Feasibility and repeatability of ocular biometry measured with IOLMaster 700 in a large population-based study.

PURPOSE: To evaluate the feasibility and repeatability of IOLMaster 700 biometry measurements in an adult population. Furthermore, to assess the value of the Quality Indicators (QIs) provided by the device. METHOD: As part of the large population-based Leipzig Research Centre for Civilization Diseases (LIFE) Adult-Study, randomly selected participants from Leipzig, Germany were evaluated with the ZEISS IOLMaster 700. Age range was 26-85 years, with 53% of participants above 70 years of age. Axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and keratometry (K) were assessed in 1767 right eyes. Measurements were repeated twice and in a subset of 1331 eyes, three times. Measurement feasibility was evaluated for three levels; successful, with warnings and failed, using the inbuilt QIs. Repeatability was assessed as within-subject standard deviation (SD) and repeatability limits were calculated. RESULTS: First measurement success rate for phakic eyes was over 99% for AL, CCT, ACD, over 98% for LT and over 97% for K. K had 16% eyes with warnings and the recommendation to repeat the measurement. Excluding the measurements with warnings resulted in a reduction of mean SD for AL from 48 to 4 µm and for mean K from 0.08 to 0.04 D. Repeatability for phakic eyes was 8 µm for AL, CCT, ACD and LT and 2.3 µm for CCT; 0.07 D and 0.12 D for mean K and delta K, respectively, for phakic cases without warnings (two measurements). CONCLUSIONS: In our population-based sample, the IOLMaster 700 collected data for AL, CCT, ACD, LT and K from the vast majority of eyes. Considering the built-in QIs improved the measurement variability substantially. Repeatability measurements indicate that clinically meaningful changes can be detected reliably with this instrument.

Soemmerring's Rings Developed around IOLs, in Human Donor Eyes, Can Present Internal Transparent Areas.

Soemmerring's rings consist of a ring of lens epithelial derived cells that grow along the periphery of an aphakic lens capsule, or around an intraocular lens. These rings when visualized frontally, appear opaque, however, in some cases the cells that compose these rings are organized in the same fashion as those in normal transparent adult lenses. Thus, our purpose was to test whether any part of the adult Soemmerring's ring could be transparent and how this related to morphological factors. To study this, 16 Soemmerring's rings were extracted from donor eye globes. After imaging, they were thickly sectioned sagittally in order to analyze the degrees of transparency of different areas. All samples were also histologically analyzed using alpha smooth muscle actin, Vimentin, wheat germ agglutinin and DAPI. Our results showed that many samples had some transparent areas, mostly towards the center of their cross-section. Of the factors that we analyzed, only lens fiber organization at the bow region and an increased area of mature lens fiber cells had a significant relation to the degree of transparency at the center. Thus, we can conclude that as Soemmerring's rings mature, they can develop organized and transparent areas of lens cells.

Ocular biometry in children and adolescents from 4 to 17 years: a cross-sectional study in central Germany.

PURPOSE: To evaluate ocular biometry in a large paediatric population as a function of age and sex in children of European descent. METHODS: Children were examined as part of the LIFE Child Study (Leipzig Research Centre for Civilization Disease), a population-based study in Leipzig, Germany. Altogether, 1907 children, aged from 4 to 17 years, were examined with the Lenstar LS 900. Data from the right eye was analysed for axial length, central corneal thickness, flat and steep corneal radii, aqueous depth, lens thickness and vitreous depth. Wavefront-based autorefraction was employed for analysis. RESULTS: Axial length increased in girls from 21.6 mm (4 years) up to 23.4 mm (17 years); this increase (0.174 mm per year) was statistically significant up to age 14 (23.3 mm). Axial length increased in boys from 22.2 mm (4 years) up to 23.9 mm (17 years); this increase (0.178 mm per year) was statistically significant up to age 10 (23.3 mm). No change was observed for central corneal thickness (average: girls 550 µm; boys 554 µm). Corneal curvature in girls was somewhat flatter at age 4 (7.70 mm) compared to age 10 (7.78 mm), whereas it was constant in boys (7.89 mm). Aqueous depth at age 4 was 2.73 mm for girls and 2.86 mm for boys, with the same rate of increase per year (girls: 0.046 mm; boys: 0.047 mm) from age 4 to 10. At age 17, aqueous depth was 3.06 mm in girls and 3.20 mm in boys. Lens thickness was reduced from age 4 (3.75 mm) to age 10 (3.47 mm) in girls and from age 4 (3.73 mm) to age 10 (3.44 mm) in boys, with the same rate of decrease per year of 0.046 and 0.047 mm, respectively. At age 17, lens thickness was 3.52 mm in girls and 3.50 mm in boys. Vitreous depth at age 4 was 14.51 mm for girls and 15.08 mm for boys; with 0.156 mm (girls) or 0.140 mm (boys) increase per year until age 14 (girls: 16.08 mm; boys: 16.48 mm). At age 17, vitreous depth was 16.29 mm in girls and 16.62 mm in boys. CONCLUSIONS: Eye growth (axial length) in girls showed a lag of about four years compared to boys. Aqueous depth increase matches the lens thickness decrease from ages 4 to 10 years in girls and boys. Lens thickness minimum is reached at 11 years in girls and at 12 years in boys. All dimensions of the optical ocular components are closely correlated with axial length. These data may serve as normative values for the assessment of eye growth in central European children and will provide a basis for monitoring refractive error development.

Feasibility and repeatability of ocular biometry measured with Lenstar LS 900 in a large group of children and adolescents.

PURPOSE: To evaluate the feasibility and repeatability of Lenstar LS 900 biometry measurements in a paediatric population. METHODS: Children were examined as part of the LIFE Child Study (Leipzig Research Centre for Civilization Diseases), a population-based study in Leipzig, Germany. Altogether, 1917 children, aged from 3.5 to 17.5 years, were assessed with the Haag Streit Lenstar LS 900. Three consecutive measurements of the right eye were analysed for axial length, central corneal thickness, anterior chamber depth, aqueous depth, lens thickness and flat and steep corneal radii. The number of successful measurements and repeatability were evaluated for each parameter and three age bands (3.5 to 6.5 years, 6.5 to 10.5 years and 10.5 to 17.5 years). RESULTS: Best measurement feasibility was found for axial length and central corneal thickness (91% to 100%), followed by flat and steep corneal radii (86% to 100%), anterior chamber and aqueous depth (76% to 92%) and lens thickness (50% to 81%), with higher numbers for older children. Repeatability values (in mm) were: axial length 0.025 to 0.035; central corneal thickness 0.003 to 0.027; aqueous depth 0.024 to 0.058; anterior chamber 0.024 to 0.054; lens thickness 0.034 to 0.067. An overall trend showed better repeatability for older children, especially for central corneal thickness, aqueous depth and lens thickness. CONCLUSIONS: For ocular biometry in the paediatric population, axial length, central corneal thickness, flat and steep corneal radii can be measured very reliably even in children from 4 years old onward using the Lenstar LS 900. Lens thickness can be quantified in a limited number of younger children. Repeatability was high for all variables investigated. Repeatability improved with age, reaching adult values in the adolescent age band. Established repeatability limits can be applied in future studies as a quality parameter.

Deformations and Ruptures in Human Lenses With Cortical Cataract Subjected to Ex Vivo Simulated Accommodation.

Purpose: Human cortical opacities are most commonly accompanied by changes in lens fiber structure in the equatorial region at the lens nucleus-cortex interface. Cortex and nucleus have different elastic properties, which change with age. We therefore subjected ex vivo lenses to simulated accommodation and studied the internal deformations to better understand the mechanism of cortical cataract formation. Methods: Nine human donor lenses (33-88 years old) were tested using a bespoke radial stretching device for anterior eye segments. Seven of the lenses exhibited cortical cataracts. The other two lenses, without cataract, were used as controls. Frontal and cross-sectional images of the lens obtained during stretching facilitated measurements on equatorial lens diameter and central lens thickness in the stretched and unstretched states. Results: Stretching caused the lens equatorial diameter to increase in all cases. Conversely, the lens central thickness showed no systematic variation during stretching. For four of the lenses with cortical cataract, ruptures were observed during stretching at the nucleus-cortex boundary adjacent to the cortical cataracts. Ruptures were not observed in the control lenses or in the three other lenses with cortical cataract. Conclusions: Internal ruptures can occur in aged ex vivo lenses subjected to simulated disaccommodation. These ruptures occur at the nucleus-cortex interface; at this location, a significant stiffness discontinuity is expected to develop with age. It is hypothesized that ruptures occur in in vivo lenses during accommodation-or attempted accommodation.

Causes of corneal transplant failure: a multicentric study.

PURPOSE: To identify the causes of failure of the different surgical corneal graft techniques: penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), Descemet stripping automated endothelial keratoplasty (DSAEK) and Descemet membrane endothelial keratoplasty (DMEK). METHODS: This multicentric retrospective study enrolled a consecutive cohort of patients who had undergone any type of keratoplasty between 2001 and 2016. The clinical data were obtained from the patient's medical records, following ethical guidelines, permissions and data protection. The main outcome measured in the study was the cause of graft failure, defined as any irreversible loss of graft transparency capable of compromising vision. The main causes of graft failure were classified as follows: (A) primary graft failure (PGF), (B) immunological rejection, (C) non-rejection (which includes endothelial decompensation without rejection, IOP elevation/glaucoma, diseases of the ocular surface, recurrence of the primary disease, wound dehiscence/hypotonia and trauma, among others) and (D) specific causes of lamellar keratoplasty failure. A descriptive study of the obtained data was carried out. The distribution of the causes of failure was evaluated according to the type of corneal transplant. RESULTS: Our research included a cohort of 571 keratoplasty failures, of which 509 met the inclusion criteria. The analysis of the causes of the PK failure showed that immunological allograft rejection represented the main cause, with 28.2% of the failures, followed by surface diseases (17.8%) and endothelial decompensation without rejection (17.3%). For the PK re-grafts group, the main cause of failure was immunological allograft rejection (34.0%), followed by diseases of the ocular surface (18.5%). For the DALK group, the failures mainly occurred due to surface diseases such as limbal stem cell insufficiency, infectious keratitis, keratolysis or persistent epithelial defect (37.8%). However, the main reason for failure in the DSAEK group was endothelial decompensation without rejection (31.9%) while primary graft failure was the main cause of failure in the DMEK group (64.1%). CONCLUSION: The main reason for failure in PK was immunological allograft rejection, both in primary and secondary transplants. The leading causes for failure were diseases of the ocular surface in the DALK population, endothelial decompensation without rejection in DSAEK and primary graft failure in DMEK.

The Chemokine Receptors Ccr5 and Cxcr6 Enhance Migration of Mesenchymal Stem Cells into the Degenerating Retina.

Cell therapy approaches hold great potential for treating retinopathies, which are currently incurable. This study addresses the problem of inadequate migration and integration of transplanted cells into the host retina. To this end, we have identified the chemokines that were most upregulated during retinal degeneration and that could chemoattract mesenchymal stem cells (MSCs). The results were observed using a pharmacological model of ganglion/amacrine cell degeneration and a genetic model of retinitis pigmentosa, from both mice and human retinae. Remarkably, MSCs overexpressing Ccr5 and Cxcr6, which are receptors bound by a subset of the identified chemokines, displayed improved migration after transplantation in the degenerating retina. They also led to enhanced rescue of cell death and to preservation of electrophysiological function. Overall, we show that chemokines released from the degenerating retinae can drive migration of transplanted stem cells, and that overexpression of chemokine receptors can improve cell therapy-based regenerative approaches.

Correction: Bacterial nanocellulose as a corneal bandage material: a comparison with amniotic membrane.

Correction for 'Bacterial nanocellulose as a corneal bandage material: a comparison with amniotic membrane' by Irene Anton-Sales et al., Biomater. Sci., 2020, 8, 2921-2930, DOI: .

Bacterial nanocellulose as a corneal bandage material: a comparison with amniotic membrane.

Corneal trauma and ulcerations are leading causes of corneal blindness around the world. These lesions require attentive medical monitoring since improper healing or infection has serious consequences in vision and quality of life. Amniotic membrane grafts represent the common solution to treat severe corneal wounds. However, amniotic membrane's availability remains limited by the dependency on donor tissues, its high price and short shelf life. Consequently, there is an active quest for biomaterials to treat injured corneal tissues. Nanocellulose synthetized by bacteria (BNC) is an emergent biopolymer with vast clinical potential for skin tissue regeneration. BNC also exhibits appealing characteristics to act as an alternative corneal bandage such as; high liquid holding capacity, biocompatibility, flexibility, natural - but animal free-origin and a myriad of functionalization opportunities. Here, we present an initial study aiming at testing the suitability of BNC as corneal bandage regarding preclinical requirements and using amniotic membrane as a benchmark. Bacterial nanocellulose exhibits higher mechanical resistance to sutures and slightly longer stability under in vitro and ex vivo simulated physiological conditions than amniotic membrane. Additionally, bacterial nanocellulose offers good conformability to the shape of the eye globe and easy manipulation in medical settings. These excellent attributes accompanied by the facts that bacterial nanocellulose is stable at room temperature for long periods, can be heat-sterilized and is easy to produce, reinforce the potential of bacterial nanocellulose as a more accessible ocular surface bandage.

Histological comparison of in vitro and in vivo development of peripheral posterior capsule opacification in human donor tissue.

In order to study the mechanisms involved in the development of posterior capsule opacification (PCO) we compared in vivo developed PCO with PCO formed in tissue culture with focus on the periphery of the lens capsule to evaluate lens regeneration potential. We studied three human tissue groups: Cultured lens capsules after mock cataract surgery (n = 6, 30 days), lens capsules from donors that had previously undergone cataract surgery (IOL capsules) (n = 12) and intact lenses (n = 6). All samples were stained with Vimentin, alpha Smooth Muscle Actin, Picro Sirius Red (for collagen) and Paired box protein (Pax6). We found that cultured capsules and less developed IOL capsules consisted mainly of monolayers of mesenchymal cells, while more developed IOL capsules, contained lens epithelial cells (LECs), globular cells and lens fiber cells. Many IOL capsule samples expressed collagen I and III in areas where cells were in contact with the IOL. Pax6 had a similar dispersed distribution in less developed IOL capsules and cultured capsules, while more developed IOL capsules and intact lenses, concentrated Pax6 in LECs at the equatorial lens bow. The similarities between cultured capsules and less developed IOL capsules indicate that our in vitro developed PCO is comparable to early in vivo developed PCO. The similar morphology of more developed IOL capsules and intact lenses seems to indicate an attempt at lens regeneration.

Academic factors in medical recruitment: evidence to support improvements in medical recruitment and retention by improving the academic content in medical posts.

There is a major problem with medical recruitment and retention in the UK. The 2018 General Medical Council (GMC) report 'The state of medical education and practice in the UK' has indicated that a high proportion of doctors are thinking of either giving up medical practice or reducing their hours in the next 3 years. If this trend continues the shortage of doctors in the UK will increase despite a modest increase in the supply of doctors.This paper investigates the evidence that increasing the academic component of medical posts may help retain doctors in practice by providing experience and support in an area of medical practice, which appears to fulfil a significant number of doctors' aspirations. The paper shows that this aspect of medical practice is poorly represented in medical workforce strategic thinking and should be considered as an integral aspect of policy and practice in medical workforce delivery.

Risk factors for graft failure after penetrating keratoplasty.

The objective of our study was to define principal risk factors for graft failure in patients who underwent penetrating keratoplasty (PK).Retrospective data obtained from a cohort of 895 penetrating keratoplasties performed between 2001 and 2006 were analysed. Recipient related factors, graft characteristics, and surgical technique were assessed in a univariate analysis and with a multivariate proportional hazard model to detect principal risk factors for definitive graft failure.Multivariate analysis showed clear significance for diagnosis and number of previous grafts and border line significance for the oldest donor age group. Patients with keratoconus had the best 10-year survival estimate (95%), followed by endothelial and stromal dystrophies (both 55%), infectious leukomas (49%), trauma (33%) and chemical burns (14%). Primary PK grafts had a survival rate of 81%, second grafts of 33% and third or more grafts of 16%. Overall 10-year survival estimate based on univariate analysis was found to be 65%.In conclusion, we found that primary diagnosis and previous graft failures in the recipient are the most important risk factors of graft failure after a PK.

Osteo-odonto-, Tibial bone and Boston keratoprosthesis in clinically comparable cases of chemical injury and autoimmune disease.

PURPOSE: To compare anatomical and functional results between three types of keratoprosthesis (KPro) in chemical injury and autoimmune disease. METHODS: 70 clinically comparable cases were included as follows: Boston KPro Type 1 25 eyes, osteo-odonto-keratoprosthesis (OOKP) 23 eyes, Tibial bone KPro 22 eyes. Survival times for anatomical and functional success were evaluated with Kaplan-Meier estimations and Log-rank tests. KPro exchange was considered a complication, not as failure. RESULTS: Prosthesis retention in chemical injury group at 5 years was 86% for OOKP, 100% for Tibial bone KPro, and 65% for Boston KPro (p = 0.09), while in the autoimmune disease group it was 66% for Tibial bone KPro and 50% for Boston KPro (p = 0.19; OOKP only one case). Functional success in the chemical injury group at 5 years was 86% for OOKP, 84% for Tibial bone KPro and 71% for Boston KPro (p = 0.38), while in the autoimmune group, it was 44% for Tibial bone KPro and 15% for Boston KPro (p = 0.15; OOKP only one case). The post-operative complications in all groups were: retinal detachment, vitreous hemorrhage, endophthalmitis, retro-prosthetic membrane, uncontrolled glaucoma, the last two being more common in Boston KPro. CONCLUSIONS: For both diagnoses, chemical injury and autoimmune diseases, there was a tendency for better long-term anatomical and functional results with Tibial bone KPro followed by OOKP and Boston KPro Type 1. However, these results were not statistically significant.

Cortical Cataract and Refractive Error.

PURPOSE: To evaluate the relationship between the presence of cortical cataract and accommodation effort, using refractive error as a proxy. METHODS: Patients between 50 and 90 years, scheduled for cataract surgery, were selected with the help of a photographic database. Nuclear and cortical cataract were graded and patients grouped having no cataract, pure cortical, mixed or pure nuclear cataract. Refraction data at the time of the photograph was converted to estimated spherical equivalent refractive error each patient would have had at the age of 45 years. RESULTS: From the initial 239 eyes from 239 patients, cases with myopia below -6.5 dpt and hyperopia above 6.5 dpt were excluded, resulting in 199 cases for final analysis. Eyes with no cataract showed the lowest median refractive error (-3.65 dpt), followed by the pure nuclear group (-2.69 dpt). The median refractive error for pure cortical (-0.23 dpt) and mixed cataracts (-0.87 dpt) were close to emmetropia. Cortical cataracts were found in 37% of myopes, 82% of emmetropes, and 85% of hyperopes. CONCLUSION: Emmetropes and hyperopes tend to develop more cortical cataract than myopes. These cortical cataracts might be caused by shear stress inside the crystalline lens due to accommodation efforts at the time of onset of presbyopia.

Prevention of posterior capsule opacification through intracapsular hydrogen peroxide or distilled water treatment in human donor tissue.

In order to determine whether posterior capsule opacification after cataract surgery, could be delayed or inhibited through the application of hydrogen peroxide (H2O2) or distilled water (H2Od),we extracted lens capsules from 25 human donor eye globes. Samples were treated for 5 min with either 30 mM H2O2 or H2Od or used as controls, and cultured for one month, during which dark field and tilt illumination photos were taken. These were used to observe and quantify, time until cellular growth and confluence on the posterior capsule. After culture, histological sections were stained for H&E, α-SMA, Ki-67 and vimentin and evaluated. We prevented cellular growth in 50% of H2Od and 58% H2O2 of treated samples. The overall prevention of cell growth compared to cultured controls was significant for both treatments while there was no significant difference between them. In the cases where cellular growth was not prevented, both treatments significantly delay cellular growth. Until day 28 none of the treated samples of either type that had shown growth reached total confluence. All cultured controls reached total confluence before treated samples (median = day 11.5). Also, histologically, there was a clear morphological difference between cultured controls and treated samples.

Comparison of long-term results between osteo-odonto-keratoprosthesis and tibial bone keratoprosthesis.

PURPOSE: To compare the anatomical and the functional results between osteo-odonto-keratoprosthesis (OOKP) and keratoprosthesis using tibial bone autograft (Tibial bone KPro). METHODS: We reviewed the charts of 258 patients; 145 had OOKP whereas 113 had Tibial bone KPro implanted. Functional success was defined as best corrected visual acuity ≥0.05 on decimal scale and anatomical success as retention of the keratoprosthesis lamina. Kaplan-Meier survival curves were calculated for anatomical and functional survival as well as to estimate the probability of post-op complications. RESULTS: The anatomical survival for both KPro groups was not significantly different and was estimated as 67% for OOKP and 54% for Tibial bone KPro at 10 years after surgery. There was also no difference found after subdividing for primary diagnosis groups such as chemical injury, thermal burn, trachoma and all autoimmune cases combined. Estimated functional survival at 10 years post-surgery was 49% for OOKP and 25% for Tibial bone KPro, which was significantly different. The probability of patients with Tibial bone KPro developing one or more post-operative complications at 10 years after surgery (65%) was significantly higher than those with OOKP (40%). Mucous membrane necrosis and retroprosthetic membrane formation were more common in Tibial bone KPro than OOKP. CONCLUSION: Both types of autologous biological KPro, OOKP and Tibial bone KPro, had statistically similar rate of keratoprosthesis extrusion. Although functional success rate was significantly higher in OOKP, it may have been influenced by a better visual potential in the patients in this group.

Anterior lens capsule strains during simulated accommodation in porcine eyes.

Experimental protocols have been developed to measure the spatial variation of the mechanical strains induced in the lens capsule during ex vivo lens stretching. The paper describes the application of these protocols to porcine lenses. The deformations and mechanical strains developed in the anterior capsule during each experiment were determined using full field digital image correlation techniques, by means of a speckle pattern applied to the lens surface. Several speckling techniques and illumination methods were assessed before a suitable combination was found. Additional data on the cross section shape of the anterior lens surface were obtained by Scheimpflug photography, to provide a means of correcting for lens curvature effects in the determination of the strains developed in the plane of the capsule. The capsule strains in porcine lenses exhibit non-linear behaviour, and hysteresis during loading and unloading. Peripheral regions experience higher magnitude strains than regions near the lens pole. The paper demonstrates the successful application of a procedure to make direct measurements of capsule strains simultaneously with ex vivo radial lens stretching. This experimental technique is applicable to future investigations on the mechanical characteristics of human lenses.

Hyperspectral Raman imaging of neuritic plaques and neurofibrillary tangles in brain tissue from Alzheimer's disease patients.

Neuritic plaques and neurofibrillary tangles are crucial morphological criteria for the definite diagnosis of Alzheimer's disease. We evaluated 12 unstained frontal cortex and hippocampus samples from 3 brain donors with Alzheimer's disease and 1 control with hyperspectral Raman microscopy on samples of 30 × 30 µm. Data matrices of 64 × 64 pixels were used to quantify different tissue components including proteins, lipids, water and beta-sheets for imaging at 0.47 µm spatial resolution. Hierarchical cluster analysis was performed to visualize regions with high Raman spectral similarities. The Raman images of proteins, lipids, water and beta-sheets matched with classical brain morphology. Protein content was 2.0 times, the beta-sheet content 5.6 times and Raman broad-band autofluorescence was 2.4 times higher inside the plaques and tangles than in the surrounding tissue. The lipid content was practically equal inside and outside. Broad-band autofluorescence showed some correlation with protein content and a better correlation with beta-sheet content. Hyperspectral Raman imaging combined with hierarchical cluster analysis allows for the identification of neuritic plaques and neurofibrillary tangles in unstained, label-free slices of human Alzheimer's disease brain tissue. It permits simultaneous quantification and distinction of several tissue components such as proteins, lipids, water and beta-sheets.

Validation of the Nuclear Cataract Grading System BCN 10.

PURPOSE: To evaluate a new nuclear cataract grading system which is intended as a surgical guidance system to predict lens hardness before cataract surgery. METHODS: The new BCN 10 grading system consists of frontal and cross-sectional slit-lamp images of human eye lenses, ranging from a completely transparent lens nucleus to a totally black nuclear cataract. Validation was done with 9 observers for 110 cases. Two modalities were applied, and observers were asked to use only whole digits and then half digits for grading. RESULTS: Repeatability with regard to test-retest differences showed a mean limit of agreement of 1.70 for whole digits and 1.32 for half digits. The absolute test-retest difference was close to zero for low as well high degrees of cataracts. Reliability for the entire group of 9 observers yielded an intraclass correlation coefficient which was within the same confidence interval, i.e., 0.991-0.995, for whole digits and half digits. CONCLUSIONS: BCN 10 grading repeatability was not affected by the severity of the cataract. It showed very good repeatability. Repeatability was significantly higher when the observers used half digits compared to whole digits. Reliability was found to be very good as well, independently of the use of whole or half digits.

Osteokeratoprosthesis Using Tibial Bone: Surgical Technique and Outcomes.

PURPOSE: To analyze the anatomical and functional results of keratoprosthesis using tibial bone autograft. METHODS: We reviewed 113 charts of patients who underwent tibial bone osteokeratoprothesis implantation at the Centro de Oftalmologia Barraquer. Kaplan-Meier survival curves with 95% confidence interval were calculated for functional success, defined as best corrected visual acuity (BCVA) ≥0.05 on the decimal scale, and for anatomical success, defined as retention of the keratoprosthesis lamina. Multivariate analysis was used to test the impact of clinical factors on anatomical and functional survival rates. RESULTS: Based on Kaplan-Meier analyses, tibial bone keratoprosthesis 5-year and 10-year anatomical survival rates were 69.5% and 53.5%, respectively. Functional survival rate at 5 years was 33% and at 10 years was 19.2%. Considering primary diagnosis, chemical burn had better anatomical and functional survival rates than autoimmune or infectious diseases. Patient age did not have a significant effect on keratoprosthesis survival rates. About 48.7% of the patients who underwent surgery had complications: keratoprosthesis extrusion, glaucoma, retinal detachment and buccal mucosa necrosis were the most frequent ones. CONCLUSION: Half of the patients with tibial bone KPro had retained the keratoprosthesis after 10 years post-surgery and one-fifth of them had visual acuity of 0.05 or better at the same period. Considering that these patients have no other way to recover their vision either because they have no canine tooth or their buccal or dental conditions are not adequate for OOKP, this modified surgery is their only hope.