Intraocular lens removal for chronic cystoid macular edema

Surgical management of uveitis-glaucoma-hyphema syndrome

AIM

To report outcomes of patients after intraocular lens (IOL) repositioning or exchange for the version of the uveitis-glaucoma-hyphema (UGH) syndrome that does not include closed loop anterior chamber IOL (nUGH).

METHODS

Chart review of patients with nUGH who underwent IOL repositioning or exchange by one surgeon were reviewed. The main outcome measures were best corrected visual acuity (BCVA) as a decimal fraction preoperatively and postoperatively after IOL repositioning or exchange. Clinical findings evaluated included the presence of uveitis, hyphema, elevated intraocular pressure (IOP), and other complications such as pigment dispersion or vitreous hemorrhage. The number of anti-inflammatory and glaucoma medications were assessed before and after IOL repositioning or exchange.

RESULTS

The study included 14 pseudophakic eyes. The median time at the onset of contemporary UGH after cataract extraction and IOL implantation (CE/IOL) was 7.5y. IOL repositioning or exchange was performed at a mean duration of 8.1±4.7mo (median: 4mo) after onset of UGH. The mean BCVA was improved from 0.45±0.26 preoperatively after onset of UGH syndrome to 0.76±0.22 (P=0.016) after IOL repositioning or exchange. Among the 14 eyes, uveitis, elevated IOP, and hyphema were present preoperatively in 13, 13, and 6 eyes, respectively. Uveitis and hyphema resolved in all cases after IOL surgery. The mean IOP was reduced from 26.4±4.5 mm Hg preoperatively to 14.7±4.9 postoperatively (P=0.01). The mean number of glaucoma medications used was reduced from 1.7±1.1 medications preoperatively to 0.8±1.08 (P=0.04) postoperatively.

CONCLUSION

IOL repositioning or exchange is an effective treatment in many cases for medically resistant contemporary UGH syndrome.

[History of the development of intraocular lenses]

Even though cataract surgery has been practiced for over 2000 years, modern cataract surgery started just some 50 years ago. with the first IOL implantation by Sir Harold Ridley. The development of intraocular lenses was accompanied by great successes and disasters. With the fast development of cataract surgical techniques over the past 15 years (ECCE, Phacoemulsification, Capsulorhexis) a successful marriage between IOL-developments and surgery was established. Indication profiles for cataract surgery and IOL implantation extended to more and more patient groups. At this time classical cataract surgery is further developing into refractive intraocular lens surgery to correct higher ametropia in clear lens or phakic eyes. This development was only possible because of the improvements of surgical techniques and implants in classical cataract surgery.

Long-term follow-up of primary anterior chamber intraocular lens implantation

PURPOSE

To evaluate the long-term outcome in eyes having primary anterior chamber intraocular lens (AC IOL) implantation.

SETTING

Kimura Eye and Internal Medicine Hospital, Hiroshima, Japan.

METHODS

Primary AC IOL implantation was performed in 171 eyes from 1983 to 1988. Two lenses were implanted: the open C-loop Simcoe lens and the 4-point fixation Kelman lens. In 86 eyes that had a mean follow-up of 9 years 7 months, visual acuity, corneal endothelial cell density, pupil shape, and the presence of associated complications were examined.

RESULTS

Although the final visual acuity was 0.5 or better in 60 eyes (69%), corneal endothelial cell density was less than 2000 cells/mm2 in 46 eyes (57%). Postoperative complications included a deformed pupil in 48 eyes (56%) and bullous keratopathy in 12 eyes (14%). In 14 eyes the AC IOL was explanted; 11 of these were the open C-loop Simcoe lens.

CONCLUSION

Although our findings show that the open C-loop AC IOL (Simcoe) is contraindicated, implantation of the 4-point fixation AC IOL may be acceptable in selected cases.

Intraocular lens complications requiring removal or exchange

Intraocular lens (IOL)-related complications are caused primarily by mechanical trauma, inflammatory or infectious complications, or optical problems. Complications may occur at the time of surgery or be the result of an ongoing postoperative process. Mechanical and inflammatory injury may produce corneal decompensation, cystoid macular edema, hyphema, uveitis, and glaucoma, causing reduced vision and in some cases chronic pain. Optical problems may be due to a wrong power of the IOL or to postoperative decentration or dislocation of the lens. Ophthalmologists should be aware of the indications for IOL removal or exchange in those patients who have ongoing IOL-induced injury or impairment. Removal or exchange of an IOL frequently involves a complex decision-making process and is often associated with immense technical challenge. Various medical and surgical treatments may be tried to correct IOL problems before the decision is made to remove or exchange the lens.

Are there acceptable anterior chamber intraocular lenses for clinical use in the 1990s? An analysis of 4104 explanted anterior chamber intraocular lenses

PURPOSE

The authors pose the question as to whether there are any anterior chamber intraocular lenses (AC IOLs) acceptable for clinical use in the 1990s.

METHODS

Data on the incidence and types of complications of 4104 AC IOLs that were submitted to the Center for IOL Research from 1982 to 1993 were retrieved from the laboratory database and analyzed using cumulative frequency calculations and the chi-square test. Normalized explantation rates were related to implantation rates that were derived from market-share analysis.

RESULTS

Of 4104 explanted IOLs, 50% were closed-loop designs (n = 2095/4104); 26% (1100/4104) were miscellaneous, older designs; and 22% (919/4104) were open-loop lenses. The most important complications were corneal pathology (2065/4104) and inflammation (1370/4104). Closed-loop designs were responsible for almost 80% of corneal pathology, with an increasing complication rate with ongoing implant duration (P < 0.0001). Open-loop AC IOLs showed, in relation to their normalized rate of implantation, a significantly lower rate of complications and explantations (P < 0.01).

CONCLUSION

Complication rates of flexible, open-loop AC IOLs are much lower than previously assumed. They should be distinguished clearly from most older AC IOL designs. Consideration of these lenses as an alternative to sutured posterior chamber IOLs for secondary or exchange implantation may be warranted for selected clinical indications. They also could provide an alternative to the aphakic spectacle rehabilitation program in developing countries, which will have a positive impact on the overwhelming backlog of patients with cataract in the underprivileged world.

Intraocular complications associated with the Dubroff anterior chamber lens

We examined a series of 53 consecutive eyes form which Dubroff-style anterior chamber lenses were explanted. The mean time from implantation to explantation was 46.21 months (range six to 99 months). Problems leading to explantation included bullous keratopathy (83%), glaucoma (51%), chronic cystoid macular edema (40%), and iritis (13%). Molteno valves were required in 9% of eyes. Progressive anterior synechias resulted in intraocular lens displacement against the cornea in 19%. The Dubroff lenses caused problems similar to those previously observed with closed-loop anterior chamber lenses but had a higher incidence of severe glaucoma and progressive peripheral anterior synechias.

Indications for and results of intraocular lens explantation

We reviewed the medical records of 97 patients who had 101 consecutive intraocular lens (IOL) explantation procedures, with or without exchange, at the University of Florida Eye Center from January 1, 1983, to December 31, 1987. The majority of the removed IOLs were anterior chamber styles (53.9%), followed by iris-fixated lenses (33.7%). The most common indications for surgery included pseudophakic bullous keratopathy (PBK)--69%, uveitis-glaucoma-hyphema (UGH) syndrome--9%, and IOL instability--7%. The best visual outcome was seen in patients with IOL instability; 50% achieved 20/40 or better visual acuity. Forty one percent of patients with PBK, who had IOL explantation/exchange combined with penetrating keratoplasty, achieved 20/40 or better visual acuity. The poorest visual outcome was seen in patients with the UGH syndrome; 83% had a final acuity of 20/200 or worse. However, these patients achieved resolution of their pain and inflammation and better control of their intraocular pressure as a result of the surgery. Complications leading to IOL explantation tended to occur months to years after the original surgery in patients with closed-loop, semi-flexible anterior chamber lenses and iris-fixated lenses. Posterior chamber lenses were most often removed because of complications unrelated to the implant.