ONE OF the problems in the treatment of retinal tears by the application of cyrocongelation is the precise localization of the freezing relative to the hole. Often the freezing does not appear in the center of the mound produced by indentation of the cryoprobe. This is due to the oblique application of the tip of the probe or pressure by the probe shaft on the surface of the eye. Visualization of the probe contact area can also be a problem in cases of bullous retinal detachments.
In order to overcome these problems, a transilluminated retinal cryoprobe was devised. It is constructed in such a manner that the actual point of the probe casts a circular shadow in the center of a round patch of light.
One thousand, clad, optical fibers (0.002 inch thick) were inserted in two hemispherical molds and embedded in epoxy resin. The distal end of the
Amoils SP. A Transilluminating Retinal Cryoprobe. Arch Ophthalmol. 1968;80(3):371. doi:10.1001/archopht.1968.00980050373016