Baron Larrey at the Dawn of Correlative Neuroanatomy

In 1820, a young soldier was accidentally injured by a splinter of a fencing sword that penetrated through the right orbit into the brain. Examination by the French military surgeon Baron D.-J. Larrey revealed nominal aphasia, right hemiplegia, and monocular temporal hemianopia with an altitudinal component in the right eye only. In this paper, we aimed to reconstruct Larrey's contribution to neurology in the eve of correlative neuroanatomy. Larrey predicted that the blade passed from the roof of the right orbit to graze the root of the right optic nerve at the chiasm and from there, into the vicinity of the left Sylvian fissure. This course was verified posthumously 3 months later. Larrey's previous experience with galvanic currents enabled the adoption of Samuel von Sömmering's idea of regarding the brain as a telegraphing system made of a multitude of galvanic piles sending and receiving messages from distant points. Larrey's description is a very early diligent study of the tracks of penetrating head injuries. It correlates the symptoms with the injured cerebral tissues together with autopsy verification. Here are the beginnings of the construction of human correlative neuroanatomy, which lingered until flourishing in the first decades of the 20th century.