Physicians, Plagues and Progress: The History of Western Medicine From Antiquity to Antibiotics by Chapman Allan

Author:Chapman, Allan
Language: eng
Format: epub
Publisher: Lion Hudson UK
Published: 2016-04-07T04:00:00+00:00

THOMAS WILLIS AND HIS “CIRCLE”

Over the late 1650s, much of Willis’s attention seems to have been focused upon laboratory research, although he was constantly expanding his clinical expertise as an increasingly successful (and wealthy) practising physician. This had laid the foundation for his work on fevers and fermentation in the Diatribae of 1658–59, which were to win him fame across Europe. By the early 1660s, however, and now holding the prestigious Sedleian Professorship of Natural Philosophy [Natural Science] in Oxford University, with which he had been presented at the Restoration in 1660, Willis was turning his attention to the blood supply to and the nervous appendages of the human brain.

The brain was a mysterious organ, especially when seen in relation to its complex nervous appendages which ran – like Harvey’s cardiovascular physiology – to every part and extremity of every living body. The brain’s physiological chemistry too appeared a puzzle in 1660. Why, for example did the heart drive warm blood up the carotid and vertebral arteries into the head, and the jugular and other veins return it to the heart, while the cortex itself in dissection seemed cold and largely bloodless? How did some of this blood transform into the watery “animal spirit” (cerebrospinal fluid) found in the brain ventricles of dissected cadavers? All of that was dwarfed by the huge mystery of how the brain enabled us to perceive, respond, think, and imagine.

An incident took place sometime before 1664, which Willis described in his Cerebri Anatome (“Anatomy of the Brain”) of that year, which would turn out to be transformative in our scientific understanding of the brain. Willis was dissecting the cadaver of a man whom he appears to have known in life, when he was struck by the presence of a long-standing blockage of the right carotid artery in his neck. The carotid had become osseam (“bony”) or lapideam (“stony”) hard and long since incapable of conveying blood.7 Yet the right vertebral artery, which runs close by the carotid, had swollen two or three times in size, as though to compensate for the failed carotid.

By traditional physiological reasoning, the man should have been either dead long since or should have manifested signs of major brain-function impairment, such as an “apoplexy” or stroke, for the right hemisphere of his brain would not have been receiving its full and necessary blood supply. This is what Galen’s anatomy taught: when blood passed up the carotids, it entered the rete mirabile or “wonderful network” of vessels, half of which nourished the left brain hemisphere and half the right, and even the swollen right vertebral artery would have left part of the brain blood-deficient. But as Willis made clear, the man had displayed no signs of brain dysfunction and had died from a stomach problem: a large schirrus[scirrhous] or hard, ulcerated tumour of the abdominal mesentery – a cancerous tumour, most likely, though it was probably not recognized as such in the early 1660s.8

It was this problem of the failed carotid which

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.