Knowledge of the type of IOL used in the patient’s previous cataract surgery would assist in preoperative surgical planning. When deciding whether to replace or reposition an existing IOL, it is important to remember that a hallmark feature of PXF syndrome is an inherent weakness in the blood–aqueous barrier. In my experience, prolonged IOL–iris contact in the setting of PXF often results in chronic inflammation, elevated IOP, cystoid macular edema, and even uveitis–glaucoma–hyphema syndrome when systemic anticoagulants are used. Pseudoexfoliation is also characterized by poor pupil dilation; therefore, a pupil-expansion device should be used to maximize the pupil diameter during surgery.
If a 1-piece IOL is present in the capsular bag, 2-point scleral fixation of the haptics could be considered.A In the absence of vitreous prolapse, this could be performed with an OVD and an anterior vitrectomy might not be necessary. Severe pigment dispersion is a well-known consequence of outside-the-bag sulcus placement of a 1-piece acrylic IOL. However, chafing between the haptics and the iris is minimized if the haptics are immobilized by fixation to the scleral wall. The bulk of the haptics might also prevent significant tilting of the IOL.
If a 3-piece IOL is present, the IOL–bag complex can be grasped with an MST forceps (Microsurgical Technology) through a side-port incision while the surrounding capsular bag is removed from the IOL with an anterior vitrectomy handpiece, taking care not to damage the haptics. For this procedure, I prefer to place an infusion line through the pars plana using a trocar. If necessary, a complete anterior vitrectomy should be performed using triamcinolone to detect any vitreous in the anterior chamber. After the capsule is removed, the IOL can be fixated to the iris or the sclera. However, I generally avoid iris fixation, considering my previously described concerns of prolonged IOL–iris contact in PXF patients. A 2-point scleral fixation of a 3-piece IOL in the ciliary sulcus might lead to significant IOL tilt. Therefore, I prefer externalizing the haptics through sclerotomies 180 degrees apart and intrascleral fixation of the haptics via a 27-gauge needle track or scleral tunnel, which minimizes movement of the IOL in the sulcus.1
Selective laser trabeculoplasty, placement of multiple trabecular microbypass stents, endoscopic cyclophotocoagulation, and ab interno trabulectomy are all unlikely to lower the IOP sufficiently. Trabeculectomy with MMC would be my first choice, although the recently available micropulse cyclophotocoagulation laser treatment is a tempting alternative. Prolonged inflammation has been reported after micropulse treatment, and repeat treatments might be needed. In the not too distant future, devices such as the XEN implant (Allergan) or Microshunt (Innfocus) might be available as safer alternatives to trabeculectomy for patients such as this.
In terms of management of the left eye, considering the patient’s visual acuity of 20/25 and well-controlled IOP, I would pursue a course of watchful waiting.
In-the-bag subluxation related to exfoliation syndrome is an increasingly common clinical dilemma. Several factors contribute to the dramatic increase in this clinical presentation, including earlier cataract surgery, the aging population with more prolonged pseudophakic status, and the improved capacity for surgeons to successfully complete the original cataract surgery with in-the-bag IOL implantation in patients with exfoliation. Late in-the-bag IOL subluxations generally occur 8 to 10 years after the original surgery. As in this case, increased IOP often occurs coincident with IOL subluxation.
As the invited expert surgeons have nicely outlined, this patient needed a procedure for IOL stabilization as well as IOP reduction. Each of the 7 invited experts provided a reasoned management approach. Trabeculectomy was the most commonly suggested glaucoma procedure, recommended by 5 of the 7 surgeons. Two of the surgeons recommended an aqueous drainage device or tube shunt. The general sentiment was that minimally invasive glaucoma surgery procedures were unlikely to control the IOP in this instance, given the markedly elevated preoperative IOP and poor tolerance of medications.
Most of the surgeons advocated suture fixation of the IOL, using various transscleral or iris-fixation techniques, and they offered several caveats for managing vitreous prolapse and other comorbidities common in such cases. Appropriate caution concerning the propensity for subluxated IOLs to cause pupillary block was rendered; although in my experience puillary block is uncommon with “in-the-bag” subluxation related to exfoliation. Many of the surgeons mentioned that their management might depend on whether the involved IOL was a 1-piece or a 3-piece model, although in my experience the IOL type (3-piece versus 1-piece) is less important when the entire IOL is within the capsular bag. That is, iris- or sulcus-sutured IOLs are less likely to cause iris chafe when the IOL is contained within the bag. This is in direct contrast to sulcus placement of 1-piece IOLs, which is to be discouraged.
The patient in this case presentation was from my practice, and I managed her with trabeculectomy combined with iris-suture fixation of the IOL–capsule complex as described by Dr. Condon in this article. This technique differs from typical iris–IOL suture-fixation strategies in that it involves suturing the capsule complex directly to the iris without passing sutures around the haptics. This patient’s capsule was fibrotic and phimotic, and it was quite amenable to iris fixation, using a McCannel suture technique directly through the fibrotic anterior capsule. Figure 8 shows the 5-week postoperative photographs. My technique is based on the original description by Kirk and Condon.1 One of the benefits of this fixation technique is that there would be minimum tissue disruption. In addition, it helps maintain an intact vitreous face because the entire suture is passed anteriorly to the optic of the IOL. It can also be accomplished without conjunctival manipulation, an obvious advantage when performing coincident trabeculectomy. This approach is most applicable to cases in which there is a fibrotic capsule with moderate phimosis and without large Elschnig pearl formation.
Thomas W. Samuelson MD
Minneapolis, Minnesota, USA
S. Yamane, M. Inoue, A. Arakawa, K. Kadonosono, Sutureless 27-gauge needle-guided intrascleral intraocular lens implantation with lamellar scleral dissection, Ophthalmology, 121, 2014, 61-66
1. Yamane S, Inoue M, Arakawa A, Kadonosono K. Sutureless 27-gauge needle-guided intrascleral intraocular lens implantation with lamellar scleral dissection. Ophthalmology
Other Cited Material
A. Ahmed IK. Scleral suture loop intraocular lens repositioning with GoreTex suture. Available on You Tube at: https://www.youtube.com/watch?v=4CykHf0Dk9Q
. Accessed April 14, 2016.