The CTR is a useful multipurpose device that effectively supplements the currently available IOL armamentarium in complicated cases. The rotation of the plunger is stopped as soon as the gel foam is close to the terminal end to prevent foam from entering the anterior chamber. This releases the receding end of the CTR beneath the anterior capsule so the CTR lies in the capsular fornix. To release the distal end beneath the anterior capsule, the tip of the cartridge is placed beneath the anterior capsule and the plunger is rotated until the gel foam is close to the tip ( Figure 1, E and F). The plunger is rotated to release the CTR farther. The position of the cartridge is adjusted to keep the curve of the CTR horizontal. The plunger is rotated so the CTR tip protrudes from it below the anterior capsule. The tip of the cartridge is placed below the anterior capsule edge (usually in the quadrant with zonulodialysis or its neighboring area). The tip of the cartridge is introduced into the anterior chamber through a 2.8 or 3.2 mm clear corneal tunnel. If CTR insertion is planned after phacoemulsification, the capsular bag is also inflated with Healon GV. The anterior chamber is deepened with sodium hyaluronate 1.4% (Healon GV). The CTR can be inserted after creation of an anterior capsulorhexis or at the completion of phacoemulsification, depending on the surgeon's preference and the individual case. The CTR (Madhu Instruments) is held with a McPherson forceps and inserted through the distal-tube–like end of the cartridge until it is completely inside the cartridge ( Figure 1, B, C, and D). The silicone tip is applied to the top of the plunger in cases using the Silver Series only. The cartridge is then loaded onto the Unfolder implantation system. E, F: The CTR is released from the cartridge by rotating the plunger, which pushes the white gel foam and the CTR forward. D: The CTR is completely within the cartridge. B, C: The CTR is inserted into the distal tube with a McPherson forceps. A: A 2.0 mm gel-foam plug is introduced into the proximal end of the cartridge. Figure 1:Ĭapsular tension ring insertion into the Unfolder Silver Series implantation system cartridge. The gel-foam button is plugged into the proximal end of the closed cartridge ( Figure 1, A). A round button of approximately 2.0 mm is marked and cut from white gel foam (which comes as suture-needle–carrying material in the 10-0 monofilament nylon suture (Ethicon Inc.) with the corneoscleral scissors. The 2 flaps of the Silver or Sapphire Series cartridge are closed. We describe the use of the Unfolder Silver/Sapphire Series implantation system (Advanced Medical Optics, Inc.), designed to implant the SI40 or Sensar intraocular lens (IOL), to insert a CTR into the capsular bag. However, injecting devices are not always available, especially in developing countries. 7 The injecting system permits controlled, slow release of the leading edge below the anterior capsule. 5,8 Premature release of the trailing end of the CTR above the capsulorhexis opening may result in sudden lateral movement of the CTR, which may hit the ocular wall in the ciliary body area and push the entire capsular bag in the opposite direction, resulting in extension of the zonulysis. The injecting devices have made the sometimes demanding implantation procedure easier, faster, and safer. The CTR can be inserted with the help of a forceps, with or without guiding sutures, or an injector. Instructions for CTR insertion, problems related to their insertion, and measures to prevent the problems have been described. They maintain the circular contour of the capsular bag during cataract surgery and prevent vitreous prolapse into the anterior chamber in cases of zonulysis. 1,2 Capsular tension rings (CTRs) have proved to be useful devices in cataract surgery in cases of zonular weakness and dialysis. Insertion of a ring into the capsular bag fornix (equator) to support the zonular apparatus was first described by Hara et al.
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