Teppei Komatsu

Olfactory function combined with morphology distinguishes Parkinson's disease

OBJECTIVE This study aimed to examine whether the volume of the olfactory bulbs and tracts (OB & T) on magnetic resonance imaging (MRI) is useful for differentiating Parkinsons disease (PD) from PD-related disorders. METHODS The study group comprised 13 patients with PD, 11 with multiple system atrophy (MSA), five with progressive supranuclear palsy, and five with corticobasal degeneration (PSP/CBD). All patients were evaluated using the odor stick identification test for Japanese (OSIT-J), (123)I-meta-iodobenzylguanidine (MIBG) scintigraphy, and brain MRI. OB & T areas on 1-mm-thick coronal images were measured and summed for volumes. We examined relationships between olfactory function and volume, and cardiovascular dysautonomia. We defined the cut-off values for OSIT-J score or MIBG uptake and OB & T volume to discriminate PD from PD-related disorders and calculated the proportional rate of PD in four categorized groups. RESULTS OB & T volume was smaller in PD than in MSA or PSP/CBD (p < 0.05 each). The cut-off for detecting PD patients was OSIT-J score <8, heart/mediastinum ratio <1.6, and OB & T volume <270 mm(3). In the group with OSIT-J score <8 and OB & T volume <270 mm(3), the proportion of PD patients among all patients with PD-related disorders was 91%. The rate of probable PD gradually increased as OSIT-J score and OB & T volume decreased (p < 0.001). CONCLUSIONS Although preliminary, these data obtained from a combined morphological and functional evaluation of OB or cardiovascular dysautonomia could be useful for further differential of PD and other PD-related disorders.

Relationship between Vertebral Artery Hypoplasia and Posterior Circulation Ischemia.

PURPOSE Vertebral artery hypoplasia (VAH) is a common congenital anatomical variation. In previous reports, it was unclear whether VAH was an independent risk factor for posterior circulation ischemia. The purpose of this study was to evaluate the impact of VAH on posterior circulation ischemia. METHODS Subjects were patients with acute ischemic stroke who underwent brain magnetic resonance imaging (MRI) and carotid ultrasonography. Diagnostic criteria for VAH were as follows: (1) Vertebral artery (VA) diameter less than 2.5 mm; (2) VA diameter less than 3.0 mm and a difference in length equal to or greater than 1:1.7; (3) VA diameter less than 3.0 mm, peak systolic velocity less than 40 cm/second, and resistance index value greater than .75. The patients were categorized by the location of the ischemic stroke on MRI as follows: lesion in posterior circulation (P group), lesion in anterior circulation (A group), and multiple lesions in both the anterior and posterior circulations (AP group). RESULTS We evaluated 129 consecutive patients. VAH was seen in 39, and VA occlusion was found in 15. The prevalence of VAH in the P group (44.4%) was significantly higher than that in the A + AP group (24.7%, P = .034). Multivariate regression analysis showed that large-artery atherosclerosis (odds ratio, 6.3; 95% confidence interval [CI], 1.3-30.1), posterior circulation ischemia (odds ratio, 12.0; 95% CI, 2.8-51.2), and VAH (odds ratio, 4.2; 95% CI, 1.2-15.0) were independent factors related to VA occlusion. CONCLUSION VAH was an independent factor related to VA occlusion. Therefore, VAH likely plays a role in posterior circulation ischemia.

An uncovered risk factor of sonothrombolysis: Substantial fluctuation of ultrasound transmittance through the human skull

&NA; Sonothrombolysis is one of the most feasible methods for enhancing clot lysis with a recombinant tissue plasminogen activator (rt‐PA) in cases of acute ischemic strokes. For safe and efficient clinical practices of sonothrombolysis, accurate estimation of ultrasound transmittance through the human skull is critical. Previously, we reported substantial and periodic fluctuation of ultrasound transmittance through a bone‐phantom plate following changes to ultrasound frequency, the thickness of the bone‐phantom plate, and the distance between a transducer and the bone‐phantom plate. In the present study, we clarify the transmittance behavior of medium‐frequency ultrasound (from 400 kHz to 600 kHz) through the human skull, and examine reduction of the transmittance fluctuation. For the study, we measured transmittance of sinusoidal ultrasound waves at 400 kHz, 500 kHz, and 600 kHz at 13 temple spots on 3 human skulls by changing the distance between a transducer and the skull bone, and found substantial and periodic fluctuation in the transmittance behaviors for these sinusoidal voltage excitations. Degrees of the fluctuation varied depending on the measurement spots. A fluctuation ratio between the maximum transmittance and the minimum transmittance reached 3 in some spots. This large transmittance fluctuation is considered to be a risk factor for sonothrombolysis therapies. We examined a modulated ultrasound wave to reduce the fluctuation, and succeeded in obtaining considerable reduction. The average fluctuation ratios for 400‐kHz, 500‐kHz, and 600‐kHz waves were 2.38, 2.38, and 2.07, respectively. We successfully reduced the ratio to 1.72 by using a periodic selection of random frequency (PSRF)‐type of modulation wave. The thus obtained results indicate that attention to the fluctuation in ultrasound transmittance through the skull is necessary for safe and effective sonothrombolysis therapies, and that modulated ultrasound waves constitute a powerful method for reducing the risk of fluctuation. HighlightsWe measured ultrasound transmittance through the human skull for several frequencies around 500 kHz.We found substantial and periodic fluctuation in the ultrasound transmittance.This fluctuation significantly declined with the use of modulated ultrasound.

Transcranial Color Flow Imaging Can Evaluate the Severity of Periventricular Hyperintensity

BACKGROUND The goal of this study was to investigate the relationship between white matter lesions on magnetic resonance imaging and flow parameters in the middle cerebral artery (MCA) measured by transcranial color flow imaging. METHODS Patients with acute ischemic stroke or transient ischemic attack were included. The relationship between severities of periventricular hyperintensity (PVH) and ultrasonographic parameters in the MCA was investigated. The frequency of PVH was calculated for different categories according to the presence or absence of 2 considerable parameters according to the value of area under the receiver operating characteristic curve. RESULTS MCA flow was successfully measured in 203 temporal windows among 124 patients. After determining the cutoff value of end-diastolic velocity (EDV) and pulsatility index (PI) for the presence of PVH, 4 different categories were established: Category A, EDV more than 40 cm/second and PI less than .7; Category B, EDV more than 40 cm/second and PI more than .7; Category C, EDV less than 40 cm/second and PI less than .7; and Category D, EDV less than 40 cm/second and PI more than .7. The prevalence of PVH gradually increased along with category (P < .01). CONCLUSIONS The evaluation of MCA parameters using the combination of PI and EDV may be useful for the prediction of PVH.

Clinical Characteristics of Intracranial Reversed Vertebral Artery Flow Evaluated by Transcranial Color Flow Imaging

BACKGROUND Carotid duplex ultrasonography (CUS) has been used to identify reversed vertebral artery flow (RVAF) at the extracranial cervical artery in some patients with subclavian steal syndrome. However, the characteristics of intracranial RVAF as evaluated by transcranial color flow imaging (TC-CFI), which can examine intracranial hemodynamics in a real-time and noninvasive fashion, remain unclear. The goal of this study was to analyze the prevalence of intracranial RVAF and its associated clinical characteristics. METHODS Subjects were consecutive patients who underwent TC-CFI and CUS. We evaluated blood flow in both intracranial vertebral arteries (VAs) from the suboccipital echo window using TC-CFI. RVAF was defined as a flow signal directed toward the probe. We calculated the prevalence of intracranial RVAF in our subjects. Then, we investigated vascular condition (ie, site of lesion, stenosis, occlusion, and dissection) using magnetic resonance angiography, computed tomography angiography , and CUS in patients with intracranial RVAF. RESULTS Seven hundred twenty patients (508 men; median age, 73 years) were included in this study from September 2007 to March 2013. Intracranial RVAF was seen in 12 patients (1.7%; 11 men; median age, 61 years). Among the 12 patients with intracranial RVAF, 8 patients (67%) had ischemia of the vertebrobasilar territory with distal VA occlusion, according to CUS. Of those patients, 6 (75%) had dissection of the VA. CONCLUSIONS TC-CFI detected intracranial RVAF in 1.7% of consecutive examinations in our facility. In vertebrobasilar territory stroke patients with intracranial RVAF, VA dissection may contribute to the development of stroke.

A novel probe attached to the neck can accurately detect a large patent foramen ovale

PURPOSE We developed a novel probe (pastable soft ultrasound probe; PSUP) attached to the neck for right-to-left shunt (RLS) detection. The purpose of this study was to evaluate the diagnostic ability of the PSUP for RLS detection by comparison with transesophageal echocardiography (TEE). METHODS The subjects were patients with ischemic strokes and transient ischemic attacks who underwent TEE. Based on TEE, patients with patent foramen ovale (PFO) were divided into two groups by the number of microbubbles (MBs): small PFO (1-29 MBs) and large PFO (≥30 MBs). Then, PSUP examination of one common carotid artery (CCA) was started using a procedure similar to TEE. RLS was diagnosed by PSUP when one or more microembolic signals were found in the CCA. The detection rate by size of PFO was compared between TEE and PSUP, and the diagnostic accuracy of PSUP was calculated. RESULTS From May 2014 to July 2016, 84 patients (63 males, median age 63 years) were included; 41 (49%) were diagnosed with PFO by TEE, while PSUP detected PFO in 31 (37%). Using TEE findings as the reference, PSUP for PFO showed sensitivity of 68%, specificity of 93%, and accuracy of 81%. On TEE, 22 patients had large PFOs, and 19 patients had small PFOs. The PSUP could identify large PFOs in grade I and II of International Consensus Criteria more accurately than small ones (58 and 86% vs. 29 and 14%, P = 0.003). CONCLUSIONS The PSUP has considerable accuracy for diagnosing large PFOs. PSUP should play an important role in detecting large PFOs.

The NAG scale: Noble Predictive Scale for Hematoma Expansion in Intracerebral Hemorrhage

BACKGROUND AND PURPOSE Early hematoma expansion (HE) is not rare in intracerebral hemorrhage (ICH) patients, but detecting those patients with high risk of HE is challenging. The aim of this retrospective study was to investigate the factors associated with HE in acute ICH patients, and to develop a simple predictive scale for HE. METHODS We retrospectively reviewed consecutive patients with primary ICH, who received an initial non-contrast computed tomography (CT) scan within 24 hours from symptom onset. Patients underwent follow-up CT scans at 6 hours, 24 hours, and 7 days after admission. We compared the clinical characteristics of patients with and without HE (defined as an increase in intracerebral hemorrhage volume >33% or an absolute increase >6 mL on follow-up CT scans), and performed a logistic regression analysis to determine the predictors of HE. RESULTS A total of 118 patients (78 men; median age 63 years; interquartile range 54-73) were included in our study. HE was observed in 30 patients (25%). HE patients showed higher rates of anticoagulant use (20% vs. 2%, respectively; P=0.003), high National Institutes of Health Stroke Scale on admission (13 vs. 7, respectively; P=0.001), and high plasma glucose (141 mg/dl vs. 113 mg/dl, respectively; P=0.001) compared with patients without HE. After multivariate logistic regression analysis, we selected three factors for defining the NAG scale (1 point as baseline National Institutes of Health Stroke Scale ≥10, 1 point as anticoagulant use, and 1 point as plasma glucose ≥133 mg/dL). The frequencies of HE associated with the NAG scale scores were as follows: score 0, 4%; score 1, 25%; score 2, 60%; score 3, 100%. CONCLUSION Stroke severity, hyperglycemia, and anticoagulation use were factors independently associated with HE. The NAG scale consists of readily available factors and can predict HE.

Perivascular enhancement in anti-MOG antibody demyelinating disease of the CNS

A 47-year-old man had a fever of 39℃, weight loss and night sweat 4 months before admission. Two months later he presented with diplopia, and developed gait disturbance another month later. He was admitted because of disturbed consciousness with a Mini-Mental State Examination score of 24. Brain MRI with fluid-attenuated inversion recovery findings on admission showed bilateral asymmetric high intensity with partial mild swelling on white matter, corpus callosum, cerebellum and brainstem (figure 1A, B). Enhanced MRI detected punctate and curvilinear enhancement suggestive of perivascular infiltration and nodular enhancement (figure 1C, D). A cerebrospinal fluid analysis showed a cell count of 11 cells/µL (mononuclear cells: 94%), an elevated protein level (101 mg/dL). The oligoclonal bands were negative. IgG index was 0.5. Figure 1 MRI of the brain obtained and biopsy specimen before treatment. …

Transcranial color-coded sonography of vertebral artery for diagnosis of right-to-left shunts

BACKGROUND It is unknown whether contrast transcranial color-coded sonography of vertebral artery monitoring via the foramen magnum window (cTCCS-VA) is useful to detect right-to-left shunt (RLS). We investigated whether cTCCS-VA can be proposed as an alternative to middle cerebral artery monitoring via the temporal bone window (cTCCS-MCA) for RLS detection, as compared with contrast transesophageal echocardiography (cTEE). METHODS We evaluated 112 patients with ischemic stroke or transient ischemic attack. We compared the sufficiency of both acoustic windows in each age tertile. Then, we analyzed the accuracy of cTCCS in diagnosing an RLS for a patent foramen ovale (PFO) detected by cTEE. RESULTS In the higher-age tertile, the foramen magnum window was significantly more sufficient than the temporal bone window (100% vs. 71%, p<0.001). In 94 patients having both windows, diagnosis of an RLS using cTCCS-MCA revealed a specificity of 42%, and a sensitivity of 84%. Diagnosis of an RLS using cTCCS-VA revealed a specificity of 40%, and a sensitivity of 91%. Analysis of the subgroup with large PFOs revealed a specificity of 71% using both cTCCS-MCA and cTCCS-VA. CONCLUSIONS cTCCS-VA should play an important role in detecting an RLS, especially in elderly stroke patients having large PFOs.

Venous Stasis and Cerebrovascular Complications in Cerebral Venous Sinus Thrombosis

Background/Aims: The factors related to cerebrovascular complications in cerebral venous sinus thrombosis (CVST) are controversial. We focused on venous stasis and investigated its relationship with cerebrovascular complications in CVST. Methods: CVST patients between June 2013 and October 2016 were enrolled. Relationships between cerebrovascular complications, defined as cerebral venous infarction, intracerebral hemorrhage, or subarachnoid hemorrhage, and cerebrum venous stasis and other clinical information were retrospectively analyzed. Venous stasis was evaluated by the prominence of the veins on susceptibility-weighted imaging (SWI). The cerebrum was divided into 10 regions according to the venous drainage territories, and venous stasis was quantified by adding one point for venous prominence on SWI for each region (CVST SWI score). Results: All 5 cases in the noncomplicated group had a CVST SWI score of 0. The 3 patients with CVST SWI scores higher than 0 had cerebrovascular complications. The CVST SWI scores were higher in the complicated group than in the noncomplicated group (3.0 vs. 0, p = 0.010). Seizures were seen in all patients with complications and in none of the patients without complications (3 vs. 0, p = 0.018). Conclusion: Venous stasis evaluated by SWI can help predict cerebrovascular complications in CVST. A seizure is an important initial symptom that suggests cerebrovascular complications in CVST.