ABSTRACT
Cerebral microbleeds (CMB) are a common MRI finding, representing underlying cerebral microhemorrhages (CMH). The etiology of CMB and microhemorrhages is obscure. We conducted a pathological investigation of CMH, combining standard and immunohistological analyses of postmortem human brains. We analyzed 5 brain regions (middle frontal gyrus, occipital pole, rostral cingulate cortex, caudal cingulate cortex, and basal ganglia) of 76 brain bank subjects (mean age ± SE 90 ± 1.4 years). Prussian blue positivity, used as an index of CMH, was subjected to quantitative analysis for all 5 brain regions. Brains from the top and bottom quartiles (n = 19 each) were compared for quantitative immunohistological findings of smooth muscle actin, claudin-5, and fibrinogen, and for Sclerosis Index (SI) (a measure of arteriolar remodeling). Brains in the top quartile (i.e. with most extensive CMH) had significantly higher SI in the 5 brain regions combined (0.379 ± 0.007 vs 0.355 ± 0.008; p < 0.05). These findings indicate significant coexistence of arteriolar remodeling with CMH. While these findings provide clues to mechanisms of microhemorrhage development, further studies of experimental neuropathology are needed to determine causal relationships.
Subject(s)
Cerebral Hemorrhage/pathology , Aged, 80 and over , Autopsy , Female , Humans , Male , Retrospective StudiesABSTRACT
Isolated pontine infarcts are common and are often associated with well-described syndromes that are classified based on their specific clinical presentation and arterial stroke territories. Here we present a case of acute combined diplopia and unilateral lower extremity sensory abnormality. Diffusion-weighted magnetic resonance imaging revealed a punctate area of acute ischemia in the right medial pontine mid-tegmentum. These findings suggest a unique pontine stroke syndrome characterized by acute ischemic injury at the intersection of the medial lemniscus and cranial nerve VI.
Subject(s)
Abducens Nerve Diseases/etiology , Brain Stem Infarctions/complications , Diplopia/etiology , Lower Extremity/innervation , Pontine Tegmentum/blood supply , Sensation Disorders/etiology , Abducens Nerve Diseases/diagnosis , Abducens Nerve Diseases/physiopathology , Brain Stem Infarctions/diagnostic imaging , Brain Stem Infarctions/physiopathology , Diffusion Magnetic Resonance Imaging , Diplopia/diagnosis , Diplopia/physiopathology , Female , Humans , Middle Aged , Pontine Tegmentum/diagnostic imaging , Predictive Value of Tests , Sensation Disorders/diagnosis , Sensation Disorders/physiopathology , SyndromeABSTRACT
Limb shaking is a rare manifestation of transient ischemic attacks (TIA) associated with carotid occlusion, mostly unilateral events. We describe the case of a 69 year-old man who presented with repeated episodes of irregular jerking movements in the bilateral upper and lower extremities, precipitated by standing up. Cerebral angiograms revealed occlusion of both internal carotid arteries, and the patient's symptoms responded to targeted blood pressure management. Physicians should be mindful of bilateral limb-shaking TIA when presented with bilateral paroxysmal events that can mimic seizures or orthostatic hyperkinesia.
Subject(s)
Carotid Artery, Internal , Carotid Stenosis/complications , Dyskinesias/etiology , Ischemic Attack, Transient/etiology , Lower Extremity/innervation , Upper Extremity/innervation , Aged , Antihypertensive Agents/adverse effects , Blood Pressure/drug effects , Carotid Artery, Internal/diagnostic imaging , Carotid Artery, Internal/physiopathology , Carotid Stenosis/diagnostic imaging , Carotid Stenosis/physiopathology , Cerebrovascular Circulation/drug effects , Dyskinesias/diagnosis , Dyskinesias/physiopathology , Humans , Ischemic Attack, Transient/diagnostic imaging , Ischemic Attack, Transient/physiopathology , Male , Risk Factors , Treatment OutcomeABSTRACT
Bihemispheric ischemic strokes secondary to unilateral vessel disease are uncommon. We present the case of a 70-year-old man with multiple acute/subacute bilateral infarcts. The patient was found to have stenosis of the left internal carotid artery secondary to herpes zoster ophthalmicus vasculopathy, with involvement of the left proximal middle and anterior cerebral arteries. Angiographic studies also revealed A1 segment aplasia of the right anterior cerebral artery (ACA), thus indicating dependence on the left-sided circulation for perfusion of the bilateral ACA vascular territory. This case illustrates how A1 segment aplasia, an anatomic variant of the circle of Willis detected by angiographic studies, can contribute to bilateral infarction in the ACA vascular territory.
