Relationship between cerebral hyperperfusion syndrome and the immediate change of cerebral blood flow after carotid artery stenting evaluated by single-photon emission computed tomography.

PURPOSE: Cerebral hyperperfusion syndrome (CHS) is a critical complication after carotid artery stenting (CAS). However, few CAS studies have evaluated immediate and temporary changes in ipsilateral cerebral blood flow (CBF) quantitatively. The study was performed to evaluate immediate changes in CBF after CAS and subsequent CBF changes in patients with cerebral hyperperfusion (HP) using 123I-IMP SPECT. METHODS: The subjects were 223 patients with chronic extracranial carotid artery stenosis who underwent CAS in our department between March 2010 and March 2020. Quantitative CBF and cerebrovascular reactivity to acetazolamide in the middle cerebral artery were assessed before CAS by 123I-IMP SPECT. CBF was also measured immediately after CAS by 123I-IMP SPECT. When HP was detected, CBF was measured again 3 and 7 days after CAS. RESULTS: The median (interquartile range) ipsilateral quantitative CBF change after CAS was - 0.1% (- 9.5-8.2%), and the upper value of the 95% CI of the quantitative CBF change was 48.2%. Thus, we defined HP after CAS as an increase in quantitative CBF of > 48.2% compared with the preoperative value. Of 223 patients, 5 (2.2%) had HP, and 4 of these patients (80%) developed CHS. In the CHS patients, HP was maintained for about 3 days and improved after about 7 days. CONCLUSION: An immediate CBF increase of > 48.2% after CAS may lead to development of CHS. In CHS after CAS, HP persisted for about 1 week and postoperative management may be required for at least 1 week.

Alpha emitter detection systems using a UV light detector.

To visualize alpha contamination, an alpha-particle detection system has been developed that is capable of detecting alpha-induced UV lights from a few meters distance in dark environments. It detects UV lights from ionized nitrogen with a photomultiplier tube. To identify the contaminated spot quickly, large diameter lenses were designed and tested.

Timing of Direct Oral Anticoagulants for Hemorrhagic Transformation After Endovascular Treatment in Acute Ischemic Stroke.

OBJECTIVES: The purpose of this study is to investigate the relationship between the timing of starting direct oral anticoagulants (DOACs) and subsequent clinical outcomes in patients with hemorrhagic transformation (HT) after endovascular treatment (EVT). MATERIALS AND METHODS: The subjects were patients with acute cardioembolic stroke who underwent EVT and received DOACs in our department from February 2017 to August 2021. Based on CT at 24 h after EVT, the patients were classified using European Collaborative Acute Stroke Study criteria into three groups: no HT, hemorrhagic infarction (HI), and parenchymal hematoma (PH). Outcomes were assessed for incidence of recurrent ischemic stroke (RIS), new intracranial hemorrhage (ICH), and worsened HT associated with DOACs. RESULTS: Of 111 patients, 29 (26.1%) had HT, including 16 (14.4%) with HI and 13 (11.7%) with PH. The start of DOACs was significantly delayed in the PH group (no HT: 1.0 (1.0-3.0) days vs. HI: 3.0 (2.0-5.0) days vs. PH: 7.0 (7.0-10.0) days, P < 0.01). The incidence of RIS did not differ significantly among the three groups, but tended to be higher in the PH group (no HT: 3.7% vs. HI: 6.3% vs. PH: 15.4%, p = 0.12). There were no cases of new symptomatic ICH. New asymptomatic ICH occurred in 2 cases in the no HT group. Worsened HT after initiation of DOACs did not occur in the HI or PH group. CONCLUSIONS: The timing of starting DOACs in patients with HT after EVT may be divided by subtypes of HI and PH. In patients with HI, early initiation of DOACs can prevent RIS and is unlikely to cause new ICH or worsened HI. In PH, initiation of DOACs within 14 days appears to be safe and does not exacerbate PH. The later the start of DOACs, the higher the frequency of RIS, so early initiation of DOACs is desirable.

Cilostazol decreases duration of spreading depolarization and spreading ischemia after aneurysmal subarachnoid hemorrhage.

OBJECTIVE: Traditionally, angiographic vasospasm (aVS) has been thought to cause delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH). However, successful treatment of aVS alone does not result in improved neurological outcome. Therefore, there may be other potential causes of poor neurological outcome, including spreading depolarization (SD). A recent study showed beneficial effects of cilostazol on DCI and neurological outcome. The present prospective clinical trial and experimental study focused on effects of cilostazol on SDs. METHODS: Fifty aSAH patients were treated with clip ligation and randomly assigned to a cilostazol (n = 23) or control group (n = 27). Effects of cilostazol on DCI, aVS, and SDs, measured with subdural electrodes, were examined. The effect of cilostazol on SD-induced perfusion deficits (spreading ischemia) was assessed in an aSAH-mimicking model. RESULTS: There was a trend for less DCI in the cilostazol group, but it did not reach our threshold for statistical significance (13.0% vs 40.0%, odds ratio = 0.266, 95% confidence interval [CI] = 0.059-1.192, p = 0.084). However, the total SD-induced depression duration per recording day (22.2 vs 30.2 minutes, ß = -251.905, 95% CI = -488.458 to -15.356, p = 0.043) and the occurrence of isoelectric SDs (0 vs 4 patients, ß = -0.916, 95% CI = -1.746 to -0.085, p = 0.037) were significantly lower in the cilostazol group. In rats, cilostazol significantly shortened SD-induced spreading ischemia compared to vehicle (Student t test, difference = 30.2, 95% CI = 5.3-55.1, p = 0.020). INTERPRETATION: Repair of the neurovascular response to SDs by cilostazol, as demonstrated in the aSAH-mimicking model, may be a promising therapy to control DCI. Ann Neurol 2018;84:873-885.

Cerebral infarction associated with benign mucin-producing adenomyosis: report of two cases.

BACKGROUND: Cerebral infarction associated with a malignant tumor is widely recognized as Trousseau syndrome. In contrast, few cases of cerebral infarction associated with benign tumors have been reported. We present two cases of embolic stroke that seemed to be caused by mucin-producing adenomyosis. CASE PRESENTATION: The patients were women aged 42 and 50 years old. Both patients developed right hemiparesis and aphasia, and cerebral infarctions were detected in the left cerebral hemisphere. There were no other abnormal findings, except for elevation of CA125 and D-dimer. Trousseau syndrome was suspected in both cases, but whole body examinations did not reveal any malignant tumors. However, uterine adenomyosis was detected in both patients. CONCLUSIONS: From our findings and a review of the literature, both mucin-producing malignant tumors and mucin-producing benign tumors such as adenomyosis may cause hypercoagulability and cerebral infarction. This mechanism should be considered in a case of a young to middle-aged woman with embolic stroke of an undetermined origin.

Safety of Tailored Transfemoral Carotid Artery Stenting for Symptomatic Elderly Patients: A Single Center Observational Study.

OBJECTIVE: Transfemoral carotid artery stenting (TFCAS) in symptomatic elderly patients (≥70 years old) may have a high periprocedural stroke rate. This study was performed to examine whether tailored TFCAS for symptomatic elderly patients is as safe as that for symptomatic nonelderly patients. METHODS: The subjects were 185 patients with symptomatic internal carotid artery stenosis. Tailored TFCAS including postoperative management was performed based on preoperative examinations of vascular anatomy, plaque imaging, platelet aggregation activity, and cerebral hemodynamic impairment. The major 30-day perioperative stroke rates were examined. RESULTS: The patients included 51 (27.6%) <70 (group Y) and 134 (72.4%) ≥70 (group E) years old. Group E included significantly more cases with an elongated aortic arch, tortuous target lesion, and longer plaques (all P < 0.05). Among all cases, 181 (97.8%) procedures were performed as per preoperative planning. Group E had more frequent use of a proximal embolic protection device and a closed-cell or dual-layer micromesh stent (all P < 0.05). Seven patients (3.8%) had major stroke. Rates of major ischemic stroke (2.0% vs. 3.0%, P = 1.00) and intracranial hemorrhage (2.0% vs. 0.8%, P = 0.48) were low and did not differ significantly between groups Y and E. CONCLUSIONS: Symptomatic elderly patients have several unfavorable factors. However, tailored TFCAS for each patient based on preoperative examinations in symptomatic elderly patients may be as safe as that in symptomatic nonelderly patients.

Impact of Frailty on Medium-Term Outcome in Asymptomatic Patients After Carotid Artery Stenting.

OBJECTIVE: There are few reports on the relationship between carotid artery stenting (CAS) and frailty. In this study, medium-term outcome after CAS in patients with asymptomatic carotid artery stenosis was examined to see the effect of frailty itself. METHODS: A retrospective study was performed in 71 consecutive patients who were treated with CAS for asymptomatic lesions from January 2007 to June 2014. In this study, only patients without neurologic symptoms before treatment were included. Frailty was defined on the basis of the presence of ≥2 of the 5 items on the Cardiovascular Health Study (CHS) Index. The relationship of frailty with a composite endpoint of the incidence of stroke, disease requiring hospital admission, and death for 3 years after CAS was examined. RESULTS: There were 23 cases (average age 73.9 years, median CHS index 3) with frailty and 48 (average age 70.9 years, median CHS index 0) without frailty. There were no differences in comorbidities or CAS perioperative complications between these groups. However, there was a significantly higher incidence of the composite endpoint in patients with frailty (13/23 vs. 4/48, P < 0.001), and in multivariate analysis, frailty was strongly associated with this endpoint (odds ratio 28.24, 95% confidence interval 4.62-172.71). CONCLUSIONS: In CAS conducted for asymptomatic lesions, perioperative complications had no relationship with frailty. However, frailty is likely to be associated with lower activity of daily life in the medium term after CAS, and consideration of underlying diseases is required in patients with frailty.