[Biomicroscopy of the fundus oculi using a 90 diopter lens]

An improved method of indirect biomicroscopic examination of the ocular fundus has been made possible with the use of a + 90 D lens since 1985. Its special optical characteristics make it a very useful instrument. During this study of 220 retinal detachments we compared this instrument with other methods for examining the ocular fundus (Goldmann fundus contact lens, panfundoscope, binocular indirect ophthalmoscope with a 20 D lens). Other uses for the lens are described. This non-contact examining technique provides excellent visualisation, a wide field of vision, and good patient tolerance. The 90 D lens is particularly useful in vitreo-retinal management of retinal detachment both during and immediately after surgery.