One-Day Use of Preoperative Topical Nonsteroidal Anti-Inflammatory Drug Prevents Intraoperative Prostaglandin Level Elevation During Femtosecond Laser-Assisted Cataract Surgery.

PURPOSE: To determine if pretreatment with topical nonsteroidal anti-inflammatory drug (NSAID) prior to femtosecond laser-assisted cataract surgery (FLACS) prevents intraoperative prostaglandin level elevation as a potential risk factor of postoperative complications. PATIENTS AND METHODS: Thirty-six patients with clinically significant cataract and without any concomitant general or ophthalmic disease were enrolled into the three age-matched groups of the study. The mean age of the patients was 62.3 ± 13.1 years. The first group of patients underwent traditional phacoemulsification (Control group), on the second group of patients FLACS was performed, and the third group of patients received topical 0.1% nepafenac pretreatment for 1one day prior to FLACS. Before the phacoemulsification part of the cataract surgery, approximately 110 µL of aqueous humor was collected in all groups. Total prostaglandin concentrations of the collected aqueous humor samples were evaluated by enzyme immunoassay (EIA). RESULTS: The mean of the total prostaglandin concentrations of the aqueous humor samples was 208.8 ± 140.5 pg/mL in patients in the control group, 1449.1 ± 1019.7 pg/mL in the FLACS group (p > 0.001), and 92.2 ± 51.7 pg/mL in the group pretreated with topical NSAID before the FLACS (p > 0.001 compared to FLACS; p > 0.01 compared to control), respectively. CONCLUSIONS: FLACS surgery increases intracameral prostaglandin concentration. However, using preoperative 1-day-long nonsteroid anti-inflammatory drops prior to FLACS, this intraoperative increase diminishes. Our study raises the possibility that NSAID pretreatment may be routinely administered before FLACS cataract surgeries to achieve a further decrease in the potential complications of increased total prostaglandin concentration during FLACS surgeries.

Evaluation of the mechanical properties of the anterior lens capsule following femtosecond laser capsulotomy at different pulse energy settings.

PURPOSE: To evaluate and compare the mechanical properties of anterior capsule opening performed with femtosecond laser capsulotomy at different energy settings in ex vivo porcine anterior lens capsule specimens. METHODS: Twenty-five fresh porcine eyes per group were included in the study. Femtosecond laser capsulotomy was performed with three different pulse energy levels: 2 µJ (low energy group), 5 µJ (intermediate energy group), and 10 µJ (high energy group). The capsule openings were stretched with universal testing equipment until they ruptured. The morphologic profile of the cut capsule edges was evaluated using scanning electron microscopy. RESULTS: The high energy group had significantly lower rupture force (108 ± 14 mN) compared to the intermediate energy group (118 ± 10 mN) (P < .05) and low energy group (119 ± 11 mN) (P < .05), but the difference between the intermediate energy and low energy groups was not significant (P = .9479). The high energy group had significantly lower circumference stretching ratio (144% ± 3%) compared to the intermediate energy group (148% ± 3%) (P < .05) and low energy group (148% ± 3%) (P < .05), but the difference between the intermediate energy group and low energy group was not significant (P = .9985). Scanning electron microscopy images showed that the edge was only serrated with low and intermediate energy, but additional signs of collagen melting and denaturation were observed at high energy. CONCLUSIONS: Anterior capsule openings created at a high energy level were slightly weaker and less extensible than those created at low or intermediate levels, possibly due to the increased thermal effect of photo-disruption.

[Results of femtosecond laser-assisted cataract surgery using the new 2.16 software and the SoftFit® Patient Interface]. / A femtoszekundumlézer-asszisztált szürkehályog-mutét eredményei az új 2.16-os szoftverrel és a módosított SoftFit® páciensi felszínnel.

INTRODUCTION: Femtosecond laser-assisted cataract surgery improved the results of cataract surgeries. AIM: Outcome analysis of femtosecond laser-assisted cataract surgery using the novel 2.16 software and the SoftFit(®) Patient Interface. METHOD: The novel software and the newly developed Patient Interface were used in 100 eyes of 100 patients. RESULTS: Length of femtosecond laser pretreatment decreased to 45-60 seconds. The smaller size of the new patient interface resulted in easier docking even on pediatric eyes. Suction force used for docking decreased from 40-50 mmHg to 16-20 mmHg. Incidence rate of subconjunctival suffusion decreased from 40% to 15-20% and its clinical severity was reduced, too. No corneal microfolds evolved, thus the incidence rate of the free-floating capsulotomies increased from 30% to 97%. The total energy of femtosecond laser pretreatment was decreased by almost 50%. Corneal wounds had the desired structure, and they were easy to open and closed precisely. CONCLUSIONS: The SoftFit(®) patient interface and the novel software widened the possible uses of the femtosecond laser-assisted cataract surgery, e.g. in pediatric ophthalmology. Innovations improved the safety and the predictability of the method.

Comparison of the mechanical properties of the anterior lens capsule following manual capsulorhexis and femtosecond laser capsulotomy.

PURPOSE: To evaluate and compare the mechanical properties of anterior capsule openings performed with the continuous curvilinear capsulorhexis (CCC) technique and femtosecond laser capsulotomy (FLC) in ex vivo porcine lens capsule specimens. METHODS: Fresh porcine eyes were included in the study (CCC group, n = 50; FLC group, n = 30). The capsule openings were stretched with universal testing equipment until they ruptured. The rupture force and circumference stretching ratio were evaluated. The morphologic profile of the cut capsule edges was evaluated using scanning electron microscopy (SEM). RESULTS: The average rupture force was higher in the CCC group (median: 155 mN; interquartile range [IQR]: 129 to 201 mN; range: 71 to 294 mN) than in the FLC group (median: 119 mN; IQR: 108 to 128 mN; range: 91 to 142 mN) (P < .01, Mann-Whitney U test). The average circumference stretching ratio in the CCC group was greater (median: 150%; IQR: 146% to 156%; range: 136% to 161%) than in the FLC group (median: 148%; IQR: 145% to 150%; range: 141% to 154%) (P = .0468, Mann-Whitney U test). When less than 71 mN, no capsular tear occurred in either group. When less than 91 mN, no capsular tear occurred in the FLC group, whereas at 91 mN, the probability of capsular tears was 9% for the CCC group. SEM examination found that the CCC group had smooth edges, whereas those of the FLC group were gently serrated. CONCLUSIONS: According to the current results in a porcine eye model, FLC had less average resistance to capsule tear than CCC, but the weakest openings were seen in the CCC group.

Complications of femtosecond laser-assisted cataract surgery.

PURPOSE: To analyze complications of femtosecond lasers used for cataract surgery. SETTING: Department of Ophthalmology Semmelweis University, Budapest, Hungary. DESIGN: Retrospective analysis. METHODS: Intraoperative complications of the first 100 femtosecond laser-assisted (Alcon-Lensx, Inc.) cataract surgeries were collected. Possible complications of femtosecond capsulotomies and their management were also assessed. RESULTS: The complications were as follows: suction break (2%), conjunctival redness or hemorrhage (34%), capsule tags and bridges (20%), anterior tear (4%), miosis (32%), and endothelial damage due to cut within the endothelial layer (3%). There were no cases of capsule blockage or posterior capsule tear. During the learning curve, there was no complication that would require vitrectomy. All complications occurred during the first 100 cases. CONCLUSIONS: Femtosecond laser cataract surgery had a learning curve during the first 100 cases. With cautious surgical technique, the complications can be avoided. The femtosecond laser-assisted method was efficient and safe for cataract surgery.

Anterior segment OCT imaging after femtosecond laser cataract surgery.

PURPOSE: To report the anterior segment imaging characteristics after femtosecond laser assisted cataract surgery. METHODS: Cataract surgery was performed with the LenSx femtosecond laser (Alcon-LenSx Inc., Aliso Viejo, CA) in 40 eyes of 40 patients. The laser was programmed to perform a 4.5-mm capsulorhexis, a cross-pattern fragmentation of the nucleus, a 2.8-mm main incision, and a 1.0-mm side-port incision. The anterior segment was then analyzed using the Visante OCT anterior segment program (Zeiss-Meditec AG, Jena, Germany). RESULTS: The preoperatively set treatment parameters correlated well with the achieved results. For the capsulorhexis, the femtosecond laser cut was programmed to start 350 µm behind the anterior lens capsule and OCT measured 377 ± 55.3 µm. Nucleus fragmentation was programmed to start 750 µm in front of the posterior capsule and end 550 µm behind the anterior capsule, and OCT measured 794 ± 111 and 568 ± 147 µm, respectively. The diameter of the capsulorhexis measured by OCT was 4.54 ± 0.2 mm, compared to the 4.5 mm programmed. CONCLUSIONS: Anterior segment OCT imaging was able to detect the tissue changes within the lens after femtosecond laser capsulorhexis and nucleus fragmentation. The measured values correlated well with the planned treatment parameters.

Comparison of long-term visual outcome and IOL position with a single-optic accommodating IOL After 5.5- or 6.0-mm Femtosecond laser capsulotomy.

PURPOSE: To evaluate the long-term visual outcome and intraocular (IOL) position parameters with a single-optic accommodating IOL after 5.5- or 6.0-mm femtosecond laser capsulotomy. METHODS: This prospective, randomized, pilot study comprised 17 eyes from 11 patients (7 men) with a mean age of 65.82±10.64 years (range: 51 to 79 years). All patients received a Crystalens AT-50AO (Bausch & Lomb) accommodating IOL after femtosecond laser refractive cataract surgery using either a 5.5-mm capsulotomy (5.5-mm group; 9 eyes) or 6.0-mm capsulotomy (6.0-mm group; 8 eyes). Near and distance visual acuities, manifest refraction spherical equivalent (MRSE), and IOL tilt and decentration were evaluated 1 year postoperatively. RESULTS: No significant differences were noted between groups for postoperative uncorrected distance visual acuity, uncorrected near visual acuity, distance-corrected near visual acuity, and MRSE. Vertical and horizontal tilt were significantly higher in the 6.0-mm group than in the 5.5-mm group (P=.014 and P=.015, respectively). No significant difference was observed between groups regarding IOL decentration. CONCLUSIONS: A 5.5-mm capsulotomy created with a femtosecond laser is associated with less IOL tilt and therefore may be superior to a 6.0-mm capsulotomy when implanting a single-optic accommodating IOL.

Central corneal volume and endothelial cell count following femtosecond laser-assisted refractive cataract surgery compared to conventional phacoemulsification.

PURPOSE: To compare the effect of conventional phacoemulsification and femtosecond laser-assisted cataract surgery on the cornea using Scheimpflug imaging and noncontact specular microscopy. METHODS: In each group, 38 eyes (38 patients) underwent cataract surgery using either femtosecond laser-assisted (Alcon LenSx laser) (femtolaser group) or conventional phacoemulsification (phaco group). Central corneal thickness, 3-mm corneal volume, and Pentacam Nucleus Staging (PNS) were determined by a rotating Scheimpflug camera (Pentacam HR, Oculus Optikgeräte GmbH), and the volume stress index was calculated at 1 day and 1 month postoperatively. Endothelial cell count was measured by noncontact specular microscopy preoperatively, 1 day, 1 week, and 1 month postoperatively. RESULTS: Central corneal thickness was significantly higher in the phaco group (607±91 µm) than in the femtolaser group (580±42 µm) on day 1, but did not differ significantly preoperatively and at 1 week and 1 month. Volume stress index at day 1 was significantly lower in the femtolaser group than in the phaco group (P<.05) but did not differ significantly at 1 month. Multivariate regression analysis showed that the type of surgery had a significant effect on central corneal thickness. CONCLUSIONS: Femtosecond laser-assisted cataract surgery causes less corneal swelling in the early postoperative period and may cause less trauma to corneal endothelial cells than manual phacoemulsification.

Internal aberrations and optical quality after femtosecond laser anterior capsulotomy in cataract surgery.

PURPOSE: To compare ocular and internal aberrations after femtosecond laser anterior capsulotomy and continuous curvilinear capsulorrhexis in cataract surgery. METHODS: In this prospective study, anterior capsulotomy was performed during cataract surgery with an intraocular femtosecond (FS) laser (Alcon LenSx Inc) in 48 eyes. As a control group, continuous curvilinear capsulorrhexis (CCC) was performed in 51 eyes. Wavefront aberrometry, corneal topography, and objective visual quality were measured using the OPD-Scan (NIDEK Co Ltd). Vertical and horizontal tilt, coma, and visual quality metrics were evaluated separately to determine whether the source of aberrations was ocular or internal. Main outcome measures included postoperative residual refraction, uncorrected and corrected visual acuities, ocular and internal aberrations, Strehl ratio, and modulation transfer function (MTF). RESULTS: No statistically significant differences were noted between the FS and CCC groups, respectively, in postoperative sphere (-0.60 ± 1.50 vs -0.50 ± 1.40 diopters [D]), postoperative cylinder (1.30 ± 1.01 vs 1.10 ± 1.10 D), uncorrected distance visual acuity (0.86 ± 0.15 vs 0.88 ± 0.08), or corrected distance visual acuity (0.97 ± 0.08 vs 0.97 ± 0.06). The FS group had significantly lower values of intraocular vertical tilt (-0.05 ± 0.36 vs 0.27 ± 0.57) and coma (-0.003 ± 0.11 vs 0.1 ± 0.15), and significantly higher Strehl ratios (0.02 ± 0.02 vs 0.01 ± 0.01) and MTF values at all measured cycles per degree, compared to the CCC group. CONCLUSIONS: Capsulotomy performed with an intraocular FS laser induced significantly less internal aberrations measured by the NIDEK OPD-Scan aberrometer compared to eyes that underwent CCC, which may result in better optical quality after the procedure.

Comparison of intraocular lens decentration parameters after femtosecond and manual capsulotomies.

PURPOSE: To evaluate a laser technique and manual technique to perform capsulorrhexis in cataract eyes. METHODS: Anterior capsulotomy was performed with an intraocular femtosecond laser (LenSx Lasers Inc) in 54 eyes (FS group) and manual continuous curvilinear capsulorrhexis was performed in 57 eyes (CCC group). Circularity and area of capsulotomy and IOL decentration were measured using Photoshop CS4 Extended (Adobe Systems Inc) 1 week after surgery. Average keratometry, axial length, and preoperative anterior chamber depth were examined with the Lenstar LS 900 (Haag-Streit AG). RESULTS: No statistically significant differences were noted between groups in axial length, preoperative refractive state, and in the area of capsulotomy. Circularity values were significantly better in the FS group (P=.032). We found incomplete overlap of capsulotomies in 28% of eyes in the CCC group and 11% in the FS group (P=.033). Significant correlations were noted between axial length and area of capsulotomy, and between average keratometry and area of the capsulotomy in the CCC group (R=0.278, P=.036; and R=-0.29, P=.033, respectively), but both did not correlate in the FS group (P>.05). In the CCC group, the pupillary area correlated significantly with the area of the capsulotomy (R=0.27, P=.039). Significant correlation was noted between IOL decentration and axial length in the CCC group (R=0.30, P=.026), but there was no correlation in the FS group (P>.05). CONCLUSIONS: Femtosecond laser capsulorrhexis was more regularly shaped, showed better centration, and showed a better intraocular lens/capsule overlap than manual capsulorrhexis.

Corneal density with the Pentacam after photorefractive keratectomy.

PURPOSE: To measure corneal density and evaluate corneal haze in unoperated eyes and in eyes after photorefractive keratectomy (PRK). METHODS: Forty-nine patients (91 eyes) who underwent PRK and 48 control patients (76 unoperated eyes) were measured with the densitometry program of the Pentacam Scheimpflug imaging system (Oculus Optikgeräte GmbH) (0=no clouding, 100=tissue completely opaque). Eyes were categorized as myopic or hyperopic (myopia group and hyperopia group), with subgroups defined as unoperated (unoperated myopia group and unoperated hyperopia group), postoperative clear corneas (clear cornea myopia group and clear cornea hyperopia group), and postoperative with haze (myopia haze group and hyperopia haze group). The ANOVA option of the Statistica 8.1 program package (StatSoft Inc) was used to compare subgroups. RESULTS: Maximum density of postoperative corneas with haze (myopia haze group, 46.2±16.2; hyperopia haze group, 50.2±25.8) was higher than in postoperative clear corneas (clear cornea myopia group, 29.9±8.7; clear cornea hyperopia group, 22.9±3.1), but maximum corneal density in the latter subgroups showed no difference compared with unoperated controls (unoperated myopia group, 25.1±2.4; unoperated hyperopia group, 22.8±3.2). Differences among subgroups were not found outside the 6-mm diameter ablation zone. In hazy myopic corneas, there was a strong decreasing density trend from the apex to the 3-mm radius (P<.001, R=-0.5), which continued towards the periphery at 4.5 mm (P=.019, R=-0.21). Hyperopic mild hazy corneas showed a density increase from the apex to 3 mm (P<.001, R=0.4), followed by a decrease towards the periphery (P<.01, R=-0.4). CONCLUSIONS: The densitometry program of the Pentacam can provide a useful objective measure of postoperative and other mild corneal haze.