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Human amniotic membrane has been widely used in ophthalmology for decades, particularly in ocular surface reconstruction. This article reviews its mechanism of action, surgical principles and clinical applications. The fate of transplanted amniotic membrane in the eye and its limitations will also be addressed.

Purpose. This paper aims to review the morphological and functional characteristics of patients affected by familial amyloid polyneuropathy (FAP), with greater focus on type I and its progression after liver transplantation. We also analyse therapeutic options for the ophthalmic manifestations.Methods. The literature from 2002 through 2015 was reviewed, with a total of 45 articles studied, using the key terms related to amyloidosis and its therapeutic approaches. Information was collated, evaluated, critically assessed, and then summarised in its present form.Pathophysiology and Treatment. FAP results from mutation of the transthyretin gene, with Val30Met being the most frequent substitution. The symptoms are those typical of a sensorimotor autonomic neuropathy and can be halted with liver transplantation. Nowadays there are new medical therapies that delay the progression of the systemic neuropathy. However, there are still no options to avoid ocular disease.Conclusion. The main ocular manifestations in patients with FAP type I are amyloid deposition in the vitreous, dry eye, and secondary glaucoma. Despite liver transplantation, eye synthesis of amyloid persists and is associated with progressive ocular manifestations, which require continued ophthalmologic follow-up. New therapeutic strategies are therefore needed, particularly to target the ocular synthesis of the abnormal protein.

A 42-year-old woman presented with chronic history of left red eye for more than 12 months, treated with difference topical medication but without response. Ocular external examination demonstrated a firm palpable mass in the medial portion of the lower eyelid and slit-lamp evaluation of the lesion showed an ulcerated conjunctival nodule, keratin secretor. CT of the orbits revealed left-sided orbital mass located anteriorly, inferiorly and medially in the orbit, adjacent to the globe and orbit walls. Incisional biopsy of the lesion was consistent with invasive squamous cell carcinoma of the conjunctiva. As the tumour had no response to initial adjuvant systemic chemotherapy, exenteration of left orbit was performed due to advanced disease.

Purpose To differentiate the plasma metabolomic profile of patients with age related macular degeneration (AMD) from that of controls, by Nuclear Magnetic Resonance (NMR) spectroscopy. Methods Two cohorts (total of 396 subjects) representative of central Portugal and Boston, USA phenotypes were studied. For each cohort, subjects were grouped according to AMD stage (early, intermediate and late). Multivariate analysis of plasma NMR spectra was performed, followed by signal integration and univariate analysis. Results Small changes were detected in the levels of some amino acids, organic acids, dimethyl sulfone and specific lipid moieties, thus providing some biochemical information on the disease. The possible confounding effects of gender, smoking history and age were assessed in each cohort and found to be minimal when compared to that of the disease. A similar observation was noted in relation to age-related comorbidities. Furthermore, partially distinct putative AMD metabolite fingerprints were noted for the two cohorts studied, reflecting the importance of nutritional and other lifestyle habits in determining AMD metabolic response and potential biomarker fingerprints. Notably, some of the metabolite changes detected were noted as potentially differentiating controls from patients diagnosed with early AMD. Conclusion For the first time, this study showed metabolite changes in the plasma of patients with AMD as compared to controls, using NMR. Geographical origins were seen to affect AMD patients´ metabolic profile and some metabolites were found to be valuable in potentially differentiating controls from early stage AMD patients. Metabolomics has the potential of identifying biomarkers for AMD, and further work in this area is warranted.

Purpose The purpose of this study was to develop an algorithm to automatically standardize the brightness, contrast, and color balance of digital color fundus photographs used to grade AMD and to validate this algorithm by determining the effects of the standardization on image quality and disease grading. Methods Seven-field color photographs of patients (>50 years) with any stage of AMD and a control group were acquired at two study sites, with either the Topcon TRC-50DX or Zeiss FF-450 Plus cameras. Field 2 photographs were analyzed. Pixel brightness values in the red, green, and blue (RGB) color channels were adjusted in custom-built software to make the mean brightness and contrast of the images equal to optimal values determined by the Age-Related Eye Disease Study (AREDS) 2 group. Results Color photographs of 370 eyes were analyzed. We found a wide range of brightness and contrast values in the images at baseline, even for those taken with the same camera. After processing, image brightness variability (brightest image–dimmest image in a color channel) was reduced 69-fold, 62-fold, and 96-fold for the RGB channels. Contrast variability was reduced 6-fold, 8-fold, and 13-fold, respectively, after adjustment. Of the 23% images considered nongradable before adjustment, only 5.7% remained nongradable. Conclusions This automated software enables rapid and accurate standardization of color photographs for AMD grading. Translational Relevance This work offers the potential to be the future of assessing and grading AMD from photos for clinical research and teleimaging.

Objective To determine the efficacy and safety of azithromycin 1.5% eye drops in a paediatric population with purulent bacterial conjunctivitis. Patients and methods This was a multicentre, international, randomised, investigator-masked study in 286 children with purulent discharge and bulbar conjunctival injection. Patients received either azithromycin 1.5% eye drops (twice daily for 3 days) or tobramycin 0.3% eye drops (every 2 h for 2 days, then four times daily for 5 days). Clinical signs were evaluated on day (D) 0, 3 and 7, and cultures on D0 and D7. The primary variable was the clinical cure (absence of bulbar conjunctival injection and discharge) on D3 in the worse eye for patients with positive cultures on D0. Results 286 patients (mean age 3.2 years; range 1d ay–17 years) were included; 203 had positive cultures on D0. Azithromycin was superior to tobramycin in clinical cure rate on D3 (47.1% vs 28.7%, p=0.013) and was non-inferior to tobramycin on D7 (89.2% vs 78.2%, respectively). Azithromycin treatment eradicated causative pathogens, including resistant species, with a similar resolution rate to tobramycin (89.8% vs 87.2%, respectively). These results were confirmed in a subgroup of patients younger than 24 months old. Conclusions Azithromycin 1.5% eye drops provided a more rapid clinical cure than tobramycin 0.3% eye drops in the treatment of purulent bacterial conjunctivitis in children, with a more convenient twice-a-day dosing regimen.

PURPOSE The purpose of this study was to evaluate the efficacy of cysteamine eyedrops 0.1136% (new formulation, now stable at room temperature without the need for refrigeration for up to 2 months) for the treatment of cystine crystals in the cornea using slit lamp biomicroscopy and confocal microscopy. METHODS A 20-year-old woman with infantile cystinosis, with a history of kidney transplantation at age 10, was studied. She applied cysteamine eyedrops (0.1136%) 10 times a day (a new formulation, now stable at room temperature without the need for refrigeration for up to 2 months, was prepared for compassionate use). The density of the cystine crystals in the cornea was evaluated using slit lamp biomicroscopy and confocal microscopy (Heidelberg Retina Tomograph 2 equipped with the Rostock Module for the Cornea). RESULTS The deposits were absent in the surface epithelium and basal cells of the central cornea before and after treatment. We found crystals mainly in the anterior and medium stroma; they had various shapes; were intracellular, rectangular, or fusiform; and showed hyperreflectivity. The posterior stroma showed lower density of the crystals. No deposits in the endothelium were found. Therapy with cysteamine eyedrops reduced the density of the crystals and lessened the photophobia. CONCLUSION Confocal microscopy is a valuable technique to study cystine crystals of the cornea in vivo. Cysteamine eyedrops appear to be very useful in the treatment of these crystals, especially for photophobic complaints.

A mathematical model which simulates drug delivery through the cornea, from a therapeutic lens to the anterior chamber of the eye, is proposed. The model consists of three coupled systems of partial differential equations linked by interface conditions: drug diffusion in the therapeutic lens; diffusion and metabolic consumption in the cornea; diffusion, convection and metabolic consumption in the anterior chamber of the eye. The dependence of intraocular pressure on the obstruction of the trabecular mesh and the production rate of aqueous humor by the ciliary body is modeled. The therapeutic effects of drugs that act on the trabecular mesh or on the ciliary body are analysed. Comparisons between topical administration and drug delivery from a therapeutic lens are included.

Aim To perform Descemet stripping automated endothelial keratoplasty (DSAEK) using a novel technique to obtain very thin (

Purpose To compare visual function after bilateral implantation of multifocal Lentis Mplus LS-312 (Group A) or Acrysof Restor SN6AD1 (Group B) intraocular lenses (IOLs). Setting Ophthalmology Unit, Centro Hospitalar e Universitario de Coimbra, and Visual Neuroscience Laboratory, IBILI, Faculty of Medicine, University of Coimbra, Coimbra, Portugal. Design Comparative case series. Methods Patients between 49 years and 76 years had bilateral cataract surgery with multifocal IOL implantation. Patients were evaluated preoperatively and 3 months postoperatively for distance, intermediate, and near visual acuities; static photopic and mesopic contrast sensitivity; and visual acuity under a glare source using the Metrovision contrast sensitivity platform. Color vision was evaluated with the Cambridge Colour Test. Results Group A comprised 56 eyes and Group B, 44 eyes. Visual and refractive results were comparable between the 2 groups. Photopic contrast sensitivity was significantly better in Group B at intermediate (2.2 cycles per degree [cpd] and 3.4 cpd) and high (7.1 cpd and 23.6 cpd) spatial frequencies. Under low mesopic conditions (0.08 candelas/m2), differences were significant at 1.1 cpd and 2.2 cpd spatial frequencies. There were no differences in visual acuity under a glare source or in color vision. Conclusions Both IOLs provided good distance, intermediate, and near visual acuities. Visual acuity under a glare source and color vision were similar in the 2 groups. However, photopic and low mesopic contrast sensitivities were better in Group B, particularly for intermediate spatial frequencies, which are important for night driving. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Purpose To evaluate the use of a femtosecond laser combined with a microkeratome in the preparation of posterior corneal disks for Descemet stripping automated endothelial keratoplasty (DSAEK). Methods This experimental study involved ultrathin DSAEK tissue preparation of 22 donor corneas unsuitable for transplantation. The first cut was performed with an Intralase® FS60 laser and the second cut with a Moria CBm 300-μm microkeratome. The thickness of the first cut was modified for each cornea to obtain a final graft thickness of less than 110 μm. Precut and postcut central pachymetry were performed with an ultrasonic pachymeter. Central endothelial cell density (ECD) was calculated before and 24 hours after tissue preparation. Results Final graft thickness was 105.0 ± 26.1 (SD) μm (range 65–117). The mean microkeratome head cut thickness was 324.5 ± 10.9 μm (range 310–345). Precut and postcut ECDs averaged 2250 ± 222 and 2093 ± 286 cells/mm2, respectively, representing 6.9% of cell loss. No corneas were perforated. Conclusions Femtosecond FS60 lasers and Moria CBm 300-μm microkeratomes can be used sequentially to prepare consistently thin DSAEK grafts with no irregular cuts or cornea perforations.

Neuroplasticity refers to the ability of the brain to reorganize the function and structure of its connections in response to changes in the environment. Adult human visual cortex shows several manifestations of plasticity, such as perceptual learning and adaptation, working under the top-down influence of attention. Plasticity results from the interplay of several mechanisms, including the GABAergic system, epigenetic factors, mitochondrial activity, and structural remodeling of synaptic connectivity. There is also a downside of plasticity, that is, maladaptive plasticity, in which there are behavioral losses resulting from plasticity changes in the human brain. Understanding plasticity mechanisms could have major implications in the diagnosis and treatment of ocular diseases, such as retinal disorders, cataract and refractive surgery, amblyopia, and in the evaluation of surgical materials and techniques. Furthermore, eliciting plasticity could open new perspectives in the development of strategies that trigger plasticity for better medical and surgical outcomes.

Purpose: To evaluate the efficacy and safety of standard photodynamic therapy with verteporfin at 48 months in patients with chronic central serous chorioretinopathy. Methods: A retrospective, multicenter, interventional case series analysis in patients with chronic central serous chorioretinopathy, treated with standard photodynamic therapy, and with ≥4 years of follow-up. Evaluations were performed every 3 months in the first year, every 6 months in the second year, and thereafter annually. Optical coherence tomography was performed in all visits. Fluorescein angiography and indocyanine green angiography were performed at baseline and thereafter as necessary. Retinal thickness on optical coherence tomography was measured manually, evaluating central macular thickness and neural retina thickness. Main outcomes included the evolution of best-corrected visual acuity, the resolution of subretinal fluid, documented with optical coherence tomography, the number of treatments, and the evaluation of neural retina thickness during the 48 months of follow-up. Results: The study included 46 eyes of 42 patients, 38 men (90.4%) and 4 women (9.5%), with mean age of 49.19 ± 9.9 years (range, 32-70 years), and the minimal follow-up period was 48 months (mean, 56.8 ±10.3 months). Subretinal fluid was observed in all the included eyes at baseline, and 10 eyes (21.7%) had intraretinal diffuse or cystoid fluid. Concerning the mean best-corrected visual acuity, a statistically significant improvement (P < 0.01, Student t-test) was registered from 58.8 ± 18.3 letters at baseline to 66.9 ± 18.6 letters at 48th month. A complete resolution of subretinal fluid was achieved in 93.4%, and resolution of intraretinal fluid occurred in all 10 cases at 48 months. Neural retina thickness remained stable during the 48 months of follow-up (163.8 ± 47 μm at baseline and 163.8 ± 46 μm at 48 months). The mean number of treatments was 1.08 ± 0.3. No systemic or ocular side effects were registered. Conclusion: Standard photodynamic therapy with verteporfin was effective and safe in chronic central serous chorioretinopathy treatment with a significant improvement in the long term, both anatomic and visual, without inducing additional retinal atrophy or systemic adverse effects.

Microperfusion techniques were used to characterize in vitro the fluorescein transport and fluid movement across isolated diabetic rabbit retinal vessels. Unbranched segments of afterioles of alloxan-induced diabetic rabbits were isolated and cannulated on a microperfusion apparatus. Movement of 3 H-inulin, the reference tracer, and 14 C-fluorescein, the test tracer, across the vascular walls was studied using microperfusion techniques adapted by us to study vascular permeability. The diabetic retinal vessels showed a fluid flux from bath to lumen of 3·6 ± 0·6 nl min -1 mm -1 with perfusion rates of 7·1 ± 0·3 nl min -1 . This value was 43% ( P ≤ 0·05) lower when compared with normal values obtained in previous work. Bath to lumen fluorescein fluxes were 2·1 ± 0·5 and 7·6 ± 1·6 × 10 -12 mol min -1 mm, -1 , for fluorescein concentrations of 0·87 × 10 -4 and 1·5 × 10 -4 M, respectively. These values are 23% ( P ≤ 0·05) and 38·7% ( P ≤ 0·05), respectively, lower when compared to values obtained from normal retinal vessels. Probenecid, a competitive inhibitor of organic anion transport, added to the bath, had no effect. Increasing bath concentrations of fluorescein caused increasing fluid flux from bath to lumen, and again, probenecid added to the bath has no effect. These results show a significant decrease of fluorescein transport and of net fluid flux across diabetic retinal vessel walls from outside into the lumen, suggesting that in experimental alloxan-induced diabetes there is an early, probably functional, involvement of the retinal vessels in the initial alteration of the blood-retinal barrier (BRB).

PURPOSE To evaluate the long-term safety and efficacy of photodynamic therapy in the treatment of choroidal neovascularization associated with pathologic myopia. METHODS Five-year retrospective study of 43 consecutive eyes of 36 patients with juxtafoveal or subfoveal choroidal neovascularization and pathologic myopia treated with photodynamic therapy. RESULTS Mean best-corrected visual acuity changed from 20/125 +1 letter (0.78 logarithm of the minimum angle of resolution) at baseline to 20/100 (0.70 logarithm of the minimum angle of resolution) at 5 years (P = 0.122). Final best-corrected visual acuity improved in 53.5% of the eyes, remained stable in 11.6%, and decreased in 34.9%. A visual acuity gain of ≥3 lines occurred in 32.6% of the eyes, and a visual acuity decrease of ≥3 lines was registered in 20.9% of the cases at 5 years. Only patient's age and initial visual acuity showed to have a significant predictive value for the final visual acuity outcome (P = 0.024 and P = 0.002, respectively). CONCLUSION Photodynamic therapy with verteporfin may increase the chance of stabilizing and improving vision in patients with choroidal neovascularization from pathologic myopia at 5 years. Better results were found in younger patients (

To analyze photorefractive keratectomy (PRK) outcomes in myopia and myopic astigmatism correction using the WaveLight Allegretto Wave Eye-Q(®) excimer laser system (WaveLight Laser Technologie AG, Erlangen, Germany). 222 eyes of 151 patients underwent PRK (mean age 33.5 ± 6.8 years). Pre-operative best spectacle-corrected visual acuity (BSCVA) ranged from 0.4 to -0.1 logMAR (mean -0.03 ± 0.06). Mean spherical equivalent (SE) was -3.29 ± 1.20 D. Efficacy, predictability and safety were evaluated. Minimum follow-up was 3 months. Accountability at 3 and 6 months was 100 and 54 %, respectively (median follow-up 5 months, mean 5.2 ± 2.6 months). At 3 months, mean uncorrected visual acuity (UCVA) was -0.02 ± 0.07 logMAR, BSCVA -0.03 ± 0.05 logMAR, efficacy index 0.98 and safety index 1.02. UCVA was ≥20/16 in 40.1 %, ≥20/20 in 86.5 % and ≥20/25 in 98.2 %. Mean SE was -0.02 ± 0.20 D. Residual refractive error was ± 0.13 D in 81.5 %, ± 0.25 D in 88.7 % and ± 0.50 D in 97.7 %. At 6 months, outcomes were similar: mean UCVA was -0.02 ± 0.07 logMAR, BSCVA -0.03 ± 0.06 logMAR, efficacy index 1.00 and safety index 1.03. UCVA was ≥20/16 in 43.7 %, ≥20/20 in 86.6 % and ≥20/25 in 96.6 %. Mean SE was -0.02 ± 0.17 D. Residual refractive error was ± 0.13 D in 86.6 %, ± 0.25 D in 93.3 % and ± 0.50 D in 98.3 %. Refractive stability was achieved at 3 months. No patient lost more than one line of BSCVA. There were no retreatments. The WaveLight Allegretto Wave Eye-Q is effective, predictable and safe in low-to-moderate myopia and myopic astigmatism PRK correction.

To evaluate and characterize the clinical features of corneal ectasia after myopic laser in situ keratomileusis (LASIK) considering internal astigmatism and corneal aberrations and their correlation with other clinical data.Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain.Retrospective comparative case series.In this multicenter study, eyes were divided into 2 groups. The study group comprised eyes that had corneal ectasia after myopic LASIK. The control group comprised eyes that had successful LASIK to correct high myopia. The clinical outcomes were analyzed and compared. Internal astigmatism was calculated using vectorial analysis.The study enrolled 91 eyes (48 study group; 40 control group) of 81 patients (age 18 to 67 years). Uncorrected and corrected (CDVA) distance visual acuities and the refractive status were significantly worse in the study group (P ≤ .01). Corneas in the study group had a significantly higher steepest keratometry (K) reading and a more negative central asphericity (P.01). Internal astigmatism and corneal aberrations were also significantly higher in the study group (P.01). The CDVA was significantly correlated with primary spherical aberration (r = -0.561, P =.01) and primary coma root mean square (r = 0.451, P =.04). Age was significantly correlated with mean K (r = -0.44, P =.01) and internal astigmatism (r = -0.34, P =.04).Larger levels of internal astigmatism and anterior corneal aberrations leading to a visual deterioration were present in eyes with corneal ectasia after myopic LASIK.No author has a financial or proprietary interest in any material or method mentioned.

PURPOSE: The purpose of this study was to evaluate the safety and efficacy of intravitreal ranibizumab after 12 months in the treatment of choroidal neovascularization secondary to pathologic myopia. METHODS: This was a prospective, multicenter, consecutive, nonrandomized, interventional case series. The study included 34 eyes of 32 patients with choroidal neovascularization secondary to pathologic myopia; 13 eyes had previous photodynamic therapy, and 21 eyes had no previous treatment. The patients were followed for > or = 12 months. Best-corrected visual acuity, optical coherence tomography, and the presence of metamorphopsia were assessed monthly. RESULTS: Mean visual acuity improved 8 letters from baseline to 12-month follow-up, and the difference was statistically significant (P < 0.001): 100% of the eyes lost or = 3 lines, 44% improved > or = 2 lines, 65% improved > or = 1 line, and 79% improved > or = 0 lines. Central retinal thickness decreased significantly from baseline to the 12-month follow-up (P < 0.01). A mean of 3.6 treatments were performed during the 12-month follow-up, and no systemic or ocular side effects were registered during that time. CONCLUSION: One-year results of intravitreal ranibizumab for myopic choroidal neovascularization are very promising. Additional prospective studies are necessary to better determine long-term efficacy and safety.

espanolObjetivo: Revisar el resultado de los trasplantes de limbo (TL) realizado en pacientes con Sindrome de insuficiencia limbica (SIL) en el contexto de varias enfermedades de la superficie ocular. Materiales y metodos: Se realizo un estudio retrospectivo y multicentrico (cinco centros) de los TL realizados entre 1996 y 2004. Los datos fueron recogidos por el mismo investigador, en una base de datos especialmente disenada para el estudio. Se considero como «exito» del TL a la ausencia de: defectos epiteliales, inflamacion y recurrencia del pterigion cuando este fue la causa del TL. Resultados: Se analizaron un total de 72 TL realizados en 61 pacientes (65 ojos) con tiempo de seguimiento de 20,8 meses (DS 23,5; rango, 3-115). Hubo 33 hombres y 28 mujeres, con una media de 55,8 anos (DS: 15,6; rango, 20-89). Se realizaron 58 (80.6%) TL autologos (40 pterigion, 12 causticaciones, tres iatrogenicas, dos infecciones virales, una neoplasia) y 14 (19,4%) TL alogenicos de donante cadaver (siete inflamaciones inmunes, seis causticaciones, uno iatrogenico). Todos los pacientes a los que se les realizo TL alogenicos recibieron inmunosupresion sistemica. Al final del seguimiento, 48 (66,7%) TL se consideraron un exito. Este porcentaje fue del 81,0% (47/58) en los TL autologos y del 7,1% (1/14) en los TL alogenicos. El porcentaje de exito tambien dependio de la etiologia, siendo alto en los casos de pterigion (80,0%) y menor en las patologias inmunologicas (14,3%). Conclusiones: El TL autologo es preferible al alogenico, pues la tasa de fracasos disminuye notablemente y, ademas, se evita el uso de inmunosupresion oral mantenida. Ademas, el pronostico es siempre peor en los casos de patologia inflamatoria inmune. El TL autologo parece ser una buena eleccion para el tratamiento del pterigion recurrente, aunque se necesitan estudios prospectivos que corroboren estos resultados. EnglishPurpose: To report the results of limbal transplantation (LT) in patients with limbal stem cell deficiency (LSCD) in the context of ocular surface diseases. Materials and methods: A multicenter (5 centers) retrospective case series analysis of patients who underwent LT between 1996 and 2004 was performed. Data were collected by the same researcher using a customized database. Success was defined by the absence of a persistent corneal epithelial defect, on-going inflammation or recurrence of a pterygium. Results: Data from 72 LT performed in 61 patients (65 eyes) with a mean follow-up of 20.8 months (SD 23.5; range, 3-115) were analyzed. There were 33 males and 28 females with a mean age of 55.8 years (SD: 15.6; range, 20-89). Fifty-eight (80.6%) LT were autografts (40 pterygia, 12 alkali burns, 3 iatrogenic cases, 2 viral infections, 1 neoplasia case) and 14 (19.4%) were allografts from cadaveric donors (7 immune-based disorders, 6 alkali burns, 1 iatrogenic case); all patients receiving allografts also received systemic immunosuppression. Of the total number of LT, 48 (66.7%) were successful. This proportion increased to 81.0% (47/58) when autografts were used. However, only 7.1% (1/14) of all allografts were successful. The success rate was higher (80.0%) when performed for a pterygium and lower when done for immune-based inflammation (14.3%). Conclusion: Autograft tissue for LT is always preferable to allografts to surgically treat LSCD, as clinical success is significantly higher, and systemic immunosuppression is avoided. As expected, immune-based disorders are the most difficult cases to treat. LT has been shown to be an excellent option for recurrent pterygium, although prospective studies need to be performed to further corroborate these results.

To prospectively compare laser in situ keratomileusis (LASIK) flaps created with a femtosecond laser or a mechanical microkeratome and analyze the effect of the postoperative measurement interval on estimated femtosecond flap thickness using ultrasound (US) pachymetry.Department of Ophthalmology, University Hospital of Coimbra, and Coimbra Surgical Centre, Coimbra, Portugal.Flaps were created with a Hansatome Zero Compression microkeratome (Group 1), Zyoptix XP keratome (Group 2), or IntraLase 60 kHz femtosecond laser (Groups 3 and 4). Flap thickness was determined by intraoperative US pachymetry immediately after flap creation in Groups 1, 2, and 3. In Group 4, pachymetry was performed 20 minutes after the laser treatment. The main outcome measures were flap thickness and deviation from the target value.Eighty patients had LASIK for myopia or myopic astigmatism. The mean flap thickness was 149.1 microm +/- 24.9 (SD) in Group 1, 124.7 +/- 23.8 microm in Group 2, 143.1 +/- 18.4 microm in Group 3, and 115.5 +/- 12.5 microm in Group 4. The difference in flap thickness between Group 3 and Group 4 was statistically significant (P.01). The flap thickness deviation from the target value was 22.8 microm in Group 1, 19.0 microm in Group 2, 26.1 microm in Group 3, and 10.4 microm in Group 4.Results indicate that the time of measurement after femtosecond affects the estimated flap thickness. Waiting 20 minutes after laser treatment permitted easier separation and may eliminate the effect of variable corneal dehydration on flap measurement by subtraction pachymetry.

This review evaluates the outcomes of intrastromal corneal ring segment (ICRS) implantation for the treatment of keratoconus considering a new grading system based on the preoperative visual impairment of the patient. Additionally, a five-year follow-up analysis of patients with stable and progressive keratoconus is performed in order to assess the long term stability of the surgical procedure. Corrected distance visual acuity decreased statistically significantly in patients with mild keratoconus (P < 0.01) but statistically significantly increased in all other grades (P < 0.05). The improvement in visual acuity and the decrease of keratometric and aberrometric values were stable throughout a long period of time in patients with stable keratoconus. In patients with progressive form keratoconus, a significant improvement was found immediately after the procedure, however clinically relevant regression greater than 3 D was observed at the end of the follow up period.

PURPOSE: To analyze the outcomes of intracorneal ring segment (ICRS) implantation for the treatment of keratoconus based on preoperative visual impairment. DESIGN: Multicenter, retrospective, nonrandomized study. METHODS: A total of 611 eyes of 361 keratoconic patients were evaluated. Subjects were classified according to their preoperative corrected distance visual acuity (CDVA) into 5 different groups: grade I, CDVA of 0.90 or better; grade II, CDVA equal to or better than 0.60 and worse than 0.90; grade III, CDVA equal to or better than 0.40 and worse than 0.60; grade IV, CDVA equal to or better than 0.20 and worse than 0.40; and grade plus, CDVA worse than 0.20. Success and failure indices were defined based on visual, refractive, corneal topographic, and aberrometric data and evaluated in each group 6 months after ICRS implantation. RESULTS: Significant improvement after the procedure was observed regarding uncorrected distance visual acuity in all grades (P < .05). CDVA significantly decreased in grade I (P < .01) but significantly increased in all other grades (P < .05). A total of 37.9% of patients with preoperative CDVA 0.6 or better gained 1 or more lines of CDVA, whereas 82.8% of patients with preoperative CDVA 0.4 or worse gained 1 or more lines of CDVA (P < .01). Spherical equivalent and keratometry readings showed a significant reduction in all grades (P ≤ .02). Corneal higher-order aberrations did not change after the procedure (P ≥ .05). CONCLUSIONS: Based on preoperative visual impairment, ICRS implantation provides significantly better results in patients with a severe form of the disease. A notable loss of CDVA lines can be expected in patients with a milder form of keratoconus.

The Authors retrospectively evaluated the evolution of corneal astigmatism 6, 12 and 24 months after penetrating keratoplasty in 75 eyes by comparing 2 suture techniques: running suture (RS) in 14 cases vs interrupted suture (IS) in 61 cases. The mean keratometric astigmatism in patients with RS was 7.75 +/- 3.10 D at 6 months, 5.89 +/- 2.50 D at 12 months and 3.90 +/- 1.70 D at 24 months. In patients with IS these values were 4.82 +/- 4.00 D at 6 months, 2.81 +/- 1.60 D at 12 months and 2.77 +/- 1.34 D at 24 months. A significant lower astigmatism (P0.05) was noted after using IS at 6 and 12 months. At 24 months, however, this difference was no longer statistically significant (P0.3). The IS suture allowed a better control of the post-surgical astigmatism, and a more rapid recovery of the visual acuity.

Purpose: To develop 27 short sentence optotypes for the Portuguese version of the Radner Reading Charts. Methods: Thirty-four Portuguese sentences were constructed following the concept of the Radner Reading Charts to obtain highly comparable sentences in terms of lexical difficulty, syntactical complexity, word length, number of syllables, and position of words. A long text (106 words) at the 5th grade reading level was also tested to assess the validity of the reading speeds obtained with the short sentences. The short sentences and long text were tested in 50 volunteers with similar educational backgrounds (mean age 30.98 years ± 6.99 years, range 19-47 years). Reading speeds were measured with a stop-watch and reported as words per minute (wpm). The reading time for each of the short sentences to be selected for the chart was defined as falling within the range of the mean ± 0.40 × standard deviation (SD). Results: The overall mean reading speed for each of the short sentences was 235.43 ± 36.39 wpm. The 27 sentences with a mean between 220.8 and 250.0 wpm (overall mean ± 0.40 × SD) were selected for construction of the reading charts. The mean reading speed for the long text was 212.42 ± 26.20 wpm. Correlation between the selected short sentences and long text was high (r =0.86). Reliability analysis yielded an overall Cronbach's alpha coefficient of 0.97. Conclusions: The 27 short Portuguese sentences were highly comparable in terms of syntactical structure, number, position and length of words, lexical difficulty, and reading length. This reading test can overcome the limitations of the current tests for homogeneity and comparability, reducing subjectivity in the evaluation of the functional outcomes of medical and surgical ophthalmologic treatments. RESUMO Objetivo: Desenvolver 27 frases-optotipo para a versão em português das tabelas de leitura de Radner. Métodos: Trinta e quatro frases em português foram elaboradas de acordo com o conceito das tabelas de leitura de Radner, de forma a obter frases-optotipo, altamente comparáveis em termos dificuldade lexical, complexidade sintática, tamanho das palavras, número de sílabas e posição das palavras. Foi também avaliado um texto longo (106 palavras) ao nível do 5o ano de escolaridade para determinar a validade dos resultados obtidos com as frases curtas. As frases curtas e o texto longo foram testados em 50 voluntários de nível acadêmico semelhante e média de idades de 30,98 anos ± 6,99 (intervalo de 19-47 anos). A velociade de leitura foi medida com cronômetro, de forma a obter o número de palavras por minuto (wpm). O intervalo válido para tempo de leitura das frases curtas foi definido como a média ± 0,40 x desvio padrão (SD). As frases mais semellhantes foram estatisticamente selecionadas para a construção das tabelas de leitura Radner-Coimbra. Resultados: A velocidade média de leitura obtida com as frases curtas foi 235,43 ± 36,39 wpm. As frases com velocidade média entre 220,8 e 250,0 palavras por minuto (média ± 0,40 x SD) foram selecionadas. Vinte e sete frases cumpriram este critério. A velocidade média de leitura do texto longo foi 212,42 ± 26,20 wpm. A correlação entre as frases curtas selecionadas e o texto longo foi alta (r=0,86). A análise de fiabilidade originou um coeficiente alfa de Cronbach de 0,97. Conclusões: As 27 frases em português são altamente semelhantes em termos de estrutura sintática, número, posição e comprimento das palavras, dificuldade lexical e duração da leitura. Este teste permite ultrapassar as limitações dos testes existentes em termos de homogeneidade e comparabilidade, reduzindo a subjetividade na avaliação dos resultados de terapêuticas médicas e cirúrgicas.

Photorefractive keratectomy (PRK) was performed on 98 consecutive normal myopic eyes with the Summit OmniMed laser System. The minimum follow-up was 3 months and 31 were followed for 6 months. Preoperative myopia ranged from -1.25 to -12.00 D. The myopic eyes were divided into 4 groups according to the amount of myopia: group 1 (-1.25 to -3.00 D), 17 eyes; group 2 (-3.12 to -6.00 D), 42 eyes; group 3 (-6.12 to -9.00 D), 29 eyes and group 4 (>9.00 D), 10 eyes. In group 1 mean uncorrected visual acuity was 0.87 at 3 months, 1.0 at 6 months and all of the eyes were within 0.50 D of the attempted correction. In group 2 mean uncorrected visual acuity was 0.76 at 3 months, 0.87 at 6 months and 92.3% of the eyes were within 0.50 D of the attempted correction. In group 3 mean uncorrected visual acuity was 0.65 and 0.66 at 3 and 6 months respectively and 77.8% of eyes were within 0.50 D of the attempted refractive correction. In group 4, mean uncorrected visual acuity was 0.46 and 0.7 at 3 and 6 months, respectively, and 100% were within 0.50 D of the attempted correction. Two eyes lost 2 lines and 4 eyes gained 2 or more lines of their preoperative best spectacle corrected visual acuity. Three eyes exhibited steroid induced rise in intraocular pressure that was controlled with topical timolol. No serious complications occurred. Despite the short follow-up, photorefractive keratectomy with the 193 nm excimer laser appears to be an effective and safe treatment for the correction of myopia. [J Refract Corneal Surg. 1994;10:S231S235.1