Impact of COVID-19 and Closed Transmission of SARS-CoV-2 during the First Wave in Toyama Prefecture, Japan, March 30 to May 18, 2020.

We studied 226 patients in Toyama Prefecture who were notified of COVID-19 during the first wave between March 30 and May 18, 2020. Of the 226 patients, 22 (9.7%) died, most (95%) of whom were aged ≥65 years. A large cluster comprising 59 patients (41 residents and 18 staff members) was identified in a nursing home on April 17. No deaths occurred among staff members; however, 12 of the 41 residents (29%) died. Although the threshold cycle (Ct) values were significantly lower in the 20-64 and ≥65 years age groups than in the <20 years age group, no correlation was found between the Ct values and severity, fatal outcome, or secondary infection. The haplotype network of 145 SARS-CoV-2 isolates (64%) from 226 patients was analyzed. The viral genomes of the case groups differed by less than five nucleotide bases. These data suggest that the SARS-CoV-2 strains, which were initially introduced into Toyama Prefecture in late March and early April 2020, and their closely related strains, identified as lineage B.1.1, circulated during the first wave. The reduced inter-prefectural mobility of local residents may support the lack of strain diversity in SARS-CoV-2 during the first wave of the state of emergency.

Intravenous Thrombolysis Improved Aphemia and Confirmed the Dominant Precentral Gyrus as the Responsible Lesion.

Aphemia is now considered an impairment of speech production. We present a case of an 89-year-old right-handed woman who received intravenous thrombolysis with a recombinant tissue plasminogen activator for the ischemic symptom "loss of speech" and recovered with an ischemic lesion of the left precentral gyrus. The patient had untreated atrial fibrillation. Neurological examination showed that her level of consciousness was alert, with normal comprehension and mild lower facial droop. Head computed tomography (CT) did not reveal a hemorrhagic lesion. To treat the acute ischemic stroke, she received a recombinant tissue plasminogen activator. Just after thrombolysis, she started to speak. Then, magnetic resonance imaging (MRI) revealed an acute ischemic infarction in the dominant precentral gyrus. Follow-up MRI revealed the peripheral middle cerebral artery territory infarction in the left precentral gyrus, but she still could speak. The symptom of "loss of speech" was considered aphemia. By intravenous thrombolysis, impaired speech production in our patient was believed to be caused by an infarction in the dominant precentral gyrus. This case also demonstrated that the rare clinical symptom was due to an ischemic stroke in the territory of the distal middle cerebral artery. Clinicians who engage in stroke care need to know the rare symptoms of aphemia in the era when mechanical thrombectomy could be considered a promising treatment option for distal medium vessel occlusion.

Walk-In Hospital Admission of Patients with Subarachnoid Hemorrhage: Clinical Presentation and Outcome.

OBJECTIVE: Neurosurgeons occasionally encounter cases of subarachnoid hemorrhage (SAH) in admitted walk-in patients, termed "walk-in SAH." However, their clinical characteristics have not been fully understood. We thus, aimed to investigate several characteristics of patients with walk-in SAH and compare them with those of patients with good grade SAH who arrived at the hospital by ambulance. METHODS: Between January 2011 and January 2018, consecutive patients with World Federation of Neurosurgical Society (WFNS) grade I and II aneurysmal SAH were enrolled. They were dichotomized into walk-in and ambulance groups, and their demographic and disease-related characteristics were compared. Furthermore, predictors associated with unfavorable outcomes were investigated in patients with walk-in SAH. RESULTS: Of 171 patients with World Federation of Neurosurgical Society grade I and II SAH, 68 (39.8%) were categorized as walk-in SAH. The mean time for diagnosis in patients with walk-in SAH was significantly longer than that in patients who arrived by ambulance (P < 0.01). Multivariate analysis demonstrated that a lower rate of hypertension, high grades on the Barrow Neurological Institute scale, and Early Brain Edema Score were significantly associated with walk-in SAH (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.21-0.91, P = 0.03; OR 0.32, 95% CI 0.13-0.76, P = 0.007; OR 0.11, 95% CI 0.02-0.51, P < 0.0001, respectively). Additionally, severe angiographic vasospasm was a significant predictor of unfavorable outcomes in walk-in SAH (OR 37.7, 95% CI 1.10-1290.90, P = 0.04). CONCLUSIONS: Patients with walk-in SAH exhibit radiological characteristics associated with a more favorable outcome among patients with good grade SAH. Therefore, these patients may have a positive prognosis.

Predictive Factors of Functional Outcome in World Federation of Neurosurgical Societies Grade V Subarachnoid Hemorrhage.

OBJECTIVE: Patients with World Federation of Neurosurgical Societies (WFNS) grade V subarachnoid hemorrhage (SAH) frequently have poor outcomes. The current understanding of the predictors of functional outcome only in WFNS grade V SAH is limited. METHODS: Patients with WFNS grade V SAH were retrospectively analyzed between April 2008 and August 2019. Surgical treatment is commonly delayed until clinical improvement is observed using a less aggressive approach. Clinical and radiologic data on admission were assessed, and disease-related characteristics were compared between patients with favorable outcomes (modified Rankin Scale score 0-3) and those with unfavorable outcomes (modified Rankin Scale score 4-6). RESULTS: A total of 144 patients were included, and 22 patients (15.3%) achieved favorable outcomes, whereas 122 patients (84.7%) had unfavorable outcomes. Surgical aneurysm repair was performed in all patients with favorable outcomes and in 21.3% of those with unfavorable outcomes. Multivariate analysis showed that Glasgow Coma Scale score of 3, high-grade Early Brain Edema Score, absence of bilaterally light reflex and neurologic improvement, and hypertension were significantly associated with unfavorable outcomes (odds ratio [OR], 9.54, P = 0.03; OR, 5.37, P = 0.04; OR, 11.80, P = 0.009; OR, 0.14, P = 0.02 and OR, 6.53, P = 0.04, respectively). CONCLUSIONS: The final outcome of patients with WFNS grade V SAH was still poor and highly predicted by Glasgow Coma Scale score of 3, high-grade Early Brain Edema Score, absence of bilaterally light reflex and neurologic improvement, and a history of hypertension. The efficacy of aggressive surgical treatment for these patients remains controversial, and the indications should be clearly defined in patients with desolate clinical status on admission.

Viral isolation analysis of SARS-CoV-2 from clinical specimens of COVID-19 patients.

Genetic testing using reverse transcriptase real-time polymerase chain reaction (rRT-PCR) is the mainstay of diagnosis of COVID-19. However, it has not been fully investigated whether infectious viruses are contained in SARS-CoV-2 genome-positive specimens examined using the rRT-PCR test. In this study, we examined the correlation between the threshold Cycle (Ct) value obtained from the rRT-PCR test and virus isolation in cultured cells, using 533 consecutive clinical specimens of COVID-19 patients. The virus was isolated from specimens with a Ct value of less than 30 cycles, and the lower the Ct value, the more efficient the isolation rate. A cytopathic effect due to herpes simplex virus type 1 contamination was observed in one sample with a Ct value of 35 cycles. In a comparison of VeroE6/TMPRSS2 cells and VeroE6 cells used for virus isolation, VeroE6/TMPRSS2 cells isolated the virus 1.7 times more efficiently than VeroE6 cells. There was no significant difference between the two cells in the mean Ct value of the detectable sample. In conclusion, Lower Ct values in the PCR test were associated with higher virus isolation rates, and VeroE6/TMPRSS2 cells were able to isolate viruses more efficiently than VeroE6 cells.

[An Intraabdominal Hemorrhage Affected by Catecholamine Surges Caused by Subarachnoid Hemorrhage:A Case Report].

Intraabdominal hemorrhage is a rare complication of subarachnoid hemorrhage(SAH). Recently, there have been a number of reports about the coexistence of intracranial and Intraabdominal aneurysms caused by segmental arterial mediolysis(SAM). The etiology of SAM is still unclear, but catecholamine is known to be one of the causes of SAM. The authors report a rare case in which an increase of catecholamine by SAH affected the Intraabdominal hemorrhage during the perioperative period of SAH. A 67-year-old woman was admitted to our hospital with SAH. Cerebral angiography revealed a right internal carotid-posterior communicating artery aneurysm, and an emergent neck clipping was performed. The intraoperative finding was a saccular aneurysm with a partial red wall of the internal carotid artery. Thirteen days after SAH, the patient complained of abdominal pain, but there were no particular findings on abdominal CT. The next day, anemia progressed suddenly because of Intraabdominal hemorrhage caused by rupture of the splenic artery aneurysm. She developed shock and consciousness disturbance, and left hemiparesis due to vasospasm appeared. She recovered from shock after receiving transfusion and coil embolization of the splenic artery aneurysm. Her consciousness and left hemiparesis improved after two months of rehabilitation. The radiological findings of the splenic artery aneurysm are compatible with SAM. We believe that an increase in catecholamine by SAH affected the development and rupture of the splenic artery aneurysm. In cases of SAH with abdominal pain, a detailed examination of the abdomen might be needed, and the use of catecholamine for symptomatic vasospasm should be carefully performed.

Anatomical Variations of Vertebrobasilar Artery are Closely Related to the Occurrence of Vertebral Artery Dissection-An MR Angiography Study.

GOAL: Intracranial arterial dissection is a major cause of ischemic stroke and subarachnoid hemorrhage in relatively young patients. We assessed the hypothesis that the tortuosity of the vertebrobasilar artery is associated with the occurrence of vertebral artery (VA) dissection, using MR angiography (MRA). MATERIALS AND METHODS: This study enrolled 43 patients with VA dissection, and 63 age- and sex-matched healthy subjects were used as the controls. MRA was employed to evaluate the presence of dominant VA and the lateral shift of vertebrobasilar junction in both groups. The VA diameters were considered different when the difference was greater than .3 mm. These anatomical variations were divided into 3 types: Type 1 (vertebrobasilar junction within 2 mm from the midline), Type 2 (>2 mm-lateral shift of vertebrobasilar junction to the ipsilateral side of the dominant VA), and Type 3 (>2 mm-lateral shift of vertebrobasilar junction to the contralateral side of the dominant VA). FINDINGS: The presence of dominant VA and the lateral shift of vertebrobasilar junction were more prevalent in patients with VA dissection than in the controls (OR: 3.46, P = .013, and OR: 4.51, P = .001, respectively). The lateral shift of vertebrobasilar junction was classified into Type 1 (n = 6), Type 2 (n = 13), and Type 3 (n = 17) among patients with VA dissection, while into Type 1 (n = 20), Type 2 (n = 8), and Type 3 (n = 7) among the controls. Type 3 predominance was observed in patients with VA dissection (P = .02). CONCLUSIONS: Anatomical variations of the vertebrobasilar artery may play an important role in the occurrence of VA dissection.

[The Analysis of the Thickness of a Cerebral Aneurysm:Can Predict the Translucent-type of Unruptured Middle Cerebral Artery Aneurysm Preoperatively?]

OBJECT: The rupture risk of cerebral aneurysms is determined by various factors. However, it is not clear whether the thickness of the aneurysm wall also influences the rupture risk. In this study, under the assumption that thin-walled aneurysms have a higher rupture risk compared with thick-wall aneurysms, we evaluate the usefulness of computed fluid dynamics(CFD)to identify thin-walled cerebral aneurysms. METHODS: Fifty-four unruptured middle cerebral aneurysms from 53 patients were analyzed using CFD before the operation. We divided these aneurysms into two groups: translucent-type aneurysms and others. To analyze the difference of these groups, individual elements(age, gender, volume, and aspect ratio)and hemodynamic factors(wall shear stress[WSS], flow coefficient, and flow coefficient per volume)were examined using CFD. RESULTS: Univariate analysis detected significant relationships between the translucent-type aneurysms and gender, aspect ratio, WSS and flow coefficient per volume. Multiple logistics regression also identified a significant relationship with gender and flow coefficient per volume. The receiver operating characteristic curve demonstrated that the flow coefficient per volume could predict translucent-type aneurysms(area under the curve 0.84, cut-off value 1.32, sensitivity 76.2%, and specificity 87.9%). CONCLUSION: Gender and the flow coefficient per volume could predict translucent-type aneurysms of the middle cerebral artery. CFD analysis might be a useful tool to predict translucent-type aneurysms.

Correlation Between Cerebral Microbleeds and Vulnerable Plaque in Patients with Severe Carotid Artery Stenosis; Comparative Magnetic Resonance Imaging Study.

GOAL: There are an increasing idea that the inflammation contributes to vascular diseases in various organs. The pathogenesis of both cerebral small vessel disease such as cerebral microbleeds and carotid plaque may be associated with chronic inflammation. This study was aimed to evaluate the correlation between microbleeds and carotid plaque characteristics. MATERIALS AND METHODS: This study enrolled 85 patients who underwent surgical/endovascular treatments for carotid artery stenosis between January 2009 and July 2016. Their clinical data were precisely analyzed. T2*-weighted magnetic resonance (MR) imaging was performed to detect the cerebral microbleeds. The carotid plaque with high signal intensity on T1-weighted MR imaging was categorized into vulnerable plaque. FINDINGS: The microbleeds was detected in 17 of 85 (20%). The prevalence of vulnerable carotid plaque and previous symptomatic lacunar infarction was significantly greater in the patients with microbleeds than in those without (P = .001 and P = .03, respectively). Multiple logistic regression analysis showed that the vulnerable plaque was significantly associated with the presence of microbleeds when adjusted for age, alcohol intake, antiplatelet drug use, the presence of previous symptomatic lacunar infarction, and coronary artery disease (P = .009, OR = 5.38, 95% CI = 1.51-21.0). CONCLUSIONS: These findings suggest the correlation between microbleeds and vulnerable plaque in patients with severe (>70%) carotid artery stenosis. Systemic, chronic inflammation may play a key role in both small and large arteries' disease of the brain. The knowledge may be valuable to fully understand the entity of cerebrovascular diseases as one of systemic, chronic inflammation.

Boundary EEG Asymmetry Is Associated to Linguistic Competence in Vascular Cognitive Impairments.

Background and Purpose: We recently noted a gradual change in the boundary electroencephalography (EEG) oscillation of 7.8 Hz between theta (θ) and alpha (α) bands in response to increased atherosclerosis levels in the elderly. The aim of this study was to investigate the role of boundary EEG oscillations of θ-α bands on cognitive functions in vascular cognitive impairments (VCI) patients. Materials and Methods: We examined 55 patients with VCI in carotid stenosis, and underwent EEG in a resting state with closed eyes for 5 min. The asymmetry index (AI) along homologous channel pairs (e.g., F7-8) was assessed using neuronal activity topography (NAT). AI referring to 10 frequency components ranging from 4 to 20 Hz and neuropsychological assessments including linguistic competence were analyzed. Results: The main findings was that the language score had a positive association with AI in 7.8 Hz at F7-8 and a negative association with AI in 6.3 Hz at C3-4 and 14.1 Hz at F3-4. Conclusion: EEG asymmetry in a boundary range might have a special role in linguistic competence, suggesting the application of neural oscillation on the cognitive function evaluation and neurorehabilition induced by a frequency-specific transcranial alternating current stimulation.

[Characteristics of Headache and Neck Pain in Spontaneous Vertebral Artery Dissections].

PURPOSE: Sudden onset severe occipital/nuchal pain is believed to be a typical symptom of vertebral artery dissection(VAD). However, recent developments in diagnostic imaging have suggested that VAD is not always associated with such pain. This study aimed to analyze the clinical features of initial symptoms in patients with VAD. METHODS: In total, this study included 29 consecutive patients who were referred to our hospital because of only headache and/or nuchal pain due to VAD between 2011 and 2016. In this study, their clinical features were precisely assessed, including the pain location, onset pattern, duration, intensity, disease period, diagnosis modality, and prognosis. Both MRI and MRA were performed for all subjects. Cerebral angiography and thin-slice T1-weighted MRI were additionally performed in selected cases. RESULTS: Of the 29 patients, 23 presented with occipital headache and/or nuchal pain. The pain was persistent in 26/29 and ipsilateral in 29/29. However, only 16/29 reported a typical sudden onset. Only 12/29 complained of severe pain, while the other 17/29 presented with dull pain. The mean interval between onset and hospitalization was 7.4 days(0 to 30 days)and the mean interval between hospitalization and diagnosis was 3.9 days(0 to 21 days). Intramural hematoma was identified in 21/29 patients using thin-slice T1-weighted MRI. CONCLUSION: Only 55% of patients with VAD demonstrate typical occipital/nuchal pain with sudden onset. Both MRI and MRA should be indicated for patients who complain of persistent, unilateral pain in the occipital/nuchal regions to prevent VAD being missed during diagnosis.

[Computational Fluid Dynamic Analysis of Intracranial Aneurysms Using Newly Developed Software:Can It Predict the Thin-Walled Region of Intracranial Aneurysm Preoperatively?]

OBJECT: Recent studies have shown that computational fluid dynamics(CFD)analysis is useful to evaluate flow dynamics of intracranial aneurysms. However, CFD analysis still requires high costs and substantial time even now. This study aimed to evaluate whether newly developed software can shorten the time for analysis and serve useful information during clipping surgery for intracranial aneurysms. METHODS: CFD analysis was performed in 55 unruptured cerebral aneurysms in 51 patients. The time required for analysis of each aneurysm was recorded. On the basis of CFD analysis, both pressure and wall shear stress(WSS)were calculated as the values at the systolic and diastolic phases, and also the mean value through one cardiac cycle. These data were compared between thin-wall points and other points within each aneurysm. RESULTS: The average time required for analysis was 3 hours, ranging from 1 to 15 hours. The CFD data could be referenced during surgery in each patient. The pressure in about 93% and 80% of the thin-wall points was higher than that at other points within each aneurysm in the systolic and diastolic phases, respectively. However, there was no significant correlation between WSS and wall thickness in each aneurysm. CONCLUSION: This study clearly shows that newly-developed software is simple and requires much shorter time for CFD analysis than previous methods. Higher pressure through the cardiac cycle may efficiently predict a thin-wall region within intracranial aneurysms, which strongly suggests that CFD analysis would be a valuable tool to determine the treatment strategy in patients with unruptured aneurysms.

Altered Neuronal Activity Topography Markers in the Elderly with Increased Atherosclerosis.

Background: Previously, we reported on vascular cognitive impairment (VCI) templates, consisting of patients with VCI associated with carotid stenosis (>60%) using a quantitative electroencephalographic (EEG) technique called neuronal activity topography (NAT). Here using the VCI templates, we investigated the hypothesis that internal carotid artery-intima-media thickness (ICA-IMT) is associated with EEG spectrum intensity (sNAT) and spectrum steepness (vNAT). Methods: A total of 221 community-dwelling elderly subjects were recruited. Four groups were classified according to quartiles of ICA-IMT as assessed by ultrasonography: control group A, normal (≤0.9 mm); group B, mild atherosclerosis (1-1.1 mm); group C, moderate atherosclerosis (1.2-1.8 mm); and group D, severe atherosclerosis (≥1.9 mm). EEG markers of power ratio index (PRI), and the binary likelihood of being in the VCI group vs. the that of being in control group A (sL x:VCI-A , vL x:VCI-A ) were assessed, respectively. Differences in mean total scores for PRI, sL x:VCI-A , vL x:VCI-A , between control group A and the other groups were compared using Dunnett's test, respectively. Results: The mean total scores of the PRI were 3.25, 3.00, 2.77, and 2.26 for groups A, B, C, and D, respectively. There was a significant decrease in the PRI in group D compared with group A (P = 0.0066). The mean total scores of the sL x:VCI-A were -0.14, -0.11, -0.1, and -0.03 for groups A, B, C, and D, respectively. The sL x:VCI-A in group D was significantly higher compared to that in group A (P < 0.0001). The mean total scores of the vL x:VCI-A were -0.04,-0.01, 0.01, and 0.06 for group A, B, C, and D, respectively. The vL x:VCI-A in group D and group C was significantly higher compared to that in group A, respectively (P < 0.0001, P = 0.02). Conclusion: Community-dwelling elderly subjects in the increased carotid atherosclerosis of ICA-IMT (≥1.9 mm) were at greatest risk of an EEG change as assessed by NAT.

Mobilization of Pluripotent Multilineage-Differentiating Stress-Enduring Cells in Ischemic Stroke.

GOAL: This prospective study was aimed to prove the hypothesis that multilineage-differentiating stress-enduring (Muse) cells are mobilized from bone marrow into peripheral blood in patients with ischemic stroke. MATERIALS AND METHODS: This study included 29 patients with ischemic stroke. To quantify the circulating Muse cells, peripheral blood was obtained from all patients on admission and at days 7 and 30. Using fluorescence-activated cell sorting, Muse cells were identified as stage-specific embryonic antigen-3-positive cells. The control values were obtained from 5 healthy volunteers. Separately, immunohistochemistry was performed to evaluate the distribution of Muse cells in the bone marrow of 8 autopsy cases. FINDINGS: The number of Muse cells robustly increased within 24 hours after the onset, compared with the controls, but their baseline number and temporal profile widely varied among patients. No clinical data predicted the baseline number of Muse cells at the onset. Multivariate analysis revealed that smoking and alcohol intake significantly affect the increase in circulating Muse cells. The odds ratio was .0027 (P = .0336) and 1688 (P = .0220) for smoking and alcohol intake, respectively. The percentage of Muse cells in the bone marrow was .20% ± .17%. CONCLUSION: This study shows that pluripotent Muse cells are mobilized from the bone marrow into peripheral blood in the acute stage of ischemic stroke. Smoking and alcohol intake significantly affect their temporal profile. Therapeutic interventions that increase endogenous Muse cells or exogenous administration of Muse cells may improve functional outcome after ischemic stroke.

Specific Shrinkage of Carotid Forks in Moyamoya Disease: A Novel Key Finding for Diagnosis.

This study was aimed to analyze the outer diameter of the involved arteries in moyamoya disease, using three-dimensional (3D) constructive interference in steady state (CISS) and direct surgical inspection. Radiological evaluation was performed in 64 patients with moyamoya disease. As the controls, six patients with severe middle cerebral artery (MCA) stenosis and 17 healthy subjects were also recruited. On 3D-CISS, the outer diameter was quantified in the supraclinoid portion of internal carotid artery (C1), the horizontal portions of MCA (M1) and anterior cerebral artery (A1), and basilar artery. The involved carotid fork was directly observed during surgery in another series of three adult patients with moyamoya disease. In 53 adult patients with moyamoya disease, the outer diameters of C1, M1, and A1 segments were 2.3 ± 0.7 mm, 1.3 ± 0.5 mm, and 1.0 ± 0.4 mm in the involved side (n = 91), being significantly smaller than the control (n = 17), severe M1 stenosis (n = 6), and non-involved side in moyamoya disease (n = 15, P < 0.01). There were significant correlations between Suzuki's angiographical stage and the outer diameters of C1, M1, and A1 (P < 0.001). The laterality ratio of C1 and M1 was significantly smaller in unilateral moyamoya disease (n = 20) than the controls and severe MCA stenosis (P < 0.01). Direct observations revealed a marked decrease in the outer diameter of the carotid fork (n = 3). These findings strongly suggest specific shrinkage of the involved arteries in moyamoya disease, which may provide essential information to distinguish moyamoya disease from other intracranial arterial stenosis and shed light on the etiology and novel diagnosis cue of moyamoya disease.

Surgical anatomy and preservation of the middle meningeal artery during bypass surgery for moyamoya disease.

BACKGROUND: The middle meningeal artery (MMA) is known to function as one of the important collateral routes in moyamoya disease. However, the anterior branch frequently courses within the lesser wing of the sphenoid bone and can easily be damaged during craniotomy for bypass surgery. This prospective study aimed to study the surgical anatomy of the MMA and to establish the technique to preserve it during bypass surgery for moyamoya disease. METHODS: Twenty-two patients with moyamoya disease underwent STA-MCA anastomosis combined with indirect bypass on 27 sides. The anatomical relationship between the anterior branch of the MMA and lesser wing was classified into three types: the bridge, monorail, and tunnel types. During surgery, the lesser wing was carefully resected with a rongeur or high-speed diamond drill to preserve the anterior branch of the MMA. RESULTS: The anterior branch of the MMA was classified into the bridge type in 5 sides (18.5 %), monorail type in 10 sides (37.0 %), and tunnel type in 12 sides (44.5 %). Patient age was closely related to the anatomical findings (χ (2) test, p = 0.0168). Careful resection of the lesser wing with a rongeur could preserve bridge- and monorail-type MMAs (100 and 71.4 %, respectively). However, drilling out of the lesser wing under a surgical microscope was essential to preserve the tunnel-type MMA. Intraoperative indocyanine green videoangiography was useful to confirm patency during surgery. CONCLUSIONS: It is essential to understand the surgical anatomy of the MMA around the pterion in order to preserve its anterior branch during bypass surgery for moyamoya disease.

Neuronal activity topography parameters as a marker for differentiating vascular cognitive impairment in carotid stenosis.

Previously, we reported on the differentiation between patients with Alzheimer disease and normal controls using a quantitative electroencephalographic technique called neuronal activity topography (NAT). In this technique, cerebral neuronal activities are characterized by the signal intensity and coherence (sNAT and vNAT, respectively). In the present study, we examined 47 patients with vascular cognitive impairment in carotid stenosis and 52 normal controls. All subjects underwent electroencephalography in a resting state with closed eyes for 5 minutes. Electroencephalographic markers of the differential likelihood, that is, the sensitivity-versus-specificity characteristics, sL(x:VCI-NLc) and vL(x:VCI-NLc), were assessed with neuronal activity topography and were compared between the 2 groups. sL(x:VCI-NLc) and vL(x:VCI-NLc) crossed each other at a cutoff value of the differential likelihood. Separation of the patients and controls was made with a sensitivity of 92% and 88%, as well as a false-positive rate of 8% and 12% for sL(x:VCI-NLc) and vL(x:VCI-NLc), respectively. Using sNAT, we accurately differentiated 92% patients with vascular cognitive impairment. We recommend that sNAT, rather than vNAT, should be used in detecting vascular cognitive impaired patients.

An operating microscope with higher magnification and higher resolution for cerebral aneurysm surgery: preliminary experience-technical note.

We describe a higher magnifying power operating microscope system to improve one method of high-quality microsurgical clipping for cerebral aneurysm in some cases. This higher magnification is achieved by a new lens design in the optical system, which makes the image of the object very clear at high magnifications (distinctiveness of 7 µm). This higher-resolution operating microscope system provides the surgeon with higher-magnified images (at the maximum of more than 30× magnifications as each working distance) in the operating field. The magnifications can be changed from low power (2.9×) to high power (62.0×) depending on the circumstances in a given procedure. We have used this operating microscope system on 11 patients with microsurgical clipping for cerebral aneurysms. Microsurgical treatment could be performed safely and precisely. All aneurysms were treated without any technical complications. We think that the use of this microscope would have potential benefits for microsurgical treatment for cerebral aneurysms because of better visualization.

Higher magnification microsurgical repair of donor artery dissection in superficial temporal artery to middle cerebral artery anastomosis--technical note.

Donor artery dissection is a known cause of technical failure in microvascular anastomosis. A method for detection and direct repair of donor artery dissection before superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis is described using a high magnification operating microscope (maximum 50.4× magnification). Before STA-MCA anastomosis, the stump of the STA is stained using methylrosaniline chloride (pyoctaninum blue) and is observed under higher magnifications. Microsurgical suturing of the arterial dissection is performed before the anastomosis procedure under the high magnification microscope. This method was used in two patients with symptomatic hemodynamic cerebrovascular occlusive disease. Postoperative angiography revealed good patency and no complications occurred. This method may be useful for detection and direct repair of arterial dissection in small vessel walls before STA-MCA anastomosis.

"Kissing" aneurysms of the internal carotid artery treated by coil embolization.

A 62-year-old female complaining of sudden severe headache was referred to our stroke center in consultation. Computed tomography showed diffuse spread of thick subarachnoid hemorrhage to the basal cistern and both sylvian fissures, and digital subtraction angiography showed kissing aneurysms arising in the left lateral and occipital directions in the C(1) portion of the internal carotid artery (ICA). The anterior choroidal artery was situated between the two aneurysms, and another small branch originating from the dome of the distal aneurysm was confirmed as a duplicated middle cerebral artery (MCA). Endovascular treatment was successfully performed to spare the two vessels involved. This case of kissing aneurysms and ICA-duplicated MCA is very rare, and presents difficulties for both surgical and endovascular treatments.