Comparison of pre-mortem 2D-3D ultrasound examination to post-mortem micro-CT of carotid arteries - first experiences.

Background and purpose:

A prerequisite for the treatment of carotid atherosclerosis is the accurate measurement of the stenosis, that is most commonly evaluated by duplex ultrasonography. In this study, we aimed to verify the reliability of 2D and 3D ultrasonography, comparing the data to results of post-mortem micro-CT examination.

Neurological patients with any life-threatening, presumably fatal neurological disease were enrolled. Ultrasound examinations were performed with a Philips Epiq 5G machine, using a VL13-5 broadband linear volume array transducer. Plaque length, diameter and vessel area reduction (stenosis) were calculated using the 2D images. Finally, the stenosis was reassessed using automatized, 3D application as well. After the death of the patient, autopsy was performed, during which the previously examined carotid artery was removed. The samples were examined with micro-CT. Similar to the ultrasound examination, plaque length, diameter and vessel area reduction (stenosis) were determined.

Ten vessels of seven patients were eligible for complex comparison. Plaque diameter and length measured by CT did not correlate with the ultrasound data. CT-measured axial plaque and vessel areas showed no correlation with ultrasound results either. While determining the strength of correlation between stenoses measured by the different modalities, significant correlation was found between the results measured by ultrasound (2D) and CT (Pearson r: 0.902, P<0.001).

Three-dimensional ultrasound analysis is a spectacular method for examining carotid plaques, as it can assist in a more detailed evaluation of the plaque morphology and composition, thereby identifying plaques with a particularly high risk of stroke. Micro-CT is an excellent tool for the exact determination of calcified plaque areas, but ultrasound images are not suitable yet for such a precise examination due to acoustic shadowing and artifacts.

Role of carotid duplex in the assessment of carotid artery restenosis after endarterectomy or stenting.

Introduction: Redo carotid endarterectomy (CEA) and carotid stenting (CAS) are often performed when there is evidence of post-procedural restenosis. The incidence of restenosis after carotid reconstruction is not negligible, ranging from 5 to 33%. The diagnosis of significant internal carotid artery (ICA) restenosis is usually based on duplex ultrasound (US) criteria, mostly on peak-systolic flow velocity (PSV). However, there have been no generally accepted duplex US criteria for carotid restenosis after CAS or CEA. Methods: In this systematic review, the PubMed/ Medline and Scopus databases were screened to find trials that reported duplex US criteria for significant restenosis after CEA and/or CAS. Only those reports were analyzed in which the restenoses were also assessed by CT/MR or digital subtraction angiography as comparators for duplex US. Results: Fourteen studies met the predetermined search criteria and were included in this review. In most studies, PSV thresholds for significant in-stent ICA restenosis after CAS were higher than those for significant stenosis in non-procedurally treated (native) ICA. Many fewer studies investigated the US criteria for ICA restenosis after CEA. Despite the heterogeneous data, there is a consensus to use higher flow velocity thresholds for assessment of stenosis in stented ICA than in native ICA; however, there have been insufficient data about the flow velocity criteria for significant restenosis after CEA. Although the flow velocity thresholds for restenosis after CAS and CEA seem to be different, the large studies used the same duplex criteria to define restenosis after the two procedures. Moreover, different studies used different flow velocity thresholds to define ICA restenosis, leading to variable restenosis rates. Discussion: We conclude that (1) further examinations are warranted to determine appropriate duplex US criteria for restenosis after CAS and CEA, (2) single duplex US parameter cannot be used to reliably determine the degree of ICA restenosis, (3) inappropriate US criteria used in large studies may have led to false restenosis rates, and (4) studies are required to determine if there is a benefit from redo carotid artery procedure, such as redo-CEA or redo-CAS, starting with prospective risk stratification studies using current best practice non-invasive care alone.

Structural health monitoring of sabo check dams with cosmic-ray muography.

Debris dams have a crucial role in consolidation of river basins and allow erosion control, flood protection in mountainous areas. Many of these infrastructures have operated over five decades, thus structural health monitoring (SHM) of these infrastructures became timely due to their aging. Utilizing new techniques is required for inspecting a large number of dams and deciding about their reinforcement or reconstruction. In this work, we propose cosmic-ray muography as a complementary tool for the SHM of debris dams. We conducted the first muographic surveying of a sabo check dam in the Karasu River, Gunma, Japan. The average mass density image was produced with a spatial resolution of 0.5 m through the dam. The comparison of density data reconstructed by muography and gamma-ray logging suggest the internal deterioration of dam in the region where cement released out from the embankment body.

Hemorrhagic Transformation of Ischemic Strokes.

Ischemic stroke, resulting from insufficient blood supply to the brain, is among the leading causes of death and disability worldwide. A potentially severe complication of the disease itself or its treatment aiming to restore optimal blood flow is hemorrhagic transformation (HT) increasing morbidity and mortality. Detailed summaries can be found in the literature on the pathophysiological background of hemorrhagic transformation, the potential clinical risk factors increasing its chance, and the different biomarkers expected to help in its prediction and clinical outcome. Clinicopathological studies also contribute to the improvement in our knowledge of hemorrhagic transformation. We summarized the clinical risk factors of the hemorrhagic transformation of ischemic strokes in terms of risk reduction and collected the most promising biomarkers in the field. Also, auxiliary treatment options in reperfusion therapies have been reviewed and collected. We highlighted that the optimal timing of revascularization treatment for carefully selected patients and the individualized management of underlying diseases and comorbidities are pivotal. Another important conclusion is that a more intense clinical follow-up including serial cranial CTs for selected patients can be recommended, as clinicopathological investigations have shown HT to be much more common than clinically suspected.

Elevated Blood Alcohol Concentration Is Associated with Improved Clinical Outcomes of Intravenous Thrombolysis Treatment in Acute Ischemic Stroke Patients-A Retrospective Study.

BACKGROUND: Intravenous thrombolysis (IVT) improves acute ischemic stroke (AIS) outcomes, but with limited success. In addition, ethanol potentiates the effect of r-tPA in ischemia models. METHODS: The effect of acute alcohol consumption on IVT outcomes was investigated in a retrospective cohort study. AIS patients with detectable blood alcohol concentration (BAC) during IVT were included (alcohol group; n = 60). For each case, 3 control subjects who underwent IVT but denied alcohol consumption were matched in terms of age, sex, affected brain area, and stroke severity. Outcomes were determined using the NIHSS at 7 days and the modified Rankin scale (mRS) at 90 days. RESULTS: Patients were younger and had a less severe stroke than in a standard stroke study. Favorable long-term outcomes (mRS 0-2) occurred significantly more frequently in the alcohol group compared to controls (90% vs. 63%, p < 0.001). However, the rates of hemorrhagic transformation were similar. Multiple logistic regression models identified elevated BAC as a significant protective factor against unfavorable short-term (OR: 0.091, 95% CI: 0.036-0.227, p < 0.001) and long-term outcomes (OR: 0.187, 95% CI: 0.066-0.535, p = 0.002). In patients with BAC > 0.2%, significantly lower NIHSS was observed at 3 and 7 days after IVT vs. in those with 0.01-0.2% ethanol levels. CONCLUSION: Elevated BAC is associated with improved outcomes in IVT-treated AIS without affecting safety.

Potential benefits of intraoperative ultrasound in neurosurgery.

Computed tomography and magnetic resonance imaging are the most popular diagnostic tools to visualize intracranial pathology and help surgical planning in the neurosurgical practice. However, these preoperative techniques need to be supplemented with intraoperative methods, if the lesion size may increase or preoperative anatomy may change after the primary imaging due to rapid progression of the underlying intracranial disease. In such situations intraoperative ultrasound could be a valuable technique in real-time imaging of intracranial pathologic processes, real-time control of surgical procedure, assistance in drain or catheter placement, and real-time assessment of residual tumor or hematoma volume during neurosurgical interventions.

Atmospheric muography for imaging and monitoring tropic cyclones.

Large-scale solid bodies on Earth such as volcanoes and man-made pyramids have been visualized with solid earth muography, and the recently invented technique, acqueous muography, has already demonstrated its capability to visualize ocean tides and tsunami. In this work, atmospheric muography, a technique to visualize and monitor the vertical profile of tropic cyclones (TCs) is presented for the first time. The density distribution and time-dependent behavior of several TCs which had approached Kagoshima, Japan, has been investigated with muography. The resultant time-sequential images captured their warm cores, and their movements were consistent with the TC trails and barometric pressure variations observed at meteorological stations. By combining multidirectional muographic images with barometric data, we anticipate that muography will become a useful tool to monitor the three-dimensional density distribution of a targeted mesoscale convective system.

Low α2-Plasmin Inhibitor Antigen Levels on Admission Are Associated With More Severe Stroke and Unfavorable Outcomes in Acute Ischemic Stroke Patients Treated With Intravenous Thrombolysis.

Background: Intravenous administration of recombinant tissue plasminogen activator (rt-PA) fails to succeed in a subset of acute ischemic stroke (AIS) patients, while in approximately 6-8% of cases intracerebral hemorrhage (ICH) occurs as side effect. Objective: Here, we aimed to investigate α2-plasmin inhibitor (α2-PI) levels during thrombolysis and to find out whether they predict therapy outcomes in AIS patients. Patients/Methods: In this prospective, observational study, blood samples of 421 AIS patients, all undergoing i.v. thrombolysis by rt-PA within 4.5 h of their symptom onset, were taken before and 24 h after thrombolysis. In a subset of patients (n = 131), blood was also obtained immediately post-lysis. α2-PI activity and antigen levels were measured by chromogenic assay and an in-house ELISA detecting all forms of α2-PI. α2-PI Arg6Trp polymorphism was identified in all patients. Stroke severity was determined by NIHSS on admission and day 7. Therapy-associated ICH was classified according to ECASSII. Long-term outcomes were defined at 3 months post-event by the modified Rankin Scale (mRS). Results: Median α2-PI activity and antigen levels showed a significant drop immediately post-lysis and increased to subnormal levels at 24 h post-event. Admission α2-PI levels showed a significant negative stepwise association with stroke severity. Patients with favorable long-term outcomes (mRS 0-1) had significantly higher admission α2-PI antigen levels (median:61.6 [IQR:55.9-70.5] mg/L) as compared to patients with poor outcomes (mRS 2-5: median:59.7 [IQR:54.5-69.1] and mRS 6: median:56.0 [IQR:48.5-61.0] mg/L, p < 0.001). In a Kaplan-Meier survival analysis, patients with an α2-PI antigen in the highest quartile on admission showed significantly better long-term survival as compared to those with α2-PI antigen in the lowest quartile (HR: 4.54; 95%CI:1.92-10.8, p < 0.001); however, in a multivariate analysis, a low admission α2-PI antigen did not prove to be an independent risk factor of poor long-term outcomes. In patients with therapy-related ICH (n = 34), admission α2-PI antigen levels were significantly, but only marginally, lower as compared to those without hemorrhage. Conclusions: Low α2-PI antigen levels on admission were associated with more severe strokes and poor long-term outcomes in this cohort. Our results suggest that in case of more severe strokes, α2-PI may be involved in the limited efficacy of rt-PA thrombolysis.

Periodic sea-level oscillation in Tokyo Bay detected with the Tokyo-Bay seafloor hyper-kilometric submarine deep detector (TS-HKMSDD).

Meteorological-tsunami-like (or meteotsunami-like) periodic oscillation was muographically detected with the Tokyo-Bay Seafloor Hyper-Kilometric Submarine Deep Detector (TS-HKMSDD) deployed in the underwater highway called the Trans-Tokyo Bay Expressway or Tokyo Bay Aqua-Line (TBAL). It was detected right after the arrival of the 2021 Typhoon-16 that passed through the region 400 km south of the bay. The measured oscillation period and decay time were respectively 3 h and 10 h. These measurements were found to be consistent with previous tide gauge measurements. Meteotsunamis are known to take place in bays and lakes, and the temporal and spatial characteristics of meteotsunamis are similar to seismic tsunamis. However, their generation and propagation mechanisms are not well understood. The current result indicates that a combination of muography and trans-bay or trans-lake underwater tunnels will offer an additional tool to measure meteotsunamis at locations where tide gauges are unavailable.

Discrepancies between clinical and autopsy findings in patients who had an acute stroke.

OBJECTIVES: According to international observations, the incidence of clinical autopsies is declining worldwide, plummeting below 5% in the USA and many European countries. It is an unfavourable trend as, in 7%-12% of cases, recent clinicopathological studies found discrepancies that might have changed the therapy or the outcome if known premortem. As previous large-scale observations have examined varied patient populations, we aimed to focus on the differences between the clinical and pathological diagnostic findings in only patients who had a stroke. MATERIAL AND METHODS: We assessed the postmortem non-neuropathological and neuropathological findings of 534 consecutive patients who had a stroke who passed away. Systemic neoplasms, pneumonias, thromboembolisms and haemorrhagic transformations revealed only by autopsy were considered severe abnormalities; in addition, benign abnormalities important from an educational or scientific point of view were also recorded. RESULTS: In 26 of the 534 cases (4.9%), the presence of systemic neoplasms had already been confirmed in the clinical stage; however, 8 (1.5%) malignant tumours were only detected during autopsy. Also, 80 (15%) thromboembolic events, 73 (13.6%) pneumonias and 66 (18%) haemorrhagic transformations were only diagnosed at autopsy. Longer hospital stay (from admission to death) resulted in fewer discrepancies between clinical and autopsy diagnosis of thromboembolic events and pneumonias (p<0.01). In 169 cases, benign findings were detected. CONCLUSIONS: While the type of acute stroke is reliably diagnosed with imaging techniques, postmortem autopsies are also important in patients who had a stroke as autopsies may reveal clinically silent diseases (eg, tumour), and contribute to knowing the actual incidence of stroke-related thromboembolic and pneumonia complications.

Effects of acute alcohol consumption on neuronal activity and cerebral vasomotor response.

INTRODUCTION: In the majority of European countries, driving after drinking small-moderate amount of alcohol is legal. Motivated by our previous studies on cerebral hemodynamics, we aimed to study whether a small-moderate blood alcohol content (BAC), at which driving is legal in some countries (0.8 g/L), influences the neuronal activity, neurovascular coupling, and cerebral vasoreactivity. METHODS: Analyses of pattern-reversal visual evoked potential (VEP) and transcranial Doppler (TCD) examinations were performed in thirty young healthy adults before and 30 min after alcohol consumption. Cerebral vasoreactivity was evaluated by breath holding test in both middle cerebral arteries. By using a visual cortex stimulation paradigm, visually evoked flow velocity response during reading was measured in both posterior cerebral arteries (PCA). RESULTS: The BAC was 0.82 g/L and 0.94 g/L 30 and 60 min after drinking alcohol, respectively. Latency of the VEP P100 wave increased after alcohol consumption. Resting absolute flow velocity values increased, whereas pulsatility indices in the PCA decreased after alcohol ingestion, indicating vasodilation of cerebral microvessels. Breath holding index and the visually evoked maximum relative flow velocity increase in the PCA and steepness of rise of the flow velocity curve were smaller after than before alcohol consumption. CONCLUSION: BAC close to a legal value at which driving is allowed in some European countries inhibited the neuronal activity and resulted in dilation of cerebral arterioles. Cerebral vasodilation may explain the decrease of cerebral vasoreactivity and might contribute to the disturbance of visually evoked flow response after alcohol consumption.

First results of undersea muography with the Tokyo-Bay Seafloor Hyper-Kilometric Submarine Deep Detector.

Tidal measurements are of great significance since they may provide us with essential data to apply towards protection of coastal communities and sea traffic. Currently, tide gauge stations and laser altimetry are commonly used for these measurements. On the other hand, muography sensors can be located underneath the seafloor inside an undersea tunnel where electric and telecommunication infrastructures are more readily available. In this work, the world's first under-seafloor particle detector array called the Tokyo-bay Seafloor Hyper-Kilometric Submarine Deep Detector (TS-HKMSDD) was deployed underneath the Tokyo-Bay seafloor for conducting submarine muography. The resultant 80-day consecutive time-sequential muographic data were converted to the tidal levels based on the parameters determined from the first-day astronomical tide height (ATH) data. The standard deviation between ATH and muographic results for the rest of a 79-day measurement period was 12.85 cm. We anticipate that if the length of the TS-HKMSDD is extended from 100 m to a full-scale as large as 9.6 km to provide continuous tidal information along the tunnel, this muography application will become an established standard, demonstrating its effectiveness as practical tide monitor for this heavy traffic waterway in Tokyo and in other important sea traffic areas worldwide.

Muographic monitoring of hydrogeomorphic changes induced by post-eruptive lahars and erosion of Sakurajima volcano.

Post-eruptive destabilization of volcanic edifices by gravity driven debris flows or erosion can catastrophically impact the landscapes, economies and human societies surrounding active volcanoes. In this work, we propose cosmic-ray muon imaging (muography) as a tool for the remote monitoring of hydrogeomorphic responses to volcano landscape disturbances. We conducted the muographic monitoring of Sakurajima volcano, Kyushu, Japan and measured continuous post-eruptive activity with over 30 lahars per year. The sensitive surface area of the Multi-Wire-Proportional-Chamber-based Muography Observation System was upgraded to 7.67 m[Formula: see text]; this made it possible for the density of tephra within the crater region to be measured in 40 days. We observed the muon flux decrease from 10 to 40% through the different regions of the crater from September 2019 to October 2020 due to the continuous deposition of tephra fallouts. In spite of the long-term mass increase, significant mass decreases were also observed after the onsets of rain-triggered lahars that induced the erosion of sedimented tephra. The first muographic observation of these post-eruptive phenomena demonstrate that this passive imaging technique has the potential to contribute to the assessment of indirect volcanic hazards.

Decreased clot burden is associated with factor XIII Val34Leu polymorphism and better functional outcomes in acute ischemic stroke patients treated with intravenous thrombolysis.

BACKGROUND: Intravenous thrombolysis using recombinant tissue plasminogen activator remains the mainstay treatment of acute ischemic stroke (AIS), although endovascular treatment is becoming standard of care in case of large vessel occlusions (LVO). To quantify the thrombus burden in LVO, a semiquantitative CT angiography (CTA) grading system, the clot burden score (CBS) can be used. Here we aimed to study the association between CBS and various hemostasis parameters, and to evaluate which parameters are major determinants of thrombolysis outcome. METHODS: In this single-centered prospective observational case-control study, 200 anterior circulation AIS patients receiving intravenous thrombolysis treatment without thrombectomy were enrolled: 100 AIS patients with LVO (CBS 0-9) and 100 age- and sex-matched AIS patients without LVO (CBS 10). Fibrinogen, α2-plasmin inhibitor, plasminogen, factor XIII and D-dimer were assessed from blood samples taken before and 24 h after thrombolysis, and FXIII-A Val34Leu was genotyped. CBS was calculated using admission CTA. Short-term outcomes were defined based on the change in NIHSS by day 7, long-term outcomes were assessed according to the modified Rankin scale at 3 months post-event. RESULTS: Poor outcomes were significantly more frequent in the CBS 0-9 group. Plasminogen activity on admission was significantly higher in the CBS 0-9 group. In a univariate analysis, significant protective effect of the Leu34 allele against developing larger clots (CBS 0-9) could be demonstrated (OR:0.519; 95%CI:0.298-0.922, p = 0.0227). Multivariate regression analysis revealed that CBS is an independent predictor of short- and long-term functional outcomes, while such effect of the studied hemostasis parameters could not be demonstrated. CONCLUSIONS: CBS was found to be a significant independent predictor of thrombolysis outcomes. FXIII-A Leu34 carrier status was associated with smaller thrombus burden, which is consistent with the in vitro described whole blood clot mass reducing effects of the allele, but the polymorphism had no effect on thrombolysis outcomes.

The applications of transcranial Doppler in ischemic stroke.

BACKGROUND: This overview provides a summary of the applications of transcranial Doppler (TCD) in ischemic stroke. RESULTS: A fast-track neurovascular ultrasound protocol has been developed for detecting occlusion or stenosis. The technique is more reliable in the carotid area than in the posterior circulation. By monitoring the pulsatility index the in-crea-sed intracranial pressure can be diagnosed. TIBI score was developed for grading residual flow. TCD has been shown to accurately predict complete or any recanalization. Regarding recanalization, TCD has a sensitivity of 92%, a specificity of 88%, a positive predictive value of 96%, a negative predictive value of 78% and an overall accuracy of 91%, respectively. Sonothrombolysis seemed to be a promising application but randomized controlled trials have shown that it does not improve clinical outcome. TCD examination can detect microembolic signals (MES) which are associated with an increased risk of stroke. Micro-em-boli were detected in symptomatic and asymptomatic carotid artery stenosis and during carotid endarterectomy. The number of microemboli can be decreased by antithrombotic therapy. Contrast en-chan-ced examination and Valsalva maneuver with continuous TCD monitoring can accurately screen for right-to-left shunt.

Hypertension-induced subclinical vascular and cognitive changes are reversible-An observational cohort study.

Beside the well-known complications of poorly controlled, long-standing hypertension, milder abnormalities induced by early-stage hypertension have also been described. In our study, the authors examined the reversibility of changes induced by early-stage hypertension. The authors performed laboratory testing, ambulatory blood pressure monitoring, carotid intima-media thickness (IMT) measurement, evaluation of stiffness parameters, assessment of various cardiac and cerebral hemodynamic parameters during head-up tilt table (HUTT) testing, and neuropsychological examinations in 49 recently diagnosed hypertensive patients. Following baseline assessment, antihypertensive therapy was commenced. After one year of therapy, lower IMT values were found. Pulse wave velocity showed a borderline significant decrease. During HUTT, several hemodynamic parameters improved. The patients performed better on neuropsychological testing and reached significantly lower scores on questionnaires evaluating anxiety. The present study shows that early vascular changes and altered cognitive function observed in newly diagnosed hypertensive patients may improve with promptly initiated antihypertensive management.

Effect of reading with direct or indirect light on the visually evoked flow response in the posterior cerebral artery.

PURPOSE: Reading with direct light from computer monitors or tablets may cause visual fatigue and hamper reading comprehension. Our aim was to compare the blood flow response in the supplying artery of the visual cortex when reading from tablet screen or from paper. The neurovascular coupling was tested also after 15-minute reading from either monitor or paper. METHODS: Flow velocity responses evoked by reading from paper and from monitor were measured by transcranial Doppler sonography in a random sequence in both posterior cerebral arteries (PCAs) of 20 young healthy adults. Afterward, PCA flow response evoked by reading from paper was also investigated after 15 minutes reading on the same tablet or paper, in a random order. RESULTS: Reading from monitor with its own source of light and reading from paper with indirect light caused very similar PCA flow response. Moreover, the flow velocity increase, evoked by reading form paper did not differ after 15-minute reading from monitor or from paper. CONCLUSIONS: Reading with direct or indirect light produces similar flow response in the occipital cortex.

Acute alcohol intoxication may cause delay in stroke treatment - case reports.

BACKGROUND: The signs and symptoms of acute alcohol intoxication resemble those of vertebrobasilar stroke. Due to their shared symptoms including double vision, nystagmus, dysarthria, and ataxia, the differential diagnosis of alcohol intoxication and vertebrobasilar stroke may pose a challenge. Moreover, if alcohol intoxication and stroke occur simultaneously, the signs and symptoms of stroke may be attributed to the effects of alcohol, leading to delayed stroke diagnosis and failure to perform reperfusion therapy. CASE PRESENTATIONS: Three cases of alcohol intoxication and stroke are presented. The first patient (female, 50 years old) had dysarthria, nystagmus and trunk ataxia on admission. Her blood alcohol level was 2.3‰. The symptoms improved after forced diuresis, but 5.5 h later progression was observed, and the patient developed diplopia and dysphagia in addition to her initial symptoms. Angiography showed occlusion of the basilar artery. Intraarterial thrombolysis was performed. The second patient (male, 62 years old) developed diplopia, dysarthria and trunk ataxia after consuming 4-units of alcohol, and his symptoms were attributed to alcohol intoxication. Two hours later, neurological examination revealed dysphagia and mild right-sided hemiparesis, which questioned the causal relationship between the symptoms and alcohol consumption. Cerebral CT was negative, and intravenous thrombolysis was administered. The third patient (male, 55 years old) consumed 10 units of alcohol before falling asleep. Three hours later, his relatives tried to wake him up. He was unresponsive, which was attributed to alcohol intoxication. When he woke up 8 h later, right-sided hemiparesis and aphasia were observed, and cerebral CT already revealed irreversible ischemic changes. CONCLUSIONS: Our cases show that alcohol consumption may interfere with stroke diagnosis by mimicking the signs and symptoms of vertebrobasilar stroke. Moreover, attributing the symptoms of stroke to alcohol intoxication may delay stroke diagnosis resulting in failure of reperfusion therapy. Based on our observations we conclude that stroke should be considered in the case of worsening symptoms, dysphagia, hemiparesis and disproportionately severe signs that cannot be attributed to the amount of alcohol consumed. In the case of ambiguity, ambulance should be called, and if stroke cannot be excluded, specific therapy should be administered.