The CLASSICAL Barkan goniotomy procedure is widely used and accepted as the treatment of choice for most cases of congenital glaucoma. In the classical technique, illumination is provided by a hammer light held near the surgeon's head by an assistant who directs it onto the eye along the line of vision of the surgeon.1-3 If the operation is properly performed, the percentage of success with one or multiple operations is good, but, in practice, the procedure can be exceedingly difficult. One of the most important difficulties encountered is inadequate visualization of the chamber angle during the goniotomy due to problems associated with the illumination system.
Reflections from external surfaces can significantly impair the surgeon's view. These reflections arise from the goniotomy lens, the cornea, the knife handle, the knife blade, and from the surgeon's gloved hand. In addition, as the knife is inserted into the eye, the smooth corneal
Amoils SP, Simmons RJ. Goniotomy With Intraocular IlluminationA Preliminary Report. Arch Ophthalmol. 1968;80(4):488-491. doi:10.1001/archopht.1968.00980050490015