Andrea Gyenes

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.

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.

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.

A szaruhártya felszíni hőmérséklete és légáramlási viszonyainak alakulása refraktív célú lézeres beavatkozás közben három különböző típusú és ismétlési frekvenciájú excimer lézerberendezésnél

Absztrakt Bevezetes: A cornea torőerejenek excimer lezerrel tortenő modositasa kozben a termikus viszonyok alakulasa fontos tenyező lehet a sebgyogyulas es a hosszu tavu eredmenyek szempontjabol. Celkitűzes: A tanulmany celja a refraktiv műtet soran a szaruhartya felszini hőmersekletenek vizsgalata harom kulonboző lezerplatformnal Modszer: A vizsgalatot 90 beteg egyik kezelt szemen vegeztek, amelyeken Carl Zeiss MEL 70 es MEL 80, illetve Wavelight Allegretto tipusu lezerrel tortent photorefractiv keratectomia kezeles. EBRO TLC 730 infravoros hőmerővel vegeztek merest kozvetlenul a hameltavolitas előtt, valamint kozvetlenul a kezeles előtt es utan. A betegek atlageletkora 25,5 ± 3 ev volt. Minden fenytoresi hiba myopias vagy myop astigmias volt, atlaguk –3,2 ± 0,8 Dpt volt. Eredmenyek: A felszini cornea hőmersekletenek alakulasaban statisztikailag szignifikans kulonbseg volt a MEL 80 es a masik ket tipusu lezer kozott. Kovetkeztetesek: A lezerkeszulekek szoveti gőzok eltavolitasara szolgalo elszivorendszer...

Crosslinking kezelés hatása a szaruhártya hámosodására

INTRODUCTION AND AIM To analyse the effect of crosslinking (CXL) on corneal epithelial healing. PATIENTS AND METHOD 39 keratoconus patients following CXL and 11 patients following PRK were enrolled in this study. 21, 45 and 69 hours after CXL and 16, 37 and 61 hours following PRK slitlamp photographs were taken using fluorescein staining and the size of the epithelial defect and the time of epithelial closure was determined. As the observation time-points differed in both groups, the size of the epithelial defect following PRK was calculated for the time points used for analysis of CXL patients. These data were compared using chi-quadrat test. RESULTS Following crosslinking, epithelial closure occured within 3, following PRK within 4 days. In the area of epithelial erosion 45 and 69 hours after CXL or PRK treatment statistically significant difference (p = 0.005 and p<0.001) was verified. CONCLUSION Our results show beneficial effect of crosslinking on corneal epithelial healing. Orv. Hetil., 2017, 158(10), 376-379.Absztrakt: Bevezetes es celkitűzes: A crosslinking kezeles szaruhartya-hamosodasra gyakorolt hatasanak vizsgalata. Betegek es modszer: Vizsgalatunkba 39 keratoconusos beteget vontunk be crosslinking kezeles utan, es 11 pacienst fotorefraktiv keratectomiat kovetően (kontroll) crosslinking kezelest kovetően 21, 45 es 69 oraval. A festődő szaruhartyaham-hiany teruletet a fotorefraktiv keratectomiat kovetően 16, 37 es 61 oraval meghataroztuk. A fotorefraktiv keratectomia kezelesek utani kontrollok időpontja nem egyezett a crosslinking kezelest kovető kontrollidőpontokkal, igy a fotorefraktiv keratectomias csoportnal a hamhiany feltehető meretet a crosslinking kezelesi csoport meresi időpontjaira szamitottuk, es χ2-teszt segitsegevel hasonlitottuk ossze a ket csoportban a hamhiany meretet. Eredmenyek: A cornea crosslinking kezelest kovetően a szaruhartya hamjanak zarodasa a kezelestől szamitott harom napon belul, fotorefraktiv keratectomiat kovetően negy napon belul kovetkezett be. 45 es 69 ora elteltevel a ke...

Szemfelszíni laphám-neoplasia

Absztrakt: Jelen osszefoglaloban a szemfelszini lapham-neoplasiarol valo ismereteket osszegzik a szerzők, beleertve ezen daganattipus epidemiologiajat, etiologiajat, patologiajat, klinikai megjeleneset es kezeleset. A conjunctivalis intraepithelialis neoplasiaval es az invaziv laphamrakkal kapcsolatos kozlemenyeket tekintettek at a szerzők nehany sajat eset bemutatasaval, amelyek alapjan olyan alapvető irast szeretnenek kozolni, amely reszletesen taglalja es bemutatja jelenlegi ismereteinket a szemfelszini lapham-neoplasiarol. A szemfelszini lapham-neoplasia a leggyakoribb szemfelszini malignus tumor, illetve a choroidealis melanoma malignumot es a lymphomat kovetően a harmadik leggyakoribb okularis malignoma. Alacsony malignitasi potencialja ellenere előrehaladott stadiumban jelentős latasromlashoz vezethet, sőt akar a szemgolyo eltavolitasanak szuksegessege mellett tavoli metasztazis kialakulasakor az eletet is veszelyeztetheti. Gyakori recidivakepződes miatt kezeleseben elengedhetetlen az intra- es pos...To summarize actual knowledge on epidemiology, etiology, pathology, clinical apparence and treatment of ocular surface squamous neoplasias. We summarize up-to-date literature on conjunctival intraepithelial neoplasia and invasive squamous cell carcinoma and present some own cases. Ocular surface squamous neoplasia is the most common malignant ocular surface tumor and the third most common ocular malignancy following malignant melanoma and lymphoma. In spite of its low malignant potential, in advanced stages it may reduce visual acuity significantly or even the eye globe has to be removed. In case of metastasis it may also be life-threatening. As local recurrences of ocular surface squamous neoplasias may occur, knowledge of intra- and postoperative adjuvant treatment options are indispensable and regular control examinations are necessary. Identification and adequate treatment of ocular surface squamous neoplasias are necessary in order to avoid its progression and to prevent recurrences. Orv Hetil. 2017; 158(51): 2011-2022.