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Sirel Gür Güngör - One of the best experts on this subject based on the ideXlab platform.
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Comparison of the mechanical properties of the Anterior Lens Capsule in senile cataract, senile cataract with trypan blue application, and pseudoexfoliation syndrome.
Journal of cataract and refractive surgery, 2017Co-Authors: Cem Simsek, Sibel Oto, Gürsel Yilmaz, Dilek Dursun Altinors, Ahmet Akman, Sirel Gür GüngörAbstract:Purpose To evaluate the elastic modulus, hardness, and mechanical properties of the Anterior Lens Capsule in different types of cataract and to assess the correlation with age. Setting Baskent University Hospital, Department of Ophthalmology, Ankara, Turkey. Design Prospective comparative study. Methods Patients were divided into 3 groups. Group 1 comprised patients with senile cataract, Group 2 patients had pseudoexfoliation (PXF) syndrome, and Group 3 patients had dye-enhanced cataract surgery. The Capsules were analyzed using a nanoindentation device. Young's modulus of elasticity was measured by the Oliver-Pharr method and Capsule hardness by the Martens method. Results The study comprised 72 patients, 24 per group. The mean Young's modulus was 7.53 GPa ± 1.07 (SD) in Group 1, 6.01 ± 1.25 GPa in Group 2, and 8.12 ± 0.98 GPa in Group 3. The Capsules in Group 2 were more elastic than in Group 1 and Group 3 (P Conclusions Capsule thickness was positively correlated with increasing age in all groups. The Anterior Lens Capsules of patients with PXF had more elasticity and less stiffness than the other groups. Intracameral trypan blue application had no effect on Capsule elasticity and stiffness.
T Juhas - One of the best experts on this subject based on the ideXlab platform.
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Electron microscopic study of Anterior Lens Capsule allotransplants in chronic corneal ulcers.
Cornea, 2004Co-Authors: Igor Kozak, A Trbolova, Martin Zibrín, Tatiana Komorová, Lev Kolodzyeiski, T JuhasAbstract:Purpose: This study provides ultrastructural morphology and quantitative analysis ofallotransplants of Anterior Lens Capsule in the treatment of recurrent corneal ulcers. Methods: Mechanical ulcers of uniform size were created with a 6-mm corneal trephine in 9 eyes at one-third corneal depth in 6 white New Zealand male rabbits. Following initial epithelial regrowth, an identical injury was created in the same area of each cornea a second time. In 6 eyes (treated group), an Anterior Lens Capsule from a healthy donor rabbit was sutured into the ulcer bed, followed by antibiotic/steroid drops 3 times daily for 1 week. The remaining 3 control eyes were allowed to heal without surgical intervention using the same antibiotic/steroid drops only. Slit-lamp examination, histopathology, and electron microscopic findings with hemidesmosome counts and size were recorded over a 3-month follow-up period. Results: The control injured group had discontinuous epithelial basement membrane with significant reduction in hemidesmosome count compared with noninjured controls (P < 0.0001). The treated subgroup 7 days after surgery showed linear basement membrane with identifiable lamina lucida and densa and newly-formed hemidesmosomes, which were significantly more numerous than in the injured but nontreated group (P
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Immunofluorescent analysis of Anterior Lens Capsule allotransplantation for chronic corneal ulcers
Ceska a slovenska oftalmologie : casopis Ceske oftalmologicke spolecnosti a Slovenske oftalmologicke spolecnosti, 2004Co-Authors: Igor Kozak, A Trbolova, T Juhas, Rosocha J, Jautová J, LedeckýAbstract:This study uses immunofluorescent analysis to find out in histologic corneal sections a possible rejection reaction in Anterior Lens Capsule allotransplantation for chronic corneal ulcers. The experiment included control group of rabbit corneas with repeat injury to epithelium and Anterior stroma as well as surgically treated group. Fluorescein-conjugated human antibodies to IgA, IgM, IgG, complement and fibrinogen were used in the study. For detection we used method of direct immunofluorescence. Positive was only examination on fibrinogen in sections of treated group eyes 2 days after surgery. Last examination after 3 months failed to detect positivity in any of the tested markers. We preliminarily conclude that Anterior Lens Capsule allotransplantation for chronic corneal ulcers does not result in rejection reaction and that components of humoral immunity do not participate in immune reaction.
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experimental Anterior Lens Capsule transplantation for chronic corneal ulcers bowman s layer replacement
Cornea, 2003Co-Authors: Igor Kozak, A Trbolova, L Kolodzieyski, T JuhasAbstract:Purpose. This study was designed to measure the value of allografted Anterior Lens Capsule in the reepithelialization of recurrent corneal ulcers. Methods. Mechanical ulcers of uniform size were created with a 6-mm corneal trephine in both eyes of four Chinchilla male rabbits at one-third corneal depth. Following initial epithelial regrowth, an identical injury was created in the same area of each cornea a second time. In four eyes (treated group), an Anterior Lens Capsule from a healthy donor rabbit was sutured into the ulcer bed followed by antibiotic/steroid drops three times daily for 1 week. The remaining four control eyes were allowed to heal without surgical intervention using the same antibiotic/steroid drops only. Slit-lamp examination and histopathology findings were recorded over a 6-month follow-up period. Results. The four treated eyes reepithelialized after the second injury at a faster rate than the control group eyes and had a lower percentage of corneal opacification at all follow-up exam dates. Histopathology revealed normal epithelium overlying the transplanted Anterior Lens Capsule and no infiltration of inflammatory cells in the subepithelial stroma. Conclusions. In experimental conditions, allotransplantation of Anterior Lens Capsule speeds up reepithelialization after repeated mechanical trauma to the cornea. To our knowledge, this is the first experimental transplantation of an Anterior Lens Capsule to create an artificial Bowman's layer in recurrent corneal ulcerations to aid reepithelialization and minimize corneal scarring.
Olga Montoya - One of the best experts on this subject based on the ideXlab platform.
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non infectious endophthalmitis associated with trypan blue use in cataract surgery
International Ophthalmology, 2008Co-Authors: Roberto Velasquez, Olga MontoyaAbstract:Background The visualization of the Anterior Lens Capsule is greatly enhanced by trypan blue staining facilitating the creation of a continuous curvilinear capsulorhexis. Trypan blue has been deemed safe in this setting.
Marko Hawlina - One of the best experts on this subject based on the ideXlab platform.
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Ultrastructure of the Anterior Lens Capsule and epithelium in cataracts associated with uveitis.
Ophthalmic research, 2012Co-Authors: Spela Stunf, A Hvala, Nataša Vidovič Valentinčič, Aleksandra Kraut, Marko HawlinaAbstract:Aims: To study the ultrastructure of the Anterior Lens Capsule and epithelium, and capsular thickness in uveitic cataracts. Methods: Capsulorhexis samples from 20 uveitic cataracts were compared to 20 nuclear cataracts using the semi- and ultra-thin techniques. Results: Extensive epithelial and capsular-epithelial border changes and epithelial-mesenchymal transition in some fibrotic Capsules were found only in the uveitic group. All these changes were observed predominately in white uveitic cataracts. Mild and moderate ultrastructural changes were seen in both groups. Surface deposition of amorphous material was also found only in uveitic cataracts. Capsular thickness was not different between the two groups. Conclusions: Uveitic Capsules showed more extensive and different ultrastructural changes that probably occurred because of inflammation in the eye and epithelial-mesenchymal transition. These changes might be an additional reason for altered behavior of the Lens Capsule at capsulorhexis.
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Ultrastructure of Anterior Lens Capsule of intumescent white cataract
Acta ophthalmologica, 2011Co-Authors: Marko Hawlina, Spela Stunf, A HvalaAbstract:. Purpose: To analyse the Anterior Lens Capsule thickness and ultrastructure changes of intumescent white cataracts in comparison with nuclear cataracts to prove possible structural reasons for surgical difficulties with the intumescent white cataract. Methods: Anterior Lens Capsules from 35 eyes with intumescent white and 35 eyes with nuclear cataracts were analysed for their thickness by semithin sections technique and for morphological characteristics by transmission electron microscopy. Results: Capsule thickness was not significantly different in intumescent white compared to nuclear cataracts (mean values 17.5 and 18.5 μm, respectively, p = 0.369). The main morphological features of Capsules were extrusions of Capsule at the basement membrane-epithelial border embedding cellular material which were significantly more frequent in intumescent cataracts. Filaments in the basement membrane as well as rarefication of its structure and lamellae were often concomitant with the extrusions. Conclusions: Anterior Capsules of white intumescent cataracts do not differ in thickness but have different ultrastructure morphology compared to nuclear cataracts. The extrusions of basement membrane at the basement membrane-epithelial border towards epithelium, the filamentary inclusions within basement membrane and its rarefication could be the structural causes of tensile weakness and hence additional reason to surgical problems.
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human Anterior Lens Capsule epithelial cells contraction
Acta Ophthalmologica, 2009Co-Authors: Sofija Andjelic, Gregor Zupancic, Darko Perovsek, Marko HawlinaAbstract:. Purpose: Human Anterior Lens epithelial cells, attached to surgically isolated Capsules, were found to contract upon stimulation. The purpose of this study was to characterize these contractions, which create gaps between cells, and to assess the underlying physiological mechanisms and their possible association with cataract formation. Methods: Lens Capsules obtained during cataract surgery were stained with fluorescent dye Fura-2. Its fluorescence, upon excitation at 360 and 380 nm, was imaged to monitor changes in cell morphology and cytosolic free Ca2+concentrations ([Ca2+]i) in response to pharmacological stimulation by acetylcholine (ACh) and to mechanical stimulation by flow of saline or direct contact. Results: Epithelial cells contracted in approximately a third of preparations when stimulated by either ACh application, fluid movement or direct mechanical contact. Contractions started either before or at best simultaneously with the rise in [Ca2+]i. Contractions also occurred when there was hardly any change in [Ca2+]i upon application of physiological saline alone. The probability of contractions occurring did not differ significantly among cortical, nuclear and combined cortical + nuclear cataract. Conclusions: This study provides the evidence that contractions of the Anterior Lens epithelial cells take place in significant portion of human Lens Anterior Capsule postoperative preparations after non-specific stimulation. Contractions are at least partially independent of changes in [Ca2+]i. They can be mechanically induced, are localized and reversible and have a fast response and did not differ among different types of cataract. Physiological and clinical significance of this phenomenon remains to be elucidated.
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Ultrastructure of Anterior Lens Capsule in uveitic cataract
Acta Ophthalmologica, 2009Co-Authors: S Stunf, A Hvala, Nataša Vidovič Valentinčič, Aleksandra Kraut, Marko HawlinaAbstract:Purpose To evaluate the ultrastructure changes of Anterior Lens Capsule in patients with different forms of uveitis, who underwent cataract surgery at the University Eye Clinic Ljubljana, Slovenia between years 2001 and 2007. Methods Anterior Lens Capsules were obtained during cataract surgery, fixated and prepared for semi-thin sections technique and transmission electron microscopy. Results 22 uveitic cataract were studied (idiopathic Anterior uveitis-9, Fuchs-5, panuveitis-5, HSV-1, toxoplasmosis-1, uveitis in RA-1). The cataract was mature-1, cortical-14, fibrotic-1 or nuclear-6. The Anterior Capsule thickness showed irregularity in and between the cases spanning from 8,8 to 25,2 μm (average 16,33, SD 4,85μm). In 12 samples intrusions of Capsule at the Capsule-epithelial border embedding cellular material were found. Capsule itself showed ultrastructure changes in 18 samples, including: filaments, rarefication of Capsule or its Anterior chamber boarder, and lamellae. In 5 samples the amorphous material at the Anterior chamber boarder was seen. Epithelial changes were observed in all 22 samples, including: vacuolisation, multilayered epithelium, detached epithelium, intercellular space, star-shaped nuclei, necrotic cells, lipofucsin granules. In 4 samples the epithelium was unrecognizable due to extensive fibrosis or necrosis. Conclusion All studied uveitic cataracts showed epithelial and most also capsular changes. Some Capsules showed extensive changes with unrecognizable structures. The findings did not correlate to clinical appearance or diagnosis and most probably resulted from nonspecific response to inflammation. Amorphous depositions could be inflammatory debris. Further studies need to be done to explain the underlying processes.
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Application of agar sandwich technique for morphologic studies of Anterior Lens Capsule
Acta Ophthalmologica, 2008Co-Authors: S Stunf, A Hvala, M Globocnik Petrovic, Marko HawlinaAbstract:Purpose Preparation of the Anterior Lens Capsule for morphological studies is difficult due to its transparency, small size and delicacy. During preparation the Capsule curls upon itself, causing various artefacts in Capsule thickness and epithelial cells organization. The samples can also be easily lost. To overcome these problems, the agar sandwich technique was introduced. Methods The Capsules were obtained during routine cataract surgery and immediately fixated in 10% paraformaldehid for 1 to 2 hours. The agar sandwich consisted of 8mm wide agar disc and agar in liquid state, to be poured over the disc. The discs were pre-prepared and stored in alcohol, while the liquid phase was stored cold in syringe and melted for each case. With the aid of laboratory microscope pre-fixated Capsule was gently straightened on the agar disc, mounted in the agar sandwich and fixated overnight. Fixation was followed by standard procedure for light or electron microscopy samples. Results Anterior Lens Capsules from different cataracts were included in the study. Once positioned in the sandwich, the Capsule remained in its shape throughout the preparation. The agar sandwich did not interfere with the standard Hematoxilyn-Eosin staining or cutting. Agar was clearly seen around the Capsule on light microscopy samples. The appearance of basement membrane remained unchanged. However, for epithelial cells preservation the pre-fixation and gentle handling of the sample were crucial. Conclusion The agar sandwich technique is a not-complicated technique, which turned out as an effective method in processing of the Anterior Lens Capsule samples. In combination with pre-fixation no interfering with histological section or interpretation was noted.
Alistair Laidlaw - One of the best experts on this subject based on the ideXlab platform.
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Choroidal effusions and hypotony caused by severe Anterior Lens Capsule contraction after cataract surgery.
American journal of ophthalmology, 2000Co-Authors: Joel Salzmann, Peng T. Khaw, Alistair LaidlawAbstract:Abstract PURPOSE: To report the clinical features and management of two patients with pseudophakic Anterior Capsule contraction with secondary tractional ciliary body detachments and hypotonous choroidal effusions. METHODS: Case reports. RESULTS: In two eyes of two patients with pseudophakia, severe Anterior Lens Capsule contraction and tractional ciliary body detachments, Anterior capsulotomy (one Nd:YAG laser, one surgical), was followed by resolution of the ocular hypotony and resolution/nonrecurrence of the choroidal effusions. In both cases, continuous curvilinear capsulorhexis was used during cataract surgery. CONCLUSION: Anterior Capsule contraction following pseudophakia may result in tractional ciliary detachment and secondary ocular hypotony. Radial Anterior capsulotomy appeared to be effective in both cases.