Diagnostic usefulness of high resolution cross sectional MRI in symptomatic middle cerabral arterial dissection

Endovascular Approach in Patients with Acute Complete Occlusion Due to Middle Cerebral Artery Dissection

Objective

Dissection of the middle cerebral artery (MCA) is less common than dissection of vessels in the vertebrobasilar system or carotid artery. Acute complete occlusion related to MCA dissection is extremely rare. We report an endovascular approach in patients with acute complete occlusion due to MCA dissection.

Methods

We reviewed retrospectively the endovascular procedure and clinical results for acute-stroke patients who underwent recanalization from October 2014 through December 2018. Initial imaging findings and the endovascular procedure were analyzed for patients with acute complete occlusion due to MCA dissection.

Results

We undertook first-line aspiration thrombectomy using a Penumbra catheter in 294 patients with acute occlusion of the M1 segment. Of these patients, seven were confirmed to have acute complete occlusion due to MCA dissection. All patients had angiographic findings of an intimal flap at the proximal occlusion site of the MCA. One patient complained of severe headache during microcatheter passage through the occluded lesion and died due to massive bleeding caused by rupture of the false lumen. The remaining patients underwent initial contact aspiration thrombectomy without microcatheter passage. After aspiration thrombectomy, six patients had delayed flow through the MCA. One patient underwent stenting of the MCA because of progressive symptoms.

Conclusion

An intimal flap at the proximal portion of an occluded MCA can suggest the possibility of MCA dissection. Contrast aspiration thrombectomy without microcatheter passage can reduce the risk of false lumen rupture in cases of MCA dissection.

Superficial Temporal Artery-middle Cerebral Artery Anastomosis for Ischemic Stroke due to Dissection of the Intracranial Internal Carotid Artery with Middle Cerebral Artery Extension

A 31-year-old man presented with a sudden-onset headache, right hemiparesis, and dysarthria on day 0 and was diagnosed with acute ischemic stroke due to dissection of the left intracranial internal carotid artery with middle cerebral artery extension. His symptoms progressed despite the institution of treatment, suggesting progression of the dissection. On day 5 after symptom onset, the patient underwent superficial temporal artery-middle cerebral artery anastomosis. No new ischemic stroke event occurred after surgery. Cerebral angiography performed 6 months after surgery showed spontaneous resolution of the dissection. The patient recovered to a modified Rankin Scale score of 2 and was able to return to work. The results of the present case suggest that superficial temporal artery-middle cerebral artery anastomosis is an effective treatment for ischemic stroke due to dissection of the intracranial internal carotid artery with middle cerebral artery extension.

Post-ischaemic hyperperfusion in traumatic middle cerebral artery dissection detected by arterial spin labelling of magnetic resonance imaging

We report a patient with a traumatic middle cerebral artery dissection, which showed hyperperfusion in the territory supplied by the left middle cerebral artery. A 45-year-old man experienced speech disturbance and motor weakness in his right hemibody on the day following mild head trauma. His symptoms worsened on the fourth day. Magnetic resonance imaging showed narrowing in the left M1 portion of the middle cerebral artery. Angiography showed narrowing and dilatation in the left middle cerebral artery trunk. The lesion was diagnosed as a dissection of the middle cerebral artery. Arterial spin labelling of magnetic resonance imaging and single photon emission computed tomography showed increased cerebral blood flow in the left temporal region compared with the right. The patient was treated conservatively and the symptoms gradually improved. The hyperperfusion observed on arterial spin labelling and single photon emission computed tomography gradually improved and disappeared on the 25th day. This is the first reported case of traumatic middle cerebral artery dissection, which showed post-ischaemic hyperperfusion in the territory of the affected artery. To detect hyperperfusion in the brain, arterial spin labelling is a useful technique.

Quantitative Analysis Using High-Resolution 3T MRI in Acute Intracranial Artery Dissection

BACKGROUND AND PURPOSE

Quantitative measurements, as well as qualitative characterizations, of the vessel walls of the small intracranial arteries became clinically available and reliable beyond the resolution limit of 1.5 T high-resolution magnetic resonance imaging (HR-MRI) with the development of 3 T HR-MRI. We present the quantitative dissection findings of spontaneous and unruptured acute intracranial artery dissection (SID) using 3 T HR-MRI and investigate the differences between each cerebral artery.

METHODS

Twenty-eight lesions (anterior cerebral artery = 6; middle cerebral artery = 4; vertebral artery = 18) from 26 patients (17 male and 9 female patients; mean age = 47 years; age range = 32-74 years) with presumptive diagnoses of SID were included. The diagnosis was determined based on the clinical features, findings on luminal angiography (such as digital subtraction angiography, computed tomography, or magnetic resonance angiography), and HR-MRI. HR-MRI was performed within one month from onset. The neuroimaging indices (maximal outer diameter and area, remodeling index and modified remodeling index, and wall thickness and wall area index) of aneurysmal dilatation and the signal intensities of the intramural hematomas were rated using HR-MRI. The results were compared between each cerebral artery.

RESULTS

The maximal outer diameter and area, remodeling index and modified remodeling index, and wall thickness index and length were significantly different between anterior and posterior circulation (P < .05). The mean relative signal intensities of the intramural hematoma showed consistent values, regardless of the cerebral arteries, without significant difference.

CONCLUSIONS

Neuroimaging indices of aneurysmal dilatation may be adjunctive indicators in the evaluation of SID.

Isolated middle cerebral artery dissection: a systematic review

Acute stroke can be missed in the emergency department, particularly in younger patients and in those with more vague symptoms such as headache or dizziness. Cervicocephalic dissections are one group of etiologies for acute stroke in the young. While cervicocephalic dissections are not uncommon in clinical practice, isolated middle cerebral artery dissection (MCAD) has been rarely reported as a cause for stroke. We sought to review the clinical implications and pathophysiology of an isolated MCAD. We searched the medical literature for isolated MCAD in clinical stroke patients using MEDLINE, HighWire, and Google Scholar databases from 1966 to 2013 using the keywords 'middle cerebral artery dissection,' 'intracerebral artery dissection,' and 'middle cerebral artery dissection stroke.' We reviewed cases to learn various characteristics of isolated MCAD. A total of 61 cases (62.3% male, mean age 44.16 ± 19.17 years) were reviewed from 54 publications. Most cases were reported from Asian countries (78.7%). Ischemic strokes were more common than hemorrhagic strokes (68.9%). Digital subtraction angiography was the most common imaging modality used to diagnose isolated MCAD (75.4%). Surgery was the preferred form of therapeutic intervention (39.3%). Males (n = 27/48, p = 0.0008) and those who presented with only ischemic syndromes (n = 22/48, p = 0.0009) had significantly higher rates of favorable outcome. Isolated MCAD is a rare disease that can contribute to the stroke burden of young patients. Further studies are needed to better characterize optimal treatment strategies and define outcomes for this rare condition.

Middle cerebral artery dissection: diagnostic and prognostic value of transcranial color-coded sonography

We report 2 patients with ischemic stroke related to an initial severe focal narrowed middle cerebral artery caused by a dissection mechanism, a presentation that has received little attention to date. Diagnostic modalities and follow-up using transcranial color-coded sonography are reported and discussed. Results with transcranial color-coded sonography were correlated with computed tomographic angiography, showing the great value of this radiation-free arterial monitoring process in this setting, especially in young adults.

Imaging investigation of intracranial arterial dissecting aneurysms by using 3 T high-resolution MRI and DSA: from the interventional neuroradiologists' view

OBJECTIVES

The purpose of this study was to investigate vessel wall imaging features combined with the luminal shapes of intracranial dissecting aneurysms (IDAs) by using 3 Tesla (3T) high-resolution magnetic resonance imaging (MRI) and digital subtraction angiography (DSA).

METHODS

Sixty-seven patients with 76 IDAs were consecutively enrolled in the study from December 2011 to May 2013. DSA was performed to diagnose an IDA and to categorize its angiography patterns into either aneurysmal dilation, steno-occlusive, combined, or unclassifiable. Images of 3T high-resolution MRI were used to evaluate arterial wall imaging features of each lesion. Chi-squared tests were used for statistical analyses.

RESULTS

Aneurysmal dilation (51 of 76, [67%]) was the most common angiography pattern of IDAs, followed by the combined pattern (20 of 76, [26%]). Seven percent (five of 76) of IDAs showed steno-occlusive (n = 3) and unclassifiable (n = 2) angiography patterns, in which intramural hematomas were detected in the arterial wall without luminal connection. Intimal flaps (32 of 76, [42%]), double-lumen sign (38 of 76, [50%]) and intramural hematomas (46 of 76, [61%]) were recognized as the characteristic features of dissection by high-resolution MRI. Intramural hematomas occurred more frequently in the combined patterns group (16 of 20, [80 %]) than in the aneurysmal dilation group (25 of 51, [49%]) (P = .017), while the occurrence of intimal flaps and double-lumen sign did not differ between angiographic patterns (P > .05).

CONCLUSIONS

3T high-resolution MRI combined with DSA offered clear visualization of vessel wall features and accurate assessment of the vessel lumen in IDAs. This combined approach would be highly useful for understanding the underlying pathological status of IDAs and in guiding treatment choices.