5.3 Oil Retention Sutures

Complex retinal detachments, such as those after open globe injuries, often require silicone oil tamponade. In eyes with traumatic or surgical aphakia and an intact iris, an inferior peripheral iridectomy effectively keeps oil out of the anterior chamber. However, eyes with aphakia and aniridia represent a particular challenge. The lack of the lens-iris diaphragm is a relative contraindication to placement of silicone oil due to the risk of anterior migration of oil leading to elevated intraocular pressure (IOP), band keratopathy, bullous keratopathy and/or complete corneal decompensation, in addition to suboptimal tamponade. First described in 2010, silicone oil retention sutures can be placed just behind the limbus to prevent oil migration in these eyes[1], and they have been shown to successfully keep oil posteriorly in a number of reports.[1,2,3,4,5,6] It is important to understand that sufficient aqueous production is essential for this technique to work, as it is ineffective in cases of hypotony (IOP < ~5).

A number of suture configurations have been proposed. The most important part of any retention suture placement is that they be in the same plane in order to effectively barricade the oil. The various patterns that have been attempted include a triangular configuration, as shown in (Figure 5.3.1), hexagonal,[7] square,[1,5] and grid,[1,8] (Figure 5.3.2). In 2012, a modification was described whereby a suture is interwoven in the triangular configuration to further stabilize the plane (Figure 5.3.2).[9] All configurations have achieved successful silicone oil barricade, owing to the high surface tension of the oil.

Many reports have used ultrasound biomicroscopy with the patient in the supine position to show that the retention sutures prevent anterior oil migration.[1,5,8] In addition, we and others[7] have found that in a small subset of cases, a membrane forms in the plane of the retention sutures that creates a pseudo-iris. A central opening may form naturally, or one can use a capsulorrhexis technique to clear the visual axis.