Surgical Technique
Edited by George A. Williams
Sutureless Scleral Tunnel Intraocular Lens Fixation in the Pediatric Population
M
rate, but no reports of this technique being performed in pediatric patients have been reported to date. We describe slight modifications to this surgical technique as it pertains to pediatric patients (,18 years of age) who are aphakic and without sufficient capsular support for traditional sulcus placement of a secondary IOL. We present here our single surgeon (M.K.W.) case series using this novel technique in 10 eyes of 7 children with a variety of pediatric lenticular disorders. Through this technique, we have been able to achieve reliable and reproducible results without any cases of postoperative IOL subluxation, dislocation, decentration, iris capture, postoperative retinal detachment, corneal decompensation, endophthalmitis, or cystoid macular edema (Table 1). Additionally, we describe a unique case where a piggyback secondary SST-IOL lens implantation was performed.
any pediatric eye diseases require the removal of the native crystalline lens including congenital cataracts, subluxed or dislocated lenses in Marfan syndrome, retrolental fibrovascular tissue in persistent fetal vasculature, or retinopathy of prematurity, etc. Depending on the age of the patient, options for optical correction include leaving the patient aphakic with possible spectacle or contact lens correction and primary or later secondary intraocular lens (IOL) implantation. There is an increasing trend toward IOL implantation in children given presumed better visual outcomes.1 Intraocular lens placement in the pediatric population is especially challenging in the setting of insufficient capsular support precluding in the capsular bag or ciliary sulcus IOL implantation. Historically, these children have largely been left aphakic and require long-term aphakic spectacle or contact lens wear. Unlike in adults who have insufficient capsular support, anterior chamber IOLs have typically been avoided in children because of their smaller anterior chambers and presumed increased risk of corneal decompensation secondary to endothelial damage that may ensue over the lifetime of the patient. Additionally, both iris and scleral suture fixated techniques for secondary IOL implantation in the setting of insufficient capsular support have the disadvantage that their sutures tend to degrade and break over time with subsequent IOL dislocation,3–5 and thus these techniques are rarely used in children. A newer technique recently described in adults by Prenner et al6 involving sutureless scleral tunnel intraocular lens (SST-IOL) fixation in the ciliary sulcus seems to mitigate this problem. This technique has recently gained popularity in adults because of its high success rate and low complication
Surgical Technique The Supplemental Digital Content 1 (see Video; http://links.lww.com/IAE/A216) demonstrates the key steps of this procedure in a 14-month-old child (Patient 1 in Table 1) with a history of congenital aniridia and congenital cataracts in both eyes status and cataract extraction elsewhere followed by secondary IOL implantation in the sulcus elsewhere in the right eye. The IOL dislocated because of insufficient capsular support, at which point he was referred to one of the authors (M.K.W.) who performed the SST-IOL technique to fixate the dislocated 3-piece IOL into the ciliary sulcus. The Supplemental Digital Content 2 (see Video; http://links.lww.com/IAE/A217) shows the surgery of Patient 3 (Table 1). At 3 months of age, one of the authors (M.K.W.) performed a limbalbased lensectomy and vitrectomy for combined anterior and posterior persistent fetal vasculature syndrome associated with epipapillary traction retinal detachment. His traction retinal detachment resolved, but he did not tolerate contact lens wear, therefore a secondary IOL was placed in SST-IOL fashion at 2 years of age. A conjunctival peritomy is first created inferiorly and superiorly at the limbus. Diathermy is avoided to decrease the risk of subsequent scleromalacia. Then
From the *Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona; and †Retina Associates Southwest, Tucson, Arizona. None of the authors have any financial/conflicting interests to disclose. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.retinajournal.com). Reprint requests: Mark K. Walsh, MD, PhD, Retina Associates Southwest, 6561 E. Carondelet Drive, Tucson, AZ 85710; e-mail: [email protected]
807
808
Patient
Age at Surgery, years
Eye OD · 2 (piggyback)
1
1 (first procedure) and 3 (second procedure)
2
16
OD
3
2
OS
4 5
17 10
OD OU
6
14
OS
7
8
OU
RRD, rhegmatogenous retinal detachment.
Original Diagnosis Aniridia with congenital cataracts s/p cataract extraction OU and secondary posterior chamber IOL implantation OD elsewhere, then dislocated IOL OD. SST-IOL of dislocated IOL resulted in residual 8 D of hyperopia, therefore second IOL (3-piece silicone) placed in piggyback SST-IOL fashion Uveitis–glaucoma–hyphema syndrome secondary to subluxed IOL Persistent fetal vasculature syndrome s/p lensectomy and vitrectomy OS at 3 months of age with aphakia and contact lens wear intolerance Marfan syndrome with subluxed lenses OU Marfan syndrome with subluxed lenses OU
Length of Follow-up
Complications
24 months OD, 5 months s/p piggyback IOL
None
11.5 months
None
10 months
None
9 months 7 months OD, 4 months OS 5 months
None None
Congenital cataracts OU with aphakia OU and contact lens intolerance Aniridia with congenital cataracts s/p cataract 3 months OD, extraction with aphakia and contact lens wear intolerance 2 months OS
None OS-intraoperative superior retinal dialysis with limited RRD after capsular fibrosis was peeled from corneal wound; attached postoperatively
RETINA, THE JOURNAL OF RETINAL AND VITREOUS DISEASES 2014 VOLUME 34 NUMBER 4
Table 1. Lists the Cases of SST-IOL Fixation Performed by the First Author (M.K.W.) Along With a Short Description and Length of Follow-up
SURGICAL TECHNIQUE
2 mm to 3 mm (depending on the patient age) posterior to the inferotemporal or inferonasal limbus, a 25-gauge (G) valved cannula is placed with a trochar in a perpendicular fashion for the infusion line; we use the Alcon Constellation (Fort Worth, TX) vitrectomy system. Two additional 25 G cannulae are placed in a similar fashion superotemporally and superonasally. In phakic eyes, as in Marfan syndrome with subluxed lenses, a standard 25 G 3-port vitrectomy set-up is used to perform lensectomy using the vitrector with the removal of the entire lens and lens capsule, followed by a core vitrectomy. In aphakic eyes, a limited core vitrectomy is performed. Then, 12and 6-o’clock positions are marked with an 8-ray corneal marker at the limbus. At 1.5-mm posterior to the limbus at 12- and 6-o’clock, a 20 G microvitreoretinal blade is used to make sclerotomies that are limbus parallel in the area of the ciliary sulcus. These ciliary sulcus-based sclerotomies are then enlarged to approximately double the width of the 20 G blade. They are enlarged to enhance visualization of the haptics to facilitate placement of the IOL haptics in the scleral tunnels later in the procedure. A 23 G microvitreoretinal blade is then used to create 2 partial-thickness scleral tunnels (50%) emanating from the sclerotomies and 3 mm in length with the distal end (farthest from the sclerotomy) of the tunnel biased 0.5 mm toward the limbus. Initially, the author made these tunnels parallel to the limbus but has found that angling these tunnels with the distal end of the tunnel closer to the limbus than the proximal end results in a more natural position for the IOL haptics. This subsequently results in less IOL manipulation intraoperatively and helps to prevent IOL tilt or decentration. The tunnel extends nasally from the superior 12-o’clock sclerotomy and temporally from the inferior 6-o’clock sclerotomy in the left eye and vice versa for the right eye. Paracenteses are then created with a 15° blade temporally and superonasally at the limbus, and viscoelastic is injected into the anterior chamber to protect the corneal endothelium. Then, a 3-mm beveled clear corneal incision is made at 11-o’clock with a 3-mm keratome with subsequent injection of a 3-piece IOL into the anterior chamber. The Alcon MA50BM IOL is preferred because it has a large 6.5-mm acrylic optic and flexible polymethylmethacrylate haptics with an overall diameter of 13 mm, including the haptics. The leading inferior haptic is usually inserted posterior to the iris and the trailing haptic is kept outside the eye. Alternatively, the entire IOL can be placed in the anterior chamber. Disposable 25 G forceps (Zuidland, The Netherlands) are then used to directly grab the tip of the inferior haptic through the 6-o’clock sclerotomy to externalize it; historically, we used the Eckhardt 25 G
809
end-grasping forceps (Dutch Ophthalmic, DORC, Zuidland, The Netherlands), but most styles of 25 G retinal forceps should work. Recent experience with the DORC Scharioth 25 G forceps, which were specifically designed for use in SST-IOL fixation procedures, has made the process of placing the haptics in the scleral tunnels even easier. The superior trailing haptic is then placed into the anterior chamber using McPherson (Bausch & Lomb, Bridgewater, NJ) forceps. Using 25 G Eckhardt forceps through the temporal paracentesis and another 25 G Eckhardt forceps through the 12o’clock sclerotomy, a handshake technique is used to grasp the haptic with 1 pair of forceps and hand it to the other pair of forceps. Care is taken to grasp the ends of the haptics when externalizing them through the ciliary sulcus-based sclerotomies to decrease the risk of haptic breakage. The same 25 G forceps are then used to grasp and then push one of the haptics through the scleral tunnel while pulling the other haptic through the opposite scleral tunnel. One haptic is always pushed and the other is pulled so that the forceps can approach the tunnel from the patient’s temporal side, allowing the forceps to engage the haptic parallel to the ground, avoiding interference from the patient’s nose and obviating the need to bend the forceps. The haptics are then readjusted in the tunnels, if need be, to obtain a flat and centered IOL position. If the IOL is found to be somewhat tilted on its vertical axis, it may rarely be necessary to create another tunnel in a different angle to remove the IOL tilt. Once the IOL is in the desired position, if the tips of the haptics extrude from the ends of the scleral tunnels, they can be trimmed with Vannas scissors. The vitrector is then placed into the anterior chamber through the paracentesis to remove the viscoelastic followed by stromal hydration of the paracentesis and placement of a 10-0 nylon in the clear corneal wound. Acetylcholine chloride intraocular solution (Miochol-E, Novartis, East Hanover, NJ) is then injected into the anterior chamber to create miosis and we avoid dilating the patient on postoperative Day 1. A 7-0 absorbable polyglactin suture is used to close the ciliary sulcus-based sclerotomies. In children, after removing the 25 G cannulae, the sclerotomies are also closed with 7-0 suture while the conjunctiva is closed with 6-0 plain gut suture. In the operating author’s experience, there have been 2 postoperative IOL subluxations of over 40 SST-IOL cases performed, both in adult patients (data not presented). Both these subluxations occurred within 2 weeks of the initial surgery, and both involved rescuing a dislocated 3-piece IOL. The subluxations may have been related to the different haptic design, material, or dimensions of the rescued IOLs relative to the preferred Alcon MA50BM IOL. However, given that both subluxations occurred early,
810
RETINA, THE JOURNAL OF RETINAL AND VITREOUS DISEASES 2014 VOLUME 34 NUMBER 4
the author now places a 7-0 absorbable polyglactin suture around each scleral tunnel and haptic to secure them in place temporarily to allow the scleral tunnels time to heal and fibrose before the sutures dissolve. In cases of subluxed or dislocated IOLs, if the IOL is a 1-piece acrylic IOL, it is cut in half (or cut 95% of the way through the horizontal meridian) with an IOL cutting scissor just posterior to the iris plane and then removed from the eye either through an enlarged temporal sclerotomy or a clear corneal wound. If the IOL is a one-piece polymethylmethacrylate IOL, it is removed through the anterior chamber through a scleral tunnel. If the IOL is a 3-piece, then an attempt is made to refixate that IOL in sutureless scleral tunnel fashion. If the IOL is in the capsular bag, the IOL optic is grasped in one hand with the 25 G Eckhardt forceps and held just posterior to the iris plane while using another 25 G forceps and the vitrector to carefully remove all of the capsule from the IOL and haptics under direct visualization. Care is taken not to damage the haptics. If the IOL or haptics are damaged, then it is cut in half and removed similar to the one-piece acrylic IOL. The rest of the procedure is as outlined above. The senior author performed this SST-IOL technique for the first time (in an adult or child) in Patient 1 (see Video, Supplemental Digital Content 1; http://links.lww.com/IAE/A216). In Patient 1, an outside surgeon placed a 28.5-diopter (D) Alcon MA60AC at 11 months of age in the right eye. That IOL dislocated posteriorly because of insufficient capsular support, which was then refixated in SST-IOL fashion. He subsequently had a Baerveldt (Abbott Medical Optics, Abbott Park, IL) tube shunt placed in the right eye a few months later by a pediatric glaucoma specialist. At 19 months of age, the senior author placed an IOL in the left eye in a traditional fashion in the sulcus because there was sufficient capsular support. He then had multiple examinations under anesthesia by both referring pediatric ophthalmologist and pediatric glaucoma specialist who revealed that he was 8.5 D more hyperopic in the right eye compared with the left eye, presumably because of an underpowered initial IOL implant in the right eye because the patient’s axial length was only 13.28 mm. The examinations under anesthesia showed the right eye to be +10.50 D and the left eye to be +2.00 D. An attempt at contact lens wear was unsuccessful. Given the risk of anisometropic amblyopia, a second 3-piece IOL was placed in the right eye as a piggyback lens in SST-IOL fashion (see Video, Supplemental Digital Content 3; http://links.lww.com/IAE/A218). A silicone IOL (Bausch & Lomb LI61AO, Bridgewater, NJ) was used to decrease IOL interface opacification or fibrosis risk. The same technique as outlined above was used except that the ciliary sulcus-based sclerotomies were
placed at 3- and 9-o’ clock and were made 1 mm, not 1.5 mm, from the limbus. This is the first report of SSTIOL placed in piggyback fashion to our knowledge.
Discussion Sutureless scleral tunnel intraocular lens fixation was first described by Scharioth et al.7 Agarwal et al8 then modified the technique using scleral flaps and fibrin glue. Prenner et al6 then developed a similar technique using posterior segment instrumentation and skills. All three techniques seem to decrease the risk of complications traditionally associated with suture-fixated or anterior chamber IOLs (e.g., IOL dislocation, decentration, or tilt, corneal decompensation, cystoid macular edema, pseudophacodonesis, and suture exposure with endophthalmitis). Given the theoretical advantages of this technique over traditional IOL fixation techniques in the setting of insufficient capsular support, we thought that it was particularly suited to pediatric patients in whom the chances of suture breakage with IOL dislocation and corneal decompensation, in particular over the lifetime of the patient, are likely higher than in an adult patient. Here, we have described slight modifications to the technique by Prenner et al and to our outcomes to date in pediatric patients. Of the 10 SST-IOL cases performed in children, 5 of them have been followed for 6 months or more. There have been no complications related to the actual SST-IOL fixation procedure (i.e., IOL dislocation, subluxation, tilt, haptic extrusion, cystoid macular edema, corneal decompensation, and endophthalmitis). Of note, there was one patient with aphakia after congenital cataract removal who was noted to have capsular fibrosis/scar tissue incarcerated in the corneal wound extending to the superior anterior chamber angle intraoperatively. When this was peeled away, the patient developed a superior retinal dialysis with limited rhegmatogenous retinal detachment, presumably, because the scar tissue extended posteriorly into the vitreous base. This limited detachment was repaired intraoperatively using laser retinopexy and air tamponade, and the patient’s retina has remained attached in follow-up. Although this technique has clear theoretical advantages over suture fixation of IOLs or anterior chamber IOLs in children, we have no data on the long-term outcomes of this SST-IOL technique in children. However, our experience to date has been encouraging because this technique has given us a tool to help those aphakic children with insufficient capsular support who are monocularly aphakic but contact lens intolerant, and thus are at high risk for unilateral amblyopia. We have
SURGICAL TECHNIQUE
also been able to help those children who are bilaterally aphakic but contact lens intolerant. These patients have been burdened with cumbersome aphakic spectacles that limit their visual field and create a less than ideal image because of image distortion and prismatic effects, leading to bilateral amblyopia and limited visual development.9 Key words: sutureless, scleral tunnel fixation, intraocular lens, piggyback, aniridia, pediatric cataracts, Marfan syndrome. MARK K. WALSH, MD, PHD*† MALAV JOSHI, MD* References 1. Al Shamrani M, Al Turkmani S. Update of intraocular lens implantation in children. Saudi J Ophthalmol 2012;26:271–275. 2. Wilson ME, Bartholomew LR, Trivedi RH. Pediatric cataract surgery and intraocular lens implantation: practice styles and preferences of the 2001 ASCRS and AAPOS memberships. J Cataract Refract Surg 2003;29:1811–1820.
811
3. McAllister AS, Hirst LW. Visual outcomes and complications of scleral-fixated posterior chamber intraocular lenses. J Cataract Refract Surg 2011;37:1263–1269. 4. Vote BJ, Tranos P, Bunce C, et al. Long-term outcome of combined pars plana vitrectomy and scleral fixated sutured posterior chamber intraocular lens implantation. Am J Ophthalmol 2006; 141:308–312. 5. Hirashima DE, Soriano ES, Meirelles RL, et al. Outcomes of iris-claw anterior chamber versus iris-fixated foldable intraocular lens in subluxated lens secondary to Marfan syndrome. Ophthalmology 2010;117:1479–1485. 6. Prenner JL, Feiner L, Wheatley HM, Connors D. A novel approach for posterior chamber intraocular lens placement or rescue via a sutureless scleral fixation technique. Retina 2012; 32:853–855. 7. Sharioth GB, Prasad S, Georgalas I, et al. Intermediate results of sutureless intrascleral posterior chamber intraocular lens fixation. J Cataract Refract Surg 2010;36:254–259. 8. Agarwal A, Kumar DA, Jacob S, et al. Fibrin glue-assisted sutureless posterior chamber intraocular lens implantation in eyes with deficient posterior capsules. J Cataract Refract Surg 2008;34:1433–1438. 9. Terri LL, Maurer D, Brent HP. Development of grating acuity in children treated for unilateral or bilateral congenital cataract. Invest Ophthalmol Vis Sci 1995;36:2080–2095.
Edited by George A. Williams
Sutureless Scleral Tunnel Intraocular Lens Fixation in the Pediatric Population
M
rate, but no reports of this technique being performed in pediatric patients have been reported to date. We describe slight modifications to this surgical technique as it pertains to pediatric patients (,18 years of age) who are aphakic and without sufficient capsular support for traditional sulcus placement of a secondary IOL. We present here our single surgeon (M.K.W.) case series using this novel technique in 10 eyes of 7 children with a variety of pediatric lenticular disorders. Through this technique, we have been able to achieve reliable and reproducible results without any cases of postoperative IOL subluxation, dislocation, decentration, iris capture, postoperative retinal detachment, corneal decompensation, endophthalmitis, or cystoid macular edema (Table 1). Additionally, we describe a unique case where a piggyback secondary SST-IOL lens implantation was performed.
any pediatric eye diseases require the removal of the native crystalline lens including congenital cataracts, subluxed or dislocated lenses in Marfan syndrome, retrolental fibrovascular tissue in persistent fetal vasculature, or retinopathy of prematurity, etc. Depending on the age of the patient, options for optical correction include leaving the patient aphakic with possible spectacle or contact lens correction and primary or later secondary intraocular lens (IOL) implantation. There is an increasing trend toward IOL implantation in children given presumed better visual outcomes.1 Intraocular lens placement in the pediatric population is especially challenging in the setting of insufficient capsular support precluding in the capsular bag or ciliary sulcus IOL implantation. Historically, these children have largely been left aphakic and require long-term aphakic spectacle or contact lens wear. Unlike in adults who have insufficient capsular support, anterior chamber IOLs have typically been avoided in children because of their smaller anterior chambers and presumed increased risk of corneal decompensation secondary to endothelial damage that may ensue over the lifetime of the patient. Additionally, both iris and scleral suture fixated techniques for secondary IOL implantation in the setting of insufficient capsular support have the disadvantage that their sutures tend to degrade and break over time with subsequent IOL dislocation,3–5 and thus these techniques are rarely used in children. A newer technique recently described in adults by Prenner et al6 involving sutureless scleral tunnel intraocular lens (SST-IOL) fixation in the ciliary sulcus seems to mitigate this problem. This technique has recently gained popularity in adults because of its high success rate and low complication
Surgical Technique The Supplemental Digital Content 1 (see Video; http://links.lww.com/IAE/A216) demonstrates the key steps of this procedure in a 14-month-old child (Patient 1 in Table 1) with a history of congenital aniridia and congenital cataracts in both eyes status and cataract extraction elsewhere followed by secondary IOL implantation in the sulcus elsewhere in the right eye. The IOL dislocated because of insufficient capsular support, at which point he was referred to one of the authors (M.K.W.) who performed the SST-IOL technique to fixate the dislocated 3-piece IOL into the ciliary sulcus. The Supplemental Digital Content 2 (see Video; http://links.lww.com/IAE/A217) shows the surgery of Patient 3 (Table 1). At 3 months of age, one of the authors (M.K.W.) performed a limbalbased lensectomy and vitrectomy for combined anterior and posterior persistent fetal vasculature syndrome associated with epipapillary traction retinal detachment. His traction retinal detachment resolved, but he did not tolerate contact lens wear, therefore a secondary IOL was placed in SST-IOL fashion at 2 years of age. A conjunctival peritomy is first created inferiorly and superiorly at the limbus. Diathermy is avoided to decrease the risk of subsequent scleromalacia. Then
From the *Department of Ophthalmology and Vision Science, University of Arizona, Tucson, Arizona; and †Retina Associates Southwest, Tucson, Arizona. None of the authors have any financial/conflicting interests to disclose. Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.retinajournal.com). Reprint requests: Mark K. Walsh, MD, PhD, Retina Associates Southwest, 6561 E. Carondelet Drive, Tucson, AZ 85710; e-mail: [email protected]
807
808
Patient
Age at Surgery, years
Eye OD · 2 (piggyback)
1
1 (first procedure) and 3 (second procedure)
2
16
OD
3
2
OS
4 5
17 10
OD OU
6
14
OS
7
8
OU
RRD, rhegmatogenous retinal detachment.
Original Diagnosis Aniridia with congenital cataracts s/p cataract extraction OU and secondary posterior chamber IOL implantation OD elsewhere, then dislocated IOL OD. SST-IOL of dislocated IOL resulted in residual 8 D of hyperopia, therefore second IOL (3-piece silicone) placed in piggyback SST-IOL fashion Uveitis–glaucoma–hyphema syndrome secondary to subluxed IOL Persistent fetal vasculature syndrome s/p lensectomy and vitrectomy OS at 3 months of age with aphakia and contact lens wear intolerance Marfan syndrome with subluxed lenses OU Marfan syndrome with subluxed lenses OU
Length of Follow-up
Complications
24 months OD, 5 months s/p piggyback IOL
None
11.5 months
None
10 months
None
9 months 7 months OD, 4 months OS 5 months
None None
Congenital cataracts OU with aphakia OU and contact lens intolerance Aniridia with congenital cataracts s/p cataract 3 months OD, extraction with aphakia and contact lens wear intolerance 2 months OS
None OS-intraoperative superior retinal dialysis with limited RRD after capsular fibrosis was peeled from corneal wound; attached postoperatively
RETINA, THE JOURNAL OF RETINAL AND VITREOUS DISEASES 2014 VOLUME 34 NUMBER 4
Table 1. Lists the Cases of SST-IOL Fixation Performed by the First Author (M.K.W.) Along With a Short Description and Length of Follow-up
SURGICAL TECHNIQUE
2 mm to 3 mm (depending on the patient age) posterior to the inferotemporal or inferonasal limbus, a 25-gauge (G) valved cannula is placed with a trochar in a perpendicular fashion for the infusion line; we use the Alcon Constellation (Fort Worth, TX) vitrectomy system. Two additional 25 G cannulae are placed in a similar fashion superotemporally and superonasally. In phakic eyes, as in Marfan syndrome with subluxed lenses, a standard 25 G 3-port vitrectomy set-up is used to perform lensectomy using the vitrector with the removal of the entire lens and lens capsule, followed by a core vitrectomy. In aphakic eyes, a limited core vitrectomy is performed. Then, 12and 6-o’clock positions are marked with an 8-ray corneal marker at the limbus. At 1.5-mm posterior to the limbus at 12- and 6-o’clock, a 20 G microvitreoretinal blade is used to make sclerotomies that are limbus parallel in the area of the ciliary sulcus. These ciliary sulcus-based sclerotomies are then enlarged to approximately double the width of the 20 G blade. They are enlarged to enhance visualization of the haptics to facilitate placement of the IOL haptics in the scleral tunnels later in the procedure. A 23 G microvitreoretinal blade is then used to create 2 partial-thickness scleral tunnels (50%) emanating from the sclerotomies and 3 mm in length with the distal end (farthest from the sclerotomy) of the tunnel biased 0.5 mm toward the limbus. Initially, the author made these tunnels parallel to the limbus but has found that angling these tunnels with the distal end of the tunnel closer to the limbus than the proximal end results in a more natural position for the IOL haptics. This subsequently results in less IOL manipulation intraoperatively and helps to prevent IOL tilt or decentration. The tunnel extends nasally from the superior 12-o’clock sclerotomy and temporally from the inferior 6-o’clock sclerotomy in the left eye and vice versa for the right eye. Paracenteses are then created with a 15° blade temporally and superonasally at the limbus, and viscoelastic is injected into the anterior chamber to protect the corneal endothelium. Then, a 3-mm beveled clear corneal incision is made at 11-o’clock with a 3-mm keratome with subsequent injection of a 3-piece IOL into the anterior chamber. The Alcon MA50BM IOL is preferred because it has a large 6.5-mm acrylic optic and flexible polymethylmethacrylate haptics with an overall diameter of 13 mm, including the haptics. The leading inferior haptic is usually inserted posterior to the iris and the trailing haptic is kept outside the eye. Alternatively, the entire IOL can be placed in the anterior chamber. Disposable 25 G forceps (Zuidland, The Netherlands) are then used to directly grab the tip of the inferior haptic through the 6-o’clock sclerotomy to externalize it; historically, we used the Eckhardt 25 G
809
end-grasping forceps (Dutch Ophthalmic, DORC, Zuidland, The Netherlands), but most styles of 25 G retinal forceps should work. Recent experience with the DORC Scharioth 25 G forceps, which were specifically designed for use in SST-IOL fixation procedures, has made the process of placing the haptics in the scleral tunnels even easier. The superior trailing haptic is then placed into the anterior chamber using McPherson (Bausch & Lomb, Bridgewater, NJ) forceps. Using 25 G Eckhardt forceps through the temporal paracentesis and another 25 G Eckhardt forceps through the 12o’clock sclerotomy, a handshake technique is used to grasp the haptic with 1 pair of forceps and hand it to the other pair of forceps. Care is taken to grasp the ends of the haptics when externalizing them through the ciliary sulcus-based sclerotomies to decrease the risk of haptic breakage. The same 25 G forceps are then used to grasp and then push one of the haptics through the scleral tunnel while pulling the other haptic through the opposite scleral tunnel. One haptic is always pushed and the other is pulled so that the forceps can approach the tunnel from the patient’s temporal side, allowing the forceps to engage the haptic parallel to the ground, avoiding interference from the patient’s nose and obviating the need to bend the forceps. The haptics are then readjusted in the tunnels, if need be, to obtain a flat and centered IOL position. If the IOL is found to be somewhat tilted on its vertical axis, it may rarely be necessary to create another tunnel in a different angle to remove the IOL tilt. Once the IOL is in the desired position, if the tips of the haptics extrude from the ends of the scleral tunnels, they can be trimmed with Vannas scissors. The vitrector is then placed into the anterior chamber through the paracentesis to remove the viscoelastic followed by stromal hydration of the paracentesis and placement of a 10-0 nylon in the clear corneal wound. Acetylcholine chloride intraocular solution (Miochol-E, Novartis, East Hanover, NJ) is then injected into the anterior chamber to create miosis and we avoid dilating the patient on postoperative Day 1. A 7-0 absorbable polyglactin suture is used to close the ciliary sulcus-based sclerotomies. In children, after removing the 25 G cannulae, the sclerotomies are also closed with 7-0 suture while the conjunctiva is closed with 6-0 plain gut suture. In the operating author’s experience, there have been 2 postoperative IOL subluxations of over 40 SST-IOL cases performed, both in adult patients (data not presented). Both these subluxations occurred within 2 weeks of the initial surgery, and both involved rescuing a dislocated 3-piece IOL. The subluxations may have been related to the different haptic design, material, or dimensions of the rescued IOLs relative to the preferred Alcon MA50BM IOL. However, given that both subluxations occurred early,
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RETINA, THE JOURNAL OF RETINAL AND VITREOUS DISEASES 2014 VOLUME 34 NUMBER 4
the author now places a 7-0 absorbable polyglactin suture around each scleral tunnel and haptic to secure them in place temporarily to allow the scleral tunnels time to heal and fibrose before the sutures dissolve. In cases of subluxed or dislocated IOLs, if the IOL is a 1-piece acrylic IOL, it is cut in half (or cut 95% of the way through the horizontal meridian) with an IOL cutting scissor just posterior to the iris plane and then removed from the eye either through an enlarged temporal sclerotomy or a clear corneal wound. If the IOL is a one-piece polymethylmethacrylate IOL, it is removed through the anterior chamber through a scleral tunnel. If the IOL is a 3-piece, then an attempt is made to refixate that IOL in sutureless scleral tunnel fashion. If the IOL is in the capsular bag, the IOL optic is grasped in one hand with the 25 G Eckhardt forceps and held just posterior to the iris plane while using another 25 G forceps and the vitrector to carefully remove all of the capsule from the IOL and haptics under direct visualization. Care is taken not to damage the haptics. If the IOL or haptics are damaged, then it is cut in half and removed similar to the one-piece acrylic IOL. The rest of the procedure is as outlined above. The senior author performed this SST-IOL technique for the first time (in an adult or child) in Patient 1 (see Video, Supplemental Digital Content 1; http://links.lww.com/IAE/A216). In Patient 1, an outside surgeon placed a 28.5-diopter (D) Alcon MA60AC at 11 months of age in the right eye. That IOL dislocated posteriorly because of insufficient capsular support, which was then refixated in SST-IOL fashion. He subsequently had a Baerveldt (Abbott Medical Optics, Abbott Park, IL) tube shunt placed in the right eye a few months later by a pediatric glaucoma specialist. At 19 months of age, the senior author placed an IOL in the left eye in a traditional fashion in the sulcus because there was sufficient capsular support. He then had multiple examinations under anesthesia by both referring pediatric ophthalmologist and pediatric glaucoma specialist who revealed that he was 8.5 D more hyperopic in the right eye compared with the left eye, presumably because of an underpowered initial IOL implant in the right eye because the patient’s axial length was only 13.28 mm. The examinations under anesthesia showed the right eye to be +10.50 D and the left eye to be +2.00 D. An attempt at contact lens wear was unsuccessful. Given the risk of anisometropic amblyopia, a second 3-piece IOL was placed in the right eye as a piggyback lens in SST-IOL fashion (see Video, Supplemental Digital Content 3; http://links.lww.com/IAE/A218). A silicone IOL (Bausch & Lomb LI61AO, Bridgewater, NJ) was used to decrease IOL interface opacification or fibrosis risk. The same technique as outlined above was used except that the ciliary sulcus-based sclerotomies were
placed at 3- and 9-o’ clock and were made 1 mm, not 1.5 mm, from the limbus. This is the first report of SSTIOL placed in piggyback fashion to our knowledge.
Discussion Sutureless scleral tunnel intraocular lens fixation was first described by Scharioth et al.7 Agarwal et al8 then modified the technique using scleral flaps and fibrin glue. Prenner et al6 then developed a similar technique using posterior segment instrumentation and skills. All three techniques seem to decrease the risk of complications traditionally associated with suture-fixated or anterior chamber IOLs (e.g., IOL dislocation, decentration, or tilt, corneal decompensation, cystoid macular edema, pseudophacodonesis, and suture exposure with endophthalmitis). Given the theoretical advantages of this technique over traditional IOL fixation techniques in the setting of insufficient capsular support, we thought that it was particularly suited to pediatric patients in whom the chances of suture breakage with IOL dislocation and corneal decompensation, in particular over the lifetime of the patient, are likely higher than in an adult patient. Here, we have described slight modifications to the technique by Prenner et al and to our outcomes to date in pediatric patients. Of the 10 SST-IOL cases performed in children, 5 of them have been followed for 6 months or more. There have been no complications related to the actual SST-IOL fixation procedure (i.e., IOL dislocation, subluxation, tilt, haptic extrusion, cystoid macular edema, corneal decompensation, and endophthalmitis). Of note, there was one patient with aphakia after congenital cataract removal who was noted to have capsular fibrosis/scar tissue incarcerated in the corneal wound extending to the superior anterior chamber angle intraoperatively. When this was peeled away, the patient developed a superior retinal dialysis with limited rhegmatogenous retinal detachment, presumably, because the scar tissue extended posteriorly into the vitreous base. This limited detachment was repaired intraoperatively using laser retinopexy and air tamponade, and the patient’s retina has remained attached in follow-up. Although this technique has clear theoretical advantages over suture fixation of IOLs or anterior chamber IOLs in children, we have no data on the long-term outcomes of this SST-IOL technique in children. However, our experience to date has been encouraging because this technique has given us a tool to help those aphakic children with insufficient capsular support who are monocularly aphakic but contact lens intolerant, and thus are at high risk for unilateral amblyopia. We have
SURGICAL TECHNIQUE
also been able to help those children who are bilaterally aphakic but contact lens intolerant. These patients have been burdened with cumbersome aphakic spectacles that limit their visual field and create a less than ideal image because of image distortion and prismatic effects, leading to bilateral amblyopia and limited visual development.9 Key words: sutureless, scleral tunnel fixation, intraocular lens, piggyback, aniridia, pediatric cataracts, Marfan syndrome. MARK K. WALSH, MD, PHD*† MALAV JOSHI, MD* References 1. Al Shamrani M, Al Turkmani S. Update of intraocular lens implantation in children. Saudi J Ophthalmol 2012;26:271–275. 2. Wilson ME, Bartholomew LR, Trivedi RH. Pediatric cataract surgery and intraocular lens implantation: practice styles and preferences of the 2001 ASCRS and AAPOS memberships. J Cataract Refract Surg 2003;29:1811–1820.
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3. McAllister AS, Hirst LW. Visual outcomes and complications of scleral-fixated posterior chamber intraocular lenses. J Cataract Refract Surg 2011;37:1263–1269. 4. Vote BJ, Tranos P, Bunce C, et al. Long-term outcome of combined pars plana vitrectomy and scleral fixated sutured posterior chamber intraocular lens implantation. Am J Ophthalmol 2006; 141:308–312. 5. Hirashima DE, Soriano ES, Meirelles RL, et al. Outcomes of iris-claw anterior chamber versus iris-fixated foldable intraocular lens in subluxated lens secondary to Marfan syndrome. Ophthalmology 2010;117:1479–1485. 6. Prenner JL, Feiner L, Wheatley HM, Connors D. A novel approach for posterior chamber intraocular lens placement or rescue via a sutureless scleral fixation technique. Retina 2012; 32:853–855. 7. Sharioth GB, Prasad S, Georgalas I, et al. Intermediate results of sutureless intrascleral posterior chamber intraocular lens fixation. J Cataract Refract Surg 2010;36:254–259. 8. Agarwal A, Kumar DA, Jacob S, et al. Fibrin glue-assisted sutureless posterior chamber intraocular lens implantation in eyes with deficient posterior capsules. J Cataract Refract Surg 2008;34:1433–1438. 9. Terri LL, Maurer D, Brent HP. Development of grating acuity in children treated for unilateral or bilateral congenital cataract. Invest Ophthalmol Vis Sci 1995;36:2080–2095.
