Capsulotomy Specimens Research Articles

Scanning Electron Microscopy Analysis of the Anterior Capsulotomy Edge: A Comparative Study between Femtosecond Laser-Assisted Capsulotomy and Manual Capsulorhexis.

Purpose To compare the capsule edges ultrastructure obtained by two femtosecond laser-assisted cataract surgery (FLACS) platforms and manual continuous curvilinear capsulorhexis (CCC) using scanning electron microscopy (SEM). Setting Eye Clinic, University of Trieste, Italy. Design Experimental comparative study. Methods 150 anterior capsules were collected and divided into three groups as follows: Group 1 (50 capsules) obtained with manual CCC, Groups 2 and 3 (each with 50 capsules) obtained with the Catalys Laser and the LenSx Laser, respectively. All samples were imaged by means of SEM and regularity of the cut surface, and thickness of the capsule edge were evaluated and compared. Results All femtosecond laser (FSL) capsules were perfectly circular, whereas some alteration of the circular shape was observed in the manual ones. Group 1 showed a smooth and regular capsule edge without any surface irregularity, conversely Groups 2 and 3 showed postage-stamp perforations on the capsule edge. The cut surface irregularity value in Group 2 was 1.4 ± 0.63, while it was 0.7 ± 0.49 in Group 3 (p < 0.05). Group 1 had a significantly lower thickness of the capsule edge than the FSL groups (p < 0.05). No statistically significant difference in the capsule edge thickness between the FSL groups was found (p=0.244). Conclusions Despite the presence of slight cut surface irregularities, both FSL capsulotomies showed a better geometry and circularity than the manual ones. Capsulotomy specimens obtained using both FSL capsulotomies showed laser-induced alterations of the capsule edge when compared with smooth and regular edges obtained using manual CCC.

Intraoperative performance and ultrastructural integrity of human capsulotomies created by the improved precision pulse capsulotomy device

To investigate the intraoperative performance and the ultrastructural features of anterior capsulotomy performed with the improved Zepto precision pulse capsulotomy (PPC) device. Launceston Eye Institute, Launceston, Tasmania, Australia. Prospective, consecutive case series. Intraoperative observation of performance and complications were made on consecutive eyes having capsulotomies with the improved PPC device. The capsulotomy specimens were examined under scanning electron microscope and compared with manual continuous curvilinear capsulorhexis and femtosecond laser-assisted cataract surgery specimens. The study comprised 52 eyes. Intended capsulotomy occurred in 50 eyes with 2 device failures. Complete free-floating capsulotomies were achieved in 48 eyes (96%). Anterior capsule tears occurred in 2 eyes (4%). The ability of the PPC device to create complete free-floating capsulotomies improved; however, the radial tear rate remained high. The ultrastructural features in exvivo human capsulotomy specimens still showed areas of irregular capsule margin with frayed edges.

Ultrastructural Integrity of Human Capsulotomies Created by a Thermal Device

To investigate the ultrastructural features of anterior capsulotomy performed with a thermal device, the precision pulse capsulotomy (PPC). Prospective, multicenter case series. Consecutive patients undergoing capsulotomy with the PPC device. Prospective study of patients undergoing capsulotomy with the PPC by 2 surgeons, followed up by routine phacoemulsification cataract surgery, was undertaken. All capsulotomy specimens were collected for scanning electron microscopy (SEM). Observations were made regarding uniformity of the capsular edge and the presence of irregularities that may compromise integrity. Comparisons were made with manual continuous curvilinear capsulorrhexis. Ultrastructural features of PPC and presence of irregularities. Frayed appearance of the anterior capsule edge was noted in postoperative visits under slit-lamp examination. Scanning electron microscopy sampling showed a generally uniform rolled capsular edge, but interspersed with areas of irregularity with frayed appearance at the capsule margin. The PPC device is capable of creating reproducible, central, and precise circular capsulotomy. The ultrastructural features in exvivo human capsulotomy specimens generally show eversion of the capsulotomy edge, but in some cases, this was accompanied by areas of irregular capsule margin with frayed edges, likely caused by dissipated thermal energy. The postoperative appearance and SEM features warrant further assessment of the PPC integrity and clinical correlation.

Apoptosis Factors of Lens Epithelial Cells Responsible for Cataractogenesis in Vitrectomized Eyes with Silicone Oil Tamponade

BackgroundThe aim of this study was to determine the expression of apoptotic factors Bax, Bcl-2, and Caspase-3 in lens epithelial cells (LECs) from cataracts secondary to pars plana vitrectomy with silicone oil (SO) tamponade. We also investigated the impact of SO emulsification on the expression of apoptotic factors.Material/MethodsAnterior capsulotomy specimens of 20 eyes in 20 patients with cataract secondary to SO tamponade (Group 2), were collected. Another 20 eyes of 20 patients with age-related cataract (Group 1) were recruited as controls. The anterior capsule specimens were obtained from the patients during cataract surgery, frozen and later analyzed with respect to immunohistochemical stains of Bax, Bcl-2, and Caspase-3 using a confocal microscope.ResultsAge, sex, and laterality did not show any difference between the 2 groups. There was a greater increase in Bax and Caspase-3 expression in LEC in Group 2 than in Group 1 (PBax<0.0001, PCaspase-3<0.0001). The Bcl-2 expression decreased in Group 2, although the difference was not significant (P=0.616). The changes of apoptosis factors are not associated to SO emulsification (PBax=0.354, PBcl-2=0.728, PCaspase-3=0.939).ConclusionsThe caspase-3-dependent apoptosis of LECs increased in complicated cataract patients with SO endotamponade. The Bax played a critical role in regulating apoptosis of LECs in vitrectomized eyes with SO tamponade. The SO emulsification had no significant impact on the expression of apoptosis factors.

Cell Death and Ultrastructural Morphology of Femtosecond Laser–Assisted Anterior Capsulotomy

To evaluate cell death and ultrastructural effects on capsulotomy specimens derived from femtosecond laser-assisted cataract surgery. 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). 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). 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.

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

To ascertain the morphological changes in the edge structure of femtosecond laser-derived capsulotomy specimens using varying patient interfaces and different laser pulse energies. 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 15μJ in group 1 and to 5μJ 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. 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. A soft contact lens interface with a subsequent laser pulse energy of 5μJ 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 15μJ interface application.

Anterior Capsulotomy Integrity after Femtosecond Laser-Assisted Cataract Surgery

To compare the incidence of anterior capsular tears after femtosecond laser-assisted cataract surgery (FLACS) versus phacoemulsification cataract surgery (PCS) and to assess the ultrastructural features of anterior capsulotomy specimens (FLACS and PCS) using electron microscopy. Prospective, multicenter, comparative cohort case series. Consecutive patients undergoing FLACS or PCS. A prospective cohort study of all patients (n= 1626) undergoing FLACS or PCS by 2 surgeons from centers A and B was undertaken to compare the incidence of anterior capsule tears. Anterior lens capsules were collected by 4 surgeons from centers A, B, C, and D using 3 different commercially available femtosecond platforms, each with latest version upgrades. Lens capsule tissue was prepared for scanning electron microscopy (SEM) using a total of 10 samples for patients undergoing PCS, and 40 samples for patients undergoing FLACS. Incidence of anterior capsule tear and comparative ultrastructural features of capsular samples from both PCS and FLACS cases. There was a significantly increased rate of anterior capsule tears in the FLACS group (15/804 [1.87%]) when compared with the PCS group (1/822 [0.12%]; P= 0.0002, Fisher exact test). In 7 cases, the anterior capsule tear extended to the posterior capsule. Because all cases had occurred in complete capsulotomy, the integrity of the anterior capsule was questioned in the FLACS group. Subsequent SEM sampling showed irregularity at the capsule margin, as well as multiple apparently misplaced laser pits in normal parts of the tissue. Aberrant pits were approximately 2 to 4 μm apart and occurred at a range of 10 to 100 μm radially from the capsule edge. Laser anterior capsulotomy integrity seems to be compromised by postage-stamp perforations and additional aberrant pulses, possibly because of fixational eye movements. This can lead to an increased rate of anterior capsule tears, and extra care should be taken during surgery after femtosecond laser pretreatment has been performed. A learning curve may account for some of the increased complication rate with FLACS. However, the SEM features raise safety concerns for capsular integrity after FLACS and warrant further investigation.

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

To study the microanatomic edge structures of anterior lens capsule specimens derived from manual and femtosecond laser-assisted capsulotomies. Department of Ophthalmology, Goethe-University, Frankfurt, Germany. Experimental study. 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. 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. 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. 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.

Expression of osteonectin in lens epithelium cells in age-related cataract

To study the expression of osteonectin (also called secreted protein acidic and rich in cysteine, SPARC) in the lens epithelium cells in cortex cataract and nucleus cataract. This is an experimental research. Forty-five capsulotomy specimens were obtained from 33 patients suffered form pure cortex or/and nucleus cataracts and classified as nucleus group and cortex group, between May to July of 2010. Immunohistochemistry was used to detect the SPARC, which was analyzed by gray value. TUNEL was used to examine the apoptosis of lens epithelium cell. The difference of SPARC expression and apoptosis rate between these two groups was analyzed by LSD-t. Twenty specimens were studied with immunohistochemistry (C/N = 8/12), and 25 specimens studied by TUNEL test (C/N = 9/16). Expression of SPARC in the cortex group was significantly less than that in the nucleus group (peripheral region: t = 2.827, P < 0.05; central region: t = 2.264, P < 0.05). Expression of SPARC in the central region was significantly less than that in the peripheral region (peripheral region: t = 3.473, P < 0.05; central region: t = 2.771, P < 0.05). Apoptosis rate in the nucleus group was significantly lower than the cortex group (nucleus group: t = 2.364, P < 0.05; cortex group: t = 2.723, P < 0.05). Apoptosis rate in peripheral region was significantly less than that in central region (nucleus group: t = 2.771, P < 0.05; cortex group: t = 2.473, P < 0.05). The expression of SPARC is different between nucleus cataract and cortex cataract and also different between central and peripheral regions. The expression of SPARC is related with apoptosis of lens capsule epithelium cells.

Contributions of Mouse Genetic Background and Age on Anterior Lens Capsule Thickness

Accurate lens capsule thickness measurements are necessary for studies investigating mechanical characteristics of the capsule. Confocal Z-axis imaging was used to measure the anterior lens capsule thickness of living intact lenses with minimal tissue manipulation. Measurements of the anterior capsule thickness is reported for the first time in young and old mice from four inbred strains, BALB/c, FVB/N, C57BL/6, and 129X1, and the outbred strain ICR. Our data demonstrates that the mouse anterior lens capsule continues to grow postnatally similar to that described in other mammals. It is also shown there is a significant difference in anterior lens capsule thickness between unrelated mouse strains, suggesting that capsule thickness is a quantitative trait shared by strains with common ancestry. Measurements, taken from other regions of FVB/N capsules revealed the anterior pole to be the thickest, followed by the equatorial region and posterior pole. In addition to mouse, anterior capsule measurements taken from intact cattle, rabbit, rat lenses, and human capsulotomy specimens correlated with the overall size of the animal.

Interaction with Collagen IV Protects Lens Epithelial Cells from Fas-Dependent Apoptosis by Stimulating the Production of Soluble Survival Factors

To investigate the sensitivity of lens epithelial cells (LECs) to Fas-dependent apoptosis and to determine the role of interaction with the extracellular matrix (ECM) in the regulation of Fas-dependent apoptosis. Sensitivity to Fas-mediated apoptosis of primary human LECs and HLE-B3 LECs cultured on different substrates was determined by Hoechst staining after incubation with Fas-stimulating or control IgM. Fas expression was determined by Western blot analysis. Effects of varied cell density and conditioned media from HLE-B3 cells cultured on different substrates on the Fas sensitivity of HLE-B3 cells cultured on tissue culture (TC) plastic were determined. Primary LECs cultured as free-floating anterior capsulotomy specimens were resistant to Fas-dependent apoptosis. The LE cell line, HLE-B3, was sensitive to Fas-dependent apoptosis when cultured on TC plastic but not on lens capsule. Culture on collagen IV, but not on laminin, rendered HLE-B3 cells resistant to Fas-dependent apoptosis, although Fas was still expressed. Primary LECs cultured on TC plastic after migration from lens capsule explants were resistant to Fas-dependent apoptosis if the lens capsule and attached cells were still present, but not if the lens capsule had been removed. Conditioned medium from LECs cultured on collagen IV, but not TC plastic, protected cells cultured on TC plastic from Fas-dependent apoptosis. The protective effect of culture on collagen IV diminished with decreasing cell density. LECs are protected from Fas-dependent apoptosis by interaction with collagen IV. Soluble factors released by the LECs cultured on collagen IV protect LECs from Fas-dependent apoptosis.

Lens Epithelial Apoptosis and Cell Proliferation in Human Age-Related Cortical Cataract

To probe the presence of apoptosis in the epithelium of human lenses with age-related cortical cataract as well as to assess cell proliferation, a predicted consequence of apoptotic cell death, in this specific cell population. DNA fragmentation was assessed using terminal digoxigenin-labeled dUTP nick end labeling (TUNEL) in capsulotomy specimens obtained from patients who underwent either extracapsular cataract extraction for the removal of adult-onset cortical cataract (n=27) or clear lens extraction for the correction of high myopia (n=25). Cell proliferation was assayed in 23 epithelia of cataractous lenses, and 20 epithelia of non-cataractous lenses with the proliferation marker MIB1, a monoclonal antibody against the nuclear antigen Ki-67 that is detected throughout the cell cycle but is absent in the resting (G0) cell. TUNEL staining was observed in 25 (92.6%) specimens of cataractous lenses, whereas cells undergoing apoptosis were identified in 2 (8%) of the epithelia from non-cataractous lenses. Only two MIB1-positive samples were detected, one of which was a capsule obtained during intracapsular cataract extraction. The epithelium of human lenses with cortical cataract undergoes low rate apoptotic death. This limited epithelial apoptosis is unlikely to result in any significant cell density decrease since epithelial gaps are likely to be replaced by cell proliferation at the germinative zone of the anterior lens capsule. Nevertheless, the accumulation of small-scale epithelial losses during lifetime may induce alterations in lens fiber formation and homeostasis and result in loss of lens transparency.

Water-mediated lysis of lens epithelial cells attached to lens capsule

Purpose: To investigate the effect of distilled deionized water (DDW) on lens epithelial cells (LECs) attached to the lens capsule. Setting: Wound Healing Research Laboratory, Center for Vision Research, Westmead Hospital, Sydney, NSW, Australia. Methods: Anterior capsulotomy specimens taken during routine cataract surgery were divided in half. One half was immersed in DDW and the other half in culture medium (control) for 1 to 5 minutes and photographed at intervals by phase-contrast microscopy. In further experiments, the capsules were exposed to DDW for 1 or 2 minutes and placed in culture for 1 week to determine whether LECs survive treatment and are capable of repopulating the lens capsule. Results: Distilled-deionized water induced marked swelling of the cytoplasm within 60 seconds of treatment. At 120 seconds, there was disruption of the plasma membranes, with few intact cells remaining. In the control capsules, confluent monolayers of LECs covered the entire capsule surface with a halo of LECs growing on the surrounding plastic well. Viable LECs were observed in 1 of 3 capsules treated for 1 minute with DDW. These did not reach confluence or grow off the capsule onto the surrounding well. No viable LECs were seen on capsules exposed to DDW for 2 minutes. Conclusions: Short exposure of LECs to DDW induced extensive and rapid cell lysis. Distilled-deonized water may be a useful agent for instillation in the capsular bag during sealed-capsule irrigation to prevent posterior capsule opacification.

Decreased caspase-3 activity in human lens epithelium from posterior subcapsular cataracts

Apoptosis has been implied in normal lens development in the embryo as well as in lens fibre differentiation. It has also been suggested to play a role in non-congenital cataract and in the formation of posterior subcapsular opacification, but data on the presence of apoptosis in human lens epithelium from cataractous lenses are scarce and conflicting. The present study aimed to investigate apoptosis in lens epithelium from patients undergoing cataract surgery. The amount of apoptosis detected was correlated to age, gender, type of cataract, medications and disease. Moreover, the ability of human lens epithelial cells in culture to respond to the apoptosis-inducing agent staurosporin by activation of caspase-3 was investigated. Human lens capsulotomy specimens were collected immediately after surgery, frozen and later analysed with respect to caspase-3 activity, using the fluorogenic substrate Ac-DEVD-AMC. Generally, the activity of caspase-3 detected in this manner was very low and in 23% of the specimens it was non-detectable. However, there were differences in caspase activity between lens epithelial cells from different types of cataract, where samples from lenses with posterior subcapsular cataract exhibited significantly lower caspase-3 activity than lenses with a clear subcapsular zone. Age, gender or medications did not show any correlation with caspase activity but human capsulotomy specimens from diabetic patients exhibited significantly lower caspase-3 activity. Staurosporin caused a concentration-dependent increase in caspase activity in cultured human lens epithelial cells and the amount of apoptotic nuclei was also increased as viewed by staining with Hoechst 33342, showing chromatin condensation and nuclear fragmentation. Similar results were obtained when fresh human lens capsulotomy specimens were exposed to 1000 n m staurosporin for 24 hr. To conclude, the present data indicate that human lens epithelial cells have the ability to respond to apoptosis-inducing agents with caspase-3 dependent apoptosis, and that even though the general level of apoptosis in human lens epithelium in vivo is low, there are differences in caspase-3 activity levels in lenses with or without posterior subcapsular cataract. The latter finding supports previous studies indicating that this type of cataract may result from defective differentiation, in which apoptosis may play an important role.

Immunohistochemical Study of Apoptosis of Lens Epithelial Cells in Human and Diabetic Rat Cataracts

Purpose: To evaluate apoptosis of lens epithelial cells by immunohistochemical methods. Methods: We performed terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assays on capsulotomy specimens (53 patients, 68 eyes) from patients who had undergone cataract surgery, and on the epithelium of diabetic cataracts in rats (72 rats, 144 eyes). An animal model of diabetic cataracts was prepared by injection of streptozotocin in 3-week-old rats. The specimens of rats were also examined using the proliferating cell nuclear antigen (PCNA) immunohistochemical staining method. Results: Although some TUNEL-positive cells were detected in capsulotomy specimens, we recognized little correlation between their distribution and the morphological classification of the cataracts. In the animal model of diabetic cataracts, TUNEL-positive cells were seen around the regions of accumulated epithelial cells. In the accumulated regions, PCNA-labeled cells undergoing DNA synthesis were also detected. Conclusions: These results suggest the possibility that apoptosis occurs in human lens epithelial cells. Apoptosis and proliferation of lens epithelial cells may be induced by factors such as hyperglycemia.

Immunohistochemical Study of Apoptosis of Lens Epithelial Cells in Human and Diabetic Rat Cataracts

Purpose: An immunohistochemical evalution of lens epithelial cell apoptosis. Methods: We performed terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assays on capsulotomy specimens (68 eyes in 53 patients) from patients who had undergone cataract surgery and an epithelium of diabetic cataracts in rats (144 eyes in 72 rats). The animal model of diabetic cataracts was prepared by injection of streptozotocin in three-week old rats. The rats were also examined using the proliferating cell nuclear antigen (PCNA) immunohistochemical staining method. Results: Although some TUNEL-positive cells were detected in capsulotomy specimens, we recognized little correlation between its distribution and morphological classification of cataracts. In the animal model of diabetic cataracts, TUNEL-positive cells were seen around the region where epithelial cells had accumulated. In the accumulated region, PCNA labeled cells undergoing DNA synthesis were also detected. Conclusion: These results suggest the possibility that apoptosis occurs in human lens epithelial cells and apoptosis and proliferation may be induced by factors such as hyperglycemia.

Precapsular layer of the anterior lens capsule in early pseudoexfoliation syndrome.

We examined a possible correlation between clinical signs of early pseudoexfoliation (PSX) syndrome related to pigment dispersion and iris stroma atrophy and morphological alterations of the lens capsule. 63 anterior lens capsules (30 PSX suspects, 3 pre-PSX, 10 PSX, 20 controls) were studied by transmission and immuno-electron microscopy (TEM). In 20 PSX suspect and 3 pre-PSX capsulotomy specimens, TEM revealed a precapsular layer (0.1-11 microns in thickness) composed of microfibrils, amorphous material, and granular inclusions. The incidence of this fibrillar layer was significantly higher (p = 0.001) in PSX suspect and pre-PSX eyes than in controls (5 positive). Ultrastructural and immunohistochemical similarities of the fibrillar surface network in PSX suspect and typical PSX specimens indicate that the precapsular layer may represent a precursor of PSX. The beginning PSX process in the eye is obviously indicated by certain clinical signs.