Safety and Precision of Two Different Flap-morphologies Created During Low Energy Femtosecond Laser-assisted LASIK

Purpose: Currently, two major principles exist to create LASIK flaps: firstly, a strictly horizontal (2D) cut similar to the microkeratome-cut and secondly an angled cut with a “step-like” edge (3D). The strictly horizontal (2D) cut method can be performed using apparatus such as the low-energy FEMTO LDV Z8 laser and its predecessors which are specific to this type. Alternatively, the low-energy FEMTO LDV Z8 laser’s 3D flap design creates an interlocking flap-interface surface which potentially contributes toward flap stability. In addition, the FEMTO LDV Z8 offers flap-position adjustments after docking (before flap-creation). The current study analyzed precision, safety, efficacy, as well as patient self-reported pain and comfort levels after applying two different types of LASIK flap morphologies which were created with a low-energy, high-frequency femtosecond (fs) laser device. Methods: A prospective, interventional, randomized, contralateral eye, single-center comparison study was conducted from November 2019 to March 2020 at the Hamburg vision clinic/ zentrumsehstärke, Hamburg, Germany. Eleven patients and 22 eyes received low-energy fs LASIK treatment for myopia or myopic astigmatism in both eyes. Before the treatment, the eyes were randomized (one eye was treated with the 2D, the other eye with the 3D method). Results: The mean central flap thickness one month after surgery was 110.7 ± 1.6 μm (2D) and 111.2 ± 1.7 μm (3D); P = 0.365 (2D vs 3D). Flap thickness measured at 13 different points resulted in no statistically significant differences between any of the measurement points within/between both groups; demonstrating good planarity of the flap was achieved using both methods. Despite not being statistically significant, the surgeons recognized an increase in the presence of an opaque bubble layer in the 3D flap eyes during surgery and some patients reported higher, yet not statistically significant, pain scores in the 3D flap eyes during the first hours after the treatment. Overall, safety- and efficacy indices were 1.03 and 1.03, respectively. Conclusion: In this prospective, randomized, contralateral eye study, the low-energy fs laser yielded predictable lamellar flap thicknesses and geometry at one-month followup. Based on these results, efficacy and safety of the corresponding laser application, that is, 2D vs 3D, are equivalen

Entwicklung der Ehe- und Sexualberatung der Deutschen Demokratischen Republik aus historischer Sicht

HUB(11) - 81 HB 5207 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Pikosekundenlaser-Faser-assistierte Sklerostomie (PIRL-FAST): Ein erster Machbarkeitsnachweis

Einleitung Ziel der vorliegenden Studie war die Analyse der Machbarkeit einer PIRL- Faser-assistierten Sklerostomie mit einer neuartigen Saphirfaser bei unterschiedlichen Pulsenergien des Pikosekundenlasers. Methodik Die laserassistierten Sklerostomien wurden mit einer neu generierten Saphirfaser des PIRL-HP2-1064 OPA-3000 (Attodyne Inc., Kanada) gefertigt. Direkt im Anschluss an die Intervention wurden die Augen in Phosphat-gepuffertem Formaldehyd fixiert (3,5 %) und im Rahmen der histologischen Aufarbeitung für die nachfolgenden Untersuchungen in 4 μm dicke Schnitte zugeschnitten und mittels Hämatoxylin-Eosin (H. E., Merck, Darmstadt, Deutschland) gefärbt. Alle angefertigten Präparate wurden eingescannt und digitalisiert mit dem MIRAX SCAN (Carl Zeiss Microimaging GmbH, Jena, Deutschland). Ergebnisse Gewählt wurden die Pulsenergien von 150 μJ (N = 4), 175 μJ (N = 6), 200 μJ (N = 7) und 250 μJ (N = 6). Ausgewertet wurden im Rahmen dieser ersten Machbarkeitsanalyse 400 μm (10 aufeinanderfolgende Schnitte) der geschaffenen Sklerostomie. Es zeigte sich hinsichtlich der geschaffenen Fläche der Sklerostomie ein signifikanter Unterschied der Gruppe, welche mit 250 μJ gelasert wurde im Vergleich zu allen anderen Gruppen. Es zeigte sich, dass diejenigen Sklerostomien, welche mit 250 μJ gelasert wurden, signifikant mehr Kollateralschadenszone im Vergleich zum geschaffenen Durchmesser aufwiesen als die anderen 3 Gruppen. Zusammenfassung PIRL-FAST mittels Saphirfaser ist ein neues, minimalinvasives Instrument zur Schaffung einer stabilen Verbindung zwischen der Vorderkammer und dem Subkonjunktivalraum. Da der PIRL sich bereits als ein effizientes Instrument zum Schneiden verschiedenster Gewebe bewiesen hat, verbunden mit einem geringen Kollateralschaden, könnten diese ersten Machbarkeitsstudien einen neuen Weg in Richtung minimalinvasiver Glaukomchirurgie ebnen. Weitere Analysen zur Wundheilung und Narbenbildung in vivo wurden bereits eingeleitet.Introduction The aim of this study was an analysis of the feasibility of a picosecond infrared laser fiber-assisted sclerostomy (PIRL-FAST) using a novel sapphire fiber and different energy levels of the picosecond laser. Method The laser-assisted sclerostomy was carried out with a newly generated sapphire fiber of the PIRL-HP2-1064 OPA-3000 (Attodyne, Canada). Immediately after the intervention, the eyes were fixed in phosphate-buffered 3.5% formaldehyde. For subsequent histological analysis the eyes were cut into 4 μm thick sections and stained with hematoxylin and eosin (H&E, Merck, Darmstadt, Germany). All preparations were then scanned and digitalized using the MIRAX SCAN (Carl Zeiss Microimaging GmbH, Jena, Germany). Results The pulse energies 150 μJ (N = 4), 175 μJ (N = 6), 200 μJ (N = 7) and 250 μJ (N = 6) were selected. Within the framework of this first feasibility analysis 400 μm (10 sequential sections) of the sclerotomies were evaluated. The mean area of PIRL-FAST showed a dependency on the pulse energy applied. The diameter of the collateral damage zone (CDZ) depended on the pulse energy used. The largest CDZ could be measured using the highest pulse energy in this experiment (250 μJ). The environmental scanning electron microscope (ESEM) results revealed circular smooth sclerostomy wall with only minimal change of tissue ultrastructure. Conclusion The PIRL-FAST using sapphire fibers is a new minimally invasive instrument to provide robust stenting from the anterior chamber to the subconjunctival space. Since the PIRL has proven to work efficiently in sectioning several tissues with minimal collateral damage these first proof of principle experiments might pave the way for a new minimally invasive glaucoma surgery strategy. We have already initiated experiments to analyze the wound healing and scar formation in vivo