November consultation #6

November consultation #6

1784 CONSULTATION SECTION capsule. The suture is externalized through the 27gauge needle to create a ring suture around the haptic–endocapsular ring...

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1784

CONSULTATION SECTION

capsule. The suture is externalized through the 27gauge needle to create a ring suture around the haptic–endocapsular ring. The knot is buried in the scleral tissue; therefore, there is no need for a scleral flap. The same is performed on the opposite side because the wobbling motion of the IOL indicates that all the zonular fibers are weakened, not only the inferonasal ones. If needed, a third or more sutures can be placed to maintain a stable central IOL position and prevent IOL tilting. The presence of an endocapsular ring thus turns out to be an advantage because the sutures can be located almost anywhere around the equator (except for the location of the iris shield). I would recommend inserting all sutures before closing the knots to allow controlled, balanced pulling of the sutures and positioning of the capsulorhexis behind the displaced pupil. The entire procedure is performed in a relatively closed system and usually requires only 2 side-port incisions and 4 needle holes. This is a relatively simple and very rewarding procedure, and long-term experience has shown its clinical applicability and efficacy. Ehud I. Assia, MD Kfar-Saba, Israel - This late IOL–capsular bag subluxation due to traumatic zonulopathy is likely to worsen over time because the patient's normal ocular saccades will shear the remaining zonular attachments. Eventually, total posterior dislocation of the IOL–capsular bag complex will occur. Surgical extraction of the entire complex through the pupil would be difficult because of the intracapsular coloboma ring, which is much more rigid and brittle than a conventional CTR. Attempting this would almost certainly necessitate an anterior vitrectomy and would also leave the sector defect unblocked. Therefore, scleral suture fixation of the black intracapsular coloboma ring should be attempted. A variety of techniques are used for scleral suture fixation of an intracapsular CTR. My plan in this case would be to make a half-thickness scleral groove approximately 1.5 mm posterior to the limbus at the desired site for each scleral suture. One scleral suture should be located at the 7 o'clock position in this left eye, at the inferior edge of the large sector defect and alongside the smaller peripheral coloboma. The second scleral suture should be located 180 degrees opposite the first. I would align a quartet of iris retractors so they provide maximum peripheral visualization near these suture sites (1 at the 7 o'clock position and 1 at the 1 o'clock position). Through a paracentesis created over the large defect (8:30 position), I would inject a dispersive OVD behind the IOL–capsular bag complex to

push back the anterior hyaloid face. I would then use a Lester hook to recenter and reposition the coloboma ring so the black plate was realigned with the sector defect. The first scleral suture would be placed at the 7 o'clock position, with the goal of it catching the ring just adjacent to the black plate. A 25-gauge disposable guide needle would be introduced ab externo through the base of the half-thickness scleral groove. The guide needle would be passed through the ciliary sulcus, behind the iris, beneath the CTR, and through the peripheral capsular bag before reaching the pupillary space. Approaching from an oppositely located paracentesis, a straight, doublearmed 9-0 polypropylene suture needle would be docked into the guide-needle lumen so it can be backed out externally through the base of the scleral groove. The same steps would be repeated with the second polypropylene needle, except this time the guide needle would pass above the CTR. The second of the double-armed polypropylene needles would be similarly guided out through the base of the scleral groove so it exits approximately 1.0 mm from the first needle. The smaller peripheral coloboma inferiorly would facilitate visualization of these maneuvers. Once tied, the trimmed knot would lie within the half-thickness scleral groove so it would not erode through the overlying conjunctiva. This same set of steps would be repeated to place the second scleral suture around the CTR at a location 180 degrees away. Figure 3 shows these steps used to scleral suture fixate a CTR after late IOL–capsular bag subluxation in a patient with pseudoexfoliation. David F. Chang, MD Los Altos, California, USA

- The indication for a CTR was correct here because traumatic zonular damage usually leaves a large part of the zonules intact and there is low risk for eventual CTR–IOL complex dislocation. However, now that this has happened, the patient requires further surgery. Because the refractive defect is low and the patient has been satisfied with his IOL, there is no need for IOL exchange. In addition, because vision in supine position is good, we can expect little posterior CTR– IOL displacement at surgery. Therefore, ab externo scleral fixation of the CTR in a closed eye seems to be the best approach.1 General anesthesia would be better because of the length of the procedure, which may last up to

J CATARACT REFRACT SURG - VOL 39, NOVEMBER 2013

CONSULTATION SECTION

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Figure 3. Scleral suture fixation of CTR after late bag–IOL subluxation in a patient with pseudoexfoliation. A: After iris retractors are inserted, a disposable 25-gauge guide needle is introduced ab externo through a half-thickness scleral groove located approximately 1.5 mm behind the limbus. It passes beneath the CTR and through the peripheral capsular bag. B: Approaching from an oppositely placed paracentesis, a straight, double-armed 9-0 polypropylene needle is docked into the guide needle lumen so that it will emerge through the base of the half-thickness scleral groove. C: The same steps are repeated with the second polypropylene needle, except that this time the guide needle passes above the CTR. D: The polypropylene sutures are tied, resulting in scleral fixation and recentering of the IOL–CTR–bag complex. After the suture tips are trimmed, the knot retracts within the base of the half-thickness scleral groove so that it is not exposed.

60 minutes. Two fornix-based conjunctival flaps are prepared from 9 to 12 o'clock and from 2 to 6 o' clock. A 25-gauge irrigating trocar is positioned between 2 and 3 o'clock to be opened at intervals during surgery. Two 3.0 mm  4.0 mm fornix-based scleral flaps are prepared, ideally two thirds of the scleral thickness, and centered at 10 o'clock and 4 o'clock. A 1.0 mm paracentesis is prepared, and a small amount of a cohesive OVD injected into the anterior chamber. Flexible iris retractors are positioned through small paracenteses to enlarge the pupil and increase visualization of the CTR–IOL complex. A 10-0 polypropylene suture attached to a 16.0 mm straight needle is passed through the scleral bed at 10 o'clock 1.0 mm from the limbus, puncturing the peripheral capsule rim from behind anteriorly as close to the CTR as possible. This puncture should be located so the shield would eventually cover the existing iris coloboma. The needle is then passed through the cornea and partially extracted from the eye, with care taken to loosen the polypropylene thread. A side-cutting 27-gauge hollow needle attached to a syringe and bent for better handling is passed near the first needle and advanced between the iris and the CTR–IOL complex. The back

of the 16.0 mm straight needle with the thread attached is inserted in the 27-gauge needle and retracted, thus obtaining a loop of polypropylene around the CTR. The suture is tied and the location of the iris shield controlled. The procedure is repeated at 4 o' clock, and the suture is carefully tied for IOL centration. The iris retractors are removed, and the eye is inspected for the outcome because sometimes 1 of the scleral sutures must be replaced. During the entire procedure, pars plana irrigation is used to control IOP and the CTR–IOL complex position. An OVD is injected at intervals to deepen the anterior chamber and removed by a thin cannula at the end of the procedure. The scleral flaps are sutured with 10-0 polyglactin, and the conjunctiva is closed by gentle diathermy. A small amount of cefuroxime 1.0% is injected into the anterior chamber. Postoperative treatment includes antibiotic and steroid eyedrops and careful control of IOP. Intraoperative bleeding is rare; however, the patient should be informed about a possible prolonged recovery. Roberto Bellucci, MD Verona, Italy

J CATARACT REFRACT SURG - VOL 39, NOVEMBER 2013

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REFERENCE 1. Chung EJ, Kim CY, Koh HJ. Ab externo direct suture technique for dislocated intraocular lens. J Cataract Refract Surg 2007; 33:955–958

- One important thought is that I always, always, operate on the worst-sighted eye first. As a contributor, I was not briefed on the origins and previous surgical discussions regarding this case. The patient had long-standing mild amblyopia with ptosis in his worst-sighted right eye. Even at this late date, I would concentrate my efforts on the right eye first. The patient's best-sighted left eye with the described complication of dislocation had previous surgery. Before tackling the better-sighted left eye, my recommendation would be cataract extraction and repair of the ptosis to get that eye to its best visual performance. Part of this problem might have occurred because the original surgery may have been a little “too fancy.” With my namesake procedure bias1 being extremely partial to iris repair, I would have elected combined cataract surgery with iris dialysis repair. The coloboma would be repaired using my sliding-knot technique. Because primary repair was very possible, extra manipulation occurring with the introduction of additional prosthesis may have stressed the zonule and the capsule. If this were a vibrant 80 year old requiring the best vision possible, I would proceed with removal of the cataract in the amblyopic right eye and ptosis repair. I have often found that the use of an accommodating presbyopia-correcting IOL with custom laser in situ keratomileusis (LASIK) can improve visual performance 2 to 3 lines and might result in a surprisingly functional eye. Oram Kline, my mentor from the early days of IOLs, believed “when in doubt, take it out.” After a complete analysis of the cell count, scanning-slit topography, macular function, and optical coherence tomography, extensive surgery would be considered the “startover” mode. I routinely use the endoscope to assess intraocular structures. With more than 180 degrees of zonulysis, total repair would be recommended. My approach would be to evaluate the zonule. If it were too tenuous, I would create a generous 6.0 mm scleral tunnel incision and prolapse the IOL–capsular complex with an intraocular forceps in an extracapsular fashion. Complete dilation with intracameral epinephrine can be achieved, and mechanical dilation can be added. A generous anterior core vitrectomy with luminary light assistA and a pediatric contact lens would follow. Reinspection with the endoscope under direct visualization would be next. Using the

accommodating IOL in transscleral sulcus fixation mode,B the first mattress suture would be placed in the double-mattress sling technique. After 2 months, LASIK could be performed to obtain maximum visual performance. A more minimal approach would be indicated if the patient had a serious life-limiting situation. Using the CTR as the capsular anchor, I would lean toward various sling or lasso procedures and then introduce a 15.0 mm curved cutting needle with 9-0 polypropylene to stabilize the IOL–capsular bag complex to the sulcus. By repairing the dialysis, the pupil would be recentered. A vitrector could possibly trim up the pupillary aperture to a more physiologic opening. Steven B. Siepser, MD Wayne, Pennsylvania, USA REFERENCE 1. Siepser SB. The closed-chamber slipping suture technique for iris repair. Ann Ophthalmol 1994; 26:71–72

OTHER CITED MATERIAL A. Talsma J, Hirschfeld J, “LASIK light helps surgeon see debris, remove stray fibers,” Ophthalmology Times September 15, 2001, page 29 B. Siepser SB, “New Method of Transscleral Fixation an alternative for securing IOLS,” Ocular Surgery News April 2011, page 85. Available at: http://www.healio.com/ophthalmology/ cataract-surgery/news/print/ocular-surgery-news/%7B2a7544aa9626-4176-8c02-bcb6bf0e2715%7D/new-method-of-transscleralfixation-an-alternative-for-securing-iols. Accessed August 12, 2013

- In this case, traumatic zonular instability and iridodialysis are exacerbated by capsule contraction and the aging process after cataract surgery. The inferotemporal position of the IOL in the erect position suggests that the temporal zonular fibers are still intact, and the improvement in vision in the supine position suggests reasonable anteroposterior stability in the retroiridal position. However, preoperatively the eye should be observed with the patient supine to ascertain the degree of posterior displacement of the IOL, determining the likelihood of the patient requiring vitreoretinal intervention. Surgery is directed toward recentering the corectopic pupil as well as centering and stabilizing the IOL–bag–iris prosthesis complex and occluding the colobomas. The coloboma ring used in this case has a rigid CTR as a backbone, which can be used to stabilize the IOL–capsular bag complex. In the operating theater, 3 scleral grooves are fashioned as follows: peritomies, then 45-degree angled scleral grooves beginning approximately

J CATARACT REFRACT SURG - VOL 39, NOVEMBER 2013