The pneumotonograph was evaluated for its capability to record and measure intraocular pressure through soft contact lenses. In a series of patients with chronic corneal diseases treated with soft contact lenses, good pressure and intraocular pulsations were recorded both with and without the soft lenses. Areas of scarred cornea give incorrect values, whereas areas of corneal edema give values similar to those obtained in the presence of a soft lens and are believed to reflect accurate and reliable pressure readings. In normal eyes, it has been found that the presence of a plain soft lens does not modify the accuracy of pressure measurement. High values do occur, however, when the refraction of the lens exceeds eight diopters.