Primary Retinal Detachment

Some Basics of Surgical Technique 103
fold at the posterior edge of a horseshoe tear is a radial buckle. A
radial buckle supports the operculum and, at the same time, closes
the posterior edge of the break, avoiding fishmouthing [23]. Goldbaum
et al. [24] calculated that when applying a circumferential
buckle, radial folds are less likely if the buckle is not longer than
90° (Fig. 6.3). If the circumferential buckle is less than 90°, the induced
radial folds, caused by constriction of the globe, will be compensated
by the sloping ends of the buckle.
The radial buckle is advantageous because it: (1) places the entire
break on the ridge of the buckle; (2) counteracts fishmouthing
of the break and the risk of posterior leakage; and (3) provides optimal
support for the operculum, counteracting future traction and
the risk of anterior leakage. Therefore, whenever possible, the
sponge should be oriented with its long axis in a radial direction of
the break. Multiple radial buckles can be used if the breaks are separated
by approximately 1 1 / 2 clock hours. When a circumferential
buckle is necessary, the greater the length of the buckle, the more
likely radial folds will result. Consequently, the shorter the circumferential
buckle, the better it is.
Thus, minimal segmental buckling or so-called extraocular
minimal surgery had evolved [25, 26]. It is one of the four options
today in use for treating a primary rhegmatogenous retinal detachment.
Some Basics of Surgical Technique
This surgery, performed under local anesthesia, is suitable for primary
retinal detachments caused by one or several breaks. It consists
of cryosurgery under ophthalmoscopic control and a sponge,
preferably radially oriented, to the break. Consequently, the size of
the buckle is determined only by the size of the break(s) and not by
the extent of the detachment. The treatment of the two detachments,
presented in Fig. 6.1, is the same and consists of a sponge
buckle of equal size. After an analysis of 1,000 detachments, we