Performing an examination

The contact lens dynamometer, whose sensor attachment is connected to an electronic plotter by a narrow cable, is placed onto the eyeball in the same way as the conventional three-mirror lens after instillation of local anaesthesia. Contact lens pressure is then increased continually in the direction of the sagittal axis of the eye, until diastolic blood pressure is exceeded and the first pulsations of the central retinal artery or its branches become visible on the optic disk. Diastolic central arterial pressure is defined as the lowest intraocular pressure at which the first pulsations of the central artery can be observed. It is at this time exactly that the pressure continuously displayed on the LCD screen is recorded and noted by activating a foot switch or a key. Systolic blood pressure can be measured in the same way. When systolic blood pressure is exceeded the central artery collapses. Systolic central arterial pressure is defined as the lowest intraocular pressure at which the artery remains collap.

Because the Goldmann contact lens makes an excellent examination of the fundus possible it is not necessary as a rule to use drops to dilatate the pupils for dynamometry.