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PURPOSE: To examine postmortem human globes containing an anterior chamber and a posterior chamber intraocular lens (IOL).

SETTING: Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Charleston, South Carolina, USA.

METHODS: The globes were sectioned at the equator, and the anterior and posterior segments were macroscopically examined. Gross photographs were taken using the Miyake-Apple posterior photographic technique. Histological sections were cut and stained with hematoxylin and eosin, periodic acid-Schiff, and Masson's trichrome.

RESULTS: Histopathological findings included a large Soemmering's ring, a tear in the posterior capsule, 1 haptic of the anterior chamber IOL displaced into the iridectomy, thin and atrophic corneal epithelium, separation of Bowman's layer and stroma by fibrovascular tissue, and atrophy of the retinal ganglion cell layer and nerve fiber layer.

CONCLUSION: In cases in which secondary IOL implantation is indicated, removing the dislocated IOL appears to be a reasonable choice.

The implantable miniaturized telescope (IMT) is the first intraocular magnifying system proposed for optical correction in patients with age-related macular degeneration (ARMD). The optical component is embedded in a carrying device designed as an intraocular lens that is implanted after cataract surgery. In this study, we report findings on an IMT that was explanted because of aqueous infiltration into its optic and describe the configuration of this device and the surgical technique required for its implantation. The patient, a 75-year-old male with bilateral cataract and nonexudative ARMD, underwent phacoemulsification with implantation of an IMT in the right eye. The rigid device, weighing 46.1 mg in aqueous, has an overall diameter of 13.5 mm and requires implantation through a large limbal incision. It is fixated at the 6 to 12 o'clock meridian. Follow-up examination revealed the presence of numerous droplets inside the IMT optic. The device was explanted and sent to our center for evaluation. A large fissure was found on the carrying device. However, it was unlikely the site for aqueous infiltration. Microdefects at the level of the sealing of the optical cylinder appeared to provide the opening for the inflow of aqueous that formed droplets. Based on the findings of this report the manufacturer has modified the sealing technique to avoid this complication. Current clinical trials are now ongoing to assess the efficacy of this device in providing visual rehabilitation for ARMD patients.

PURPOSE: To compare the shape recovery ratios after compression of haptic materials used in the manufacture of intraocular lenses (IOLs).

SETTING: Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS: The loop memory of 40 silicone-optic posterior chamber IOLs was studied. All the IOLs had modified-C haptics made of poly(methyl methacrylate) (PMMA; n = 10), polyimide (n = 10), polyvinylidene fluoride (PVDF; n = 10), and polypropylene (PP; n = 10). After the overall diameter of each lens was measured (day 0), the lenses were inserted into plastic wells (9.5 mm in diameter) and immersed in water (37 degrees C) for 1 month. They were then placed on an open plate and allowed to reexpand for 2 months. Overall diameter measurements were performed within 5 minutes of the IOLs' removal from the wells and at subsequent time points (days 14, 28, 30, 60, 74, 88, and 95).

RESULTS: The loop memory of each lens was expressed as the difference between the initial overall diameter measurement (pretest) and the measurement at each time point; the lower the value, the higher the memory. The overall difference among the 4 groups was statistically significant at each time point (P < or = .001). From days 30 to 95, silicone-PMMA, silicone-elastimide, and silicone-PVDF IOLs had similar loop memory mean values, which were significantly lower than the mean value of silicone-PP IOLs (P <.05). The latter design tended to be deformed after removal from the wells, with increased optic-haptic angulation.

CONCLUSION: Studying the loop memory of haptic materials (PMMA, polyimide, PVDF, and PP) used in the manufacture of posterior chamber IOLs can help surgeons choose an appropriate IOL for each patient.

PURPOSE: To evaluate the efficacy of an intracapsular ring releasing 5-fluorouracil (5-FU) in preventing posterior capsule opacification (PCO) in rabbit eyes.

SETTING: Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA, and Chu Morvan, Department d'Ophtalmologie, University of Brest, France.

METHODS: Seventeen rabbits were divided into 3 groups: Group 1, 6 rabbits (6 eyes), had phacoemulsification only (control group); Group 2, 6 rabbits (6 eyes), had phacoemulsification with implantation of an open-loop hydrogel intracapsular ring; Group 3, 5 rabbits (5 eyes), had phacoemulsification with implantation of a ring with sustained release of 0.25 microg/h of 5-FU for 9 days. All eyes were followed for 8 weeks before enucleation. Capsular bag shrinkage and the position of the intracapsular ring were assessed, and central and peripheral PCO was evaluated for intensity and area by stereomicroscopy from a posterior (Miyake-Apple) view. The residual equatorial lens epithelial cells (LECs) were counted by the same observer in histological sections. Transmission electron microscopy (TEM) of the cornea, capsular bag, and retina was done to evaluate the toxicity of 5-FU.

RESULTS: No significant difference was seen in the degree of capsular bag shrinkage in the 3 groups. The intracapsular ring was decentered in 2 eyes (1 each in Groups 2 and 3). There was a statistically significant difference (P <.05, Student t test) between Group 1 and Groups 2 and 3 in the area and intensity of central PCO. There was no difference between Groups 2 and 3 in the intensity of central PCO. No evidence of 5-FU toxicity to intraocular structures (cornea, capsular bag, and retina) was demonstrated on TEM analysis.

CONCLUSION: Implantation of an intracapsular ring may prevent central PCO after cataract surgery by mechanically blocking LEC migration toward the central visual axis. The potential pharmacological effect of 5-FU in PCO prevention was not demonstrated.

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