Plastic exfoliations from the cartridge after implantation of a hydrophilic acrylic lens without viscoelastic material

Evaluation of Parameters and Nozzle Tip Damage after Clinical Use of Three Hydrophilic Intraocular Lens Injector Models

Purpose

To assess the nozzle tip damage and the parameters of three different hydrophilic intraocular lens (IOL) injector models.

Methods

After routine cataract surgeries at the University Eye Hospital Heidelberg, all the used IOL injectors were collected from the operating room and sent to our laboratory. Nozzle tip damage was assessed under a microscope and graded as follows: no damage (grade 0), slight scratches (1), deep scratches (2), extensions (3), cracks (4), and bursts (5). Each damage grade was assigned a score from 0 to 5, and the total damage score for each injector system was calculated and compared. Nozzle tip parameters (diameters and areas), plunger tip parameters, and tip angles were also measured in each model.

Results

The damage scores were (median, Q3-Q1): 1 (1-1) for Accuject, 1 (1-1) for Bluemixs, and 1 (1-1) for RayOne. There was no statistically significant difference in the damage scores between the study groups (P > 0.05). The outer cross-sectional vertical and horizontal diameters were 1.69 and 1.69 mm for Accuject, 1.69 and 1.69 mm for Bluemixs, and 1.70 and 1.71 mm for RayOne. Plunger tip areas were 0.78 mm2 for Accjuect, 0.74 mm2 for Bluemixs, and 0.43 mm2 for RayOne. Plunger tip area/inner cross-sectional area of the nozzle tip (%) was 31.2% for RayOne, 66.7% for Accuject, and 63.8% for Bluemixs. The tip angles for three injector models were 56° (Accuject), 56° (Bluemixs), and 44° (RayOne).

Conclusions

All the injector models showed mild to moderate damage to the nozzle tip after IOL implantation, even with smaller diameter tips. RayOne resulted in the lowest ratio between plunger tip area and inner cross-sectional area of the nozzle tip and a better distribution of damage categories than the other two groups. All three injector models had relatively small tip parameters. If smaller incisions are required in certain patients, smaller tip parameters should be considered.

Evaluation of Nozzle Tip Damage in Intraocular Lens Injectors with V-Shaped Notch

INTRODUCTION

Damage to the nozzle tips of intraocular lens (IOL) injectors has been associated with various adverse events and even IOL surface abnormalities after IOL implantation. In this study, nozzle tip damage of three different injector models with v-notched nozzle tips was systematically evaluated using our self-developed system - the Heidelberg Score for IOL injector damage.

METHODS

Nozzle tip damage was categorized into 6 grades: no damage (grade 0), slight scratches (1), deep scratches (2), extensions (3), cracks (4), and bursts (5). Each grade was assigned to a score of 0-5. In each IOL injector group, all IOLs were divided into 2 subgroups based on IOL power: +15 to +21D group and +21 to +26D group. The total scores for each group were the sum of scores for all injectors in this group. Further analysis was performed on the nozzle tip configuration and parameters in each injector model.

RESULTS

The median (Q1-Q3) for each injector group in group +15 to +21D was 1.5 (1-2) for Avansee, 4 (3-4) for iSert, and 4 (3-4) for multiSert. A statistically significant difference was found between Avansee and iSert (p < 0.001) as well as between Avansee and multiSert (p < 0.01) in terms of median scores. The median (Q1-Q3) for each injector group in group +21 to +26D was 1.5 (1-2) for Avansee, 4 (4-4) for iSert, and 3 (3-3.75) for multiSert. A statistically significant difference was found between Avansee and iSert in terms of median scores (p < 0.001). The outer cross-sectional diameters were 1.80 and 1.78 mm for Avansee, 1.70 and 1.69 mm for iSert, and 1.69 and 1.68 mm for multiSert. The radii of each notch-based circle were 0.21 mm (Avansee), 0.09 (iSert), and 0.06 (multiSert), respectively. The tip angles for three injector models were 48° (Avansee), 46° (iSert), and 37° (multiSert).

CONCLUSIONS

Avansee showed the least nozzle tip damage of all three groups. Compared with our earlier study using preloaded injectors with intact endpieces, all the injector groups with v-notched nozzle tips had more damage to the nozzle tip. It was found that the closer the notch of the nozzle tip was to the letter "V," the more damaged the nozzle tip was after IOL implantation.

Nozzle tip damage in three generations of intraocular lens injector models: an experimental laboratory study

PURPOSE

To assess the nozzle tip damage of IOL injectors in three generations from the same manufacturer using the self-developed system-the Heidelberg Score for IOL Injector Damage.

SETTING

David J Apple Center for Vision Research, Department of Ophthalmology, University Hospital Heidelberg, Heidelberg, Germany DESIGN: Experimental laboratory study METHODS: The nozzle tip damage of three injector models (Emerald, iTec, and Simplicity) was determined using the Heidelberg score for IOL injector damage. Damage to the nozzle tip was examined under a microscope and graded as follows: no damage (score 0), slight scratches (1), deep scratches (2), extensions (3), cracks (4) and bursts (5). The total scores for each injector system were the sum of scores for all injectors in this model. Total scores of the three injector systems were evaluated and compared. The nozzle tip parameters (diameters, tip angles) were also measured in each group.

RESULTS

The Emerald system achieved the highest total scores, while the other two systems achieved similar total scores. There was no statistically significant difference in the total scores between the study groups (P > 0.05). The outer cross-sectional diameters were 2.10 and 2.10 mm for Emerald, 1.80 and 1.78 mm for iTec, and 1.78 and 1.80 mm for Simplicity. The thickness of the nozzle tips was 0.13 mm (Emerald), 0.17 mm (iTec) and 0.17 mm (Simplicity). The tip angle for three injector models was 35° (Emerald), 45° (iTec), and 45° (Simplicity).

CONCLUSIONS

Although different injector models exhibited varying degrees of damage to the nozzle tip, all injector models generally showed relatively good results. Newer generations of IOL injector models tend to perform better in terms of nozzle tip damage after IOL implantation.

The course of surface deposits on a hydrophilic acrylic intraocular lens after implantation through a hexagonal cartridge

AIM

To evaluate the outcome of surface deposits that occurred during implantation of hydrophylic acrylic intraocular lenses (IOLs) through a hexagonal cartridge.

METHODS

Surface deposits were observed on the posterior surface of the ACR6D SE IOLs that were injected through a hexagonal cartridge filled with sodium hyaluronate 1%. All the patients were examined 1 day, 1 week, 1 month, 6 months and 1 year postoperatively. The location of the deposits was recorded and photographed. The patients were questioned about blurred vision, glare or halos.

RESULTS

Linear or curly deposits were detected on the posterior surface of the IOL in six patients. In four patients, the deposits were peripheral and were observed 1 week postoperatively. In two patients, the deposits were noticed immediately after implantation. In one eye, they were misinterpreted as a crack in the IOL's optic and were left in the eye. In the second patient the deposits were removed immediately after implantation with forceps. The deposits that were left after implantation (five eyes) did not resolve during 1 year of follow-up. None of the eyes developed abnormal inflammatory reaction. In three eyes the best-corrected visual acuity (BCVA) was 6/6. In the other three eyes the BCVA was 6/12. None of the patients experienced any visual disturbance.

CONCLUSIONS

Implantation of the ACR6D SE IOL through a hexagonal cartridge can lead to the formation of deposits on the posterior surface of the lens. The deposits do not resolve and may resemble a crack in the IOL. The deposits left on the IOL had no clinical relevance in our patients.

Linear deposits on the surfaces of intraocular lenses implanted through a hexagonal cartridge which mimic scratches/cracks on the lenses

AIM

To describe unique linear deposits on the surface of posterior chamber intraocular lenses (IOLs) occurring after implantation through a hexagonal cartridge.

METHODS

Five ACR6D SE IOLs (Corneal Laboratories, Pringy, France) were injected/implanted through hexagonal cartridges. Two of these were injected into a petri dish and the remaining three were inserted into the evacuated capsular bag of cadaver eyes. In addition, three other ACR6D SE IOLs were injected into a petri dish through round cartridges. The latter served as controls.

RESULTS

All lenses that were injected/implanted through the hexagonal cartridges demonstrated linear deposits on the posterior surface of the IOL optic component. The IOLs that were injected through the round cartridges had no deposits. All the hexagonal cartridges showed signs of internal cracking. None of the round cartridges were cracked.

CONCLUSION

Implantation of at least one IOL model, the ACR6D SE IOL, through a hexagonal cartridge can result in linear deposits on the posterior optical surface of the IOL. The shape of the cartridge appears to be a significant factor in causing the depositions.

Folding procedure for acrylic intraocular lenses

PURPOSE

To compare in vitro the effect of 2 standard methods of folding acrylic intraocular lenses (IOLs) on surface characteristics and bacterial adhesion.

SETTING

Eye Clinic and Department of Health-Microbiology Unit, University of Florence, Florence, Italy.

METHODS

To evaluate the effect of folding, 2 types of acrylic IOLs were not folded or folded with a forceps or an injector and then processed for scanning electron microscopy (SEM) examination. Bacterial adhesion was assessed using an ocular isolate of Pseudomonas aeruginosa. Nonfolded and folded IOLs were placed in test tubes containing the bacterial suspension for direct counting of viable adherent bacteria and for SEM.

RESULTS

The injector-folded IOLs did not show major alterations on the surface; 5 of the 9 forceps-folded IOLs showed marks or scratches in the profile of the optic. The mean number of viable adherent bacteria per area of IOL optic was 1082 (95% confidence interval [CI], 835-1330) in forceps-folded IOLs, 366 (95% CI, 192-359) in injector-folded IOLs, and 206 (95% CI, 123-289) in nonfolded IOLs. Scanning electron microscopy confirmed more surface irregularities on forceps-folded IOLs, with bacteria adherent preferentially on the surface scratches.

CONCLUSION

Forceps-folding provoked more surface irregularities, which probably make IOLs more susceptible to bacterial adhesion.