[Tonometry yesterday and today].

Instrumental tonometry was developed in the second half of XIX century, especially when local anesthesia of the cornea became available. Imbert-Fick mathematical law and the building, 75 years later, of the excellent Goldmann tonometer were the principal steps of aplanation tonometry; however, this technique is now limited by the difficulties encountered in updating and automatizing the evaluation of aplanated surface. In the other hand, there are some evidence that the ocular tension, as evaluated with Goldmann tonometer, could be different of manometric intraocular pressure in the vitreous cavity, especially when the cornea is abnormal. New tonometers utilizing electric deformimeters technology might be developed particularly to perform continual eye pressure monitoring.