Akira Imai

Three-dimensional mapping of local cerebral perfusion in alcoholic encephalopathy with and without Wernicke-Korsakoff syndrome

Seventeen severe chronic alcoholic patients with and without Wernicke-Korsakoff syndrome (WKS) were examined prospectively after being treated by withdrawal from alcohol. The WKS patients also received thiamine supplements. Three-dimensional measurements of local cerebral blood flow (LCBF) and local partition coefficients (LΛ) were made utilizing xenon contrast computed tomography (Xe CT-CBF). Results were displayed as color-coded brain maps before and after treatment and these were correlated with neurological and cognitive examinations. Before treatment chronic alcoholics without WKS (n = 10) showed diffuse reductions of LCBF values throughout all gray matter including hypothalamus, vicinity of nucleus basalis of Meynert, thalamus, and basal ganglia. Similar, but more severe, reductions were seen in patients with WKS (n = 7), however, white matter perfusion was also reduced. In WKS, most prominent reductions of LCBF were also seen in hypothalamus and basal forebrain nuclei but thalamus, basal ganglia, and limbic systems were severely reduced. After treatment, both groups with alcoholic encephalopathy showed marked clinical improvement and cerebral perfusion was restored toward normal. Chronic alcohol abuse, in the absence of thiamine deficiency, reduces CBF by direct neurotoxic effects. If thiamine deficiency is also present, more severe and localized hemodynamic reductions are superimposed.

Headache, cardiac arrest, and intracranial hemorrhage

Headache is one of the most common manifestations of non-traumatic intracranial hemorrhage, which is an uncommon, but not rare, cause of cardiac arrest in adults. History of a sudden headache preceding collapse may be a helpful clue to estimate the cause of out-of-hospital cardiac arrest (OHCA). Medical records of witnessed OHCA patients were reviewed to identify those who complained of a sudden headache preceding collapse, and the incidence of intracranial hemorrhage among them as well as their clinical characteristics was investigated retrospectively. During the 12-month period, 124 patients who sustained a witnessed OHCA were treated. Among them, 74 (60%) collapsed without any pain complaint, and only 6 (5%) complained of a sudden headache preceding collapse. All of the six patients were resuscitated: four had a severe subarachnoid hemorrhage (SAH), while the other two had a massive cerebellar hemorrhage. By contrast, 39 of the 74 patients who collapsed without any pain were resuscitated. Among them, another six patients were found to harbor an SAH. Thus, a total of 12 among the 124 witnessed OHCA (10%) sustained a fatal intracranial hemorrhage. While OHCA patients who collapse complaining of a sudden headache are uncommonly seen in the emergency room, they have a high likelihood of harboring a severe intracranial hemorrhage. It should also be reminded that approximately half of patients whose cardiac arrest is due to an intracranial hemorrhage may collapse without complaining of a headache. The prognosis of those with cerebral origin of OHCA is invariably poor, although they may relatively easily be resuscitated temporarily. Focus needs to be directed to avoid sudden death from a potentially treatable cerebral lesion, and public education to promote the awareness for the symptoms of potentially lethal hemorrhagic stroke is warranted.

Stroke while driving: Frequency and association with automobile accidents:

Background Cardiovascular events while driving have occasionally been reported. In contrast, there have been few studies on stroke while driving. Aim The objectives of this study were to (1) report the frequency of stroke while driving and (2) evaluate its association with automobile accidents. Methods Clinical data prospectively acquired between January 2011 and December 2016 on 2145 stroke patients (1301 with ischemic stroke, 585 with intracerebral hemorrhage, and 259 with subarachnoid hemorrhage) were reviewed to identify patients who sustained a stroke while driving. The ratio of driving to performing other activities was evaluated for each stroke type. Furthermore, the drivers’ response to stroke was reviewed to understand how automobile accidents occurred. Results Among the 2145 patients, 85 (63 ischemic stroke, 20 intracerebral hemorrhage, and 2 subarachnoid hemorrhage) sustained a stroke while driving. The ratio of driving to performing other activities was significantly higher in ischemic stroke (4.8%) than in intracerebral hemorrhage (3.4%) or subarachnoid hemorrhage (0.8%). A majority of drivers either continued driving or pulled over to the roadside after suffering a stroke. However, 14 (16%) patients were involved in automobile accidents. In most patients, an altered mental status due to severe stroke was the presumed cause of the accident. Conclusion Stroke occurred while driving in 4.0% of all strokes and accidents occurred in 16% of these instances.

Clinical Characteristics of Stroke Occurring while Bathing

BACKGROUND Stroke can occur during any human activity. Although cardiac arrests or drowning accidents while bathing have been studied extensively, there are few studies focusing on stroke occurring while bathing. The objectives of this study were to evaluate the clinical characteristics of stroke occurring while bathing and the association between stroke and drowning accidents. METHODS Clinical data prospectively acquired between January 2011 and December 2015 on 1939 patients with stroke (1224 cerebral infarctions [CIs], 505 intracerebral hemorrhages [ICHs], and 210 subarachnoid hemorrhages [SAHs]) were reviewed to identify patients who sustained a stroke while bathing. The ratio of bathing-related strokes to strokes occurring during other activities was evaluated. Moreover, the demographics of these 2 groups were compared in each stroke type. RESULTS Among the 1939 patients, 78 (CI, 32; ICH, 28; and SAH, 18) sustained a stroke while bathing. The ratio of bathing to other activities in the SAH group was the highest (8.6%), followed by the ICH group (5.5%), whereas that in the CI group was the lowest (2.6%). Regardless of stroke type, only a minority of patients were found to have collapsed inside the bathtub. CONCLUSIONS The higher ratio of bathing in hemorrhagic strokes may indicate that there is a small risk of hemorrhagic stroke while bathing in vulnerable subjects. This retrospective study did not establish a causal relationship between bathing and stroke nor identify risk factors, which means that future prospective studies are warranted. The finding that the great majority of bathing-related stroke patients were found to have collapsed outside the bathtub suggests that the involvement of stroke in drowning accidents in the bathtub may be small.