Willis, Thomas


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Willis, Thomas

(wil′is)
Brit. anatomist, 1621–1675.
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CIRCLE OF WILLIS: Inferior view of brain

circle of Willis

An arterial anastomosis that encircles the optic chiasm and hypophysis, from which the principal arteries supplying the brain are derived. It receives blood from the two internal carotid arteries and the basilar artery formed by union of the two vertebral arteries. See: illustration

Willis cord

One of the cords crossing the superior longitudinal sinus transversely.

Willis pancreas

An obsolete term for the lesser pancreas.

Willis,

Thomas, English physician, 1621-1675.
accessorius willisii - nerve that arises by two sets of roots: cranial, emerging from the side of the medulla, and spinal, emerging from the ventrolateral part of the first five cervical segments of the spinal cord. Synonym(s): accessory nerve
chordae willisii - Synonym(s): Willis cords
circle of Willis - an anastomotic circle of arteries at the base of the brain. Synonym(s): arterial circle of cerebrum
Willis centrum nervosum - the largest and highest group of prevertebral sympathetic ganglia, located on the superior part of the abdominal aorta. Synonym(s): celiac ganglia
Willis cords - several fibrous cords crossing the superior sagittal sinus. Synonym(s): chordae willisii
Willis pancreas - a portion of the head of the pancreas formed by the superior mesenteric artery and abdominal aorta. Synonym(s): uncinate process of pancreas
Willis paracusis - the apparent increase in auditory acuity of a deaf person to conversation in noisy surroundings due to a companion's unconscious voice raising. Synonym(s): false paracusis
Willis pouch - obsolete term for lesser omentum.