![]() ![]() ![]() The patient reported feeling slightly dizzy and having mild difficulty walking but denied headache, paresthesia, muscle weakness, or recent trauma. She recalled going to bed at 1 am, having no symptoms at the time. History of present illness and past medical historyĪ 65-year-old woman presented to the emergency department complaining of double vision: she had woken up at 8 am and noticed the problem right away but waited until noon that day to seek medical care. In everyday practice, observing any one of these in its classical form is an infrequent occurrence this makes necessary the use of diagnostic procedures, such as MRI, whenever the precise localization of the lesion is desired, with the downside that they can be prohibitively time-consuming. A number of stroke syndromes have been described, in an attempt to correlate sets of clinical findings with the involvement of a specific artery or anatomical region. Due to the close proximity of nuclei to white matter tracts in the brainstem and to the diversity of functions these structures serve, the clinical presentation of posterior circulation strokes is all but consistent. In some individuals, a part of this territory is instead supplied by the anterior system, owing to anatomic variants. The territory supplied by the posterior circulation extends rostrally from the spinal cord along the three embryonic divisions of the brain, including the hindbrain (pons, cerebellum, and medulla), midbrain, and parts of the forebrain (occipital lobes, splenium of the corpus callosum, and thalamus). The proportion of global cerebral blood flow supplied by the posterior circulation is similar, with around one-fourth coming from the vertebrobasilar system, as assessed from Doppler ultrasound and magnetic resonance imaging (MRI) modalities. Posterior circulation strokes account for around a fifth of all strokes. ![]()
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