- Email: [email protected]
Complications Associated with Posterior Chamber Lenses
Symposium: Intraocular Lenses f
f
f
COMPLICATIONS ASSOCIATED WITH POSTERIOR CHAMBER LENSES RICHARD P. KRATZ, MD VAN NUYS, CALIFORNIA Different types of posterior chamber lenses and their complications are discussed and compared with complications of anterior chamber lenses, pupilsupported lenses, and capsular-fixated lenses. Special emphasis is placed on the Shearing intraocular lens.
POSTERIOR chamber intraocular lenses were introduced by Harold Ridley, MD, in 1949. They fell into disfavor mainly because of a 6% subluxation rate into the posterior chamber, iritis, secondary glaucoma, and eventual extraction of the implant in 15% of cases. Interest in posterior chamber intraocular lenses was renewed when John Pearce, MD, introduced a tripod posterior chamber lens. William Simcoe, MD, made several bipod posterior chamber lenses that were sutured both inferiorly and superiorly to the iris. James Little, MD, Eric Arnott, MD, and William Harris, MD, made a quadrapod posterior chamber lens. All these lenses were difficult to insert through the pupil because they were rigid. They also had occasional decentration problems because of the 4-mm optic size. This
Submitted for publication Oct 24 , 1978. From the University of Southern California, Los Angeles. Presented in combination with the Contact Lens Association of Ophthalmologists at the 1978 Anqual Meeting of the American Academy of Ophthalmology, Kansas City, Mo, Oct 22-26.
resulted in monocular diplopia caused by the pseudophakic-aphakic vision. The same problem occurred if the pupil dilated larger than 4 mm. The Harris lens was later modified to 5 mm and the Simcoe lens from 5 to 6 mm. All these lenses required extracapsular cataract extraction, which caused problems of handling the opacification of the posterior capsule. The modern posterior chamber lens has specific advantages over the pupillary-supported lenses: (1) single-plane lens, (2) no hooks or sutures in the iris, (3) wide dilation of pupil, (4) use of miotics with no danger of sphincter erosion, (5) rare pupillary synechiae, (6) no pupil laceration, (7) rare displaced pupils, and (8) rare subluxation. There were also advantages over Choyce anterior chamber lenses, which included a single size for every lens power, no trabecular touch, no Choyce-type tenderness on touch, no pain on scleral depression, and no iris tucking. The lens developed by Shearing overcame some of the disadvantages of the other posterior chamber lenses. It could be easily inserted without lifting the cornea. Flexible loops allowed passage through even a small pupil, with minimal intraocular manipulation. There was excellent centration, and the optic
659
660
RICHARD P. KRATZ
size was large enough to allow for slight variations in pupil centration or nighttime mydriasis. No major complications resulted. However, there have been few case studies done with this lens. The first implant was performed in March 1977 by Shearing, and the follow-up period has been short. This lens is not intended for intracapsular surgery. It ~auses pressure against the ciliary body, and late capsulotomy may be required. The author found that the average depth from the endothelium to the pseudophakos optic was 3.4 mm in the normal lens and 4.0 mm in the modified lens, with a 100 anterior angulation of the loops. The angulation permitted easier positioning of the loops into the ciliary sulcus and avoided pupil capturing, in which a portion of the pupil passes behind the optic.
OPHTH AAO
his visual acuity was 20 / 50 despite senile macular degeneration. The visual acuity was 20/40 or better in 92% of the patients. The Terry quantitative keratometer used through the latter part of the series provided a controlled method of regulating astigmatism, and it was common to find visual acuities of 20/ 20, 20/ 30, or 20/ 40 during the first postoperative visit. Visual acuities of 20/ 50 or less were caused by senile macular degeneration, cystoid macular edema, glaucomatous atrophy, amblyopia, vitritis, and foveal cyst.
The complications during followup included 20 cases of senile macular degeneration and seven cases of clinical cystoid macular edema but only one retinal detachment. There were no cases of corneal dystrophy, which is unlikely to occur since the implant is in the posterior chamber. One subluxation was a secondAt present approximately 3,500 ary implant and the other an Shearing lenses have been im- intraocular lens exchanged for a planted. Our office has performed nonfixed metal loop iridocapsular 536 implant procedures, mostly by lens. In both cases the posterior Kelman phacoemulsification in the capsule was disinserted inferiorly. posterior chamber. Eight were lens The lenses were rotated 900 and exchanges for subluxated iridocap- have since fixed satisfactorily. There sular lenses, one combined with a were five cases of pupil capture, corneal transplant. Five were sec- in which approximately one third ondary implants. Of the 536 cases, of the iris dropped posterior to the 469 were followed up for 2 to 11 edge of the lens. These occurred months. The patients averaged 71.5 beca use the Shearing lenses are years of age. The youngest implant 13 mm long, and some tend to bow patient was 49 years old, and the slightly forward in the eye. In each implant was performed because his case the lens was easily repositioned left ann and shoulder were paralyzed by slightly depressing with a Haab from poliomyelitis. Visual acuity knife. The modification of 100 antetwo months postoperatively was rior angulation of the loops should 20/ 20. The oldest implant patient prevent further occurrence of this was 92 years of age. Although the problem. patient was physically infirm, he was mentally alert. His visual acuEarly in the series two severe and ity before surgery was hand mo- three moderate cases of iritis were tions. Two months postoperatively present on the first postoperative
VOLU ME 86 APRI L 1979
SYMPOSIUM ON INTRAOCULAR LENSES
day. Jaffe stated that in similar problems with Binkhorst iridocapsular lenses, he found that this complication could be avoided by soaking the intraocular lens in saline for 30 minutes before insertion. After this advice was followed, our epidemic of severe and moderate iritis ceased. There were seven cases of mild iritis and three mild cases of vitritis. Severe vitritis developed in one patient seven weeks after surgery. At six weeks the visual acuity was 20/ 25. Corticosteroid therapy was started, but the patient soon had pars planitis with "snowballs" visible on indirect ophthalmoscopy of the pars plana. Hypopyon ensued and the lens was removed. The cause of the pars planitis was not established. During the same period the author saw pars planitis after phacoemulsification and after intracapsular cataract extraction, both without implanted intraocular lenses. Glaucoma does not appear to be a contraindication with a posterior chamber lens, as it is when the lens is placed prepupillary. To complete the phacoemulsification, it was some-
661
times necessary to perform a sector iridotomy and then suture both the sphincter and the midstroma with Prolene to restore the pupil to its round state. In four cases the procedure was combined with trabeculectomy. Transient elevation of tension, presumably caused by corticosteroids, occurred five times. Some complications related to wound closure were controlled by the Terry quantitative keratometer. These wounds were closed loosely to minimize astigmatism, but sometimes they were too loose, resulting in resuturing two times and vitreous prolapse three times (one patient fell down a flight of stairs, causing vitreous prolapse without subluxating the Shearing lens). There was one pupil block, which was treated with laser iridotomy. Residual cortex was aspirated from the anterior chamber once. It has been concluded that the Shearing lens may be safely and effectively combin~ed with extracapsular cataract extraction or phacoemulsification with a mImmum of complications.
f
f
COMPLICATIONS ASSOCIATED WITH POSTERIOR CHAMBER LENSES RICHARD P. KRATZ, MD VAN NUYS, CALIFORNIA Different types of posterior chamber lenses and their complications are discussed and compared with complications of anterior chamber lenses, pupilsupported lenses, and capsular-fixated lenses. Special emphasis is placed on the Shearing intraocular lens.
POSTERIOR chamber intraocular lenses were introduced by Harold Ridley, MD, in 1949. They fell into disfavor mainly because of a 6% subluxation rate into the posterior chamber, iritis, secondary glaucoma, and eventual extraction of the implant in 15% of cases. Interest in posterior chamber intraocular lenses was renewed when John Pearce, MD, introduced a tripod posterior chamber lens. William Simcoe, MD, made several bipod posterior chamber lenses that were sutured both inferiorly and superiorly to the iris. James Little, MD, Eric Arnott, MD, and William Harris, MD, made a quadrapod posterior chamber lens. All these lenses were difficult to insert through the pupil because they were rigid. They also had occasional decentration problems because of the 4-mm optic size. This
Submitted for publication Oct 24 , 1978. From the University of Southern California, Los Angeles. Presented in combination with the Contact Lens Association of Ophthalmologists at the 1978 Anqual Meeting of the American Academy of Ophthalmology, Kansas City, Mo, Oct 22-26.
resulted in monocular diplopia caused by the pseudophakic-aphakic vision. The same problem occurred if the pupil dilated larger than 4 mm. The Harris lens was later modified to 5 mm and the Simcoe lens from 5 to 6 mm. All these lenses required extracapsular cataract extraction, which caused problems of handling the opacification of the posterior capsule. The modern posterior chamber lens has specific advantages over the pupillary-supported lenses: (1) single-plane lens, (2) no hooks or sutures in the iris, (3) wide dilation of pupil, (4) use of miotics with no danger of sphincter erosion, (5) rare pupillary synechiae, (6) no pupil laceration, (7) rare displaced pupils, and (8) rare subluxation. There were also advantages over Choyce anterior chamber lenses, which included a single size for every lens power, no trabecular touch, no Choyce-type tenderness on touch, no pain on scleral depression, and no iris tucking. The lens developed by Shearing overcame some of the disadvantages of the other posterior chamber lenses. It could be easily inserted without lifting the cornea. Flexible loops allowed passage through even a small pupil, with minimal intraocular manipulation. There was excellent centration, and the optic
659
660
RICHARD P. KRATZ
size was large enough to allow for slight variations in pupil centration or nighttime mydriasis. No major complications resulted. However, there have been few case studies done with this lens. The first implant was performed in March 1977 by Shearing, and the follow-up period has been short. This lens is not intended for intracapsular surgery. It ~auses pressure against the ciliary body, and late capsulotomy may be required. The author found that the average depth from the endothelium to the pseudophakos optic was 3.4 mm in the normal lens and 4.0 mm in the modified lens, with a 100 anterior angulation of the loops. The angulation permitted easier positioning of the loops into the ciliary sulcus and avoided pupil capturing, in which a portion of the pupil passes behind the optic.
OPHTH AAO
his visual acuity was 20 / 50 despite senile macular degeneration. The visual acuity was 20/40 or better in 92% of the patients. The Terry quantitative keratometer used through the latter part of the series provided a controlled method of regulating astigmatism, and it was common to find visual acuities of 20/ 20, 20/ 30, or 20/ 40 during the first postoperative visit. Visual acuities of 20/ 50 or less were caused by senile macular degeneration, cystoid macular edema, glaucomatous atrophy, amblyopia, vitritis, and foveal cyst.
The complications during followup included 20 cases of senile macular degeneration and seven cases of clinical cystoid macular edema but only one retinal detachment. There were no cases of corneal dystrophy, which is unlikely to occur since the implant is in the posterior chamber. One subluxation was a secondAt present approximately 3,500 ary implant and the other an Shearing lenses have been im- intraocular lens exchanged for a planted. Our office has performed nonfixed metal loop iridocapsular 536 implant procedures, mostly by lens. In both cases the posterior Kelman phacoemulsification in the capsule was disinserted inferiorly. posterior chamber. Eight were lens The lenses were rotated 900 and exchanges for subluxated iridocap- have since fixed satisfactorily. There sular lenses, one combined with a were five cases of pupil capture, corneal transplant. Five were sec- in which approximately one third ondary implants. Of the 536 cases, of the iris dropped posterior to the 469 were followed up for 2 to 11 edge of the lens. These occurred months. The patients averaged 71.5 beca use the Shearing lenses are years of age. The youngest implant 13 mm long, and some tend to bow patient was 49 years old, and the slightly forward in the eye. In each implant was performed because his case the lens was easily repositioned left ann and shoulder were paralyzed by slightly depressing with a Haab from poliomyelitis. Visual acuity knife. The modification of 100 antetwo months postoperatively was rior angulation of the loops should 20/ 20. The oldest implant patient prevent further occurrence of this was 92 years of age. Although the problem. patient was physically infirm, he was mentally alert. His visual acuEarly in the series two severe and ity before surgery was hand mo- three moderate cases of iritis were tions. Two months postoperatively present on the first postoperative
VOLU ME 86 APRI L 1979
SYMPOSIUM ON INTRAOCULAR LENSES
day. Jaffe stated that in similar problems with Binkhorst iridocapsular lenses, he found that this complication could be avoided by soaking the intraocular lens in saline for 30 minutes before insertion. After this advice was followed, our epidemic of severe and moderate iritis ceased. There were seven cases of mild iritis and three mild cases of vitritis. Severe vitritis developed in one patient seven weeks after surgery. At six weeks the visual acuity was 20/ 25. Corticosteroid therapy was started, but the patient soon had pars planitis with "snowballs" visible on indirect ophthalmoscopy of the pars plana. Hypopyon ensued and the lens was removed. The cause of the pars planitis was not established. During the same period the author saw pars planitis after phacoemulsification and after intracapsular cataract extraction, both without implanted intraocular lenses. Glaucoma does not appear to be a contraindication with a posterior chamber lens, as it is when the lens is placed prepupillary. To complete the phacoemulsification, it was some-
661
times necessary to perform a sector iridotomy and then suture both the sphincter and the midstroma with Prolene to restore the pupil to its round state. In four cases the procedure was combined with trabeculectomy. Transient elevation of tension, presumably caused by corticosteroids, occurred five times. Some complications related to wound closure were controlled by the Terry quantitative keratometer. These wounds were closed loosely to minimize astigmatism, but sometimes they were too loose, resulting in resuturing two times and vitreous prolapse three times (one patient fell down a flight of stairs, causing vitreous prolapse without subluxating the Shearing lens). There was one pupil block, which was treated with laser iridotomy. Residual cortex was aspirated from the anterior chamber once. It has been concluded that the Shearing lens may be safely and effectively combin~ed with extracapsular cataract extraction or phacoemulsification with a mImmum of complications.