Eyeworld

EW NEWS & OPINION 12 R epair of the traumatic iridodialysis can be accomplished by means of single or multiple McCannel sutures through an ab externo approach or utilizing one or more double-armed sutures with an ab interno method. When fixating anything to the sclera, it is important to rotate the suture knots into the sclera or cover the suture knots under a scleral flap in order to prevent erosion of the overlying conjunctiva, which could then allow for the development of subsequent endophthalmitis. Al- though suture knot rotation is rela- tively simple and straightforward, an alternative method of repairing a traumatic iridodialysis utilizes one or more sclera pockets that eliminate the need for a conjunctival peritomy but still enable covering of the su- ture knot without the need for knot rotation. If the iridodialysis is 3 clock hours or less, one double-armed pro- lene suture and one pocket is all that is required. For larger dialyses, two pockets will be needed (Figure 1). The first step is to place a 350 micron deep grooved incision at the clear cornea limbus overlying the middle third of the dialysis. For large dialyses, two grooves of 2 clock hour lengths are placed (Figure 2). Each grooved incision is then dissected posteriorly in the plane of the sclera for approximately 2 mm to create a scleral pocket (Figure 3). Utilizing a metal crescent blade and lifting up on the posterior edge of the grooved incision during the dis- section facilitates creation of the scleral pocket. Once the pockets are dissected, the conjunctival surface overlying the lateral extent of each pocket is marked with gentian violet to assist in correct suture needle placement (Figure 4). A paracentesis is then made 3-4 clock hours from the site of fixation and a viscoelastic is injected into the anterior chamber. A 10-0 prolene su- ture on a double-armed CIF4 needle is passed through the paracentesis, incorporating the edge of the dial- ysed iris root one-third the lateral distance from the attached edge of the iris root. The needle is then passed through the full thickness of the globe, exiting approximately 2 mm posterior to the limbus within the area of the dissected pocket (Figure 5). The second arm of the double- armed suture is then passed through the same paracentesis, through the iris root edge, 3 mm adjacent to the first pass, and out through the sclera 2-3 mm adjacent to the first pass and 2 mm posterior to the limbus. It is better to err on passing the needle posterior to the original insertion rather than anterior in order to avoid obstructing the trabecular meshwork. Wiggling the needle tip back and forth as it goes through the paracentesis will avoid accidently passing the suture needle through corneal stroma. Placing the vis- coelastic cannula into the paracente- July 2011 by Richard S. Hoffman, M.D. Iridodialysis repair through a scleral pocket T here is more than one way to skin a cat. Whether it is sewing in an IOL, performing a penetrating or lamellar keratoplasty, or removing a cataract, varied approaches and techniques can be used to arrive at the same final endpoint with each approach perhaps having its own distinct advantages. Several years ago, I found that the use of a scleral pocket to fixate dislo- cated IOLs allowed for the ability to cover scleral knots without the need to rotate the knot into the sclera. It also had the advan- tage of avoiding the need for scleral cau- terization or conjunctival dissection. I have subsequently found that a scleral pocket could be used for fixation of secondary IOLs, capsular prosthetic devices, and basi- cally any instance where something needs to be fixated to the globe. In this month's column, I present an alter- native method for repairing iridodialyses that utilizes a scleral pocket for fixation of the disinserted iris root. It is of course not the only method, the best method, or the fastest method for iridodialysis repair, but it does offer a different approach for repair that might be advantageous in some select patients. I hope you find the article and the linked video helpful in answering any questions regarding this technique. What I cannot answer is why one would want to skin a cat in the first place. Richard S. Hoffman, M.D. Column Editor Figure 5 Figure 6 Figure 8 Source: Richard S. Hoffman, M.D. Figure 7 Figure 1 Figure 2 Figure 4 Figure 3 continued on page 14 See the video of Dr. Hoffman's procedure at http://www.eyeworld.org/ replay.php rePlay online content

• Cover