Morphological changes in the edge structures following femtosecond laser capsulotomy with varied patient interfaces and different energy settings.

BACKGROUND: To ascertain the morphological changes in the edge structure of femtosecond laser-derived capsulotomy specimens using varying patient interfaces and different laser pulse energies. METHODS: In this experimental clinical study femtosecond laser-assisted capsulotomies were performed in 30 eyes using the LenSx femtosecond laser (LenSx, Alcon, Fort Worth, TX, USA). Surgery was performed using either a rigid curved contact interface (group 1, 15 eyes) or a curved interface with a soft contact lens between cornea and interface (group 2, 15 eyes). The laser pulse-energy was set to 15 µJ in group 1 and to 5 µJ in group 2. After the removal of the anterior capsule, half of the specimens from each group underwent either further staining for light microscopy (LM) or scanning electron microscopy (SEM). Cell configuration, capsule shape, and edge abnormalities were analysed on a morphological basis. RESULTS: LM showed continuous anterior capsular incisions with a prominent demarcation line along the cutting edge, as well as tags and bridges, which were more pronounced in group 1. SEM revealed further smaller microgrooves and sawtooth patterns in both groups, and a more regular demarcation line configuration in group 2. CONCLUSION: A soft contact lens interface with a subsequent laser pulse energy of 5 µJ resulted in fewer tags and bridges, smoother edges, and a more regular and thinner demarcation line on specimens edges of femtosecond laser-performed capsulotomies compared to a rigid curved 15 µJ interface application.

Cell death and ultrastructural morphology of femtosecond laser-assisted anterior capsulotomy.

PURPOSE: To evaluate cell death and ultrastructural effects on capsulotomy specimens derived from femtosecond laser-assisted cataract surgery. METHODS: In 26 eyes, an anterior capsulotomy was performed using a femtosecond laser. In 10 eyes (group 1), the laser-pulse energy was set to 15 µJ using a rigid curved interface and in another 10 eyes (group 2) to 5 µJ using a curved interface combined with a soft contact lens. The control group (6 eyes, group 3) underwent manual anterior capsulorhexis using forceps. All extracted capsule specimens underwent cell death analysis using the TUNEL kit, ultrastructural analyses using atomic force microscopy (AFM), and scanning electron microscopy (SEM). Counterstaining was performed with 4',6-diamidino-2-phenylindol (DAPI) and hematoxylin-eosin (HE). RESULTS: Cell death was found in all capsule specimens along the cutting edge but was significantly more pronounced in group 1. DAPI and HE staining showed regular epithelial cell distribution with a demarcation line along the cutting edge of both laser groups, which was more pronounced in group 1. In AFM analysis, laser spot size in the femtosecond laser groups were in accordance with the preoperative planned size (P < 0.01). Cutting edges in SEM observations were smoother and more roundly shaped using 5 µJ (group 2). CONCLUSIONS: Cutting edges of femtosecond laser-performed capsulotomies are precise and laser spot lesions are within planned size. Cell death reaction depends on the laser pulse energy settings and can be reduced to the level observed in a manual capsulorhexis.

Light microscopy and scanning electron microscopy analysis of rigid curved interface femtosecond laser-assisted and manual anterior capsulotomy.

PURPOSE: To study the microanatomic edge structures of anterior lens capsule specimens derived from manual and femtosecond laser-assisted capsulotomies. SETTING: Department of Ophthalmology, Goethe-University, Frankfurt, Germany. DESIGN: Experimental study. METHODS: Of 60 eyes with lens removal and intraocular lens implantation, 30 received a manual capsulotomy and 30 received a femtosecond laser-assisted capsulotomy (Lensx, rigid curved interface, pulse energy 15 µJ, spot separation 4 µm, layer separation 3 µm). After anterior capsule removal, tissues were immediately fixed in 4.5% formalin. Approximately 30 minutes after fixation, the tissues were removed from the fixation containers and air dried for at least 2 hours. Fifteen capsules in each group had further staining for light microscopy (LM). The surface of the capsulotomy edge was the primary focus of LM and scanning electron microscopy (SEM). Cell configuration, capsule shape, and abnormalities were evaluated. RESULTS: Subjective LM and SEM analysis showed smooth edges at all magnifications, no cell destruction, and cells up to the cutting edge in the manual capsulotomy group. Light microscopy demonstrated almost continuous anterior capsule incisions of the femtosecond laser-assisted capsulotomy, a prominent demarcation line along the cutting edge, and several tags and bridges. Scanning electron microscopy showed microgrooves and valley- and mountain-like structures as signs of the photodisruption process. CONCLUSION: Compared with manual procedures, curved, rigid interface femtosecond laser-assisted capsulotomy specimens using 15 µJ pulse energy showed tags, bridges, rougher edges, and demarcation lines on the capsulotomy edges on SEM but subjectively estimated a more round shape on LM. FINANCIAL DISCLOSURES: Mr. Klaproth received travel reimbursements and/or lecture fees from Alcon Laboratories, Inc., Rayner Intraocular Lenses Ltd., and Oculus GmbH. Dr. Kohnen received travel reimbursements, grant support, and/or lecture fees from Alcon Laboratories, Inc., Abbott Medical Optics, Inc., Bausch & Lomb, Carl Zeiss Meditec AG, Neoptics AG, Rayner Intraocular Lenses Ltd., and Schwind eye-tech-solutions GmbH and Co. KG; he is a consultant to Alcon Laboratories, Inc., Carl Zeiss Meditec AG, Rayner Intraocular Lenses Ltd., and Schwind eye-tech-solutions GmbH and Co. KG. No other author has a financial or proprietary interest in any material or method mentioned.

Corneal decompensation and angle-closure glaucoma after upside-down implantation of an angle-supported anterior chamber phakic intraocular lens.

We present the case of a 27-year-old man with severe pain, loss of visual acuity, corneal edema, and high intraocular pressure (IOP) in 1 eye after bilateral Acrysof Cachet phakic intraocular lens (pIOL) implantation. Slitlamp examination was limited due to severe corneal edema, but anterior segment optical coherence tomography indicated upside-down implantation of the pIOL. The pIOL was explanted, which confirmed that the haptic indicator had been implanted counterclockwise. Postoperative treatment included antiinflammatory and antiglaucoma topical therapy. Follow-up monitoring showed decreasing corneal edema and normalized IOP. At 6 weeks, the corrected distance visual acuity was +0.1 logMAR, the IOP was within normal limits, and the cornea showed no signs of edema, but there was endothelial cell density loss. This case presents the preoperative and postoperative management of high IOP after pIOL implantation and illustrates the pitfalls of incorrect implantation of angle-supported anterior chamber IOLs with haptic angulation.