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February Consultation #6
190
CONSULTATION SECTION
9-0 Prolene. However, the best suture material is a subject of discussion and future investigation. Boris Malyugin, MD, PhD Moscow, Russia
- This patient presents with a subluxated IOL in the bag with a CTR. Significant features are the absence of obvious vitreous prolapse and the lack of an Nd:YAG laser posterior capsulotomy. Before proceeding, the surgeon should confirm the absence of vitreous in the anterior chamber with triamcinolone or trypan blue as this will need to be managed appropriately. There are 3 options for management. The first is to explant the IOL–CTR complex and secondarily implant an anterior chamber IOL. This approach runs the risk of disrupting the anterior vitreous face, which currently appears intact, and thereby potentially inducing a host of adverse outcomes. Furthermore, the removal and reimplantation of an IOL and the presence of an anterior chamber IOL itself could potentiate endothelial cell loss. The approach also requires a 6.0 mm incision and suture closure. The second option is to reposition and refixate the subluxated posterior chamber IOL–CTR complex with iris sutures. This approach is limited as the additional bulk of the capsule–zonule complex, along with the posterior chamber IOL, would increase the area of the IOL in contact with the posterior aspect of the iris and thus increase the likelihood of pigment dispersion, uveitis, hyphema, and secondary glaucoma. Iris fixation could have been the preferred technique had the posterior chamber IOL not been a 1-piece model and had been initially implanted in the sulcus and then subluxated. The third choice would be ab externo scleral fixation of the CTR complex in the following manner: The midpoint of the arc of the CTR subluxation (approximately at the 1:30 position) is ideally where the sutures should be placed. I would first suture the part of the CTR that has subluxated toward the visual axis. After performing a peritomy from the 12:30 to 2:30 position, I would perform cautery to achieve hemostasis. Using a guarded diamond blade or a reasonable substitute, I would make a 50% thickness vertical and circumferential scleral incision 1.5 mm posterior to the surgical limbus and 1.5 mm in length. After creating a paracentesis at the 6:30 position, I would inject OVD into the anterior chamber and, particularly, the posterior chamber in the area where the CTR is to be sutured to create the necessary space between the capsule and the iris. I would also attempt to reform the capsular bag. A double-armed 10-0
polypropylene suture on a CIF-4 needle (Ethicon Inc.) or a PC-7 needle (Alcon Laboratories, Inc.) or a 9-0 polypropylene suture on a CTC-6L needle would be appropriate. The latter suture has a lower risk for late breakage and is therefore preferred. The needle is passed into the anterior chamber, over the optic, and under the CTR so that it penetrates the capsule. A second instrument (ideally, an Ahmed microforceps [Microsurgical Technologies]) that could support the IOL–capsule complex through a second paracentesis would facilitate this maneuver. The needle must pass through the paracentesis or a false passage will capture corneal tissue in the suture and prevent the loop from entering the anterior chamber. After successful passage of the suture under the CTR, I would place a 26-gauge needle, bent at the hub, into the posterior chamber at either of the lateral edges of the partial-thickness scleral incision. The tip of the suture needle would then be captured in the lumen of the 26-gauge needle and externalized through the sclera. I would repeat the process with the other end of the 10-0 polypropylene suture, this time passing it over the CTR and externalizing the suture on the other lateral edge of the scleral incision. I would tie the suture ends in a releasable fashion to allow for the titration of tension after the placement of the second suture. The applied tension on the suture would center the capsule–IOL complex, facilitating visualization of the second side of the CTR for suturing, if needed. After titrating both sutures (if needed) for tension and tying them in the usual fashion, I would rotate the knots so that they are located in the posterior chamber. This technique minimizes the risk for conjunctival erosion over the knots as well as erosion of the suture through the sclera. At this point, the IOL should recenter successfully. If not, it may have to be repositioned with the use of an OVD and Kuglen hooks. Rosa Braga-Mele, MD, MEd, FRCSC Toronto, Ontario, Canada
- The intraoperative image tells the whole story in this case. There is obvious lack of zonular support in the superotemporal quadrant, resulting in reciprocal subluxation of the IOL–bag–CTR complex. In the 5 years since the original surgery, there has likely been increasing decentration associated with capsule contraction. The saving grace is the previously wellplaced CTR, which now provides the option of scleral refixation in any preferred meridian. The visible IOL haptic is directed toward the inferotemporal zone and would not be a usable support structure on its
J CATARACT REFRACT SURG - VOL 34, FEBRUARY 2008
CONSULTATION SECTION
9-0 Prolene. However, the best suture material is a subject of discussion and future investigation. Boris Malyugin, MD, PhD Moscow, Russia
- This patient presents with a subluxated IOL in the bag with a CTR. Significant features are the absence of obvious vitreous prolapse and the lack of an Nd:YAG laser posterior capsulotomy. Before proceeding, the surgeon should confirm the absence of vitreous in the anterior chamber with triamcinolone or trypan blue as this will need to be managed appropriately. There are 3 options for management. The first is to explant the IOL–CTR complex and secondarily implant an anterior chamber IOL. This approach runs the risk of disrupting the anterior vitreous face, which currently appears intact, and thereby potentially inducing a host of adverse outcomes. Furthermore, the removal and reimplantation of an IOL and the presence of an anterior chamber IOL itself could potentiate endothelial cell loss. The approach also requires a 6.0 mm incision and suture closure. The second option is to reposition and refixate the subluxated posterior chamber IOL–CTR complex with iris sutures. This approach is limited as the additional bulk of the capsule–zonule complex, along with the posterior chamber IOL, would increase the area of the IOL in contact with the posterior aspect of the iris and thus increase the likelihood of pigment dispersion, uveitis, hyphema, and secondary glaucoma. Iris fixation could have been the preferred technique had the posterior chamber IOL not been a 1-piece model and had been initially implanted in the sulcus and then subluxated. The third choice would be ab externo scleral fixation of the CTR complex in the following manner: The midpoint of the arc of the CTR subluxation (approximately at the 1:30 position) is ideally where the sutures should be placed. I would first suture the part of the CTR that has subluxated toward the visual axis. After performing a peritomy from the 12:30 to 2:30 position, I would perform cautery to achieve hemostasis. Using a guarded diamond blade or a reasonable substitute, I would make a 50% thickness vertical and circumferential scleral incision 1.5 mm posterior to the surgical limbus and 1.5 mm in length. After creating a paracentesis at the 6:30 position, I would inject OVD into the anterior chamber and, particularly, the posterior chamber in the area where the CTR is to be sutured to create the necessary space between the capsule and the iris. I would also attempt to reform the capsular bag. A double-armed 10-0
polypropylene suture on a CIF-4 needle (Ethicon Inc.) or a PC-7 needle (Alcon Laboratories, Inc.) or a 9-0 polypropylene suture on a CTC-6L needle would be appropriate. The latter suture has a lower risk for late breakage and is therefore preferred. The needle is passed into the anterior chamber, over the optic, and under the CTR so that it penetrates the capsule. A second instrument (ideally, an Ahmed microforceps [Microsurgical Technologies]) that could support the IOL–capsule complex through a second paracentesis would facilitate this maneuver. The needle must pass through the paracentesis or a false passage will capture corneal tissue in the suture and prevent the loop from entering the anterior chamber. After successful passage of the suture under the CTR, I would place a 26-gauge needle, bent at the hub, into the posterior chamber at either of the lateral edges of the partial-thickness scleral incision. The tip of the suture needle would then be captured in the lumen of the 26-gauge needle and externalized through the sclera. I would repeat the process with the other end of the 10-0 polypropylene suture, this time passing it over the CTR and externalizing the suture on the other lateral edge of the scleral incision. I would tie the suture ends in a releasable fashion to allow for the titration of tension after the placement of the second suture. The applied tension on the suture would center the capsule–IOL complex, facilitating visualization of the second side of the CTR for suturing, if needed. After titrating both sutures (if needed) for tension and tying them in the usual fashion, I would rotate the knots so that they are located in the posterior chamber. This technique minimizes the risk for conjunctival erosion over the knots as well as erosion of the suture through the sclera. At this point, the IOL should recenter successfully. If not, it may have to be repositioned with the use of an OVD and Kuglen hooks. Rosa Braga-Mele, MD, MEd, FRCSC Toronto, Ontario, Canada
- The intraoperative image tells the whole story in this case. There is obvious lack of zonular support in the superotemporal quadrant, resulting in reciprocal subluxation of the IOL–bag–CTR complex. In the 5 years since the original surgery, there has likely been increasing decentration associated with capsule contraction. The saving grace is the previously wellplaced CTR, which now provides the option of scleral refixation in any preferred meridian. The visible IOL haptic is directed toward the inferotemporal zone and would not be a usable support structure on its
J CATARACT REFRACT SURG - VOL 34, FEBRUARY 2008