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Previous studies have reported that heparan sulfate proteoglycans (HSPGs) promote amyloid-beta peptide and tau fibrillization in Alzheimer disease (AD) and provide resistance against proteolytic breakdown. We compared the expression levels of 17 HSPG core proteins in 18 AD cases and 6 controls. RT-PCR was used to analyze transcription levels. Immunohistochemistry was performed to localize HSPGs in the brain tissue. We detected expression of all HSPG genes investigated. SDC1, GPC3, and CD44v3 showed the lowest levels of expression, while SDC3 and GPC1 showed the highest. Remarkably, SDC4 and SRGN were overexpressed in most of the areas analyzed. Immunohistochemistry revealed the presence of both SDC4 and SRGN mostly associated with tau and amyloid-β pathology throughout the AD brains. In conclusion, in view of the involvement of HSPGs in AD pathology, especially SDC4 and SRGN, there would seem to be a relationship between the regulation of core protein expression and the pathological features suggesting HSPGs are potential inducers of the disease., (© 2020 American Association of Neuropathologists, Inc. All rights reserved.)

Purpose: To evaluate the endothelial cell loss in patients with iris-claw phakic lenses (Artisan®) in a long-term follow-up., Methods: We analyzed the medical records of patients who had undergone iris-claw phakic lens implantation and who had at least 5 years of follow-up., Results: We included 67 eyes with myopic errors (follow-up 9.6 ± 3.0 years) and 10 eyes with mixed astigmatism or hyperopic errors (follow-up 8.8 ± 2.5 years). The mean total endothelial density loss at the last follow-up visit was 18.5% ± 17.0% and 10.5% ± 12.3%, respectively. 29.9% of the eyes in the myopic group and 20% in the hyperopic group lost more than 25% of the preoperative endothelial cell density. During the postoperative follow-up period, 60.8% of the eyes in the myopic group and 40% of the eyes in the hyperopic group lost a higher percentage than the expected physiological loss. Two eyes in the myopic group (3.0%) had a final cell density of less than 1200 cells/mm 2 . None of the variables studied had a statistically significant association with the percentage of annual endothelial loss in the postoperative period. Three phakic lenses were explanted: two by cataract and one by cataract and severe decrease of the endothelial density (862 cells/mm 2 )., Conclusions: There is a significant endothelial cell loss in a low percentage of the eyes with Artisan® lenses in the long term, and it can decrease to critical levels. Periodic endothelial density evaluations are required for these patients. The selection criteria of surgical candidates could be reevaluated.

Purpose: To describe the case of a patient with a recurrent large myopic macular hole (MH), who was successfully treated with a plasma rich in growth factors (PRGF) membrane., Case Report: A 71-year-old patient presented a myopic MH in his right eye. One month later, pars plana vitrectomy with internal limiting membrane (ILM) peeling was performed, achieving closure of the MH. Three months later a recurrence was observed (700 µm) without visual acuity (VA) improvement. A new surgery was carried out placing an autologous PRGF-membrane into the MH, and performing a fluid-gas exchange at the end of the surgery. After two months of follow-up, the MH was completely closed, obtaining the anatomic recovery of the foveal depression, and improving the VA to 0.1. No adverse reactions were associated with the use of PRGF and there were no new recurrences of the MH in a follow-up period of six months., Conclusion: The use of PRGF-membrane can be used as adjunctive therapy in the surgical repair of recurrent large myopic MHs, thus improving anatomic and visual outcomes., Competing Interests: The authors report no conflicts of interest in this work.

Background: Glycosaminoglycans (GAGs) are essential in many infections, including recurrent bacterial respiratory infections, the main cause of mortality in cystic fibrosis (CF) patients., Methods: Using a cellular model of healthy and CF lung epithelium, a comparative transcriptomic study of GAG encoding genes was performed using qRT-PCR, and their differential involvement in the adhesion of bacterial pathogens analyzed by enzymatic degradation and binding competition experiments., Results: Various alterations in gene expression in CF cells were found which affect GAG structures and seem to influence bacterial adherence to lung epithelium cells. Heparan sulfate appears to be the most important GAG species involved in bacterial binding., Conclusions: Adherence to lung epithelial cells of some of the main pathogens involved in CF is dependent on GAGs, and the expression of these polysaccharides is altered in CF cells, suggesting it could play an essential role in the development of infectious pathology., (Copyright © 2018 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

It has recently been suggested that alterations of the layers of the retina could be a biomarker of specific mental disorders since they originate in the same embryonic layer as the brain and both are interconnected through the optic nerve. The purpose of this article is to offer a systematic review of the literature and a thematic synthesis on the current state of the alterations of the retina layers identified by optical coherence tomography in patients with schizophrenia, bipolar disorder and major depression. For this purpose, we performed a bibliographic search, a systematic review of the studies and a thematic synthesis of the reported findings. Patients with schizophrenia have more abnormal findings followed by patients with bipolar disorder, with very few findings in depression. The nerve fiber layer is the retinal layer with more abnormal findings both in schizophrenia and in bipolar disorder, while no study in major depression found alterations in it. Of the clinical parameters, the duration of the illness correlates significantly and inversely with the thickness of the different layers in all disorders. When interpreting these data, it is necessary to take into account the limitations and differences of the studies, especially the mean length of the disorders. Given that this was very different among the 3 disorders (more than doubled in the case of schizophrenia respect to major depression), the differences in the results found could be due more to the effect of the length of illness than to the disorder itself. In summary, optical coherence tomography findings are promising, since they could provide biomarkers of neurodegeneration and/or neuroprogression of both schizophrenia and bipolar disorder., (Copyright © 2019 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.)

Objective: Galenic evaluation of the process for obtaining and storing the platelet rich in growth factors PRGF-Endoret® eye drops., Method: To assess whether the PRGF-Endoret® eye drops process is aseptically obtained, a sterility test was carried out on the eye drops; the tightness of the PRGF-Endoret® eye drops containers was also analyzed. Likewise, the chemical and biological properties of the PRGF- Endoret® eye drops were evaluated after the obtaining process and storage.  Eye drop filtration tests, one cycle of freezing at -20 °C and thawing, and  eye drop stability for three and six months stored at -20 °C were included., Results: The results obtained in the sterility test showed no microbial  contamination in any of the analyzed eyedropper; tightness test showed that  100% of the eyedrop containers and the 98.4% of the plugs analyzed  remained hermetic. On the other hand, all the growth factors measured  remained constant after filtering the PRGF-Endoret® eye drops.  Furthermore, the different eye drop stability tests carried out in this study  showed no significant changes in the growth factors levels, cell proliferative  activity or in the chemical characteristics analyzed. Conclusions: The PRGF-Endoret® eye drops are obtained in a safety and aseptic manner following the guidelines issued by the Spanish Agency  for Drugs and Health Products and the Ministry of Health to obtain medicines for human use. The PRGF-Endoret® eye drops maintain their physical-chemical and biological properties after being subjected to different  storage times and temperatures., (Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.)

Meibomian gland dysfunction (MGD) is a common and chronic disorder that has a significant adverse impact on patients' quality of life. It is a leading cause of evaporative dry eye disease (DED), as meibomian glands play an important role in providing lipids to the tear film, which helps to retard the evaporation of tears from the ocular surface. MGD is also often present in conjunction with primary aqueous-deficient DED. Obstructive MGD, the most commonly observed type of MGD, is the main focus of this article. MGD is probably caused by a combination of separate conditions: primary obstructive hyperkeratinization of the meibomian gland, abnormal meibomian gland secretion, eyelid inflammation, corneal inflammation and damage, microbiological changes, and DED. Furthermore, skin diseases such as rosacea may play a part in its pathology. Accurate diagnosis is challenging, as it is difficult to differentiate between ocular surface diseases, but is crucial when choosing treatment options. Ocular imaging has advanced in recent years, providing ophthalmologists with a better understanding of ocular diseases. This review presents a literature update on the 2011 MGD workshop and an optimized approach to accurate diagnosis of MGD using currently available methods and tests. It also outlines the emerging technologies of interferometry, non-contact meibography, keratography and in vivo confocal laser microscopy, which offer exciting possibilities for the future. Selected treatment options for MGD are also discussed., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Dry eye disease (DED) results in tear film instability and hyperosmolarity, inflammation of the ocular surface and, ultimately, visual disturbance that can significantly impact a patient's quality of life. The effects on visual acuity result in difficulties with driving, reading and computer use and negatively impact psychological health. These effects also extend to the workplace, with a loss of productivity and quality of work causing substantial economic losses. The effects of DED and the impact on vision experienced by patients may not be given sufficient importance by ophthalmologists. Functional visual acuity (FVA) is a measure of visual acuity after sustained eye opening without blinking for at least 10 s and mimics the sustained visual acuity of daily life. Measuring dynamic FVA allows the detection of impaired visual function in patients with DED who may display normal conventional visual acuity. There are currently several tests and methods that can be used to measure dynamic visual function: the SSC-350 FVA measurement system, assessment of best-corrected visual acuity decay using the interblink visual acuity decay test, serial measurements of ocular and corneal higher order aberrations, and measurement of dynamic vision quality using the Optical Quality Analysis System. Although the equipment for these methods may be too large or unaffordable for use in clinical practice, FVA testing is an important assessment for DED., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To assess the long-term outcomes of implanting intrastromal corneal ring segments (ICRS) in paracentral keratoconic eyes., Methods: 58 eyes with paracentral keratoconus with coincident refractive, keratometric, and comatic axes were evaluated. Uncorrected (UDVA) and corrected (CDVA) distance visual acuity and refractive errors were recorded before and at all follow-up visits. The postoperative follow-up was 5 years. Patients were divided into two groups: group I (30 years old or younger) and group II (more than 30 years old)., Results: The mean UDVA (logMAR) rose from a preoperative 0.83 ± 0.31 to a five-year postoperative 0.42 ± 0.33 ( P < 0.0001). The mean CDVA varied from 0.16 ± 0.17 to 0.11 ± 0.18 ( P = 0.0003). Both the UDVA and CDVA were stable over the postoperative period in both groups ( P > 0.05). The spherical equivalent and the refractive cylinder declined steeply after ICRS implantation in both groups ( P < 0.001), and were stable over the postoperative period ( P > 0.05). The keratometric values were also stable over the postoperative follow-up., Conclusion: Ferrara-type ICRS implantation in keratoconus that meets the characteristics of the sample under study reduces the refractive error at the same time as it improves postoperative UDVA and CDVA six months after surgery and that these results remain stable over five years of follow-up.

Corneal injuries are one of the most frequently observed ocular diseases, leading to permanent damage and impaired vision if they are not treated properly. In this sense, adequate wound healing after injury is critical for keeping the integrity and structure of the cornea. The goal of this work was to assess the potential of polymeric nanocapsules, either unloaded or loaded with cyclosporine A or vitamin A, alone or in combination with mitomycin C, for the treatment of corneal injuries induced by photorefractive keratectomy surgery. The biopolymers selected for the formation of the nanocapsules were polyarginine and protamine, which are known for their penetration enhancement effect. The results showed that, following topical instillation to a mouse model of corneal injury, all the nanocapsule formulations, either unloaded or loaded with cyclosporine A or vitamin A, were able to stimulate corneal wound healing. In addition, the healing rate observed for the combination of unloaded protamine nanocapsules with mitomycin C was comparable to the one observed for the positive control Cacicol®, a biopolymer known as a corneal wound healing enhancer. Regarding the corneal opacity, the initial grade of corneal haze (>3) induced by the photorefractive keratectomy was more rapidly reduced in the case of the positive control, Cacicol®, than in corneas treated with the nanocapsules. In conclusion, this work shows that drug-free arginine-rich (polyarginine, protamine) nanocapsules exhibit a positive behavior with regard to their potential use for corneal wound healing.

Aim: To evaluate corneal parameters measured with a dual Scheimpflug analyzer in keratoconus patients implanted with intrastromal corneal ring segments (ICRS)., Methods: Fifty eyes of 40 keratoconus patients had Ferrara ICRS implantation from November 2010 to April 2014. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refraction, keratometry, asphericity, elevation, pachymetry, root mean square (RMS), spherical aberration and coma were studied. All patients were evaluated using a dual Scheimpflug system., Results: The mean follow-up time after the procedure was 12.7mo. The mean UCVA improved from 0.82 to 0.31 (P<0.001); the mean BCVA improved from 0.42 to 0.05 (P<0.0001), the mean spherical refraction changed from -3.06±3.80 D to -0.80±2.5 D (P<0.0001) and the mean refraction astigmatism reduced from -4.51±2.08 D to -2.26±1.18 D (P<0.0001). The changes from preoperative to postoperative, in parameters of the anterior and posterior surface of the cornea, were statistically significant except the elevation posterior at the apex of the cornea and posterior asphericity., Conclusion: The implantation of Ferrara ICRS induces changes in both anterior and posterior surfaces of the cornea.

Myopia is a multifactorial visual refraction disease, in which the light rays from distant objects are focused in front of retina, causing blurry vision. Myopic eyes are characterized by an increased corneal curvature and/or ocular axial length. The prevalence of myopia has increased in recent decades, a trend that cannot be attributed exclusively to genetic factors. Low and middle income countries have a higher burden of refractive error, which we propose could be a consequence of a shorter exposure time to a westernized lifestyle, a phenomenon that may also explain the rapid increase in cardiometabolic diseases, such as diabetes, among those populations. We suggest that interactions between genetic, epigenetic and a rapidly changing environment are also involved in myopia onset and progression. Furthermore, we discuss several possible mechanisms by which insulin resistance may promote abnormal ocular growth and myopia to support the hypothesis that insulin resistance and hyperinsulinemia are involved in its pathogenesis, providing a link between trends in myopia and those of cardiometabolic diseases. There is evidence that insulin have direct ocular growth promoting effects as well an indirect effect via the induction of insulin-like growth factors leading to decreases insulin-like growth factor-binding protein, also implicated in ocular growth., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Meibomian gland dysfunction (MGD) is the most frequent cause of dry eye disease (DED). Eyelid inflammation, microbial growth, associated skin disorders as well as potentially severe corneal complications culminate to make MGD a complex multifactorial disorder. It is probable that MGD is a heterogeneous condition arising from any combination of the following five separate pathophysiological mechanisms: eyelid inflammation, conjunctival inflammation, corneal damage, microbiological changes and DED resulting from tear film instability. The pathogenesis of both MGD and DED can be described in terms of a 'vicious circle': the underlying pathophysiological mechanisms of DED and MGD interact, resulting in a double vicious circle. The MGD vicious circle is self-stimulated by microbiological changes, which results in increased melting temperature of meibum and subsequent meibomian gland blockage, reinforcing the vicious circle of MGD. Meibomian gland blockage, dropout and inflammation directly link the two vicious circles. MGD-associated tear film instability provides an entry point into the vicious circle of DED and leads to hyperosmolarity and inflammation, which are both a cause and consequence of DED. Here we propose a new pathophysiological scheme for MGD in order to better identify the pathological mechanisms involved and to allow more efficient targeting of therapeutics. Through better understanding of this scheme, MGD may gain true disease status rather than being viewed as a mere dysfunction., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Purpose: To evaluate corneal wound healing in the hen animal model after additive surgery with an intracorneal ring segment (ICRS)., Methods: We implanted one ICRS in each eye of 76 hens. In control group 1 (n = 22 hens), the stromal channel was prepared but no ICRS was inserted. In control group 2 (n = 2 hens), no surgery was performed. Animals were randomly separated into groups and euthanized after clinical follow-up of 4 and 12 hours, 1, 2, 3, and 7 days, and 1, 2, 3, 4, and 6 months. Corneas were stained with hematoxylin-eosin. Apoptosis was measured by terminal uridine nick end-labeling assays. Cell proliferation and myofibroblast-like differentiation were assayed by BrdU and α-smooth muscle actin immunofluorescence microscopy. Stromal matrix changes were documented by electron microscopy., Results: Epithelial and stromal cell apoptosis around the ICRS-implanted and control group 1 eyes peaked at 12 hours, but continued for 72 hours. In ICRS-implanted eyes, epithelial and stromal proliferation was present at 12 and 24 hours, respectively, and peaked at 7 days and 72 hours, respectively. Some proliferation in the ICRS-implanted group continued through the 6-month follow-up, and myofibroblast-like cells differentiated one to three months after ICRS implantation. The segments rotated within the stroma as the limbal inferior angle approached the epithelium., Conclusions: Wound healing after ICRS implantation in hen corneas was similar to that of other corneal surgical wounds in stages. However, there were some specific features related to the small size of the epithelial wound and the device permanently implanted inside the cornea.

Purpose: To study the attachment and growth of human corneal cells on keratin-chitosan membranes. The end goal is to develop a bioengineered cornea based on this material., Methods: Keratin-chitosan membranes were prepared as previously described by Tanabe et al., 2002. Briefly, 7.15 mg/cm2 of keratin dialysate was mixed with 10 wt% chitosan solution and 20 wt% glycerol. The solution was cast into a silicone mold and dried at 50ºC for 36 hours. Eyes were attained from a local eye bank after penetrant-keratoplastic surgery. Human epithelial, stromal and endothelial cells were obtained of the limbal, stromal and endothelial regions. Cells were cultured on keratin-chitosan membranes, as well as on plastic dishes as controls. When cultured cells reached confluence, they were fixed, incubated with primary antibodies (E-cadherin, cytokeratin high molecular weight (CK), vimentin and Na+/K+ ATPase) and visualized by indirect immunocytochemistry., Results: Epithelial, stromal and endothelial cells were able to attach and grow on keratin-chitosan membranes. All the cells maintained their morphology and cellular markers, both in the membrane and on the culture plate. Epithelial cells stained positively for CK and E-cadherin. A positive vimentin stain was observed in all stromal cells, while endothelial cells were positive for vimentin and Na+/K+ ATPase, but negative for E-cadherin., Conclusions: Keratin-chitosan membranes have been shown to be a good scaffold for culturing epithelial, stromal and endothelial corneal cells; therefore, future applications of keratin-chitosan membranes may be developed for reconstruction of the cornea.

Purpose: The etiology of keratoconus (KC) and the factors governing its progression are not well understood. It has been suggested that this disease might be caused by biochemical alterations in the cornea; changes in the expression profiles of human aqueous humor (hAH) proteins have been observed in some diseases. To gain a new insight into the molecular mechanisms of KC pathology, we examined the hAH proteomes of those in the advanced stages of this disease. We used a high-throughput mass spectrometry approach to compare hAH protein expression in patients with KC and in control subjects., Methods: Aqueous humor samples were acquired from five keratoconus patients during keratoplasty surgery and from five myopic control subjects during phakic intraocular lens implantation. Quantitative mass spectrometry analysis using spectral counting was performed to determine the relative amounts of hAH proteins in the samples from KC patients and control individuals., Results: All KC patients included in the study presented severe keratoconus (K2 >52 D), and slit-lamp examination revealed microfolds in Descemet's membrane, without clinical signs of hydrops. We found significant differences between the expression levels of 16 proteins in the two groups. In KC samples, seven proteins were overexpressed and nine were underexpressed in comparison with the control group. Gene ontology analysis revealed that these deregulated proteins are implicated in several biologic processes, such as the regulation of proteolysis, responses to hypoxia, and responses to hydrogen peroxide, among others., Conclusions: The protein expression profiles in hAH from KC patients and myopic control subjects differ significantly. This result suggests that some components of the hAH proteome are involved in this disease. Further in-depth analysis of the hAH proteome should provide a better understanding of the mechanisms governing the pathophysiology of KC.

Thyroid orbitopathy is the most prevalent non-thyroid symptom in Graves' syndrome. It has a high incidence and particularly affects young women. Smoking is clearly involved in its development and progress, and in its response to different treatments. This autoimmune condition usually has a benign course, independent from hyperthyroidism, but its severe, progressive forms represent a major therapeutic challenge. Clinical evaluation poses great difficulties, as there is no truly objective rating scale representing disease activity. New molecular or inflammation markers may prove to be useful in this regard. This review reports new findings about its pathophysiology and the different techniques used for treatment over time. Discussion particularly focuses on the immunomodulatory role of radiotherapy, as well as on its role together with corticosteroids., (Copyright © 2014 SEEN. Published by Elsevier España, S.L.U. All rights reserved.)

Purpose: To assess the visual and refractive outcomes of femtosecond laser-assisted implantation of Ferrara-type intrastromal corneal ring segments (ICRS) in post-penetrating keratoplasty (PKP) eyes., Setting: Instituto Oftalmológico Fernández-Vega, Oviedo, Spain., Design: Cohort study., Methods: Patients with previous PKP had ICRS implantation after femtosecond laser tunnel creation. The uncorrected (UDVA) and corrected (CDVA) distance visual acuities and residual refractive errors were recorded before and 6 months after ICRS implantation. The power vector method was used to analyze refractive errors preoperatively and postoperatively., Results: This study enrolled 32 eyes of 30 patients. The mean UDVA (Snellen decimal) changed from 0.16 ± 0.15 (SD) preoperatively to 0.43 ± 0.28 postoperatively (P<.0001). Postoperatively, the UDVA was 20/40 or better in 40.6% of eyes. The mean CDVA was 0.67 ± 0.22 preoperatively and 0.80 ± 0.19 postoperatively (P<.0001). Postoperatively, the CDVA was better than 20/40 in 96.9% of eyes and 20/25 or better in 56.2% of eyes. By 6 months postoperatively, no eye had lost more than 2 lines of CDVA, 4 eyes lost 1 line, 6 eyes had no change, 9 eyes gained 1 line, and 13 eyes gained 2 or more lines. The safety index at 6 months was 1.20. The spherical equivalent and astigmatism components were significantly reduced after ICRS implantation (P<.04)., Conclusion: Intrastromal corneal ring segment implantation using the femtosecond laser may be a good alternative for high astigmatism correction in post-PKP eyes., (Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the sensitivity and specificity of a PCR-strip system based on reverse dot blot for detection of MUC5AC mRNA in corneal epithelium samples from patients with limbal stem cell deficiency (LSCD), and to determine the correlation with clinical diagnosis., Methods: We obtained 87 corneal impression cytology (IC) samples from 55 subjects (37 patients clinically diagnosed with LSCD and 18 control subjects). Total RNA was extracted from each IC sample and retrotranscribed to cDNA. MUC5AC mRNA transcript was amplified by a customized RT-PCR assay and detected in PCR strips based on reverse dot blot hybridization and in agarose gels. Conjunctival IC samples were used as positive controls., Results: Forty-four of 45 corneal IC samples obtained from patients clinically diagnosed with LSCD were positive for MUC5AC, whereas 34 of 42 corneal ICs from healthy subjects were negative for MUC5AC. Four healthy corneas were found MUC5AC positive, and four rendered inconclusive results. A correlation of 91.4% (P < 0.001) between molecular testing and clinical diagnosis was found. The overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the PCR-strip system were 98%, 89%, 92%, and 97%, respectively., Conclusions: Corneal epithelium MUC5AC transcript detection by reverse dot blot PCR-strip is a highly sensitive technique for LSCD diagnosis. The test results strongly correlate with clinical diagnosis of characterized LSCD cases. The PCR-strip system may be used for early detection, and for the detection of mild cases of LSCD, and constitutes an objective clinical tool for the monitoring of treatments and surgical decisions.

Purpose: To determine the effects of intravitreal atropine on scleral growth in the form-deprived chick as an experimental model of myopia., Methods: Five groups of five chicks were studied from day 0-12 post-hatching. One group remained untreated (C), and four were form-deprived by monocular light diffusers to induce myopia. Two groups (RL and A) wore diffusers for 9 days, and the other two groups (D and D + A) wore diffusers throughout the study. Group D received no further treatment (myopia positive control). Groups A and D + A received intravitreal injections of atropine for days 9-12. Measurements of refractive error and axial length were performed on days 0, 9, and 12. Sclera changes were assessed in cartilaginous and fibrous layers by histological analysis., Results: All form-deprived eyes had a myopic refractive error on day 9. All atropine-treated groups were hyperopic on day 12. The effect of atropine was most evident in Group D + A in which diffusers were maintained throughout treatment and changes in refractive error were statistically significant. The observed changes in axial length were in line with the changes in refractive error. The scleral fibrous layer thickness increased, and the sceral cartilaginous layer underwent a slight thinning compared to Group D, the myopia positive control., Conclusions: If the signals that induce growth remain during atropine treatment, morphological changes in sclera are produced: the scleral fibrous layer thickened, and the sceral cartilaginous layer thinned. These changes resulted in refractive error recovery, and the ocular growth was stopped. The data suggested the atropine was acting throughout the scleral fibrous layer., (Ophthalmic & Physiological Optics © 2012 The College of Optometrists.)

Background:   To evaluate the clinical safety and efficacy of implanted Ferrara intrastromal corneal ring segments in a large sample of patients with ectatic corneal disease., Design:   Retrospective, consecutive case series., Samples:   A total of 1073 eyes of 810 patients consecutively operated from January 2006 to July 2008 were evaluated., Methods:   Two groups were created according to the type of ring implanted: Group 1 - patients implanted with the 160° of arc ring - and Group 2 - patients implanted with the 210° of arc ring., Main Outcome Measures:   Uncorrected visual acuity, best-corrected visual acuity, keratometry, asphericity and pachymetry at the thinnest point of the cornea. All patients were evaluated using a corneal tomography (Pentacam, Oculus, Inc., Lynnwood, WA, USA)., Results:   For Group 1 patients, uncorrected visual acuity increased to 20/80, best-corrected visual acuity increased to 20/40, asphericity decreased to -0.35, spherical equivalent decreased to -2.26 D and keratometry decreased to 45.72 D (P < 0.001 for each compared with preoperative values). For Group 2 patients, uncorrected visual acuity increased to 20/130, best-corrected visual acuity increased to 20/60, asphericity decreased to -0.56, spherical equivalent decreased to -4.14 D and keratometry decreased to 48.10 D (P < 0.001 for each compared with preoperative values). The 210° intrastromal corneal ring segments reduced keratometry and asphericity more than the 160° intrastromal corneal ring segments did. The complication rate was 3.82%., Conclusions:   Ferrara intrastromal corneal ring segments implantation is safe and effective and has a low complication rate. It can effectively reduce the corneal steepening and improve uncorrected visual acuity and best-corrected visual acuity in patients with keratoconus., (© 2011 The Authors. Clinical and Experimental Ophthalmology © 2011 Royal Australian and New Zealand College of Ophthalmologists.)

Purpose: To evaluate the clinical outcomes of implantation of Ferrara intrastromal corneal ring segments (ICRS) in patients with astigmatism after penetrating keratoplasty (PKP)., Setting: Private clinic, Belo Horizonte, Brazil., Design: Retrospective consecutive case series., Methods: Chart records of post-PKP patients who had ICRS implantation from May 2005 to September 2009 were retrospectively reviewed. The following parameters were studied: corrected distance visual acuity (CDVA), keratometry (K) values, spherical equivalent (SE), spherical refractive error, corneal topographic astigmatism, minimum K, and maximum K., Results: The study evaluated 59 eyes (54 patients). The mean CDVA (logMAR) improved from 0.45 ± 0.17 (SD) (range 0.18 to 1.00) to 0.30 ± 0.17 (range 0.00 to 1.00). The mean SE was -6.34 ± 3.40 diopters (D) (range 0.37 to -16.50 D) preoperatively and -2.66 ± 2.52 D (range 0.87 to -10.50 D) postoperatively. The mean spherical refractive error decreased from -7.10 ± 3.07 D (range 2.15 to 16.68 D) preoperatively to -3.46 ± 2.05 D (range 0.88 to 10.79 D) postoperatively. No patient lost visual acuity. The mean corneal topographic astigmatism decreased from 3.37 ± 1.51 D preoperatively to 1.69 ± 1.04 D postoperatively. The mean maximum K value decreased from 48.09 ± 2.56 D to 44.17 ± 2.67 D and the mean minimum K value, from 44.90 ± 2.54 D to 42.46 ± 2.63 D. All changes were statistically significant (P<.0001)., Conclusion: Intrastromal corneal ring segments effectively reduced corneal cylinder in patients with astigmatism after PKP., (Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess the tolerance and side effects of azithromycin eyedrops at the ocular surface after corneal refractive surgery in an experimental animal model., Methods: The effect of azithromycin eyedrops was evaluated in hen corneas that underwent laser-assisted in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) surgery in 1 eye, using the fellow eye (not manipulated) as a control. Animals were treated bid 3 days prior to surgery and 3 days after surgery with T1225 1.5% azithromycin eyedrops or saline eyedrops (balanced salt solution), or were left untreated as a control. Clinical course and cell biology (apoptosis, proliferation, and differentiation) measurements were assessed., Results: Infections were present in the following proportions of corneas operated on by LASIK: 0% treated with azithromycin, 60% treated with BSS, and 30% untreated. No corneal abscess or keratitis were present in any PRK or unmanipulated corneas. Conjunctival edema and redness were less prevalent in LASIK-operated eyes treated with azithromycin than in BSS-treated or untreated eyes and were not observed in any PRK or unmanipulated corneas. In PRK-operated eyes treated with azithromycin, a decrease was observed in the apoptosis and an increase in the stromal proliferation. There were no differences in these parameters for LASIK and unmanipulated eyes., Conclusions: Topical administration of T1225 oil-based azithromycin eyedrops was well tolerated in both unmanipulated hen corneas and those treated with corneal refractive surgery (PRK and LASIK). T1225 demonstrated a potent antibiotic effect after LASIK treatment.

Purpose: To check whether myopic LASIK induces changes on the posterior corneal surface., Methods: A Scheimpflug system (Pentacam; Oculus, GmbH, Wetzlar, Germany) was used to measure preoperative and postoperative posterior corneal topography in 27 eyes (of 14 subjects) that had undergone standard myopic LASIK surgery (attempted corrections between -1.25 and -8.50 D) and on 18 nonoperated eyes (9 subjects). A hybrid porcine-plastic eye model was developed to validate the measurement technique. Longitudinal displacement of the posterior corneal apex and changes of the apical radius of curvature and asphericity were computed., Results: Measurements on a hybrid model eye of known posterior corneal geometry showed that the measured posterior corneal radius of curvature was minimally affected by the geometry of the anterior surface. The measurements on patients showed that, on average, the only relevant (though clinically unimportant) change in radius of curvature and asphericity occurred the first day after surgery (DeltaR = -28 +/- 34 microm and DeltaQ = -0.06 +/- 0.06). No statistically significant change was observed afterward. The change in radius was more pronounced in the vertical direction than in the horizontal direction. On average, there was no significant displacement of the posterior corneal apex. Individual changes over time did not show a systematic trend across patients, and control subjects experienced changes of the same order of magnitude., Conclusions: The Pentacam Scheimpflug system can be used reliably to assess changes in the posterior corneal radius of curvature after LASIK. There is no evidence of surgically induced changes in the corneal posterior surface beyond 1 week after surgery.

Purpose: To describe the theoretical effects of cyclotorted ablations on induced aberrations and determine the limits of tolerance of cyclotorsional accuracy., Methods: A method was developed to determine the average cyclotorsion during refractive surgery without a cyclotorsion tracker. Mathematical conditions were simulated to determine the optical, visual, and absolute benefits in 76 consecutive treatments performed on right eyes. The results were evaluated as Zernike expansion of residual wavefront aberrations., Results: Ablations based purely on Zernike decomposition but with cyclotorsion applied resulted in residual aberrations of the same Zernike modes of different magnitudes and orientations, indicating that the effect of cyclotorted compensation can be analyzed by single Zernike modes in magnitude and orientation. The effect on single Zernike modes depends on angular frequency, and not on radial order. A mean of 4.39 degrees of cyclotorsion was obtained. A theoretical optical benefit was achieved in 95% of treatments, a theoretical visual benefit in 95%, and an absolute benefit in 93% compared with 89%, 87%, and 96% of treatments achieving actual benefits, respectively., Conclusions: Residual aberrations resulting from cyclotorsion depend on aberrations included in the ablation and cyclotorsional error. The theoretical impact of cyclotorted ablations is smaller than that of decentered ablations or edge effects in coma and spherical aberrations. The results are valid within a single-failure condition of pure cyclotorsional errors, because no other sources of aberrations are considered. The leap from the mathematical model to the real-world outcome cannot be extrapolated without further study.

Purpose: To develop an experimental animal model of laser in situ keratomileusis (LASIK) in hens., Methods: One hundred adult hens underwent a 60-microm corneal flap followed by -4 diopter excimer laser ablation. Surgical technique, clinical course, and pathology correlations are presented., Results: Sixty percent of animals had a successful LASIK outcome according to clinical observations. Pathology showed the integrity of Bowman's layer and homogeneous flap in all eyes with good clinical outcomes. Flap complications such as buttonholes (5%), free-flaps (2%), and slipped flaps (3.4%) occurred with the surgical technique. Corneal abscess (2.9%) was also present. Loss of transparency was noted in 26.4%, which correlates with epithelial ingrowth detected by light histology study., Conclusions: An experimental animal model of LASIK was successfully developed in adult hens. This model could be useful in the study of wound healing and pharmacological modulation after LASIK in an animal with Bowman's layer.