Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

The current study aimed to test whether the ratio of T1-weighted to T2-weighted signal intensity (T1W/T2W ratio: rT1/T2) derived from conventional MRI could act as a surrogate relaxation time predictive of IDH mutation status in histologically lower-grade gliomas. Strong exponential correlations were found between rT1/T2 and each of T1- and T2-relaxation times in eight subjects (rT1/T2 = 1.63exp^{−0.0005T1-relax} + 0.30 and rT1/T2 = 1.27exp^{−0.0081T2-relax} + 0.48; R² = 0.64 and 0.59, respectively). In a test cohort of 25 patients, mean rT1/T2 (mrT1/T2) was significantly higher in IDHwt tumors than in IDHmt tumors (p < 0.05) and the optimal cut-off of mrT1/T2 for discriminating IDHmt was 0.666–0.677, (AUC = 0.75, p < 0.05), which was validated in an external domestic cohort of 29 patients (AUC = 0.75, p = 0.02). However, this result was not validated in an external international cohort derived from TCIA/TCGA (AUC = 0.63, p = 0.08). The t-Distributed Stochastic Neighbor Embedding analysis revealed a greater diversity in image characteristics within the TCIA/TCGA cohort than in the two domestic cohorts. The failure of external validation in the TCIA/TCGA cohort could be attributed to its wider variety of original imaging characteristics.

DOI： 10.1038/s41598-022-23527-9

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Other Link： https://www.nature.com/articles/s41598-022-23527-9

Language：Japanese   Publisher：(一社)日本医療情報学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

Abstract

Background:

Accessibility to stroke treatments is a challenge that depends on the place of residence. However, recent advances in medical technology have improved health outcomes. Nevertheless, the geographic heterogeneity of medical resources may increase regional disparities. Therefore, evaluating spatial and temporal influences of the medical system on regional outcomes and advanced treatment of cerebral infarction are important from a health policy perspective. This spatial and temporal study aims to identify factors associated with mortality and to clarify regional disparities in cerebral infarction mortality at municipality level.

Methods:

This ecological study used public data between 2010 and 2020 from municipalities in Hokkaido, Japan. We applied spatial and temporal condition autoregression analysis in a Bayesian setting, with inference based on the Markov chain Monte Carlo simulation. The response variable was the number of deaths due to cerebral infarction (ICD-10 code: I63). The explanatory variables were healthcare accessibility and socioeconomic status.

Results:

The large number of emergency hospitals per 10,000 people (relative risk (RR) = 0.906, credible interval (Cr) = 0.861 to 0.954) was associated with low mortality. On the other hand, the large number of general hospitals per 10,000 people (RR = 1.123, Cr = 1.068 to 1.178) and longer distance to primary stroke centers (RR = 1.064, Cr = 1.014 to 1.110) were associated with high mortality. The standardized mortality ratio decreased from 2010 to 2020 in Hokkaido by approximately 44%. Regional disparity in mortality remained at the same level from 2010 to 2015, after which it narrowed by approximately 5% to 2020. After mapping, we identified municipalities with high mortality rates that emerged in Hokkaido’s central and northeastern parts.

Conclusion:

Cerebral infarction mortality rates and the disparity in Hokkaido improved during the study period (2010–2020). This study emphasized that healthcare accessibility through places such as emergency hospitals and primary stroke centers was important in determining cerebral infarction mortality at the municipality level. In addition, this study identified municipalities with high mortality rates that require healthcare policy changes. The impact of socioeconomic factors on stroke is a global challenge, and improving access to healthcare may reduce disparities in outcomes.

DOI： 10.1186/s12942-022-00316-1

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Other Link： https://link.springer.com/article/10.1186/s12942-022-00316-1/fulltext.html

Language：Japanese   Publisher：(一社)日本医療・病院管理学会  

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Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Neurosurgery Publishing Group (JNSPG)  

OBJECTIVE

“Join,” an imaging technology–based telemedicine system, allows simultaneous radiological information sharing between physically remote institutions, virtually connecting advanced medical institutions and rural hospitals. This study aimed to elucidate the health economics effect of Join for neurological telemedicine in rural areas in Hokkaido, Japan.

METHODS

Information concerning 189 requests for patient transfer from Furano Kyokai Hospital, a regional rural hospital, to Asahikawa Medical University Hospital (AMUH), an advanced academic medical institution, was retrospectively collected. The Join system was established between Furano Kyokai Hospital and AMUH in February 2019. Data collected from patients between April 2017 and December 2018 were included in the non-Join group, and those collected between February 2019 and October 2020 were included in the Join group. Clinical variables, reasons for patient transfer requests, duration of hospital stay, and medical costs per patient were analyzed between these two groups. Furthermore, clinical characteristics were compared between patients who were transferred and not transferred based on Join.

RESULTS

More patients were discharged < 7 days after transfer to AMUH in the non-Join group compared with the Join group (p = 0.02). When focusing on the Join group, more patients who were not transferred were discharged < 1 week (p < 0.01). On the other hand, more patients required surgery (p = 0.01) when transferred. The ratio of patients whose medical cost was < USD5000 substantially decreased, from 33% for the non-Join group to 13% for the Join group.

CONCLUSIONS

An imaging technology–based telemedicine system, Join, contributed to reducing unnecessary neuro-emergency patient transfer in a remote rural area, and telemedicine with an integrated smartphone system allowed medical personnel to effectively triage at a distance neuro-emergency patients requiring advanced tertiary care.

DOI： 10.3171/2022.3.focus228

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Other Link： https://thejns.org/downloadpdf/journals/neurosurg-focus/52/6/article-pE2.xml

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

OBJECTIVE: The left atrial volume index (LAVI) is considered to be the most accurate index to estimate the size of the left atrium (LA). In this study, we investigated the relationship between LA size measured by LAVI and the occurrence of large-vessel occlusion (LVO) in patients with cardiogenic cerebral infarction (CCI). METHODS: This retrospective single-center cohort study involved 118 patients with CCI within the internal carotid artery (ICA) or middle cerebral artery regions seen between January 2015 and July 2020. In all patients, the type of CCI was determined according to the Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Scores (TOAST) subtype diagnosis criteria. LVO was defined as positive when magnetic resonance imaging and computed tomography angiography showed ICA, M1, or M2 occlusion, with all others defined as non-LVO. Clinical characteristics, including LAVI, were evaluated in the records of several patients to investigate if they were risk factors for developing LVO. RESULTS: Seventy patients (59%) were diagnosed as having LVO infarction (ICA occlusion, n = 19 [16%]; M1 occlusion, n = 26 [22%]; and M2 occlusion, n = 25 [21%]). Echocardiography showed no difference between LVO and non-LVO in terms of the ejection fraction (P = 0.64), LA dimension (P = 0.93), and LA volume (P = 0.06). However, LAVI significantly differed between the LVO and non-LVO groups (P = 0.02). Multivariate logistic regression analysis showed larger LAVI as a significant risk factor for LVO (P = 0.01). CONCLUSIONS: Our findings suggest that a larger LAVI is a predictor of developing LVO in patients with CCI.

DOI： 10.1016/j.wneu.2021.12.003

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Publishing type：Research paper (scientific journal)   Publisher：Japan Stroke Society  

DOI： 10.3995/jstroke.10887

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Publishing type：Research paper (scientific journal)   Publisher：Oxford University Press (OUP)  

Abstract

Isolated spontaneous common carotid artery (CCA) dissection is extremely rare. Moreover, only a few case reports for isolated spontaneous CCA dissection treated with carotid artery stenting (CAS) can be found so far. Here, the authors report a case where intravascular ultrasonography (IVUS) provided valuable information about lesion evaluation, stent selection and stent placement during CAS for isolated CCA dissection. A 69-year-old male was diagnosed with an isolated spontaneous left CCA dissection. CAS assisted with IVUS was performed to prevent further dissection and cerebral infarction recurrence. To the best of our knowledge, this is the first case report of an isolated spontaneous CCA dissection treated with CAS assisted by IVUS. CAS assisted by IVUS may be an effective treatment option to prevent intraoperative complications and further stroke recurrence for isolated spontaneous CCA dissection.

DOI： 10.1093/jscr/rjab232

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Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Turkish Neurosurgical Society  

DOI： 10.5137/1019-5149.jtn.31089-20.2

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Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

DOI： 10.1080/02688697.2020.1817316

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：SAGE Publications  

Purpose

Although some authors proposed that coil embolization in middle cerebral artery (MCA) aneurysms is a useful and effective alternative, the characteristics of the aneurysms may be different at each location. We compared the results of coil embolization of proximal middle cerebral artery aneurysms with those of other middle cerebral artery aneurysms.

Methods

Data from 46 patients with 50 aneurysms were retrospectively evaluated. We defined the aneurysms inside of the insular cortex as proximal MCA (pMCA) aneurysms and those outside of the insular cortex as non-proximal MCA (npMCA) aneurysms. The results of the occlusion were divided into classes 1, 2, and 3 of the Raymond scale. We collected the results of the occlusion from the operative notes supplied by a neuroendovascular specialist.

Results

Univariate analysis identified favorable results for pMCA aneurysms (class 1: pMCA = 22 npMCA = 11; P < 0.01). In the radiological follow-up results, we achieved class 1 in 29 patients (69%; pMCA = 21 and npMCA = 8; P < 0.01). Side wall type aneurysms (pMCA = 14, npMCA = 2; P < 0.01) and the number of branches from the neck of ≤1 (pMCA = 14, npMCA = 2; P < 0.01) were significantly recognized at the pMCA.

Conclusions

Proximal middle cerebral artery aneurysm clipping is difficult because the origin of the lenticulostriate arteries is often hidden behind the aneurysmal dome. In the present study, endovascular coil embolization for pMCA aneurysms obtained better results than that for npMCA aneurysms because of the morphological characteristics. Endovascular coil embolization seems to be efficacious for pMCA aneurysms as compared with npMCA aneurysms.

DOI： 10.1177/1591019919896459

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Other Link： http://journals.sagepub.com/doi/full-xml/10.1177/1591019919896459

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

BACKGROUND: Persistent primitive trigeminal artery (PPTA), which is a fetal carotid-basilar anastomosis, is the most common embryologic vascular remnant persisting in adults. Aneurysms can arise between the internal carotid artery (ICA) and PPTA. Here we present a case of ICA-PPTA aneurysm treated with a flow-diverter stent. CASE DESCRIPTION: A 52-year-old woman had left abducens nerve palsy. Imaging detected a large left ICA-PPTA aneurysm, which we chose to treat with a flow-diverter stent after embolizing the PPTA with a coil. Although the abducens nerve palsy did not change, there were no signs of cerebral infarction, and no new symptoms appeared postoperatively. Blood flow in the aneurysm had disappeared on digital subtraction angiography after 6 months. CONCLUSIONS: This is the first case report of ICA-PPTA aneurysm successfully treated with a flow-diverter stent. We could stop blood flow from the posterior circulation by embolizing the PPTA with a coil, allowing the use of a flow-diverter stent. This report can be used as a reference for the procedure in future work.

DOI： 10.1016/j.wneu.2019.08.199

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Authorship：Lead author,　Corresponding author   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.wneu.2019.02.079

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Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Informa UK Limited  

We report a case of a primary malignant lymphoma of the trigeminal nerve that was associated with facial pain. A 65-year-old man was examined at another hospital for unilateral facial pain. Carbamazepine was prescribed, but his symptoms did not improve. Magnetic resonance imaging (MRI) revealed swelling of the trigeminal nerve and a mass lesion in Meckel's cave. The patient was referred to our hospital at this point. Gadolinium-enhanced MRI and F18-Fluorodeoxyglucose-position emission tomography suggested a likely malignant tumour and a biopsy was performed. Histopathological examination showed diffuse a large B cell lymphoma. The patient was treated with high-dose methotrexate (HD-MTX) and radiotherapy. Despite responding well to initial treatment, the patient relapsed, with lymphoma observed throughout the body. He died of pneumonia 18 months after the initial diagnosis. Facial pain is a symptom that is commonly managed in general practice. If symptoms do not improve, repeated imaging studies, including contrast MRI, is warranted. This is the first reported case of primary neurolymphomatosis (NL) of the trigeminal nerve associated with facial pain alone. Furthermore, HD-MTX and radiotherapy may be considered for the management of primary NL of a cranial nerve.

DOI： 10.1080/02688697.2019.1568391

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

OBJECTIVE: Surgical or endovascular treatment for giant or complex aneurysms is challenging. The aims of this study were to evaluate clinical outcomes and factors affecting the prognosis of giant or complex aneurysms and to better establish the role of microsurgery in the management strategy. METHODS: One hundred fifty-nine patients with surgically treated complex aneurysms were included. Thirty-two patients (20.1%) had giant aneurysms (≥25 mm) and 57 (35.8%) had large aneurysms (≥15 mm). Poor outcome was defined as modified Rankin Scale scores of 3-6. RESULTS: The mean aneurysm size was 17.0 mm (range, 1.6-47.5 mm). One hundred and sixteen aneurysms (80.0%) were in the anterior circulation and 43 (27.0%) were in the posterior circulation. One hundred and thirty-eight (86.8%) aneurysms were completely occluded without residual aneurysms. Nineteen (11.9%) had minor aneurysm remnants; 2 (1.3%) had incomplete occlusion. Two patients (1.3%) with giant basilar artery (BA) trunk aneurysms experienced rupture of the treated aneurysm and died. Bypass surgery was combined with microsurgery in 148 patients (93.1%). Perforating artery infarction was observed postoperatively in 42 patients (26.4%), and poor outcome was observed in 29 (18.2%). Male sex (P = 0.016; adjusted odds ratio [OR], 4.524 [1.949-10.500]), perforating artery infarction (P < 0.001; adjusted OR, 13.625 [5.329-34.837]), and BA aneurysm location (P = 0.003; adjusted OR, 56.333 [6.830-464.657]) were significantly related to poor outcome. The aneurysm size (P = 0.017; adjusted OR, 1.064 [1.021-1.107]), C1 aneurysm location (P = 0.042; adjusted OR, 2.591 [0.986-6.811]), and BA aneurysm location (P = 0.033; adjusted OR, 12.956 [3.197-52.505]) were significantly related to perforating artery infarction. CONCLUSIONS: Microsurgery with bypass is effective for many different complex aneurysms, except BA aneurysms.

DOI： 10.1016/j.wneu.2018.04.007

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