Secondary anterior capsulotomy in pseudophakic eyes

Abstract

 

This report describes a 1-handed technique and a 2-handed technique anterior capsulotomy in pseudophakic eyes. Each technique was used in a case of proliferative vitreoretinopathy accompanying anterior capsule contraction that occurred following cataract and intraocular lens (IOL) implantation. A capsulorhexis forceps and a stab knife were inserted into the anterior chamber, and the capsule contraction alleviated without extracting the IOL in both cases. Secondary anterior capsulotomy contributed to both the surgeon's visibility during intraocular surgery, including the subsequent vitreous surgery, and the patient's postoperative visual acuity. The transparency of the pupil region was restored. While the 1-handed technique involves the risk of adversely affecting Zinn's zonule, the 2-handed technique does not place a burden on Zinn's zonule and is thought to considerably improve the surgeon's visibility in subsequent vitreoretinal surgery.

This report describes 2 techniques of invasive anterior capsulotomy prior to vitreoretinal surgery to improve both the patient's visual acuity and the surgeon's visibility. This may be carried out by means of a 1-handed technique using a capsulorhexis forceps inserted via a single site on the corneal limbus alone or by using an incision knife and a capsulorhexis forceps via 2 sites on the corneal limbus (2-handed technique). The techniques were used in 2 pseudophakic eyes of 2 patients with proliferative vitreoretinopathy requiring anterior capsulotomy prior to vitreoretinal surgery and showing strong capsule opacity and capsule contraction.

Surgical Technique

One-Handed

An incision wound is made at the 3 o'clock position on the corneal limbus using an incision knife (20 gauge, a V-lance). After the anterior capsule is filled with a viscoelastic substance, a capsule incision is made with a capsulorhexis forceps (23G, Model AE-4388, ASICO). The capsule is grasped with the forceps in the opaque region (Figure 1).

Figure 1.: Secondary capsulotomy by the 1-handed technique. The forceps, having a cystotome function, facilitate capsulotomy.

The capsulorhexis forceps can be used as a forceps or cystotome when necessary. Figure 2 shows a distal part of the forceps, a top view of the forceps when opened and side view of the forceps when closed.

Figure 2.: Two views of the forceps. Top: Top view of the forceps when opened. Bottom: Side view of the forceps when closed.

Two-Handed

Incisions are prepared at 2 positions on the corneal limbus at 3 o'clock and 10 o'clock using an incision knife (20 gauge, a V-lance). After the anterior chamber is filled with a viscoelastic substance, the capsule is incised in the opaque region with a capsulorhexis forceps (23G, Model AE-4388, ASICO) held in 1 hand; the incision knife is held in the other hand (Figure 3).

Figure 3.: Secondary capsulotomy by the 2-handed technique. The incision knife is on the right and the forceps, having a cystotome function, on the left.

Case Reports

Case 1

An 80-year-old woman received cataract and intraocular lens (IOL) implantation surgery in her left eye in November 2000. The patient was referred by her physician on April 4, 2001, due to decreased visual acuity accompanying proliferative vitreoretinopathy. Visual acuity was 1.0 (20/20, uncorrected) in the right eye and hand motion (HM) in the left eye. As macular detachment accompanying proliferative vitreoretinopathy was observed on the fundus in the left eye, the patient was admitted for emergency surgery. The surgery involved anterior capsulotomy by the 1-handed technique for capsule contraction and fibrous opacity, followed by 3-port pars plana vitrectomy, intraocular photocoagulation, and gas exchange with infusion of 1.5 mL sulfur hexafluoride (SF₆) gas. The surgery was completed without removal of the IOL in her left eye.

Case 2

The left eye of a 64-year-old man was diagnosed with retinal detachment and had surgery at a university hospital on February 27, 2002. The surgical method was combined pars plana vitrectomy and phacoemulsification and aspiration with in-the-bag fixation of an IOL. However, as retinal detachment recurred, the patient had pars plana vitrectomy and silicone oil tamponade in the left eye on March 6. As he failed to show postoperative improvement in visual acuity, he was admitted to the hospital on July 3. The patient's visual acuity was 1.00 (20/20, uncorrected) in the right eye and 0.06 (6/100) in the left eye. The left eye showed iritis, and as visual acuity on correction decreased to 0.20 (4/20), the patient was switched from fluoromethalone 0.1% ophthalmic solution (Flumetholon) to betamethasone ophthalmic solution (Rinderon), and a strong antiinflammatory effect was obtained. Moreover, silicone oil was present in the fundus in the left eye and proliferative changes were observed in the temporal retina. The patient was observed over time. As no recurrence of the retinitis was seen, he was scheduled for surgery on March 5, 2003, to improve visual acuity, remove the proliferative membrane, and extract the silicone oil. The surgery involved anterior capsulotomy by the 2-handed technique for anterior capsule contraction and fibrous strong opacity. The patient had 3-port pars plana vitrectomy, removal of the silicone oil, intraocular photocoagulation, and gas exchange, completed by injection of triamcinolone 0.8 mg and 1.5 mL SF₆ gas. The surgery was performed without removal of the IOL.

Results

Case 1

Following anterior capsulotomy by the 1-handed technique, the surgeon's intraoperative visibility was improved and the proliferative membrane was safely removed. Postoperative slitlamp examinations for a period of 3 years showed no recurrence of anterior capsule contraction, and corrected visual acuity, which had been assessed as HM prior to surgery, improved to 0.50 (10/20) and was maintained at this level.

Case 2

Following anterior capsulotomy by the 2-handed technique, the surgeon's intraocular visibility improved, and the proliferative membrane was safely removed. At slitlamp observation 10 months after surgery, no recurrence of anterior capsule contraction was observed, nor was any iritis seen. Changes in Zinn's zonule seemed minor, and no dislocation or concussion of the IOL was observed. Visual acuity in the left eye improved by 2 stages to 0.30 (6/20), and the retina also showed favorable extension with no redetachment observed.

Discussion

In general, in the case of proliferative vitreoretinopathy, if the surgeon's intraocular visibility is assessed as poor, vitreoretinal surgery is performed after removal of the IOL. If proliferative changes in the peripheral retina are not conclusively treated, proliferation will recur, resulting in recurrence of proliferative vitreoretinopathy. The selection of secondary anterior capsulotomy was thought to be significant as this technique improves both the surgeon's visibility during vitreoretinal surgery and the patient's postoperative visual acuity.

There have been numerous reports on incision/relaxation of the anterior capsule, generally by means of neodymium:YAG laser irradiation, to expand the transparent region in the pupil area.^1–5 In contrast, the reason there have been few reports on invasive surgery is that such surgery is considered to entail a possible risk for dislocation of the IOL in the bag. Reports of invasive surgery have included a case in which an incision measuring approximately 3 mm was made in the corneal limbus and the opaque area was removed using an anterior capsule punch or forceps⁶ as well as excision by diathermy.⁷ Excision/removal of the contracted torn capsule edge is performed using a capsulotomy punch and forceps via an incision in the corneal limbus measuring approximately 3 mm, but the drawbacks of this procedure include that it is complex, it is difficult to maintain the anterior chamber depth, and the site of anterior capsule contraction cannot be largely removed. However, it is thought that all of these drawbacks can be overcome using the 2-handed technique of anterior capsulotomy. A characteristic of the 2-handed anterior capsulotomy technique is that it enables intraocular procedures to be carried out via the incision wounds made by a knife (20G) in the corneal limbus. These small incisions obviate the need for postoperative suturing and cause little postoperative astigmatism. Moreover, they obviate the need for the IOL removals conducted in the past. While the 1-handed technique might involve the risk for adversely affecting Zinn's zonule, it was thought that the 2-handed technique would be preferable to minimize the tension placed on Zinn's zonule and the pars plana. The technique of incising the capsule was used, which showed contraction of the pupil area and opacity; the capsulorhexis forceps was held in 1 hand and an MVR knife or V-lance in the other. The 2-handed technique is useful to tear a thick and opaque capsule for the surgeon, and it makes a major contribution toward restoring the patient's visual acuity.