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Posteriorly dislocated anterior chamber intraocular lens
Posteriorly dislocated anterior chamber intraocular lens Randolph L. Johnston, M.D. Philadelphia, Pennsylvania Randall J. Olson, M.D. Mano Swartz, M.D. L. Keith Gates, M.D. Salt Lake City, Utah ABSTRACT A case of a posteriorly dislocated anterior chamber intraocular lens (IOL) is reported. Fig. 6.
(Menezo) Postoperative appearance of the eye.
The patient was discharged with an uncorrected visual acuity of 20/30. The unusual feature of this case is that a foreign body of volcanic nature (lava) had been well tolerated inside the vitreous chamber for over two years and had not been detected by B-scan ultrasonography. Because of an anterior vitrectomy, it had been displaced toward the anterior chamber, wedging itself between the iris and the lens.
Key Words: anterior chamber intraocular lens, Choyce Mark VIII style lens, posterior dislocation
Complications of anterior chamber intraocular lenses include Ellingson's syndrome (uveitis-glaucoma-hyphema)l and corneal \ edema related to endothelial cell loss. Dislocation of anterior chamber intraocular lenses is much less frequent than dislocation of iris fixated lenses. 2 We present an unusual case of a posteriorly dislocated anterior chamber intraocular lens in the presence of an intact iris. CASE REPORT A 79-year-old female had a cataract extraction of the left eye under general anesthesia in October 1981. No details of the surgery are known, but the patient related that she experienced nausea: and vomiting for one week postoperatively and never regained good vision after surgery. She was told soon after surgery that the intraocular lens (IOL) had "slipped." In October 1982, she was referred to the University of Utah Medical Center. Best corrected visual acuity at this time was 20/20 in the right eye and 20/300 in the left eye with an aphakic correction. Applanation tonometry revealed an intraocular pressure of 16 mm Hg in the right eye and 20 mm Hg in the left eye. Slitlamp examination in the right eye disclosed mild nuclear sclerosis; in the left eye, superior stromal edema and 2+ endothelial pigment were seen. The anterior From the Scheie Eye Institute, Philadelphia, Pennsylvania, and the Department of Ophthalmology, University of Utah Medical Center, Salt Lake City, Utah. Reprint requests to Randall J. Olson, M.D., Department of Ophthalmology, University of Utah Medical Center, 50 North Medical Drive, Salt Lake City, Utah 84132.
AM INTRA-OCULAR IMPLANT SOC J-VOL. 9, FALL 1983
473
chamber of the left eye was clear. An IOL was absent. She had a peripheral iridectomy superotemporally, a visible ciliary body cyst, and a small transillumination defect of the iris inferonasally. She appeared to have had an anterior vitrectomy, and capsular remnants were noted. Macular drusen were observed on fundus examination of the right eye. In the left eye, a pale optic nerve head, nerve fiber layer drop-out, and macular drusen were seen. A Choyce Mark VIII style solid polymethylmethacrylate (PMMA) lens was located inferiorly and anterior to the equator of the eye. The lens moved slightly, but did not touch the retina and was therefore apparently resting on a thin layer of cortical vitreous (Figure 1). There were no retinal hemorrhages
nor angle defects were present except the superotemporal peripheral iridectomy, which appeared much too small for a Choyce VIII style lens to pass through. Instead, we postulate that "double-looping," or iris capture by the inferior footplates, must have occurred during lens insertion. Subsequently, the effects of gravity, perhaps assisted by movement associated with vomiting, caused the inferior footplates to slip posterior to the iris and complete dislocation followed. The capsular remnants and evidence of anterior vitrectomy suggest that an extracapsular extraction with posterior chamber IOL insertion was intended but was aborted, possibly because of posterior capsule rupture. The lack of vitreous support of the iris diaphragm makes anterior chamber haptic placement more difficult. Precise placement of the inferior footplates appears critical to avoid this complication. At this time, no surgical treatment appears necessary. Criteria for IOL removal would be retinal injury (contusions or tears), persistent uveitis, or decreased vision from the lens shifting to block the visual axis. 7 In summary, we present an unusual case of a posteriorly dislocated anterior chamber IOL without an iris defect. REFERENCES
1. Ellingson FT: The uveitis-glaucoma-hyphema syndrome asso-
2. 3. 4. Fig.!.
(Johnston) Dislocated Choyce Mark VIII lens resting on peripheral retina.
or tears. Gonioscopy in the left eye failed to disclose an iris defect, except for the peripheral iridectomy. Visual acuity was eventually improved to 20/100 in the left eye with an aphakic correction. A visual6eld examination of the left eye revealed a superior altitudinal defect involving fixation. A CT-scan showed generalized central nervous system atrophy. Laboratory evaluation, includingCBC, ESR, B12, and FTA-ABS, was normal.
5. 6. 7.
ciated with the Mark VIII anterior chamber lens implant. Am Intra-Ocular Implant Soc J 4(2):50-53, 1978 Azar RF: Complications of anterior chamber implants. Cant Intraocul Lens Med J 4(1):30-33, 1978 Lindstrom RL, Nelson JD, Neist RL: Anterior chamber lens subluxation through a basal peripheral iridectomy. Am IntraOcular Implant Soc J 9:53-56, 1983 Tennant JL, Smirmaul H: Prevention and treatment of a complication of the Anchor Lens. Am Intra-Ocular Implant Soc J 8:363-364, 1982 Hales RH: Dislocation of the Kelman II anterior chamber intraocular lens. Am Intra-Ocular Implant Soc J 8:376-377, 1982 Olson RJ, Sevel D, Stevenson D: A histopathologic study of the Choyce VIII intraocular lens. Am J Ophthalmol 92:781-787, 1981 Shepard DD : Indications for intraocular lens removal. Ophthalmic Surg 8(3):144-148, 1977
DISCUSSION Anterior chamber IOLs may dislocate through defects in the iris such as iris tears or iridodialyses from the trauma oflens insertion, accidental iridotomy from corneoscleral scissors, iris colobomas, or peripheral iridectomies. 3-5 An IOL that is too small may rotate and subluxate through the peripheral iridectomy; if too large, it may cause localized iris atrophy, leading to an iris defect and subluxation. 6 In this case, neither iris 474
AM INTRA-OCULAR IMPLANT SOC
J-
VOL. 9, FALL 1983
(Menezo) Postoperative appearance of the eye.
The patient was discharged with an uncorrected visual acuity of 20/30. The unusual feature of this case is that a foreign body of volcanic nature (lava) had been well tolerated inside the vitreous chamber for over two years and had not been detected by B-scan ultrasonography. Because of an anterior vitrectomy, it had been displaced toward the anterior chamber, wedging itself between the iris and the lens.
Key Words: anterior chamber intraocular lens, Choyce Mark VIII style lens, posterior dislocation
Complications of anterior chamber intraocular lenses include Ellingson's syndrome (uveitis-glaucoma-hyphema)l and corneal \ edema related to endothelial cell loss. Dislocation of anterior chamber intraocular lenses is much less frequent than dislocation of iris fixated lenses. 2 We present an unusual case of a posteriorly dislocated anterior chamber intraocular lens in the presence of an intact iris. CASE REPORT A 79-year-old female had a cataract extraction of the left eye under general anesthesia in October 1981. No details of the surgery are known, but the patient related that she experienced nausea: and vomiting for one week postoperatively and never regained good vision after surgery. She was told soon after surgery that the intraocular lens (IOL) had "slipped." In October 1982, she was referred to the University of Utah Medical Center. Best corrected visual acuity at this time was 20/20 in the right eye and 20/300 in the left eye with an aphakic correction. Applanation tonometry revealed an intraocular pressure of 16 mm Hg in the right eye and 20 mm Hg in the left eye. Slitlamp examination in the right eye disclosed mild nuclear sclerosis; in the left eye, superior stromal edema and 2+ endothelial pigment were seen. The anterior From the Scheie Eye Institute, Philadelphia, Pennsylvania, and the Department of Ophthalmology, University of Utah Medical Center, Salt Lake City, Utah. Reprint requests to Randall J. Olson, M.D., Department of Ophthalmology, University of Utah Medical Center, 50 North Medical Drive, Salt Lake City, Utah 84132.
AM INTRA-OCULAR IMPLANT SOC J-VOL. 9, FALL 1983
473
chamber of the left eye was clear. An IOL was absent. She had a peripheral iridectomy superotemporally, a visible ciliary body cyst, and a small transillumination defect of the iris inferonasally. She appeared to have had an anterior vitrectomy, and capsular remnants were noted. Macular drusen were observed on fundus examination of the right eye. In the left eye, a pale optic nerve head, nerve fiber layer drop-out, and macular drusen were seen. A Choyce Mark VIII style solid polymethylmethacrylate (PMMA) lens was located inferiorly and anterior to the equator of the eye. The lens moved slightly, but did not touch the retina and was therefore apparently resting on a thin layer of cortical vitreous (Figure 1). There were no retinal hemorrhages
nor angle defects were present except the superotemporal peripheral iridectomy, which appeared much too small for a Choyce VIII style lens to pass through. Instead, we postulate that "double-looping," or iris capture by the inferior footplates, must have occurred during lens insertion. Subsequently, the effects of gravity, perhaps assisted by movement associated with vomiting, caused the inferior footplates to slip posterior to the iris and complete dislocation followed. The capsular remnants and evidence of anterior vitrectomy suggest that an extracapsular extraction with posterior chamber IOL insertion was intended but was aborted, possibly because of posterior capsule rupture. The lack of vitreous support of the iris diaphragm makes anterior chamber haptic placement more difficult. Precise placement of the inferior footplates appears critical to avoid this complication. At this time, no surgical treatment appears necessary. Criteria for IOL removal would be retinal injury (contusions or tears), persistent uveitis, or decreased vision from the lens shifting to block the visual axis. 7 In summary, we present an unusual case of a posteriorly dislocated anterior chamber IOL without an iris defect. REFERENCES
1. Ellingson FT: The uveitis-glaucoma-hyphema syndrome asso-
2. 3. 4. Fig.!.
(Johnston) Dislocated Choyce Mark VIII lens resting on peripheral retina.
or tears. Gonioscopy in the left eye failed to disclose an iris defect, except for the peripheral iridectomy. Visual acuity was eventually improved to 20/100 in the left eye with an aphakic correction. A visual6eld examination of the left eye revealed a superior altitudinal defect involving fixation. A CT-scan showed generalized central nervous system atrophy. Laboratory evaluation, includingCBC, ESR, B12, and FTA-ABS, was normal.
5. 6. 7.
ciated with the Mark VIII anterior chamber lens implant. Am Intra-Ocular Implant Soc J 4(2):50-53, 1978 Azar RF: Complications of anterior chamber implants. Cant Intraocul Lens Med J 4(1):30-33, 1978 Lindstrom RL, Nelson JD, Neist RL: Anterior chamber lens subluxation through a basal peripheral iridectomy. Am IntraOcular Implant Soc J 9:53-56, 1983 Tennant JL, Smirmaul H: Prevention and treatment of a complication of the Anchor Lens. Am Intra-Ocular Implant Soc J 8:363-364, 1982 Hales RH: Dislocation of the Kelman II anterior chamber intraocular lens. Am Intra-Ocular Implant Soc J 8:376-377, 1982 Olson RJ, Sevel D, Stevenson D: A histopathologic study of the Choyce VIII intraocular lens. Am J Ophthalmol 92:781-787, 1981 Shepard DD : Indications for intraocular lens removal. Ophthalmic Surg 8(3):144-148, 1977
DISCUSSION Anterior chamber IOLs may dislocate through defects in the iris such as iris tears or iridodialyses from the trauma oflens insertion, accidental iridotomy from corneoscleral scissors, iris colobomas, or peripheral iridectomies. 3-5 An IOL that is too small may rotate and subluxate through the peripheral iridectomy; if too large, it may cause localized iris atrophy, leading to an iris defect and subluxation. 6 In this case, neither iris 474
AM INTRA-OCULAR IMPLANT SOC
J-
VOL. 9, FALL 1983