EyeWorld Asia-Pacific June 2013 Issue

34 EWAP CAtArACt/IOL June 2013 Microbulldog silicone assistant for intrascleral haptic fixation of IOLs by Steven G. Safran, MD Growing interest in techniques for intrascleral haptic fixation leads to resurrection of this simple device U sing 1991, when I was a cornea fellow at Duke University, I came up with a design for a simple device called a “microbulldog.” This was a miniature soft silicone clamp that was designed to hold the 10-0 prolene used for scleral suturing of the IOL securely and temporarily during sutured in lens cases combined with penetrating keratoplasty. I was doing a lot of scleral fixated posterior chamber lenses combined with corneal grafts and found that I achieved better centration and positioning of the sutured IOL in an eye that had a formed AC and normal IOP rather than when it was hypotonous. The microbulldog would hold the 10-0 prolene that was passed through the sclera under tension while I completed the suturing of the cornea graft. After the graft was completed, the anterior chamber was reformed, the eye firmed up, the microbulldog removed, and the implant finally sutured in place by scleral fixation. When I started doing intrascleral haptic fixation of IOLs in the absence of capsular support, it became clear very quickly that it was time to resurrect the microbulldog. After externalizing the leading haptic through a sclerotomy, it is much easier to place the trailing haptic in the eye and feed it to an instrument to externalize it if an assistant is holding the first, lead haptic in place. Without this assist, the lead haptic can slip back into the eye, and it is pretty easy at that point to drop the lens onto the retina. Most of us who do this surgery don’t have an assistant we trust to gently hold that leading haptic without damaging it so that the surgeon can focus all of his attention on the trailing haptic. Here is a simple and inexpensive method of creating a microbulldog silicone assistant (MSA) to “cover your back.” All that is needed is a butterfly cannula, a 25-g needle, and a scissor. First, the butterfly cannula tubing is cut to create a fresh edge. Then, the 25-g needle is passed through the tip to engage the wall of the silicone cannula (Figure 1). At this point, a scissor is used to cut the tip of the silicone tubing almost flush with the needle, amputating this tip (Figure 2). The microbulldog is now loaded onto the 25-g needle and set aside (Figure 3). After the lead haptic of the secondary IOL is grasped and externalized through a sclerotomy, the 25-g needle with the microbulldog is brought onto the surgical field. The haptic is engaged within the lumen of the Figure 1. A 25-g needle is placed through the edge of a cut butterfly catheter tubing. Figure 2. Tubing is cut close to the edge where the needle is inserted to amputate the tip. Figure 3. The microbulldog silicone assistant is now “locked and loaded” and ready for use. Figures 4, 5, 6. Microbulldog silicone assistant is guided onto the haptic by inserting the haptic into the tip of the needle and sliding the MSA down over the haptic. Figure 8. Even pulling on the IOL will not cause slippage of the haptic through the MSA. It is very secure. Source (all): Steven G. Safran, MD Figure 7: MSA is now securely on tip of haptic. 25-g needle (Figure 4), and the microbulldog is then slid down over this haptic (Figures 5 and 6). At this point the silicone assistant is in place and will hold the haptic firmly (Figure 7). The shape of this tip is designed so that a great deal of pulling force can be resisted without damaging the haptic or slipping. The surgeon can now focus on the trailing haptic. While this trailing haptic is placed in the eye and passed to a microforceps to externalize it through a sclerotomy, continued on page 38