Unfolding characteristics of a new hydrophobic acrylic intraocular lens, and possible association with complications in triple procedures

Video analysis of optic-haptic-interaction during hydrophobic acrylic intraocular lens implantation using preloaded injectors

OBJECTIVE

To compare the optic-haptic interaction of different hydrophobic acrylic IOLs after using six preloaded injectors.

METHODS

We reviewed the video-recordings of procedures on a total of 388 eyes that underwent phacoemulsification and intraocular lens (IOL) implantation. For six preloaded injectors: multiSert (Hoya Surgical Optics) [System 1], TECNIS Simplicity (Johnson & Johnson Vision) [System 2], TECNIS iTec (Johnson & Johnson Vision) [System 3], AutonoMe (Alcon, Laboratories) [System 4], Bluesert (Carl Zeiss Meditec) [System 5], and Prosert (OphthalmoPro GmbH) [System 6], we noted in each case the time of IOL delivery and made a descriptive observation of IOL insertion and optic-haptic-interaction.

RESULTS

We defined standard haptic behavior where the haptics emerged "folded" from the injector and quickly recovered their pre-implantation appearance. The incidence where the leading haptic emerged in a deformed way for System 1 was 20%, System 2: 19%, System 3: 14%, System 4: 56%, System 5: 24% and System 6: 5%. For trailing haptic deformed behavior, the incidence was 36%, 6%, 4%, 8%, 18% and 2%, respectively for Systems 1 to 6. Optic-haptic adhesion occurred in 2% of cases for System 1, 44% for System 2, 52% for System 3, 48% for System 4, and 11% for System 6 (P < 0.05). Adhesion was not found with System 5.

CONCLUSIONS

We observed different deformed behavior for leading and trailing haptics in the six preloaded systems, some systems had as much as 52% optic-haptic adhesion.

Intraocular Lens Unfurling Time Exponentially Decays with Increased Solution Temperature

Purpose

Intraocular lens (IOL) unfurling can be a rate-limiting step in cataract surgery, limiting operative efficiency. Furthermore, inefficient unfurling has important implications for clinical outcomes. We examine the effects of solution temperature on IOL unfurling time using three in vitro models of the ocular environment.

Methods

IOLs were injected into a 6-well plate filled with balanced salt solution (BSS), dispersive ophthalmic viscoelastic device (OVD), or cohesive OVD. Experiments were also performed in a plastic eye filled with dispersive or cohesive OVD. IOL unfurling time was recorded against the temperature of the respective solution.

Results

IOL unfurling time decayed exponentially as solution temperature increased in all experiments, including the BSS-filled 6-well plate, the OVD-filled 6-well plate, and the OVD-filled plastic eye. IOLs failed to unfurl within 10 min at 10°C, below the glass transition temperature of the tested IOLs. Increasing solution temperature from 20°C to 30°C decreases IOL unfurling by greater than 2 min. Further heating to 40°C did not significantly decrease IOL unfurling time.

Conclusion

Increased solution temperature rapidly decreases IOL unfurling time in vitro. IOLs do not unfurl within a clinically acceptable timeframe at or below their glass transition temperature. Increased BSS and/or OVD temperature may be a potential method to decrease IOL unfurling time in cataract surgery. However, future research is needed to elucidate potential consequences of warmed BSS and/or OVD on post-operative outcomes. This study demonstrates the potential for temperature regulation to decrease cataract surgery operative time and provides preliminary evidence to justify future clinical validation of this relationship.

Posterior Vault Distance of Ciliary Sulcus-Implanted Three-piece Intraocular Lenses According to Ciliary Sulcus Diameter

PURPOSE

To investigate the correlation among preoperative biometry data, postoperative ciliary sulcus diameter, posterior vault distance, and effective lens position of ciliary sulcus-implanted intraocular lenses (IOLs).

DESIGN

Retrospective interventional case series.

METHODS

Twenty-six eyes of 26 patients underwent phacoemulsification with implantation of a ZA9003 IOL (Abbott Medical Optics Inc, Santa Ana, California, USA) in the ciliary sulcus. We analyzed correlations among preoperative biometry data and ultrasound biomicroscopy measurements, ciliary sulcus diameter, posterior vault distance, and effective lens position. Regression analyses were performed to identify which combination of preoperative biometry data, average corneal power (keratometry [K]), anterior chamber depth (ACD), and axial length (AL) was best for predicting effective lens position.

RESULTS

The sulcus diameter was shorter in eyes that had a steep cornea and shorter AL. The posterior vault distance was negatively correlated with sulcus diameter in subjects who had shorter postoperative time intervals (≤24 months) (R² = 0.336 and P = .038). The posterior vault distance decreased with each passing postoperative month (R² = 0.158 and P = .045). The R² value for predicting the effective lens positions of sulcus-implanted IOLs based on the entire average K, ACD, and AL was higher than those based on parts of these values.

CONCLUSIONS

The effective lens position of sulcus-implanted IOLs can be affected by sulcus diameter, and lens position can change, especially in the early postoperative period. We recommend using the entire average K, ACD, and AL to predict the effective position of sulcus-implanted IOLs.

Combined 25-gauge vitrectomy and cataract surgery with toric intraocular lens with idiopathic epiretinal membrane

PURPOSE

To evaluate the stability of axis rotation, astigmatism correction, and improvement in uncorrected distance visual acuity (UDVA) up to 6 months postoperatively using an astigmatism-correcting intraocular lens (IOL) in a 25-gauge transconjunctival sutureless vitrectomy combined with cataract surgery.

SETTING

Department of Ophthalmology, Kagawa University Faculty of Medicine, Kagawa, Japan.

DESIGN

Prospective nonrandomized interventional study.

METHOD

Eyes with a preoperative corneal cylinder of more than 0.75 diopter (D) had a triple procedure for idiopathic epiretinal membrane (ERM) using an Acrysof IQ toric IOL. Outcome measures were the amount of IOL axis rotation up to 3 months postoperatively, UDVA, corrected distance visual acuity, and corneal and refractive astigmatism up to 6 months postoperatively. A comparison was performed between patients with a target postoperative spherical refraction of emmetropia (toric emmetropic group) and patients who previously had a triple procedure for idiopathic ERM using a nontoric IOL (control group).

RESULTS

The mean IOL axis rotation from the end of surgery until 3 months postoperatively was 3.67 degrees ± 3.13 (SD). Six months postoperatively, the mean corneal and refractive cylinders were 1.32 ± 0.61 D and 0.51 ± 0.31 D, respectively, showing a significant difference (P<.0001, paired t test). In addition, the mean UDVA was significantly improved 6 months postoperatively in the control and toric emmetropic group (0.57 logMAR versus 0.35 logMAR) (P=.028), although the toric group was more improved than the control group.

CONCLUSION

In vitrectomy (triple procedure) for idiopathic ERM with a toric IOL, postoperative IOL axis stability was similar to that reported for cataract surgery alone. Furthermore, the UDVA was better than with implantation of a spherical IOL.