Introduction: Byzantium continued Greek and Roman habit of texts compilation, and so, preserved medical knowledge. In addition, assimilating the influence of Monastic and Arabic medicine, Byzantine physicians transmitted original contributions including references to neurological diseases. Alexander of Tralles was one of major exponents of Byzantine medicine. He received his early medical training with his father, and in extensive travels, gathered medical knowledge and experience.
Aim: Medici libri duodecim is a treatise on pathology and therapeutics of internal diseases, in twelve books. It comprises views from observation of different diseases. Its influence was prolonged and it was translated and edited until Renaissance. We analyze grecolatin edition by Henricum Petrum (1556), with special interest in neurological disease citations. DEVELOPMENT. First of twelve books is dedicated to head and brain diseases. When considering headache, he classifies them, following Aretaeus of Cappadocia, in cephalalgia, cephalea and hemicrania, suggesting different pathogenic mechanisms and therapies. Headache is included among symptoms conducting, as well as memory or sleep disturbances, to delirium. Medici libri duodecim considers memory complaints among systemic diseases, mainly with cardiac involvement. Alexander distinguishes between paralysis (privation of sensibility and mobility concerning half of the body), and apoplexy (including main soul functions loss, even conducting to death). Regarding epilepsy, Medici libri duodecim considers that its origin can be outside the head, mainly in the stomach, and offers us descriptions of epileptic auras.
Conclusion: Analysis of Alexander of Tralles' Medici libri duodecim shows how byzantine physicians understood neurological diseases. Therapeutics was based on venesection, medicinal plants and avoidance of noxious substances.