[Modifications of the pupil in acute subdural hematoma]

This study is based on the observation of 81 operated acute subdural haematoma. The various coordinates concerning the clinical aspects and the evolution are analysed in function of the presence or absence of pre-operatory anisoria. The discussion abords the gravity of this sign and its value in localizing the lesion, as well as the clinical distinction between ipsi-lateral and contra-lateral mydriasis. Possible subdivisions in cases of contra-lateral relative mydriasis, as well as their probable pathophysiological mechanisms and respective clinical and prognostic implications are also examined.