Facts versus theories: an everlasting struggle. The Johann Jakob Wepfer Award 2010.

Rather than a complete overview of the contribution of Utrecht to stroke research, I have selected a few subjects and attempt to put these in historical context. Johann Jakob Wepfer (1620-1695) was unique in that he approached 'apoplexy' through post-mortem observations, in the tradition of Padua. However, the interpretation of his findings in haemorrhagic and especially non-haemorrhagic stroke was still heavily influenced by the authority of Galen's writings. Wepfer's category of 'serous apoplexy' assumed that extravasation of blood serum might lead to compression of brain substance and blockage of 'nerve pores' through which mental 'spirit' was supposed to flow. This notion of 'cerebral congestion' or 'cerebral hyperaemia' lived on, at least to the middle of the 20th century! The pitfalls of theorizing are also evident from recent history (the facile assumption that cerebral ischaemia occurs in the same way as leg ischaemia). By implication, similar errors may well be hidden in present ideas about stroke. Probable or possible examples are the idées reçues that 30 mg of aspirin is less efficacious in the secondary prevention of stroke than 100 mg, that vasospasm is the cause of delayed ischaemia after aneurysmal subarachnoid haemorrhage and that perimesencephalic haemorrhage is not caused by rupture of an artery. Physicians still speculate more often than they care to admit.