12 Limits of External Buckling in Treating Complicated Retinal Detachments In this Chapter the limits of segmental buckling will be discussed and the indication for an alternative operation, either the gas operation or vitrectomy with gas, will be presented. These holes are limited to a circumscribed area at the posterior pole and comprise 1% to maximal 2% of retinal breaks in a consecutive series of detachments (see Chapter 10.6.3, pp. 221–232). Buckling of posteriorly located holes harbors a greater morbidity than tamponading them by an intraocular gas bubble. In this situation a gas tamponade may be the method of choice; a primary vitrectomy is not needed. Breaks at different latitude can be treated with external buckling. However, the issue of its limits can arise when one buckle is interfering with the other or the breaks at different latitude exceed the extent of a scleral pouch (see Part 1, Chapters 8.8.2–8.8.6, pp. 181–190). Therefore, the buckles have to be placed precisely and should not be larger than required to reduce the risk of buckles interfering with each other or the morbidity of large or very posterior buckles. As a consequence, skillful indirect ophthalmoscopy and precise localization of the detached breaks are mandatory. The extraocular procedure has a minimum of complications [1]. The alternative procedures, such as an intraocular gas bubble (pneumatic retinopexy) or a gas bubble combined with prior vitrectomy, have a higher morbidity. As will be discussed in the next Chapter (see Chapter 13, pp. 299–308) there is a greater risk of PVR, i.e., 4% [2] to 6.1% after gas or 11.5% after vitrectomy, and a greater need for reoperations, i.e., 19% [2] to 26% after gas or 24.5% after vitrectomy. For tears with an extent between 70° and 180°, the expanding-gas operation without prior vitrectomy is worth trying because the results are favorable (see Chapter 10.6.1, pp. 167–212). When treating tears larger than 180°, or in the hands of some surgeons tears larger than 90°, the gas operation is combined with a prior vitrectomy. If in addition a rolled-over posterior flap of the giant tear has to be unfolded, the use of heavy perfluorocarbon liquids [3] as a mechanical tool is needed, although the manipulation with a small gas bubble may suffice [4]. This represents a detachment in which the tear was either closed primarily by a segmental buckle, but subsequently redetached—with no possibility of reattachment by the addition of a cerclage—or it was not closed off primarily by an external buckle due to excessive traction upon it. A gas operation will not help, on the contrary it may increase proliferative vitreoretinopathy. With vitrectomy the localized excessive traction can be removed. Admittedly, the finding of an excessive traction is rare; it was present in less than 2% in a series of 752 rhegmatogenous detachments [5]. Prior to the advent of vitrectomy, the presence of extensive circular vitreous traction was the indication for a cerclage. If the vitreous traction was not excessive, the retina might have been reattached with a constriction of the globe. However, the constriction should be not more than 15% because more constriction carries with it a marginal morbidity in terms of circulatory disturbances, which can jeopardize subsequent visual function (see Part 1, Chapter 8.11, pp. 195–204). In a primary detachment vitreous traction is usually mild. When present, it tends to be limited to 1 or 2 quadrants, manifested by starfolds. As discussed earlier, in these detachments it is worthwhile to try buckling first (see Part 1, Chapter 8.18.2–8.18.5, pp. 257–277). As you will recall, in a series of 107 consecutive detachments, there were 16 eyes with PVR grade C1 or C2 [6]. In another series of 72 selected detachments with moderate PVR (grade B in 22 eyes and grade C1 or C2 in 50 eyes), recruited out of 695 consecutive detachments, the retina reattached in 79% after buckling the tear, and in 86% after a 2nd buckling procedure [7]. – In 8 out of 10 detachments with PVR grade B, C1, or C2, the retina was reattached by an extraocular approach with a minimum of morbidity. – And a vitrectomy was not needed. Confronted with a vitreous hemorrhage of rhegmatogenous origin, a clearing of the optic media might result after double patching and elevating the patient’s head (see Part 1, Chapter 3, pp. 28–40). Even if the resulting view of the retina is not optimal, with skillful indirect ophthalmoscopy and depression of the anterior retina, either the breaks can be detected or the borders of the detachment determined.
12.1 Background
12.2 Limits of External Buckling
12.2.1 Due to Location or Size of Tear
Posterior holes
Group of breaks at different latitude
12.2.2 Due to Vitreous Traction
Excessive local traction on a tear
Extensive circular vitreous traction on the retina
What does this imply?
Even if vitreous traction is in 2 quadrants, manifested by starfolds, localized buckling might suffice:
12.2.3 Due to Opacities within the Optic Media
Vitreous hemorrhage
Why is this possible in the presence of a vitreous hemorrhage?
Because the blood is retrohyaloidally early after a rhegmatogenous hemorrhage and the anterior retina will not be obscured because the vitreous base is attached. Therefore, the view to the anterior retina is accessible with indirect ophthalmoscopy and simultaneous depression (see Part 1, Chapter 3.2, page 29, Fig. 3.1).
Tears larger than 70°
