was performed with no change in her symptom pattern. Two weeks after that, the patient had development of a lateral medullary syndrome (also known as Wallenberg syndrome) after she briefly extended and rotated her upper cervical spine while painting a ceiling.

INTERVENTION AND OUTCOME

The patient was treated with anticoagulant therapy, and the lateral medullary infarct healed without incident. The spinocerebellar and subtle motor symptoms also resolved, but the ipsilateral suboccipital headache and the loss of temperature sensation associated with the spinothalamic tract lesion were still present 9 months later.

CONCLUSION

This case report demonstrates that vigorous manipulation of the upper cervical spine is possible without injuring an already damaged vertebral artery. It is suggested that the line of drive used during the single manipulation, almost pure lateral flexion with slight rotation, was responsible for the apparent innocuous response. Guidelines for the evaluation and management of vertebral artery dissection are reviewed. Because it is currently impossible to identify patients at risk of having a dissected vertebral artery with standard in-office examination procedures, rotational manipulation of the upper cervical spine should be abandoned by all practitioners, and schools should remove such techniques from their curriculums.

Mr angiography in cerebrovascular disease

MR angiography has become a realistic diagnostic option for patients with neurovascular disease. MR angiography is not a single imaging sequence, but a collection of related methods for obtaining angiographic data. As a guide for practice, we review the literature on MR angiography in a spectrum of neurovascular indications with particular attention paid to choice of technique. The principles underlying the different techniques available are also presented. Summers, P. E.et al.

Bilateral spontaneous dissection of the internal carotid arteries--a case report

A 41-year-old African American man presented with an acute stroke secondary to bilateral spontaneous internal carotid artery dissections following exercise. Spontaneous bilateral carotid artery dissection is an unusual and uncommon occurrence that can be successfully diagnosed by color-flow duplex ultrasonography and magnetic resonance imaging/magnetic resonance angiography (MRI/MRA) imaging. A review of the literature and the authors' experience supports initial medical management of these patients. Surgery should be considered for those patients who exhibit progressive neurologic symptoms during medical management or when significant carotid artery complications, aneurysms, or flow-limiting stenoses persist.

MR angiography for the long-term follow-up of dissecting aneurysms of the extracranial internal carotid artery

OBJECTIVE

We used MR angiography to examine and follow up the changes of dissecting aneurysms of the extracranial internal carotid artery (ICA).

MATERIALS AND METHODS

We retrospectively reviewed the records of 101 consecutive patients with dissecting aneurysms of the extracranial ICA. Twenty patients with 26 spontaneous dissecting aneurysms were followed up with MR angiography every 1-2 years (men, 16; women, four; age range, 28-67 years; mean age, 51 years).

RESULTS

The mean duration of follow-up was 41 months (range, 10-93 months). At MR angiography follow-up, 20 aneurysms did not change, four decreased from their original size by 33-53% (mean, 43%), and two resolved. One patient had an asymptomatic recurrent dissecting aneurysm of the extracranial ICA. Clinically, no patient had a thromboembolic stroke or transient ischemic attack during the follow-up period.

CONCLUSION

MR angiography revealed that dissecting aneurysms of the extracranial ICA remain stable, decrease in size, or resolve--but they do not increase in size.