A Case of Acute Embolism of the Accessory Middle Cerebral Artery Treated Using ADAPT Thrombectomy without Lesion Passing.

An accessory middle cerebral artery (AMCA) is a variant vessel that branches from the anterior cerebral artery (ACA) and runs through the Sylvian fissure along the middle cerebral artery (MCA). We report a case of acute embolic occlusion of the AMCA that was treated with thrombectomy using direct aspiration first pass technique (ADAPT). An 88-year-old woman with a history of atrial fibrillation, loss of consciousness, and right hemiparesis was referred to our hospital. Diffusion-weighted magnetic resonance imaging (MRI) showed high signal intensity in the left frontal lobe, insular cortex, and deep white matter, and magnetic resonance angiography (MRA) demonstrated left internal carotid artery (ICA) occlusion. Mechanical thrombectomy using the ADAPT technique was performed with complete recanalization. Final angiography revealed left ACA and AMCA because of the thrombus located at the origin of the left ACA and AMCA. In the case of an acute ischemic stroke associated with AMCA, it is difficult to understand and recognize the anatomy of the vessel before thrombectomy. Therefore, the ADAPT technique, which can treat acute embolic occlusion without lesion passing, is recommended due to its safety. If there is a mismatch between the perfusion area of the occluded artery and the ischemic area or the neurological findings before thrombectomy, it is extremely important to keep in mind the presence of vessel variation in the MCA.

Cortical and Internal Watershed Infarcts Might Be Key Signs for Predicting Neurological Deterioration in Patients with Internal Carotid Artery Occlusion with Mild Symptoms.

BACKGROUND: Treatment for acute ischemic stroke due to large vessel occlusion (LVO) with mild symptoms is under discussion. Although most patients have good outcomes, some patients deteriorate and have unfavorable results. Imaging findings that predict the prognosis of LVO with mild symptoms are needed to identify patients who require treatment. In this study, we focused on watershed infarctions (WSIs), because this clinical phenomenon quite sensitively reflects changes in cerebral blood flow. The purpose of this study was to assess positive rates of WSI on MRI findings in patients with internal carotid artery (ICA) occlusion, and compare WSI-positive rates between patients divided according to their clinical course. METHODS: We retrospectively collected data of 1,531 patients who presented with acute ischemic stroke between June 2006 and July 2019. Among them, we chose symptomatic ICA occlusion patients with a past history of atrial fibrillation who were treated conservatively. We divided these patients into two groups, those with maintenance or improvement in their NIHSS score after hospitalization, and those whose NIHSS score worsened. We compared WSI-positive rates between these two groups. RESULTS: Thirty-seven of the 1,531 patients were included in this study. Of them, total NIHSS score was maintained or improved in 8 patients (group A), 3 of whom (37.5%) had internal watershed infarctions (IWIs). In group B, consisting of patients whose NIHSS score worsened by >2 at 7 days from symptom onset, 24 (82.8%) had IWIs. Group A thus had statistically lower IWI positivity rates than group B (p = 0.02). Three patients (37.5%) in group A had cortical watershed infarctions (CWIs), while 27 patients in group B (93.1%) had CWIs. Group A thus had a significantly lower CWI positivity rate than group B (p = 0.002). CONCLUSION: In patients with mildly symptomatic ICA occlusion, CWIs and IWIs might be key signs for predicting neurological deterioration after hospitalization.

Nicotine does not affect stem cell properties requisite for suicide gene therapy against glioma.

OBJECTIVE:: Glioblastoma is one of the most lethal tumors in adult central nervous system with a median survival of a year and half and effective therapeutic strategy is urgently needed. For that reason, stem cell-based suicide gene therapies have attracted much interest because of potent tumor tropism of stem cells and bystander effect. In this current clinical situation, stem cells are promising delivery tool of suicide genes for glioma therapy. Since habitual cigarette smoking still prevails worldwide, we investigated the effect of nicotine on stem cell tropism toward glioma and gap junctional intercellular communication (GJIC) function between glioma and stem cells, both of which are important for suicide gene therapies. Methods: Mouse induced pluripotent stem cell-derived neural stem cells (iPS-NSCs) and human dental pulp mesenchymal stem cells (DPSCs) were used. The effect of nicotine on tumor tropism to glioma-conditioned medium (CM) at a non-cytotoxic concentration was assessed with Matrigel invasion assay. Nicotine effect on GJIC was assessed with the scrape loading/dye transfer (SL/DT) assay for co-culture of glioma and stem cells and the parachute assay among glioma cells using high-content analysis. Results: Tumor tropism of iPS-NSCs toward GL261-CM and DPSCs toward U251-CM was not affected by nicotine (0.1 and 1 µM). Nicotine at the concentrations equivalent to habitual smoking (1 µM) did not affect GJIC of iPS-NSC/GL261 and DPSC/U251 and GJIC among each glioma cells. Conclusions: The study demonstrated that non-cytotoxic concentrations of nicotine did not significantly change the stem cell properties requisite for stem cell-based suicide gene therapy.