Masato Hayashi

Platelet Function and Spontaneous Thrombolytic Activity of Patients with Cerebral Infarction Assessed by the Global Thrombosis Test

Measurements of platelet reactivity and assessment of the efficacy of antiplatelet drugs are widely recognized as pre-requisite for the diagnosis and treatment of stroke patients. A recently established shear-induced platelet reactivity test using non-anticoagulated blood (the Global Thrombosis Test) has facilitated measurements of physiologically relevant platelet function and thrombolytic activity. 195 healthy volunteers, not taking antiplatelet drugs or anticoagulants, and 185 patients with acute cerebrovascular diseases were enrolled. The effect of antiplatelet drugs on platelet function and thrombolytic activity was assessed using the Global Thrombosis Test after 14 days of medication. The occlusion time (OT), an index of platelet reactivity, in healthy controls was 284.9 ± 92.2 s. The lysis time (LT), an index of thrombolytic activity, in healthy controls was 2,231 ± 1,223 s. Both times had no significant difference between males and females. The OT of all stroke patients was 210.3 ± 140.8 s and was shorter than that of the healthy controls (284.9 ± 92.2, p < 0.0001). The LT of all stroke patients was 3,159 ± 1,549 s and was longer than that of the controls (2,231 ± 1,223, p < 0.0001). Medication significantly prolonged the OT from 184.5 ± 150.6 s (before) to 295.3 ± 208.1 s (after) in all patients, indicating a reversal of the hyper-platelet reactivity. In addition, medication shortened the LT from 3,924 ± 1,718 s (before) to 3,107 ± 1,794 s (after) in all patients. A prothrombotic state exists in stroke patients due to enhanced platelet function and suppressed thrombolytic activity. Medication improved these physiological parameters of haemostasis.

Cerebral and spinal cord tanycytic ependymomas in a young adult with a mutation in the NF2 gene

We studied one frontal lobe tumor and multiple spinal cord tumors (one in an extramedullary location) that had been resected from a 24‐year‐old man. The frontal lobe tumor was well demarcated and non‐infiltrating, and consisted of eosinophilic, elongated fibrillary cells arranged in a fascicular pattern. A similar histology was reproduced in the spinal cord tumors, with additional areas showing standard features of ependymoma. Immunohistochemical and ultrastructural observations revealed that all the tumors were ependymal in nature with positivity for GFAP and epithelial membrane antigen and negativity for oligodendrocyte transcription factor 2, showing intra‐ and intercellular microrosettes, leading us to a diagnosis of tanycytic ependymoma for the frontal lobe tumor and tanycytic ependymoma with ordinary ependymomatous component for the spinal cord tumors. The spinal extramedullary tumor was a schwannoma. Importantly, a heterozygous truncating mutation in the NF2 gene was identified in the blood lymphocytes from the patient. It is known that multiple nervous system tumors can occur in neurofibromatosis type 2 (NF2), which is caused by mutation in the NF2 gene, and that occurrence of ependymoma, including the tanycytic variant, can be associated with this genetic condition. The present case provides further information about the clinicopathology of tanycytic ependymoma with details of the immunohistochemical, ultrastructural and genetic features.

Carotid Endarterectomy for Patients over 80 Years Old

Objective: Carotid endarterectomy (CEA) is one of the surgical treatments for carotid artery stenosis. While a large clinical trial showed that advanced age is a risk factor for CEA, other studies reported contradictory results. The aim of this study was to evaluate the outcomes of CEA in patients aged over 80. Methods: Patients who underwent CEA between January 2012 and June 2015 in our hospital were included, and were divided into either the high age group (>80 years old) or standard group (<80 years old). CEA was the firstline surgical treatment, instead of carotid artery stenting (CAS), for all eligible cases, except where patients were not deemed amenable to general anesthesia or at patients’ request not to undergo CEA. Patient background and perioperative complications were assessed and compared statistically between the high age group and standard group. Results: Of a total of 127 patients, 20 (15.7%) were in the high age group. No significant differences in patient background were obtained between the high age group and standard group. Four (20%) cases in the high age group had perioperative complications which were all transient. No significant differences in perioperative complications were obtained between the high age group and standard group. Conclusions: It is possible for CEA to be performed safely in the elderly, provided adequate preoperative assessment of the general condition and perioperative management of patients are carried out. We recommend that CEA should not be avoided as a treatment option in the elderly, based solely on patient age.

Relationship between dyslipidemia and vascular repair after cervical artery dissection

In some cases of cervical artery dissection, vascular repair subsequently occurs at the stenotic or occluded sites. The factors responsible for this type of vascular repair remain unknown, but some reports from in vitro and animal models suggest that it is related to lipid metabolism.

Penetration of the Optic Nerve by an Unruptured Internal Carotid Artery- Ophthalmic Artery Aneurysm: Case Report

Internal Carotid Artery (ICA)-ophthalmic artery aneurysms are relatively rare aneurysms, constitute 0.3% to 1% of intracranial aneurysms and 0.9% to 6.5% of aneurysms of the ICA. Including them, large and giant aneurysms developing around the optic nerve sometimes press it and make it thin, but rarely penetrate it. There have been very few reports that they could predict the ICA-ophthalmic artery aneurysm penetrated the optic nerve with preoperative Magnetic Resonance Imaging (MRI), and it is very useful. We present a case that we could predict penetration of the optic nerve by an ICA-ophthalmic artery aneurysm before the operation, and could confirm it in the operation.