Direct Brachial Approach for Acute Basilar Artery Occlusion: Technical Note and Preliminary Clinical Experience

In mechanical endovascular thrombectomy (MET) for acute basilar artery occlusion (ABAO) in the elderly, navigating a guide catheter via the femoral artery may be difficult due to the approach route’s significant tortuosity. To resolve this problem, we have been performing a technique that uses a direct brachial approach (DiBA) with a large-bore aspiration catheter. We reported our preliminary clinical experience with this technique. MET for ABAO using the DiBA technique was performed on 4 consecutive patients between August 2017 and December 2018. In all patients, thrombolysis in cerebral infarction 2B or 3 recanalization was achieved, but the modified Rankin Scale at 90 days was ≥4. There were no technical difficulties or complications with this technique. The DiBA technique is an effective and feasible approach in MET for ABAO. Although excellent clinical outcomes could not be achieved, the angiographic outcomes were excellent with no technical complications. This approach can be an alternative to the femoral artery approach, particularly for tortuous arteries in the elderly

Bulk motion-independent analyses of water diffusion changes in the brain during the cardiac cycle

金沢大学医薬保健研究域保健学系We evaluated dynamic changes in water diffusion in the brain during the cardiac cycle by using cine diffusion MRI. On a 1.5-T MRI, ECG-triggered single-shot diffusion echo planar imaging was used with sensitivity encoding, halfscan, and rectangular field of view techniques for minimizing bulk motion effects such as brain pulsation, with a data-sampling window of 3 ms. The apparent diffusion coefficient (ADC) and fractional anisotropy (FA) in the white matter zone were determined in ten healthy volunteers and then compared with the intracranial volume change (ICVC) revealed by phase-contrast cine MRI during the cardiac cycle. In addition, a frequency analysis of these waveforms was performed. ADC and FA values changed significantly during the cardiac cycle, despite minimizing the effect of bulk motion, i.e., independent of bulk motion. The ADC was synchronized with the ICVC during the cardiac cycle. A significant positive correlation was noted among their amplitudes. Analysis of the dynamic change of water diffusion by use of cine diffusion MRI facilitates the assessment of intracranial conditions. © 2009 Japanese Society of Radiological Technology and Japan Society of Medical Physics

Secular trends and features of thalamic hemorrhages compared with other hypertensive intracerebral hemorrhages: an 18-year single-center retrospective assessment

IntroductionTrends regarding the locations of hypertensive cerebral hemorrhages are unclear. To clarify hypertensive hemorrhage trends, we investigated intracerebral hemorrhages (ICHs) over an 18-year period, focusing on thalamic hemorrhages compared with other sites of hemorrhages.MethodsWe reviewed the cases of patients hospitalized for hypertensive ICH in 2004–2021 at our hospital; 1,320 eligible patients were registered with a primary ICH/intraventricular hemorrhage. After exclusion criteria were applied, we retrospectively analyzed 1,026 hypertensive ICH cases.ResultsThe proportions of thalamic and subcortical hemorrhages increased over the 18-year period, whereas putaminal hemorrhage decreased. Multivariate logistic regression analyses revealed that for thalamic hemorrhage, ≥200 mmHg systolic blood pressure (p = 0.031), bleeding <15 mL (p = 0.001), and higher modified Rankin scale (mRS) score ≥ 4 at discharge (p = 0.006) were significant variables in the late period (2013–2021) versus the early period (2004–2012), whereas for putaminal hemorrhage, significant factors in the late period were triglyceride <150 mg/dL (p = 0.006) and mRS score ≥ 4 at discharge (p = 0.002). Among the features of the thalamic hemorrhages in the late period revealed by our group comparison with the putaminal and subcortical hemorrhages, the total and subcortical microbleeds were more notable in the thalamic hemorrhages than in the other two types of hemorrhage, whereas cerebellar microbleeds were more prominent when compared only with subcortical hemorrhages.DiscussionOur findings revealed an increasing trend for thalamic hypertensive hemorrhage and a decreasing trend for putaminal hemorrhage. The thalamic hemorrhage increase was observed in both young and older patients, regardless of gender. The main features of thalamic hemorrhage in the late period versus the early period were decrease in larger hemorrhage (≥15 mL) and an increase in cases with higher systolic blood pressure (at least partially involved a small number of untreated hypertensive patients who developed major bleeding). The total and subcortical microbleeds were more notable in the thalamic hemorrhages of the late period than in the putaminal and subcortical hemorrhages. These results may contribute to a better understanding of the recent trends of hypertensive ICHs and may help guide their appropriate treatments for this condition

Frequency analyses of CSF flow on cine MRI in normal pressure hydrocephalus

Abstract Our objective was to clarify intracranial cerebrospinal fluid (CSF) flow dynamics in normalpressure hydrocephalus (NPH). Frequency analyses of CSF flow measured with phase-contrast cine MRI were performed. The CSF flow spectra in the aqueduct were determined in patients (n=51) with NPH, brain atrophy or asymptomatic ventricular dilation (VD), and in healthy volunteers (control group; n=25). The changes in CSF flow spectra were also analyzed after intravenous injection of acetazolamide. Moreover, a phase transfer function (PTF) calculated from the spectra of the driving vascular pulsation and CSF flow in the aqueduct were assessed. These values were compared with the pressure volume response (PVR). The amplitude in the NPH group was significantly larger than that in the VD or control group because of a decrease in compliance. The phase in the NPH group was significantly different from that in either the VD or the control group, but no difference was found between the VD and control groups. The amplitude increased in all groups after acetazolamide injection. The PTF in the NPH group was significantly larger than in the control group, and a positive correlation was noted between PTF and PVR. Frequency analyses of CSF flow measured by cine MRI make it possible to noninvasively obtain a more detailed picture of the pathophysiology of NPH

Japanese nationwide questionnaire survey on delayed cerebral infarction due to vasospasm after subarachnoid hemorrhage

Background and purposeVarious prophylactic drugs for cerebral vasospasm and delayed cerebral infarction (DCI) after subarachnoid hemorrhage (SAH) have been used in Japan. To investigate the treatment trends for cerebral vasospasm and frequency of DCI after SAH throughout Japan in 2021.MethodsIn 2021 we conducted an anonymous questionnaire survey on management for preventing cerebral vasospasm after aneurysmal SAH, and the frequency of DCI. The questionnaire was emailed to 955 certified neurosurgeons at 553 hospitals in Japan. Of them, 162 hospitals (29% response rate) responded to the questionnaire. Of these, 158 were included in this study, while four hospitals that responded insufficiently were excluded. The efficacy of treatments for reducing DCI were examined through a logistic regression analysis.ResultsAmong 3,093 patients treated with aneurysmal SAH, 281 patients (9.1%) were diagnosed with DCI related to cerebral vasospasm. Coil embolization had significantly lower DCI frequency (6.9%), compared to microsurgical clipping (11.8%, odds ratio, 0.90; 95% confidential intervals, 0.84–0.96; P, 0.007). In addition, cilostazol administration was associated with significantly lower DCI frequency (0.48; 0.27–0.82; 0.026). The efficacy of cilostazol in reducing DCI remained unchanged after adjustment for covariates. The most effective combination of multiple prophylactic drugs in reducing DCI related to cerebral vasospasm was cilostazol, fasudil, and statin (0.38; 0.22–0.67; 0.005).ConclusionsThis study elucidated the trends in prophylactic drugs to prevent cerebral vasospasm and frequency of DCI after aneurysmal SAH in Japan. Coil embolization and cilostazol administration showed effectiveness in reducing DCI related to cerebral vasospasm in 2021

Idiopathic Normal-Pressure Hydrocephalus: Temporal Changes in ADC during Cardiac Cycle

Normal-pressure hydrocephalus (NPH) is characterized by a clinical triad of ataxia, incontinence, and dementia, as well as dilated ventricles but normal cerebrospinal fluid (CSF) pressures. In patients with NPH, CSF shunt placement is effective for improving these symptoms (1). NPH has attracted attention as one of the few treatable causes of dementia. Diagnosis of idiopathic NPH (INPH) without a known cause of communicating hydrocephalus, including subarachnoid hemorrhage or meningitis, is particularly difficult (2). Moreover, to clarify the cause of NPH, accurately diagnose NPH, and identify appropriate patients for shunt surgery, several tests have been proposed, including cisternography, the CSF tap test, resistance measures, external lumbar drainage, and intracranial pressure recording, in addition to clinical findings and conventional imaging diagnosis with x-ray computed tomography or magnetic resonance (MR) imaging (3–6). It has also been reported (7) that a single standard for the prognostic evaluation of patients with INPH was lacking and that supplemental tests could increase the predictive accuracy of the prognosis. The CSF tap test is a particularly reliable examination, but it is invasive and has low sensitivity. It has been proposed that MR imaging CSF flow studies can be used to noninvasively obtain information about intracranial mechanical properties in INPH (eg, intracranial compliance) (2,8–12). However, the diagnostic utility of this latter method is still not established.Arterial inflow into the cranium induces venous and CSF outflow and displacement of the intracranial spinal cord during the cardiac cycle, resulting in pulsatile brain motion (12–14). Brain pulsation (ie, bulk motion) reportedly can give rise to artifactual phase dispersion and may lead to overestimation of the apparent diffusion coefficient (ADC) (15,16). Brockstedt et al (17) reported that ADC was not changed significantly during the cardiac cycle with the single-shot echo-planar imaging (EPI) sequence widely used in diffusion MR imaging. However, they analyzed only two delay times (100 and 400 msec) between the R peaks in the cardiac cycle. To more completely analyze ADC changes during the cardiac cycle, our own group has previously evaluated the temporal change in ADC during the entire cardiac cycle by using an electrocardiographically (ECG)-triggered single-shot diffusion EPI sequence to minimize bulk motion effect. As a result, we revealed in a previous study that white matter ADC changed significantly over the cardiac cycle and that such changes were synchronized with the arterial inflow (volume loading) at systole (18). We further hypothesize that changes in ADC during the cardiac cycle are related to the biomechanical properties of intracranial tissues; hence, observed temporal changes in ADC in diseases such as INPH that are characterized by low intracranial compliance (12) may well be different than those in other diseases. Therefore, the purpose of our study was to determine whether temporal changes in ADC over the cardiac cycle were different in patients with INPH as compared with patients with ex vacuo ventricular dilatation and healthy control subjects

Cerebrospinal Fluid Production and Absorption and Ventricular Enlargement Mechanisms in Hydrocephalus

Cerebrospinal fluid (CSF) production and absorption concept significantly changed in the early 2010s from “third circulation theory” and “classical bulk flow theory” to a whole new one as follows: First, CSF is mainly produced from interstitial fluid excreted from the brain parenchyma, and CSF produced from the choroid plexus plays an important role in maintaining brain homeostasis. Second, CSF is not absorbed in the venous sinus via the arachnoid granules, but mainly in the dural lymphatic vessels. Finally, the ventricles and subarachnoid spaces have several compensatory direct CSF pathways at the borders attached to the choroid plexus, e.g., the inferior choroidal point of the choroidal fissure, other than the foramina of Luschka and Magendie. In idiopathic normal pressure hydrocephalus (iNPH), the lateral ventricles and basal cistern are enlarged simultaneously due to the compensatory direct CSF pathways. The average total intracranial CSF volume increased from about 150 mL at 20 years to about 350 mL at 70 years due to the decrease in brain volume with aging and further increased above 400 mL in patients with iNPH. CSF movements are composed of a steady microflow produced by the rhythmic wavy movement of motile cilia on the ventricular surface and dynamic pulsatile flow produced by the brain and cerebral artery pulsation, respiration, and head movement. Pulsatile CSF movements might totally decrease with aging, but it in the ventricles might increase at the foramina of Magendie and Luschka dilation. Aging CSF dynamics are strongly associated with ventricular dilatation in iNPH

RELIABILITY AND VALIDITY OF THE DIGIT CANCELLATION TEST, A BRIEF SCREEN OF ATTENTION

The reliability and validity of a screening test called the D-CAT (Digit Cancellation Test) were evaluated across two studies. The D-CAT was developed to provide a highly practical and user-friendly assessment of various aspects of prefrontal cortex functioning, including information processing speed, the ability to focus attention, and executive functioning. Participants perform the D-CAT by deleting given target numbers on a sheet of randomly arranged possibilities. In Study 1, the reliability of the D-CAT was evaluated using a test-retest paradigm. Reasonably high correlations between scores on the two test sessions were obtained. In Study 2, construct validity was examined using a sample of participants with traumatic brain injury. TBI participants showed significantly lower D-CAT performance than age and education level matched healthy controls. On the basis of these findings, the D-CAT can be regarded as a reliable and valid screening test for attentional functioning. Key words: screening test for attention, digit cancellation test, traumatic brain injury, test-reliability, test-validity "Higher-order cognitive functioning" consists of several different facets, including attention, memory, language, and problem solving. Each of the facets interrelates with the others in complex ways, although attention is regarded as a basic aspect of executive function in so-called higher-order cognitive functioning. The assessment of attention can be regarded as one of the most important basic aspects of any neuropsychological evaluation. Various assessments of human attentional abilities have been developed, including the Paced Serial Addition Test (PASAT), Brief Test of Attention (BTA)