- Email: [email protected]
August consultation #3
1120
CONSULTATION SECTION: CATARACT
In this case, I would prefer 9-0 polypropylene (Prolene) (on-label) over 8-0 polytetrafluoroethylene (Gore-Tex) (off-label in the United States). Because the patient is 79 years old, the concern for suture degradation over time is less significant and polypropylene offers more needle design choices. An elegant and minimally invasive technique for IOL refixation in cases such as this was described by Kirk and Condon.1 If the IOL tilts posteriorly or needs additional stabilization before fixation, iris retractors can be strategically placed at the optic–haptic junctions. A dispersive ophthalmic viscosurgical device (OVD) should be injected to tamponade any vitreous, and care should be taken not to overfill the anterior chamber. If any vitreous prolapse around the IOL is noted, an anterior vitrectomy should be performed before suture fixation. If an anterior vitrectomy is required, an anterior chamber maintainer (ACM) should be considered to preserve IOP because suture passage can be difficult in soft eyes. With the current location of the IOL, it looks as though nasal–temporal suture placement is indicated. After the creation of small peritomies centered at 3 o’clock and 9 o’clock, care should be taken to carefully mark the location of the suture passages so they are 2.0 mm from the limbus and oriented directly across from each other to maximize IOL centration. Although this patient’s eyes appear to dilate well, iris retractors can be used to improve peripheral visualization in patients with suboptimal exposure. In the Kirk-Condon technique,1 an ab externo pass is made at 1 end of a scleral groove positioned between the marked entry points. A long, curved needle is passed under the haptic through the capsule and out through the peripheral cornea. The suture is retrieved with a J-hook or snare over the haptic through a sclerotomy placed at the other end of the scleral groove. The suture can be temporarily secured with a slipknot until the other haptic is sutured. The over passes and under passes on the other side should be oriented opposite to the first suture to decrease the risk for IOL tilt. Some surgeons advocate a vertical orientation of the suture passes to minimize this risk. After both sutures are placed, the tension can be adjusted to maximize IOL centration and the knots rotated into the sclerotomy. If any concern for vitreous prolapse remains, intracameral triamcinolone can be used to aid visualization and anterior vitrectomy. Although this technique has proven to be very successful, sometimes older IOLs are found to have fragile optic– haptic junctions intraoperatively. Given this risk, I recommend having a plan and all the necessary supplies for an IOL exchange if the current IOL will not support refixation. REFERENCE
1. Kirk TQ, Condon GP. Simplified ab externo scleral fixation for late in-the-bag intraocular lens dislocation. J Cataract Refract Surg 2012; 38:1711–1715. erratum, 2013; 39:489. Available at: http://www.jcrsjournal.org/article /S0886-3350(12)01150-9/pdf. Erratum available at: http://www.jcrsjournal .org/article/S0886-3350(13)00061-8/pdf. Accessed June 6, 2017
Volume 43 Issue 8 August 2017
Nicole R. Fram, MD Los Angeles, California, USA
Retinitis pigmentosa can present a challenging course for the patient and surgeon. As described, the classic clinical presentation includes the triad of peripheral pigment clumping (bone spicules), arteriolar narrowing, and optic nerve pallor. In addition, patients can present with posterior subcapsular cataract and zonular fiber weakness. This case involves an in-the-bag inferiorly dislocated 3-piece, PMMA posterior chamber IOL (PC IOL) causing gradual decreased vision years after uneventful cataract surgery. Although the IOL appears stable at the iris plane in Figure 1, evaluation in the supine position is necessary to assess whether the IOL is accessible from an anterior approach. If dislocation is too far posteriorly, having a retina colleague on standby is warranted. All patients requiring IOL repositioning or exchange should have preoperative endothelial cell counts and macular OCT performed, in particular because patients with retinitis pigmentosa can have macular edema as a sequel to their disease. There are 2 reasonable surgical plans. One could reposition the PC IOL with a lasso scleral suture fixation of the haptics (9-0 polypropylene or 8-0 polytetrafluoroethylene suture [off-label in the U.S.]) or perform an IOL exchange and secondary PC IOL with scleral suture fixation or intrascleral fixation. It is important to note that the 7.0 mm PMMA optic cannot be cut with microsurgical scissors and should be removed as 1 piece through a 7.5 mm scleral tunnel. The next consideration is to assess the capsular bag contents and amount of Soemmerring ring. A preoperative ultrasound biomicroscopy would be helpful to visualize the IOL position and Soemmerring ring. The reason this is useful is twofold: (1) Lasso scleral suture fixation is best achieved with a minimum amount of Soemmerring ring to avoid an in-the-bag, uveitis–glaucoma–hyphema (UGH) syndrome caused by the anteriorization of the IOL–capsular bag–Soemmerring complex and (2) the surgeon can plan for a Sheets glide use during IOL exchange of the IOL–capsular bag–Soemmerring complex to avoid inadvertent dropping of fragments to the posterior pole. The lasso scleral suture fixation technique seems to be the best approach in this case because of the minimum visible regenerative cortex and presence of a fibrotic anterior capsule. To achieve intraoperative IOL stabilization during IOL manipulation, a pars plana basket suture or “Masket basket” should be placed 90 degrees away from the planned fixation.1 This is accomplished by using a double-armed 9-0 polypropylene on a straight needle (STC-6, Ethicon, Inc.) bent 4.0 mm from the tip at a 30-degree angle that is subsequently docked into a 27-gauge needle 180 degrees away. The entrances of the needles should be 3.0 mm posterior to the limbus and 3.0 mm apart. Typically, 1 meridian basket suture is sufficient to stabilize the IOL for
CONSULTATION SECTION: CATARACT
intraoperative manipulation. A toric marker can then be used to mark the cornea at the haptic–optic junction on each side to ensure proper centration of the IOL. Next, a 23-gauge trocar can be placed 3.5 mm posterior to the limbus to allow for an anterior vitrectomy via a pars plana approach (with preservative-free triamcinolone) and later, posterior infusion. Then, make conjunctival peritomies in the same meridian as the haptic–optic junction for 3 clock hours and use calipers to measure the entry of sclerotomies. Use a 23-gauge microvitreoretinal-blade equivalent to create the sclerotomies, 1.5 mm and 3.0 mm posterior to the limbus in a radial fashion. This will avoid torque of the haptics caused by classic horizontal fixation without antitorque maneuvers. Aiming the sclerotomy entries posteriorly will avoid intersection with the iris root. Use an OVD throughout the procedure to protect the corneal endothelium. The haptics on each side can then be fixated with the lasso technique using polytetrafluoroethylene needleless recovery with a microsurgical 25-gauge forceps. In this scenario, 9-0 polypropylene might prove more accurate for final positioning. The knots can then be tied in a 1-1-1-1 slipknot and buried into the sclerotomy openings on each side. The knots and cut suture ends should be fully buried to avoid subconjunctival erosion. With this approach, the visual rehabilitation can be accomplished through small incisions that allow for fast visual rehabilitation. Last, all patients having IOL repositioning or exchange with anterior vitrectomy should be counseled regarding the risk for vitreous hemorrhage and have a careful retinal examination postoperatively to rule out retinal tear or detachment. REFERENCE
1. Masket S, Fram NR. Safety-basket suture for management of malpositioned posterior chamber intraocular lens. J Cataract Refract Surg 2013; 39:1633–1635. Available at: http://www.jcrsjournal.org/article /S0886-3350(13)01112-7/pdf. Accessed July 17, 2017
Stephen Lane, MD St. Paul, Minnesota, USA Zonular fiber insufficiency is not uncommon in patients with retinitis pigmentosa. Dikopf et al.1 found that approximately 19% of patients with retinitis pigmentosa had some degree of zonular fiber insufficiency. Therefore, the findings in this case are not unusual. In cases of a dislocated IOL within the capsular bag, regardless of cause, the surgeon’s decision for repair most often comes down to removal and replacement of the IOL or repositioning of the existing dislocated IOL. Most often, I prefer to reposition the IOL because it can usually be accomplished in a closed system with less surgery and often without vitrectomy. In this case with the IOL fibrosed within the capsule, an open posterior capsule, and a 3-piece IOL in place, repositioning might be challenging and many surgeons would opt to remove the IOL, perform a
1121
vitrectomy, and use a glued PC IOL or an anterior chamber IOL. A 3-piece IOL sutured to the iris should be discouraged as an alternative because of the high incidence of UGH syndrome secondary to the significant pseudophacodonesis that occurs in vitrectomized eyes. Despite the aforementioned challenges, I would choose to reposition the existing IOL. Actually, the significant fibrosis of the anterior capsule that overlaps the top half of the peripheral IOL optic is your ally in the repair of this dislocation. Condon has describedA and should be credited for a technique to repair IOL dislocations in cases exactly like this that I too have found extremely useful. I would make a paracentesis at approximately the 10 o’clock limbal position and 2 o’clock position and instill a cohesive OVD. I would undermine the area of the fibrosis at the edge of the IOL where it overlaps the IOL optic so the edge can be grasped with a microforceps that would fit through the paracentesis. Next, I would constrict the pupil to approximately 6.0 mm. Then, while grasping the edge of the fibrotic anterior capsule, I would place a 9-0 or 10-0 polypropylene suture on a long needle (CTC-6 [or equivalent], Ethicon, Inc.) through the 10 o’clock paracentesis through the midperipheral iris at around 11 o’clock; then, I would pass it through the edge (over the top) of the fibrotic capsule and out again through the midperipheral iris (coming from under the iris) at approximately the 12:30 o’clock point. I would pull it out through the peripheral clear cornea at the 1 to 2 o’clock position. I would retrieve the suture through the cornea at the 1 to 2 o’clock position through the 10 o’clock paracentesis, where I would apply a Siepser knot. This serves to fixate the fibrotic capsule rim to the midperipheral iris, which centers the IOL. I would then apply 2 more throws and cut the knot short with intraocular scissors. It is important that the bites through the iris be midperipheral so the IOL optic edge (at the fibrotic edge) comes to rest at the midperipheral iris to ensure IOL centration. You can appreciate how the fibrotic capsule is your friend here because it is tough enough that the suture will not cheese-wire through in the way it would if it were not fibrotic. In addition, as the suture is cinched down, it will cause slight ovalization and mild constriction of the pupil, ensuring good IOL centration. In this way with minimum intraocular invasion, a satisfactory result is obtained, the eye is not opened more than a paracentesis, and vitrectomy and excessive manipulation are avoided. REFERENCE
1. Dikopf MS, Chow CC, Mieler WF, Tu EY. Cataract extraction outcomes and the prevalence of zonular insufficiency in retinitis pigmentosa. Am J Ophthalmol 2013; 156:82–88
OTHER CITED MATERIAL A. Condon GP, “Fixation Frustration,” presented at the EyeWorld Surgical Summit. Innovative Techniques and Controversies in Ophthalmology, Park City, Utah, USA, February 2017
Volume 43 Issue 8 August 2017
CONSULTATION SECTION: CATARACT
In this case, I would prefer 9-0 polypropylene (Prolene) (on-label) over 8-0 polytetrafluoroethylene (Gore-Tex) (off-label in the United States). Because the patient is 79 years old, the concern for suture degradation over time is less significant and polypropylene offers more needle design choices. An elegant and minimally invasive technique for IOL refixation in cases such as this was described by Kirk and Condon.1 If the IOL tilts posteriorly or needs additional stabilization before fixation, iris retractors can be strategically placed at the optic–haptic junctions. A dispersive ophthalmic viscosurgical device (OVD) should be injected to tamponade any vitreous, and care should be taken not to overfill the anterior chamber. If any vitreous prolapse around the IOL is noted, an anterior vitrectomy should be performed before suture fixation. If an anterior vitrectomy is required, an anterior chamber maintainer (ACM) should be considered to preserve IOP because suture passage can be difficult in soft eyes. With the current location of the IOL, it looks as though nasal–temporal suture placement is indicated. After the creation of small peritomies centered at 3 o’clock and 9 o’clock, care should be taken to carefully mark the location of the suture passages so they are 2.0 mm from the limbus and oriented directly across from each other to maximize IOL centration. Although this patient’s eyes appear to dilate well, iris retractors can be used to improve peripheral visualization in patients with suboptimal exposure. In the Kirk-Condon technique,1 an ab externo pass is made at 1 end of a scleral groove positioned between the marked entry points. A long, curved needle is passed under the haptic through the capsule and out through the peripheral cornea. The suture is retrieved with a J-hook or snare over the haptic through a sclerotomy placed at the other end of the scleral groove. The suture can be temporarily secured with a slipknot until the other haptic is sutured. The over passes and under passes on the other side should be oriented opposite to the first suture to decrease the risk for IOL tilt. Some surgeons advocate a vertical orientation of the suture passes to minimize this risk. After both sutures are placed, the tension can be adjusted to maximize IOL centration and the knots rotated into the sclerotomy. If any concern for vitreous prolapse remains, intracameral triamcinolone can be used to aid visualization and anterior vitrectomy. Although this technique has proven to be very successful, sometimes older IOLs are found to have fragile optic– haptic junctions intraoperatively. Given this risk, I recommend having a plan and all the necessary supplies for an IOL exchange if the current IOL will not support refixation. REFERENCE
1. Kirk TQ, Condon GP. Simplified ab externo scleral fixation for late in-the-bag intraocular lens dislocation. J Cataract Refract Surg 2012; 38:1711–1715. erratum, 2013; 39:489. Available at: http://www.jcrsjournal.org/article /S0886-3350(12)01150-9/pdf. Erratum available at: http://www.jcrsjournal .org/article/S0886-3350(13)00061-8/pdf. Accessed June 6, 2017
Volume 43 Issue 8 August 2017
Nicole R. Fram, MD Los Angeles, California, USA
Retinitis pigmentosa can present a challenging course for the patient and surgeon. As described, the classic clinical presentation includes the triad of peripheral pigment clumping (bone spicules), arteriolar narrowing, and optic nerve pallor. In addition, patients can present with posterior subcapsular cataract and zonular fiber weakness. This case involves an in-the-bag inferiorly dislocated 3-piece, PMMA posterior chamber IOL (PC IOL) causing gradual decreased vision years after uneventful cataract surgery. Although the IOL appears stable at the iris plane in Figure 1, evaluation in the supine position is necessary to assess whether the IOL is accessible from an anterior approach. If dislocation is too far posteriorly, having a retina colleague on standby is warranted. All patients requiring IOL repositioning or exchange should have preoperative endothelial cell counts and macular OCT performed, in particular because patients with retinitis pigmentosa can have macular edema as a sequel to their disease. There are 2 reasonable surgical plans. One could reposition the PC IOL with a lasso scleral suture fixation of the haptics (9-0 polypropylene or 8-0 polytetrafluoroethylene suture [off-label in the U.S.]) or perform an IOL exchange and secondary PC IOL with scleral suture fixation or intrascleral fixation. It is important to note that the 7.0 mm PMMA optic cannot be cut with microsurgical scissors and should be removed as 1 piece through a 7.5 mm scleral tunnel. The next consideration is to assess the capsular bag contents and amount of Soemmerring ring. A preoperative ultrasound biomicroscopy would be helpful to visualize the IOL position and Soemmerring ring. The reason this is useful is twofold: (1) Lasso scleral suture fixation is best achieved with a minimum amount of Soemmerring ring to avoid an in-the-bag, uveitis–glaucoma–hyphema (UGH) syndrome caused by the anteriorization of the IOL–capsular bag–Soemmerring complex and (2) the surgeon can plan for a Sheets glide use during IOL exchange of the IOL–capsular bag–Soemmerring complex to avoid inadvertent dropping of fragments to the posterior pole. The lasso scleral suture fixation technique seems to be the best approach in this case because of the minimum visible regenerative cortex and presence of a fibrotic anterior capsule. To achieve intraoperative IOL stabilization during IOL manipulation, a pars plana basket suture or “Masket basket” should be placed 90 degrees away from the planned fixation.1 This is accomplished by using a double-armed 9-0 polypropylene on a straight needle (STC-6, Ethicon, Inc.) bent 4.0 mm from the tip at a 30-degree angle that is subsequently docked into a 27-gauge needle 180 degrees away. The entrances of the needles should be 3.0 mm posterior to the limbus and 3.0 mm apart. Typically, 1 meridian basket suture is sufficient to stabilize the IOL for
CONSULTATION SECTION: CATARACT
intraoperative manipulation. A toric marker can then be used to mark the cornea at the haptic–optic junction on each side to ensure proper centration of the IOL. Next, a 23-gauge trocar can be placed 3.5 mm posterior to the limbus to allow for an anterior vitrectomy via a pars plana approach (with preservative-free triamcinolone) and later, posterior infusion. Then, make conjunctival peritomies in the same meridian as the haptic–optic junction for 3 clock hours and use calipers to measure the entry of sclerotomies. Use a 23-gauge microvitreoretinal-blade equivalent to create the sclerotomies, 1.5 mm and 3.0 mm posterior to the limbus in a radial fashion. This will avoid torque of the haptics caused by classic horizontal fixation without antitorque maneuvers. Aiming the sclerotomy entries posteriorly will avoid intersection with the iris root. Use an OVD throughout the procedure to protect the corneal endothelium. The haptics on each side can then be fixated with the lasso technique using polytetrafluoroethylene needleless recovery with a microsurgical 25-gauge forceps. In this scenario, 9-0 polypropylene might prove more accurate for final positioning. The knots can then be tied in a 1-1-1-1 slipknot and buried into the sclerotomy openings on each side. The knots and cut suture ends should be fully buried to avoid subconjunctival erosion. With this approach, the visual rehabilitation can be accomplished through small incisions that allow for fast visual rehabilitation. Last, all patients having IOL repositioning or exchange with anterior vitrectomy should be counseled regarding the risk for vitreous hemorrhage and have a careful retinal examination postoperatively to rule out retinal tear or detachment. REFERENCE
1. Masket S, Fram NR. Safety-basket suture for management of malpositioned posterior chamber intraocular lens. J Cataract Refract Surg 2013; 39:1633–1635. Available at: http://www.jcrsjournal.org/article /S0886-3350(13)01112-7/pdf. Accessed July 17, 2017
Stephen Lane, MD St. Paul, Minnesota, USA Zonular fiber insufficiency is not uncommon in patients with retinitis pigmentosa. Dikopf et al.1 found that approximately 19% of patients with retinitis pigmentosa had some degree of zonular fiber insufficiency. Therefore, the findings in this case are not unusual. In cases of a dislocated IOL within the capsular bag, regardless of cause, the surgeon’s decision for repair most often comes down to removal and replacement of the IOL or repositioning of the existing dislocated IOL. Most often, I prefer to reposition the IOL because it can usually be accomplished in a closed system with less surgery and often without vitrectomy. In this case with the IOL fibrosed within the capsule, an open posterior capsule, and a 3-piece IOL in place, repositioning might be challenging and many surgeons would opt to remove the IOL, perform a
1121
vitrectomy, and use a glued PC IOL or an anterior chamber IOL. A 3-piece IOL sutured to the iris should be discouraged as an alternative because of the high incidence of UGH syndrome secondary to the significant pseudophacodonesis that occurs in vitrectomized eyes. Despite the aforementioned challenges, I would choose to reposition the existing IOL. Actually, the significant fibrosis of the anterior capsule that overlaps the top half of the peripheral IOL optic is your ally in the repair of this dislocation. Condon has describedA and should be credited for a technique to repair IOL dislocations in cases exactly like this that I too have found extremely useful. I would make a paracentesis at approximately the 10 o’clock limbal position and 2 o’clock position and instill a cohesive OVD. I would undermine the area of the fibrosis at the edge of the IOL where it overlaps the IOL optic so the edge can be grasped with a microforceps that would fit through the paracentesis. Next, I would constrict the pupil to approximately 6.0 mm. Then, while grasping the edge of the fibrotic anterior capsule, I would place a 9-0 or 10-0 polypropylene suture on a long needle (CTC-6 [or equivalent], Ethicon, Inc.) through the 10 o’clock paracentesis through the midperipheral iris at around 11 o’clock; then, I would pass it through the edge (over the top) of the fibrotic capsule and out again through the midperipheral iris (coming from under the iris) at approximately the 12:30 o’clock point. I would pull it out through the peripheral clear cornea at the 1 to 2 o’clock position. I would retrieve the suture through the cornea at the 1 to 2 o’clock position through the 10 o’clock paracentesis, where I would apply a Siepser knot. This serves to fixate the fibrotic capsule rim to the midperipheral iris, which centers the IOL. I would then apply 2 more throws and cut the knot short with intraocular scissors. It is important that the bites through the iris be midperipheral so the IOL optic edge (at the fibrotic edge) comes to rest at the midperipheral iris to ensure IOL centration. You can appreciate how the fibrotic capsule is your friend here because it is tough enough that the suture will not cheese-wire through in the way it would if it were not fibrotic. In addition, as the suture is cinched down, it will cause slight ovalization and mild constriction of the pupil, ensuring good IOL centration. In this way with minimum intraocular invasion, a satisfactory result is obtained, the eye is not opened more than a paracentesis, and vitrectomy and excessive manipulation are avoided. REFERENCE
1. Dikopf MS, Chow CC, Mieler WF, Tu EY. Cataract extraction outcomes and the prevalence of zonular insufficiency in retinitis pigmentosa. Am J Ophthalmol 2013; 156:82–88
OTHER CITED MATERIAL A. Condon GP, “Fixation Frustration,” presented at the EyeWorld Surgical Summit. Innovative Techniques and Controversies in Ophthalmology, Park City, Utah, USA, February 2017
Volume 43 Issue 8 August 2017