- Email: [email protected]
February Consultation #3
CONSULTATION SECTION
- The case history shows blunt facial trauma occurring 5 years earlier with no history of direct trauma to the eye. This, the reported angle-closure glaucoma, and the phacodonesis indicate a preexisting general weakness of the entire zonular apparatus. There is no mention of whether pseudoexfoliation material was detected at the pupillary margin. If there was preexisting general zonular deficiency, the contusional trauma may have induced a sudden step forward in the otherwise protracted general degradation of the zonular apparatus by the coup–contrecoup mechanism. This is supported by the surgical protocol, which reports moderate phacodonesis and makes no mention of a well-defined zonular dialysis. Figure 1 shows that the entire capsule–IOL complex is subluxated, and modest phacodonesis is described. If there is no zonular support along the temporal and upper quadrants, recentering the capsule–IOL complex may be only transiently successful; it may even cause instant failure of the residual zonules while putting them under stress during manipulation. However, this could be considered a primary option if the procedure is straightforward and simple to perform. The other option would be to exchange the entire capsule–IOL complex for an alternatively fixated IOL. My general strategy would be the following: I would first judge the strength of the residual zonular apparatus by exploring at the slitlamp the amount of pseudophakodonesis with microsaccadic eye movements. During this examination, I would ask the patient to look to the side and back again and gently knock the globe at the limbus. Also, I would search for signs of pseudoexfoliation syndrome, including in the fellow eye. If the zonules appeared strong enough to provide sufficient support, even under tension, I would first try to surgically recenter the capsule–IOL complex by sulcus suturing. In any case, I would be prepared to explant the entire complex and would keep an exchange IOL ready. Surgery would begin with the administration of topical and intracameral anesthesia or peribulbar anesthesia. I would create a limbus-based conjunctival flap at the temporal and upper circumferences, make a paracentesis at the 7:30 position, and exchange the aqueous for a cohesive OVD such as Healon (sodium hyaluronate 1%). I would then push back the anterior hyaloid surface in the area of dialysis, preferably by creating a shell of adhesive OVD such as Viscoat (sodium hyaluronate 3.0%–chondroitin sulfate 4.0%) as it is not easily aspirated when the cohesive OVD is removed at the end of surgery. Should rupture of the anterior hyaloid with prolapsing vitreous be detected at the slitlamp before surgery, the vitreous, depending on the amount, could be pushed back with OVD or removed by localized bimanual translimbal vitrectomy.
187
A 30-gauge hypodermic needle bent at the middle with the bevel facing upward would then be used to perpendicularly penetrate the sclera ab externo at the 1:30 position less than 1.0 mm behind the posterior surgical limbus. This would likely penetrate the sulcus, as shown in postmortem eyes.1 On penetration, the tip of the needle would be redirected into the horizontal plane and advanced into the OVD cushion that separates the capsule–IOL complex from the anterior hyaloid until it reaches the capsule periphery, just inside the CTR. Then, 1 of the long straight needles of a double-armed 10-0 Prolene suture (Ethicon STC-6) would be inserted through the opposite paracentesis and fed into the needle opening, penetrating the fused capsule leaves just inside the CTR. As the hypodermic needle was retracted, the suture needle would be brought out of the globe. Then, the globe would be penetrated again about 2.0 mm lateral to the primary site, with the needle tip guided in front of the CTR. The second needle of the double-armed Prolene suture would then be inserted through the paracentesis and fed into the needle opening to again be delivered out of the eye. The 2 needles would be removed from the suture ends, but the ends would not yet be knotted. Before the ends were knotted, the cohesive OVD would be carefully aspirated through the paracentesis using a manual dry aspiration technique while the eye is intermittently repressurized with balanced salt solution (BSS). The viscoadhesive cushion at the dialysis area would be left untouched and would not inadvertently follow the aspiration flow due to its lack of cohesiveness. No attempt would be made to completely remove the cohesive OVD. After the bulk of the OVD was aspirated, the anterior chamber would be carefully rinsed with BSS to further reduce the residual amount without jeopardizing the hyaloid surface at the site of dialysis. The paracentesis would be sealed by stromal hydration. Only then (ie, with the OVD removed and the globe pressurized) would the Prolene sutures be knotted outside the eye and their tension carefully adjusted until the capsule–IOL diaphragm was perfectly centered. Then, the suture loop would be rotated until the knot was buried in the eye. An intracameral miotic such as Miochol (acetylcholine chloride) would be injected through the paracentesis to constrict the pupil, and a bolus of cefuroxime would be given for antibiosis. I recommend using pressure-lowering drops and postoperative pressure monitoring to detect and treat a possible pressure peak. Should the residual zonule provide insufficient support on surgical exploration, I would switch to IOL exchange. Two options could be considered. The first is a temporal approach, in which the IOL optic, CTR, and capsular bag would be cut in half for removal
J CATARACT REFRACT SURG - VOL 34, FEBRUARY 2008
188
CONSULTATION SECTION
through a 3.5 mm limbal incision and implantation of a foldable IOL, to be sutured in the sulcus. The second is a superior approach, in which the entire capsule– IOL diaphragm would be removed flat through a 5.8 mm incision and an iris-fixated anterior chamber poly(methyl methacrylate) (PMMA) IOL (Artisan, Ophtec) implanted. I prefer the latter approach as cutting and removing the CTR and IOL within the fused capsules through a small incision requires more intraocular manipulation with a greater risk for vitreous involvement. In contrast, explantation of the unfolded bulk through the wider incision required for implantation of the PMMA IOL is easier, fixation of the IOL to the iris is simple and perfectly controlled, and endothelial problems with this IOL will not occur in a deep aphakic chamber. Rupert Menapace, MD Vienna, Austria REFERENCE 1. Duffey RJ, Holland EJ, Agapitos PJ, Lindstrom RL. Anatomic study of transsclerally sutured intraocular lens implantation. Am J Ophthalmol 1989; 108:300–309
- In this case of a subluxated 1-piece acrylic posterior chamber IOL–CTR–capsular bag complex without vitreous prolapse, surgical management should proceed as our experience has been that progressive decentration with ultimate dislocation is likely to occur in these circumstances. Management of the PCO should be deferred until after surgical management of the subluxation. The first surgical decision is to determine whether IOL repositioning or IOL exchange is indicated. Considering the advantages of smaller incisions, minimal invasiveness, reduction in intraoperative manipulation and trauma, and the reduced likelihood of vitreous prolapse and/or the need for vitrectomy, our preference is to proceed with IOL suture repositioning as opposed to exchange. The next surgical decision is to determine the appropriate repositioning strategy. Although helpful for other IOL designs and circumstances, removal of the IOL from the capsular bag and fixation to the iris would not be appropriate here considering the potential technical difficulties in suturing the flexible haptics to the posterior iris and the postoperative risk for pigment dispersion from the bulky acrylic haptics and planar optic design. Thus, our preference would be an ab externo scleral suture fixation method to loop and recenter the IOL– CTR–capsular bag complex, as we have described.1,2 Briefly, a short 26-gauge hypodermic needle is placed
Figure 2. Scleral suturing of dislocated IOL–CTR–capsular bag complex. A 9-0 polypropylene suture needle passed through a paracentesis (left) is docked in a 26-gauge short hypodermic needle (right) passed through sclera 1.5 mm posterior to the limbus. The 26-gauge needle has passed beneath the CTR, through the fused posterior and anterior capsule leaflets, and into the anterior chamber. The docked 9-0 polypropylene suture and 26-gauge needle are then retracted from the eye through the scleral entry point.
through a scleral groove 1.5 mm posterior to the limbus. The first pass is placed under the CTR, through both leaflets of the fused anterior and posterior capsules and into the anterior chamber, where 1 end of a double-armed 9-0 polypropylene suture (Ethicon) is docked into the 26-gauge needle, which is then pulled back out through the scleral groove (Figure 2). A similar second pass is made adjacent to the first pass, but anterior to the CTR and capsule. This results in a suture loop around the CTR that, when tightened and knotted externally, will reposition the capsular bag complex. The polypropylene knot is ultimately rotated into the sclera to prevent extrusion. Scleral fixation should be performed in the area of zonular dehiscencedin this case, superotemporally. A single fixation point may be sufficient; however, intraoperative assessment of overall support should be ascertained before this decision is made. In these circumstances, the presence of a CTR as the backbone of the capsular bag often provides adequate centration and support when 1 suture is placed in the area of greatest zonular weakness, particularly when it is placed superiorly. If necessary, a second, and sometimes third point of fixation may be placed to support the entire complex. Although suture fixation of each haptic in cases of in-the-bag posterior chamber IOL subluxation is an effective method,2 2-point fixation, 180 degrees apart, of a CTR in the capsular bag carries an increased risk for tilt. Thus, if necessary, 3-point fixation to the sclera, each placed 120 degrees from each other, is preferred in cases of profound zonular instability in the presence of a CTR in the bag.
J CATARACT REFRACT SURG - VOL 34, FEBRUARY 2008
- The case history shows blunt facial trauma occurring 5 years earlier with no history of direct trauma to the eye. This, the reported angle-closure glaucoma, and the phacodonesis indicate a preexisting general weakness of the entire zonular apparatus. There is no mention of whether pseudoexfoliation material was detected at the pupillary margin. If there was preexisting general zonular deficiency, the contusional trauma may have induced a sudden step forward in the otherwise protracted general degradation of the zonular apparatus by the coup–contrecoup mechanism. This is supported by the surgical protocol, which reports moderate phacodonesis and makes no mention of a well-defined zonular dialysis. Figure 1 shows that the entire capsule–IOL complex is subluxated, and modest phacodonesis is described. If there is no zonular support along the temporal and upper quadrants, recentering the capsule–IOL complex may be only transiently successful; it may even cause instant failure of the residual zonules while putting them under stress during manipulation. However, this could be considered a primary option if the procedure is straightforward and simple to perform. The other option would be to exchange the entire capsule–IOL complex for an alternatively fixated IOL. My general strategy would be the following: I would first judge the strength of the residual zonular apparatus by exploring at the slitlamp the amount of pseudophakodonesis with microsaccadic eye movements. During this examination, I would ask the patient to look to the side and back again and gently knock the globe at the limbus. Also, I would search for signs of pseudoexfoliation syndrome, including in the fellow eye. If the zonules appeared strong enough to provide sufficient support, even under tension, I would first try to surgically recenter the capsule–IOL complex by sulcus suturing. In any case, I would be prepared to explant the entire complex and would keep an exchange IOL ready. Surgery would begin with the administration of topical and intracameral anesthesia or peribulbar anesthesia. I would create a limbus-based conjunctival flap at the temporal and upper circumferences, make a paracentesis at the 7:30 position, and exchange the aqueous for a cohesive OVD such as Healon (sodium hyaluronate 1%). I would then push back the anterior hyaloid surface in the area of dialysis, preferably by creating a shell of adhesive OVD such as Viscoat (sodium hyaluronate 3.0%–chondroitin sulfate 4.0%) as it is not easily aspirated when the cohesive OVD is removed at the end of surgery. Should rupture of the anterior hyaloid with prolapsing vitreous be detected at the slitlamp before surgery, the vitreous, depending on the amount, could be pushed back with OVD or removed by localized bimanual translimbal vitrectomy.
187
A 30-gauge hypodermic needle bent at the middle with the bevel facing upward would then be used to perpendicularly penetrate the sclera ab externo at the 1:30 position less than 1.0 mm behind the posterior surgical limbus. This would likely penetrate the sulcus, as shown in postmortem eyes.1 On penetration, the tip of the needle would be redirected into the horizontal plane and advanced into the OVD cushion that separates the capsule–IOL complex from the anterior hyaloid until it reaches the capsule periphery, just inside the CTR. Then, 1 of the long straight needles of a double-armed 10-0 Prolene suture (Ethicon STC-6) would be inserted through the opposite paracentesis and fed into the needle opening, penetrating the fused capsule leaves just inside the CTR. As the hypodermic needle was retracted, the suture needle would be brought out of the globe. Then, the globe would be penetrated again about 2.0 mm lateral to the primary site, with the needle tip guided in front of the CTR. The second needle of the double-armed Prolene suture would then be inserted through the paracentesis and fed into the needle opening to again be delivered out of the eye. The 2 needles would be removed from the suture ends, but the ends would not yet be knotted. Before the ends were knotted, the cohesive OVD would be carefully aspirated through the paracentesis using a manual dry aspiration technique while the eye is intermittently repressurized with balanced salt solution (BSS). The viscoadhesive cushion at the dialysis area would be left untouched and would not inadvertently follow the aspiration flow due to its lack of cohesiveness. No attempt would be made to completely remove the cohesive OVD. After the bulk of the OVD was aspirated, the anterior chamber would be carefully rinsed with BSS to further reduce the residual amount without jeopardizing the hyaloid surface at the site of dialysis. The paracentesis would be sealed by stromal hydration. Only then (ie, with the OVD removed and the globe pressurized) would the Prolene sutures be knotted outside the eye and their tension carefully adjusted until the capsule–IOL diaphragm was perfectly centered. Then, the suture loop would be rotated until the knot was buried in the eye. An intracameral miotic such as Miochol (acetylcholine chloride) would be injected through the paracentesis to constrict the pupil, and a bolus of cefuroxime would be given for antibiosis. I recommend using pressure-lowering drops and postoperative pressure monitoring to detect and treat a possible pressure peak. Should the residual zonule provide insufficient support on surgical exploration, I would switch to IOL exchange. Two options could be considered. The first is a temporal approach, in which the IOL optic, CTR, and capsular bag would be cut in half for removal
J CATARACT REFRACT SURG - VOL 34, FEBRUARY 2008
188
CONSULTATION SECTION
through a 3.5 mm limbal incision and implantation of a foldable IOL, to be sutured in the sulcus. The second is a superior approach, in which the entire capsule– IOL diaphragm would be removed flat through a 5.8 mm incision and an iris-fixated anterior chamber poly(methyl methacrylate) (PMMA) IOL (Artisan, Ophtec) implanted. I prefer the latter approach as cutting and removing the CTR and IOL within the fused capsules through a small incision requires more intraocular manipulation with a greater risk for vitreous involvement. In contrast, explantation of the unfolded bulk through the wider incision required for implantation of the PMMA IOL is easier, fixation of the IOL to the iris is simple and perfectly controlled, and endothelial problems with this IOL will not occur in a deep aphakic chamber. Rupert Menapace, MD Vienna, Austria REFERENCE 1. Duffey RJ, Holland EJ, Agapitos PJ, Lindstrom RL. Anatomic study of transsclerally sutured intraocular lens implantation. Am J Ophthalmol 1989; 108:300–309
- In this case of a subluxated 1-piece acrylic posterior chamber IOL–CTR–capsular bag complex without vitreous prolapse, surgical management should proceed as our experience has been that progressive decentration with ultimate dislocation is likely to occur in these circumstances. Management of the PCO should be deferred until after surgical management of the subluxation. The first surgical decision is to determine whether IOL repositioning or IOL exchange is indicated. Considering the advantages of smaller incisions, minimal invasiveness, reduction in intraoperative manipulation and trauma, and the reduced likelihood of vitreous prolapse and/or the need for vitrectomy, our preference is to proceed with IOL suture repositioning as opposed to exchange. The next surgical decision is to determine the appropriate repositioning strategy. Although helpful for other IOL designs and circumstances, removal of the IOL from the capsular bag and fixation to the iris would not be appropriate here considering the potential technical difficulties in suturing the flexible haptics to the posterior iris and the postoperative risk for pigment dispersion from the bulky acrylic haptics and planar optic design. Thus, our preference would be an ab externo scleral suture fixation method to loop and recenter the IOL– CTR–capsular bag complex, as we have described.1,2 Briefly, a short 26-gauge hypodermic needle is placed
Figure 2. Scleral suturing of dislocated IOL–CTR–capsular bag complex. A 9-0 polypropylene suture needle passed through a paracentesis (left) is docked in a 26-gauge short hypodermic needle (right) passed through sclera 1.5 mm posterior to the limbus. The 26-gauge needle has passed beneath the CTR, through the fused posterior and anterior capsule leaflets, and into the anterior chamber. The docked 9-0 polypropylene suture and 26-gauge needle are then retracted from the eye through the scleral entry point.
through a scleral groove 1.5 mm posterior to the limbus. The first pass is placed under the CTR, through both leaflets of the fused anterior and posterior capsules and into the anterior chamber, where 1 end of a double-armed 9-0 polypropylene suture (Ethicon) is docked into the 26-gauge needle, which is then pulled back out through the scleral groove (Figure 2). A similar second pass is made adjacent to the first pass, but anterior to the CTR and capsule. This results in a suture loop around the CTR that, when tightened and knotted externally, will reposition the capsular bag complex. The polypropylene knot is ultimately rotated into the sclera to prevent extrusion. Scleral fixation should be performed in the area of zonular dehiscencedin this case, superotemporally. A single fixation point may be sufficient; however, intraoperative assessment of overall support should be ascertained before this decision is made. In these circumstances, the presence of a CTR as the backbone of the capsular bag often provides adequate centration and support when 1 suture is placed in the area of greatest zonular weakness, particularly when it is placed superiorly. If necessary, a second, and sometimes third point of fixation may be placed to support the entire complex. Although suture fixation of each haptic in cases of in-the-bag posterior chamber IOL subluxation is an effective method,2 2-point fixation, 180 degrees apart, of a CTR in the capsular bag carries an increased risk for tilt. Thus, if necessary, 3-point fixation to the sclera, each placed 120 degrees from each other, is preferred in cases of profound zonular instability in the presence of a CTR in the bag.
J CATARACT REFRACT SURG - VOL 34, FEBRUARY 2008