Mechanical Thrombectomy for Basilar Artery Occlusion with a Type 1 Persistent Proatlantal Artery: A Case Report and Literature Review.

Objective: Persistent proatlantal artery (PPA) is a primitive carotid-vertebrobasilar anastomosis (CVA); acute ischemic stroke due to basilar artery (BA) occlusion via a PPA is extremely rare. Case Presentation: An 84-year-old female developed disturbance of consciousness (Glasgow Coma Scale E2V1M5) and quadriparesis with a National Institutes of Health Stroke Scale score of 35. Head CT revealed early ischemic changes in the right temporal lobe, and a hyperdense vessel sign in the BA. Cerebral angiography showed that the left vertebral artery (VA) did not originate from the left subclavian artery or aortic arch. A left common carotid artery angiogram showed the presence of the left PPA originating from the left external carotid artery. Mechanical thrombectomy (MT) with contact aspiration using a Penumbra 5MAX ACE 60 aspiration catheter was performed, and successful recanalization was achieved after clot retrieval in the first attempt (thrombolysis in cerebral infarction scale 2b). MRI performed the following day, however, revealed a newly developed large hemorrhagic infarction in the pons, with no improvement in her symptoms (modified Rankin Scale score of 5 at 90 days). Conclusion: Although MT achieved successful recanalization of the BA via the PPA, her clinical symptoms did not improve, probably because of poor collateral circulation or the long length of the occlusion. In patients with acute vertebro-BA occlusion, if the VA does not originate from the subclavian artery or aortic arch, the presence of a primitive CVA should be considered.

Pilocytic astrocytoma of the optic nerve with intracystic hemorrhage in an adult: illustrative case.

BACKGROUND: Optic pathway gliomas are uncommon, accounting for 3-5% of childhood brain tumors, and are mostly classified as pilocytic astrocytomas (PAs). PAs of the optic nerve are particularly rare in adults. OBSERVATIONS: The authors presented the case of PA of the left optic nerve in a 49-year-old woman along with detailed pathological and molecular analyses and sequential magnetic resonance imaging. The tumor had progressed during 5 years of follow-up along with cyst formation and intracystic hemorrhage; it had a thick capsule and contained xanthochromic fluid. The boundary between tumor and optic nerve was unclear. B-type Raf kinase (BRAF) V600E point mutations or translocations, IDH1-R132H mutations, loss of alpha-thalassemia/mental retardation X-linked, and 1p/19q codeletion were negative. LESSONS: BRAF alterations in pediatric PAs of the optic nerve are less frequent than those observed in PAs in other lesions; the same molecular pattern was observed in the adult case, without changes in BRAF. Surgical management should be indicated only in cases with severely impaired vision or disfigurement because there is no clear border between the tumor and optic nerve. Further discussion is needed to optimize the treatment for adult optic pathway gliomas, including radiotherapy, chemotherapy, and molecular-targeted therapies, in addition to surgical intervention.

Results of Mechanical Thrombectomy in Patients Aged ≥80 Years.

Objective: The effectiveness of mechanical thrombectomy (MT) for anterior circulation large vessel occlusion (LVO) is controversial in elderly patients. The aim of this study was to evaluate the efficacy of MT in octogenarians. Methods: One hundred and sixty-five patients who underwent MT for anterior circulation LVO between May 2014 and August 2019 at our institution were evaluated. Patients were divided into two groups, the elderly group (≥80 years) and non-elderly group (<80 years), and we compared the effective recanalization rate (Thrombolysis in Cerebral Infarction 2b-3), good outcome rate (modified Rankin Scale 0-2 at 90 days), time from groin puncture to recanalization (P to R), symptomatic intracranial hemorrhage (sICH), and mortality rate between them retrospectively. Eligible patients for MT were judged using the Japanese stroke guidelines, and the selection criteria were more carefully applied to elderly patients. Results: MT was performed on 48 elderly patients (29.1%) and 117 non-elderly patients (70.9%). On the other hand, 10 elderly patients (19.6%) and 5 non-elderly patients (5.4%) did not undergo MT even though they met the inclusion criteria. There were significantly fewer male patients and smokers in the elderly group, but other baseline and clinical characteristics were not significantly different between the groups. Effective recanalization (elderly 93.8% vs non-elderly 91.5%), good outcome (45.8% vs 60.7%), P to R (33.5 minutes vs 33.5 minutes), sICH (2.1% vs 4.3%), and mortality (8.3% vs 2.6%) were not significantly different between the two groups. Conclusion: When recanalization was achieved by strict preoperative evaluation of clinical conditions and imaging, MT may be safe and effective even for octogenarians or older patients.

Toxicological Evaluation of SiO2 Nanoparticles by Zebrafish Embryo Toxicity Test.

As the use of nanoparticles (NPs) is increasing, the potential toxicity and behavior of NPs in living systems need to be better understood. Our goal was to evaluate the developmental toxicity and bio-distribution of two different sizes of fluorescently-labeled SiO2 NPs, 25 and 115 nm, with neutral surface charge or with different surface functionalization, rendering them positively or negatively charged, in order to predict the effect of NPs in humans. We performed a zebrafish embryo toxicity test (ZFET) by exposing the embryos to SiO2 NPs starting from six hours post fertilization (hpf). Survival rate, hatching time, and gross morphological changes were assessed at 12, 24, 36, 48, 60, and 72 hpf. We evaluated the effect of NPs on angiogenesis by counting the number of sub-intestinal vessels between the second and seventh intersegmental vessels and gene expression analysis of vascular endothelial growth factor (VEGF) and VEGF receptors at 72 hpf. SiO2 NPs did not show any adverse effects on survival rate, hatching time, gross morphology, or physiological angiogenesis. We found that SiO2 NPs were trapped by the chorion up until to the hatching stage. After chemical removal of the chorion (dechorionation), positively surface-charged SiO2 NPs (25 nm) significantly reduced the survival rate of the fish compared to the control group. These results indicate that zebrafish chorion acts as a physical barrier against SiO2 NPs, and removing the chorions in ZFET might be necessary for evaluation of toxicity of NPs.