Éva Juhász

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. Financial Disclosure Drs. Nagy, T. Juhász, and Slade are consultants to Alcon‐Lensx, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

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.

Expression of Tight Junction Molecules in Breast Carcinomas Analysed by Array PCR and Immunohistochemistry

In the past few decades an enormous amount of data became known to clarify the molecular composition and architecture of tight junctions (TJs). Despite the efforts, the expression and function of several TJ genes and proteins in breast carcinoma are still not known and some of the data are contradictory. The expression of forty-four TJ associated genes was examined at mRNA level in eighteen invasive ductal breast carcinoma samples and corresponding normal breast tissues by using low density array PCR. Expressions of claudins (CLDNs) 5, 10, 16, 17, and 18, and ZO-1, ZO-2 were evaluated by immunohistochemistry as well. Using immunohistochemical phenotype as a surrogate for the genetic subtype, 11 luminal A, 3 luminal B, 3 triple negative and one HER2+ cases were included. Ten genes were significantly downregulated in tumors compared with normal breast tissues (CLDNs 5, 10, 16, 18, 19, CTNNAL1, JAM-B, ZO-1, ZO-2 and PARD3), whereas one gene (CLDN17) was significantly up-regulated in tumors when compared with normal breast. At protein level CLDNs 5, 10, 16, 18, ZO-1 and ZO-2 were downregulated in tumors as compared with normal breast tissue. CLDN17 showed variable expression in tumor tissues in comparison to normal breast. In the single HER2+ tumor when compared with the other subtypes CLDNs 5, 16, 17, 18, CTNNAL1, JAM-B, ZO-1, ZO-2 and PARD3 genes were found to be upregulated. We found altered TJ genes and proteins whose expression has not yet been associated with breast carcinoma. Our findings show a tendency of TJ genes and proteins to be downregulated in breast cancer. Further studies are necessary to examine whether the downregulation of the above mentioned TJ associated genes and proteins may contribute to the malignant progression of invasive ductal breast carcinomas.

Laser refractive cataract surgery with a femtosecond laser after penetrating keratoplasty: case report.

Laser Refractive Cataract Surgery With a Femtosecond Laser After Penetrating Keratoplasty: Case Report Cataract surgery after corneal transplant must minimize endothelial cell damage because postoperative transplant cell counts are lower than those of normal corneas. As the femtosecond laser was successfully introduced in cataract surgery,1,2 we applied this technology in an eye that had a previous penetrating corneal transplant. A 33-year-old man had a 7.0-mm diameter penetrating keratoplasty in his right eye 6 years prior to presentation. He later developed posterior polar cataract. The cornea was clear and corrected distance visual acuity (CDVA) was 20/40. Femtosecond laser–assisted cataract surgery (Alcon LenSx, Aliso Viejo, California) was performed as described previously.1,2 The corneal scar was peripheral to the planned capsulotomy. Centration was assessed using the pupillary edge. A 4.8-mm capsulorrhexis was performed with the femtosecond laser and the nucleus was liquefi ed. Corneal wounds were created with a 2.8-mm and 15° blade so as not to interfere with the transplant scar. The anterior chamber was fi lled with viscoelastic material, and the edge of the capsulorrhexis was identifi ed with a cystotome and removed with a capsulorrhexis forceps. After hydrodissection, the lens nucleus and cortex were aspirated with the irrigation-aspiration handpiece. A 12.00-diopter (D) hydrophobic acrylic posterior chamber intraocular lens (Acrysof; Alcon Laboratories Inc, Ft Worth, Texas) was implanted in the capsular bag. On postoperative day 1, CDVA was 20/200 because of slight corneal edema, which improved to 20/25 over the next 3 months. Subjective refraction was stable at 1.25 D sphere and 6.00 D cylinder at 1-year followup, with CDVA of 20/20. Corneal thickness measured with a Scheimpfl ug camera (Pentacam HR; Oculus Optikgeräte GmbH, Wetzlar, Germany) was 609 μm preoperatively and 598 μm 1 month postoperatively. We report the fi rst patient having successful laser refractive cataract surgery after penetrating keratoplasty. The curved interface aligned perfectly along the transplanted and donor cornea. Optical coherence tomography identifi ed the scar line of the transplant and the scar did not interfere with the laser capsulotomy. The corneal incisions were created manually because of the peripheral localization of the transplant scar. As reported previously,1 the use of a femtosecond laser may minimize the ultrasound energy required to remove the nucleus, thereby preserving endothelial cells in postoperative transplant corneas. Graft failure following phacoemulsifi cation and intraocular lens implantation is reported to be between 3% and 8%.3,4 Endothelial cell loss related to ultrasound use is usually markedly higher in transplanted corneas than in normal, unoperated eyes.5 In our case, most likely due to the use of the femtosecond laser to liquefy the nucleus, no ultrasound was required to remove the lens and endothelial cell count did not change up to 1 year after surgery. Zoltán Z. Nagy, MD, DSC Ágnes I. Takács, MD Tamás Filkorn, MD Éva Juhász, MD Gábor Sándor, MD Andrea Szigeti, MD Budapest, Hungary Michael C. Knorz, MD Mannheim, Germany

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.

Evaluation of intereye corneal asymmetry in patients with keratoconus. A Scheimpflug imaging study

Purpose To assess the correlation between keratoconus severity and intereye asymmetry of pachymetric data and posterior elevation values and to evaluate their combined accuracy in discriminating normal corneas from those with keratoconus. Methods This study included 97 patients: 65 subjects with bilateral normal corneas (NC) and 32 with keratoconus (KC). Central corneal thickness (CCT), thinnest corneal thickness (ThCT) and posterior elevation (PE) at the thinnest point of the cornea were measured in both eyes using Scheimpflug imaging. Intereye asymmetry and its correlation with keratoconus severity were calculated for each variable. The area under the receiver operating characteristic curve (AUROC) was used to compare predictive accuracy of different variables for keratoconus. Results In normal eyes, intereye differences were significantly lower compared with the keratoconus eyes (p<0.001, for CCT, ThCT and PE). There was a significant exponential correlation between disease severity and intereye asymmetry of steep keratometry (r2 = 0.55, p<0.001), CCT (r2 = 0.39, p<0.001), ThCT (r2 = 0.48, p<0.001) and PE (r2 = 0.64, p<0.001). After adjustment for keratoconus severity, asymmetry in thinnest pachymetry proved to be the best parameter to characterize intereye corneal asymmetry in keratoconus. This variable had high accuracy and significantly better discriminating ability (AUROC: 0.99) for KC than posterior elevation (AUROC: 0.96), ThCT (AUROC: 0.94) or CCT (AUROC: 0.92) alone. Conclusions There is an increased intereye asymmetry in keratometry, pachymetry and posterior corneal elevation values in keratoconic patients compared to subjects with normal corneas. Keratoconus patients with more severe disease are also more asymmetric in their disease status which should be taken into account during clinical care.

Scheimpflug imaging for long-term evaluation of optical components in Hungarian children with a history of preterm birth.

PURPOSE To determine ocular geometry and refraction in children with a history of preterm birth, and compare them to age-matched full-term children. METHODS In a prospective case-control study, 50 eyes of 27 premature patients 7 to 14 years of age were evaluated with Scheimpflug camera after cycloplegia. Age-matched full-term children comprised the control group (68 eyes of 34 children). All of the eligible eyes had a normal-appearing posterior pole. Anterior segment parameters such as keratometry, anterior chamber volume or thickness, and lens thickness were measured. Corneal thickness, lower- and higher-order aberrations refractive errors of the cornea (root mean square of lower- and higher-order aberrations: RMS LOA, RMS HOA) were also assessed and exported for further analysis. RESULTS In the premature eyes, anterior chamber depth was marginally smaller (P = .06), the lens was significantly thicker (P = .03), and axial length was significantly shorter (P < .001). Scheimpflug imaging showed a significant difference in corneal RMS (P = .03) and an increase in corneal RMS HOA (P = .002) in the premature group. Preterm birth showed significant impact on axial length (P < .01) and lens thickness (P = .05); at the same time, anterior chamber depth was more influenced by retinopathy of prematurity stage (P = .01). Laser treatment showed marginally significant impact (P = .06) on anterior chamber depth. CONCLUSIONS In premature eyes with or without mild retinopathy of prematurity, anterior segment anatomy is slightly different and they have more higher-order corneal aberrations compared to the eyes of term-born children.

Changes of Corneal Topography Indices After CXL in Progressive Keratoconus Assessed by Scheimpflug Camera

PURPOSE To evaluate the accuracy of Scheimpflug camera topography indices in detecting the therapeutic effect of corneal collagen cross-linking (CXL) on progressive keratoconus in the long term. METHODS Fifty eyes of 25 patients with keratoconus were enrolled. CXL was performed in 25 eyes with progressive keratoconus (CXL group) and 25 fellow eyes with nonprogressive keratoconus served as controls. Thinnest corneal thickness, anterior keratometry (flat, steep), and keratoconus indices were measured with Scheimpflug camera before and 12 to 25 months after CXL. Regression analysis was used to evaluate the influence of corneal thickness and follow-up time on flattening effect of CXL. RESULTS At baseline, steep keratometric values were significantly higher and thinnest corneal thickness values were lower in the CXL group (P = .027, .034), parallel with increased values of keratoconus indices: index of surface variance (P = .013), index of vertical asymmetry (P = .038), keratoconus index (P = .019), center keratoconus index (P = .039), index of height asymmetry (P = .037), index of height decentration (P = .0016), and radius minimum (P = .008). After adjustment for thinnest corneal thickness and follow-up time, CXL showed significant flattening effect expressed by changes in radius minimum (P < .001), index of surface variance (P = .03), keratoconus index (P = .006), center keratoconus index (P = .03), and index of height asymmetry (P = .026). Thinnest corneal thickness had significant influence on changes of index of surface variance (P = .049), index of vertical asymmetry (P = .01), and center keratoconus index (P = .03). Follow-up time showed no significant influence in any models (P > .05). CONCLUSIONS Topographic indices indicate corneal flattening after CXL in the long term. Monitoring keratoconus index and index of height asymmetry should be the preferred choice in daily clinical practice because changes in values of these indices are independent from initial corneal thickness.

Analysis of Planned and Postoperatively Measured Flap Thickness After LASIK Using the LenSx Multifunctional Femtosecond Laser System

PURPOSE To evaluate LASIK corneal flaps using a multifunctional femtosecond laser suitable for cataract and corneal surgery (LenSx; Alcon Laboratories, Inc., Aliso Viejo, CA) and to compare the planned and postoperatively measured flap thickness using an anterior segment optical coherence tomography device (AS-OCT). METHODS Twenty patients (38 eyes) diagnosed as having myopia and myopic astigmatism were enrolled. LASlK was performed using the LenSx femtosecond laser for intracorneal flaps and the Wavelight Allegretto 400 excimer laser (Alcon Laboratories, Inc.) for intra- stromal photoablation. Desired flap thickness and diameter were 140.0 + 0.0 pm and 8.5 + 0.0 mm, respectively, whereas mean ablation depth and diameter of the excimer laser treatment were 67.9 ± 24.18 pm and 6.5 ± 0.08 mm, respectively. Entered data of the LenSx femtosecond laser were used to determine desired flap thickness, whereas AS-OCT (RTVue; Optovue, Inc., Fremont, CA) was used to measure flap thickness postoperatively. The Wilcoxon signed-rank test, dependent paired t test, and Friedman test were used for comparison of dependent and repeated measures. RESULTS There was no statistically significant difference in the planned and postoperatively measured flap thickness (140.0 ± 0.0 vs 140.28 _ 8.0 pm; P = .4067). Interfaces of the flaps had even surfaces according to the images and calculations on the AS-OCT device (P = .058). CONCLUSIONS Application of this multifunctional femtosecond laser performing LASIK proved to be a safe and effective method regarding predictability of flap thickness.

Wavefront properties of the anterior and posterior corneal surface after photorefractive keratectomy.

Purpose: The aim of this study was to evaluate the balance and changes of corneal higher order aberrations (HOAs) after photorefractive keratectomy (PRK). Methods: Myopic and myopic–astigmatic patients (89 eyes of 48 patients) were enrolled in this study. A PRK was performed using an Asclepion Meditec MEL 80 G flying-spot excimer laser. The mean ablation depth and diameter were 76.78 &mgr;m (±19.40 &mgr;m) and 6.0 mm (±0.06 mm), respectively. Before and 1 year after the surgery, uncorrected and best spectacle-corrected visual acuities were determined. Wavefront aberrations of the anterior [root mean square (RMS)-HOA anterior], posterior (RMS-HOA posterior), and total cornea (RMS-HOA total) were measured using a Scheimpflug Camera. Linear piecewise regression analysis was used for correlations between the ablation depth and aberration of the anterior corneal surface. The follow-up time was 1 year. Results: At baseline, RMS-HOA anterior proved to be significantly higher compared with RMS-HOA total (P < 0.001). After the PRK was performed, the RMS-HOA anterior (P < 0.001) and RMS-HOA total values (P < 0.001) increased significantly; however, RMS-HOA posterior values (P = 0.12) remained stable. Above an ablation depth of 76.78 &mgr;m, the RMS-HOA anterior increased 2.4-fold. Uncorrected and best spectacle-corrected visual acuities were 1.0 (20/20) in 95.5% and 98.8% of the patients 1 year postoperatively. Conclusions: Aberrations of the posterior corneal surface seem to compensate for wavefront alterations of the anterior cornea, decreasing the amount of wavefront error regarding the total cornea in myopic patients. PRK induced increased HOAs with respect to the anterior corneal surface; however, the posterior surface remained stable. The increase in the HOAs was measured to be significantly larger above 76.78 &mgr;m photoablation depth.