IT is necessary to check the supposed projection of a retinal rupture, or tear, on the surface of the sclera during the operation. This is done either with pupillary or with scleral transillumination. In using the latter method, I found Goldmann's1 instrument very satisfactory.
It consists of a small metal cover with tiny, sharp teeth, which, with a rotating movement, fix the cover to the sclera. Subsequently, a very small electric lamp is inserted in it. The light of this little lamp is completely masked by the metal cover, except for the beam passing through a small hole in the flat surface of the metal cover, adjacent to the sclera wall, which can be detected ophthalmoscopically.
The relative position of the spot of light of the transilluminator and the rupture indicate the error in localization, which with this method can easily be estimated and corrected.
Though this method proved