Mechanical thrombectomy for acute ischemic stroke with occlusion of the M2 segment of the middle cerebral artery: A literature review

Mechanical thrombectomy for middle cerebral artery M2 occlusions

BACKGROUND

The safety and efficacy of mechanical thrombectomy (MT) for proximal large vessel occlusion after acute ischemic stroke (AIS) have been demonstrated. Clinical investigations of endovascular approaches for treating AIS due to M2 occlusions have been ongoing.

PURPOSE

To assess the outcomes of M2 occlusions according to treatment modality and anatomical division.

METHODS

A total of 113 consecutive M2 occlusions treated with endovascular treatment (EVT) at our tertiary stroke center between January 2019 and December 2022 were retrospectively analyzed. Patients were divided into three groups: mechanical thrombectomy (MT); intravenous thrombolysis plus MT (IVT + MT); and IVT alone. The primary outcomes were good prognosis (mRS = 0-2) and mortality (mRS = 6) on day 90. The secondary outcome was to determine the differences in outcomes between lesions in the superior and inferior branches of M2.

RESULTS

In total, 55 (48.7%) patients underwent MT. In 42 (37.2%) patients, bridging IVT was performed with MT, and IVT alone was applied in 16 (14.2%) patients. Neither the prognosis at 90 days nor the mortality rate significantly differed among the groups. The outcomes did not significantly differ between occlusions in the superior and inferior branches of M2.

CONCLUSION

MT was found to be safe and effective for treating M2 occlusions in this series.

Anatomical distribution and clinical significance of middle cerebral artery M2 segment vessel occlusions and its cortical branches in acute ischaemic stroke patients

Background

Characterisation of anatomical distribution and the clinical impact of middle cerebral artery M2 (MCA-M2) segment occlusion and its subsequent cortical branches (CBs) in acute ischaemic stroke patients (AIS).

Methods

Retrospective, monocentric study analysing radiological and clinical data of AIS patients with MCA-M2 segment occlusion with regard to the anatomic distribution of MCA-M2 occlusion and its subsequent CB.

Results

A total of 203 patients (median age 77 (IQR 66-83) years, 112 women) were included. There was an equal distribution of right-sided versus left-sided MCA-M2 vessel occlusions (right: n=97; left: n=106), as well as with a median number of affected MCA-M2 CBs of 4 (IQR, 3-6) and a median National Institute of Health Stroke Scale score (NIHSS) on admission of 9 (3-15). For both hemispheres, CBs of the inferior trunks were significantly more affected than the superior trunks. Endovascular treatment (EVT, n=94) was associated with a significant better outcome compared with patients with medical management alone (p=0.027).

Conclusion

In acute MCA-M2 segment occlusions, inferior trunks are significantly more affected compared with the superior trunks. The subsequent CBs of the paracentral region of both hemispheres are more commonly involved. In eloquent vascular territories, EVT was more often performed.

Automated detection of intracranial large vessel occlusions using Viz.ai software: Experience in a large, integrated stroke network

BACKGROUND AND PURPOSE

Endovascular thrombectomy is an evidence-based treatment for large vessel occlusion (LVO) stroke. Commercially available artificial intelligence has been designed to detect the presence of an LVO on computed tomography angiogram (CTA). We compared Viz.ai-LVO (San Francisco, CA, USA) to CTA interpretation by board-certified neuroradiologists (NRs) in a large, integrated stroke network.

METHODS

From January 2021 to December 2021, we compared Viz.ai detection of an internal carotid artery (ICA) or middle cerebral artery first segment (MCA-M1) occlusion to the gold standard of CTA interpretation by board-certified NRs for all code stroke CTAs. On a monthly basis, sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Trend analyses were conducted to evaluate for any improvement of LVO detection by the software over time.

RESULTS

3851 patients met study inclusion criteria, of whom 220 (5.7%) had an ICA or MCA-M1 occlusion per NR. Sensitivity and specificity were 78.2% (95% CI 72%-83%) and 97% (95% CI 96%-98%), respectively. PPV was 61% (95% CI 55%-67%), NPV 99% (95% CI 98%-99%), and accuracy was 95.9% (95% CI 95.3%-96.5%). Neither specificity or sensitivity improved over time in the trend analysis.

CONCLUSIONS

Viz.ai-LVO has high specificity and moderately high sensitivity to detect an ICA or proximal MCA occlusion. The software has the potential to streamline code stroke workflows and may be particularly impactful when emergency access to NRs or vascular neurologists is limited.

Endovascular therapy for cerebral infarction due to Trousseau syndrome in a patient with non-small cell lung cancer

We describe a case of Trousseau's syndrome in a patient with lung carcinoma. A 69-year-old man presented with pleural effusion. Further evaluation revealed EGFR mutation-positive non-small cell carcinoma in the upper lobe with extensive lymph node, bone, and brain metastases. Administration of osimertinib, an EGFR tyrosine kinase inhibitor, resulted in partial tumor response, but caused osimertinib-induced pneumonitis 10 weeks later. Prednisolone restrained lung injury progression and was gradually tapered. However, he presented with impaired consciousness and right hemiplegia. Magnetic resonance imaging revealed a left middle cerebral artery M1 segment occlusion. D-dimer level was elevated to 19.5 μg/mL. In the absence of atherosclerotic or cardiogenic thrombi, these findings led to the diagnosis of Trousseau syndrome. Endovascular therapy, but not tissue plasminogen activator, improved his condition with no recurrences. These treatment strategies are crucial to restore function in patients with potentially disabling cerebral infarction due to Trousseau syndrome.

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Systemic anticoagulation for Trousseau syndrome generally has a poor prognosis.

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There is no established treatment for cancer-associated cerebral infarction.

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We performed endovascular therapy for cerebral infraction due to Trousseau syndrome.

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Endovascular therapy was effective for recanalization of the occluded artery.

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An NIHSS score of 0 was achieved with no recurrence.

Nanomedicines, an emerging therapeutic regimen for treatment of ischemic cerebral stroke: A review

Owing to its intricate pathophysiology, cerebral stroke is a serious medical condition caused by interruption or obstruction of blood supply (blockage of vasculature) to the brain tissues which results in diminished supply of essential nutrients and oxygen (hypoxia) and ultimate necrosis of neuronal tissues. A prompt risks assessment and immediate rational therapeutic plan with proficient neuroprotection play critically important role in the effective management of this neuronal emergency. Various conventional medications are being used for treatment of acute ischemic cerebral stroke but fibrinolytic agents, alone or in combination with other agents are considered the mainstay. These clot-busting agents effectively restore blood supply (reperfusion) to ischemic regions of the brain; however, their clinical significance is hampered due to various factors such as short plasma half-life, limited distribution to brain tissues due to the presence of highly efficient physiological barrier, blood brain barrier (BBB), and lacking of target-specific delivery to the ischemic brain regions. To alleviate these issues, various types of nanomedicines such as polymeric nanoparticles (NPs), liposomes, nanoemulsion, micelles and dendrimers have been designed and evaluated. The implication of these newer therapies (nanomedicines) have revolutionized the therapeutic outcomes by improving the plasma half-life, permeation across BBB, efficient distribution to ischemic cerebral tissues and neuroprotection. Furthermore, the adaptation of some diverse techniques including PEGylation, tethering of targeting ligands on the surfaces of nanomedicines, and pH responsive features have also been pondered. The implication of these emerging adaptations have shown remarkable potential in maximizing the targeting efficiency of drugs to ischemic brain tissues, simultaneous delivery of drugs and imaging agents (for early prognosis as well as monitoring of therapy), and therapeutic outcomes such as long-term neuroprotection.