Diathermy and scleral shortening operations are both effective for the cure of retinal detachments. The principle of sealing the hole and draining the subretinal fluid to allow reattachment of the retina can be accomplished by either procedure. As a matter of fact, both operations have a very similar effect on the eye: namely, shortening of the sclera, reduction of the volume of the eye, and closure of the retinal hole with diathermy.
When a retinal detachment is treated by means of nonperforating intrascleral diathermy, a choroidal scar is produced that will close the retinal hole and create a firm chorioretinal adhesion sufficiently strong to permanently reattach the retina. In the course of treatment there is marked shrinkage of the sclera of the entire treated area. This shrinkage not only shortens the sclera but reduces the volume of the vitreous cavity (Figs. 1 and 2). Both structural changes are desirable in
WADSWORTH JAC. Diathermy or Scleral Resection. AMA Arch Ophthalmol. 1958;60(2):258-262. doi:10.1001/archopht.1958.00940080274014