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Marios P Giannakopoulos,1 Anna G Antonacopoulou,2 Anastasia E Kottorou,2 Haralabos P Kalofonos,2 Sotirios P Gartaganis1 1Department of Ophthalmology, School of Medicine, 2Department of Medicine, Molecular Oncology Laboratory, Division of Oncology, University of Patras, Rion, Greece Purpose: In this study we aimed to evaluate the polymorphism at codon 129 (M129V) of the PRNP gene as a secondary risk factor for pseudoexfoliation syndrome (PEX). Methods: Two hundred and seventy-five unrelated subjects, including 156 patients with PEX and 119 unrelated control subjects, were recruited from the University Hospital of Patras, Greece. All patients and controls were of Caucasian or European ancestry. The PRNP M129V (A/G) single-nucleotide polymorphism was genotyped by real-time polymerase chain reactions. Association of the polymorphism with PEX was assessed using the two-sided Pearson’s chi-squared or Fisher’s exact test.Result: No significant difference between patients and controls was observed in terms of frequencies of alleles and genotypes of the PRNP gene.Conclusion: Polymorphism at M129V of the PRNP gene was evaluated as a secondary risk factor for developing PEX. Our results suggest that this PRNP gene polymorphism is not associated with PEX. Keywords: pseudoexfoliation syndrome, polymorphism, M129V, PEX, protein folding disorders

Alexios A Panoutsopoulos,1 Vassiliki S Gartaganis,2 Marios P Giannakopoulos,1 Panos D Goumas,3 Evangelos D Anastassiou,4 Sotirios P Gartaganis1 1Department of Ophthalmology, School of Medicine, University of Patras, Achaia, Greece; 2Protein Chemistry Group, Institute of Molecular Oncology, BSRC “Al Fleming”, Vari, Greece; 3Department of Otolaryngology, Head and Neck Surgery, 4Department of Microbiology, School of Medicine, University of Patras, Achaia, Greece Purpose: The aim of this study was to determine the possible association of rs1048661 and rs3825942 single nucleotide polymorphisms (SNPs) in the lysyl oxidase-like 1 (LOXL1) gene of cataract patients from southwestern Greece with pseudoexfoliation (PEX) syndrome. Patients and methods: Ninety-three patients with PEX syndrome and 74 without PEX syndrome were recruited with the principal diagnosis being cataract. LOXL1 SNPs, rs1048661 and rs3825942, were genotyped by using polymerase chain reaction. Results: The G allele of rs1048661 was found in 96.7% in the PEX group as compared to 80.5% of non-PEX alleles (P=19×10-4; Odds ratio [OR] =5.37; 95% confidence interval [CI] =1.68–17.12). Similarly, the G allele of rs3825942 was found in 72.1% of the PEX group as compared to 41.8% of non-PEX alleles (P=4×10-5; OR =3.78; 95% CI =1.98–7.23). The T and A allele frequencies of rs1048661 and rs3825942, respectively, were underrepresented in the PEX group patients as compared to non-PEX group. Conclusion: Our data confirm previously reported association between LOXL1 polymorphisms and PEX syndrome in a southwestern Greek population. A significant association was found for the G allele of rs1048661 and rs3825942 demonstrating that the GG haplotype is a high-risk factor for the development of PEX syndrome. Keywords: exfoliative syndrome, PEX syndrome, single nucleotide polymorphisms

We investigated the time-dependent ocular surface bacterial colonisation of sedated patients hospitalised in an intensive care unit and aimed to evaluate whether proper topical antibiotic prophylaxis could prohibit corneal infection. The study lasted 12 months and included 134 patients undergoing sedation and mechanical respiratory support for various medical reasons. Patients hospitalised for less than seven days and those with pre-existing ocular surface pathology were excluded. All patients were examined on admission by inspecting the cornea for erosions. Followup examinations were performed each subsequent day. Cultures were also obtained from the conjunctival sac of both eyes on admission and every seventh day until the end of sedation. Standard laboratory techniques were used for isolation, identification and antibiotic susceptibility testing of bacteria. Antibiotic treatment for prophylaxis was administered accordingly. Analysis was carried out for 70 patients. Duration of sedation ranged from seven to 122 days. Fifty-four (77%) patients were colonised by at least one bacterial species other than normal flora within seven to 42 days. Multiple bacteria were isolated from 28 patients undergoing prolonged sedation. Prevalent isolates were Pseudomonas aeruginosa, Acinetobacter spp. and Staphylococcus epidermidis. Infectious keratitis was prohibited in all cases. Ocular surface of long-term sedated patients was found to be colonised by various bacterial species and their isolation was closely associated with the time period of hospitalisation. The results of this study suggest that the early identification of ocular surface bacteria colonisation and the administration of topical antibiotics for prophylaxis can prohibit corneal infection in these patients. [ABSTRACT FROM AUTHOR]

We report an unusual, rare case of opacification of the hydrophilic acrylic intraocular lens (IOL) 23 years after the initial surgery with significant visual deterioration. Opacification of the hydrophilic acrylic IOL was primarily due to the formation of folds on the surface of the lens material, and less so due to calcium phosphate deposits. Calcification opacification can be attributed to recent events, as evidenced by deposits of dicalcium phosphate dihydrate (CaHPO 4 2H 2 O) and octacalcium phosphate (Ca 8 H 2 (PO 4 ) 6 5H 2 O), both of which are transient calcium phosphate phases, converting hydrolytically to the thermodynamically most stable hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 ). To our knowledge, this case of hydrophilic acrylic IOL opacification is the only one that has been described so late, 23 years after cataract surgery., Competing Interests: The authors declare that there is no conflict of interest., (© The Author(s) 2024.)

Background: Hydrophilic intraocular lens opacification is a rare complication due to calcification. With current new surgical techniques, including lamellar endothelial keratoplasty and vitrectomies, this irreversible complication is becoming more common. In this case study, we present clinical and laboratory features of a case of Carlevale hydrophilic acrylic IOL calcification., Case Presentation: Observational case report of a single incident case. An 83-year-old man was referred to our ophthalmic department complaining of right eye vision blurring for six months. Slit-lamp biomicroscopy revealed IOL opacification. Deposits of calcium phosphate were found both on the IOL's surface and inside it, according to thorough investigation using optical, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectrometry., Conclusions: To the best of our knowledge, this is the first case to describe the laboratory evidence of Carlevale hydrophilic IOL calcification, suggesting possible explanation mechanisms based on underlying pathology and surgical technique. It reminds us that these findings suggest that physicians should be aware of possible hydrophilic IOL calcification., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Purpose: To evaluate the effectiveness of intravitreal ranibizumab in combination with laser photocoagulation in the management of Coats disease., Method: Six intravitreal injections of 0.5 mg (0.05 mL) ranibizumab were performed, each 4 weeks apart. Correspondence to therapy was evaluated using visual acuity measurements and optical coherence tomography images. Six months after the initiation of treatment, laser photocoagulation was applied on the telangiectasias and on the surrounding ischemic areas, followed by a single intravitreal ranibizumab injection. Three months later, laser photocoagulation was repeated in purpose to prevent recurrence., Results: In the sixth month, no improvement in visual acuity was recorded, as thick circinate hard exudates still remained in the submacular space. Nevertheless, retinal detachment had completely subsided, and fluorescein angiography showed a significant decrease of leakage from the telangiectatic vessels. At the 12-month follow-up visit, an impressive improvement was recorded, with total absorption of the submacular exudate and visual acuity being 20/30. At the 20-month follow-up visit, his visual acuity was 20/20 and the retina was flat with no signs of macular edema or exudates. At the 6-year follow-up visit, the patient was absolutely stable., Discussion: Elevated vascular endothelial growth factor levels have been demonstrated in Coats disease. Anti-vascular endothelial growth factor agents assist to the decrease of vascular permeability of the capillary endothelial cells, thus increasing the efficiency of laser application.

Purposes: To (i) determine expression patterns of lysyl oxidase-like 1 (LOXL1), fibrillin-1 (FBN1), transforming growth factor beta-1 (TGF-β1), and cyclooxygenase-2 (COX-2) in lens epithelium and anterior lens capsule in pseudoexfoliation (PEX) syndrome and (ii) delineate the roles of these proteins in the etiopathogenesis of PEX., Materials and Methods: Study participants, all of whom had undergone cataract surgery, comprised 47 patients with and 27 patients without (controls) PEX syndrome. Immunohistochemistry on paraffin sections of lens capsule and lens epithelium was performed., Results: Immunoexpression of LOXL1 and FBN1 on the outer surface of the lens capsule was significantly higher (p < 0.001), and nuclear immunopositivity for LOXL1 was more frequently observed (p = 0.017), in PEX patients compared with control patients. Cytoplasmic expression of LOXL1 and COX-2 was significantly lower (p = 0.015 and p = 0.042, respectively) in PEX patients compared with controls. TGF-β1 exhibited diffuse immunostaining detected in all cell layers in PEX patients (p <0.001). Significant direct correlations of cytoplasmic LOXL1 with FBN1 and TGF-β1, and of COX-2 with FBN1, TGF-β1, and LOXL-1, were observed only in PEX patients., Conclusions: Results of our study provide valuable information vis-à-vis expression and localization of TGF-β1, LOXL1, and FBN1, as well as their associations in the lens epithelium and lens capsule. These data not only advance our knowledge of the etiopathogenesis of PEX syndrome, but also include novel findings, for example, immunostaining patterns of TGF-β1 in PEX syndrome. We suggest that COX-2 plays a role in the pathobiology of PEX syndrome and should be the subject of future investigations.

Purpose: To investigate the nature and characteristic features of deposits causing opacification of intraocular lenses (IOLs) based on the examination of clinical findings using scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDX) analysis., Design: Retrospective, observational case series., Methods: This is a multicenter study of 6 hydrophilic acrylic IOLs (Lentis LS-502-1; Oculentis GmbH, Berlin, Germany) with a hydrophobic surface that were explanted from 5 patients because of opacification. Three patients had an uncomplicated phacoemulsification. One patient underwent combined phacoemulsification and pars plana vitrectomy for retinal detachment and later silicone oil endotamponade owing to redetachment. The last patient had a pars plana vitrectomy and silicone oil instillation combined with phacoemulsification for tractive retinal detachment and diabetic retinopathy. The explanted lenses were submitted to our laboratory and were examined by SEM and EDX in order to identify the morphologic features and the composition of the deposits., Results: SEM and EDX analyses confirmed the presence of calcific deposits in the interior of the opacified hydrophilic IOLs, with a pattern showing the formation of lumps on the surface. The lumps were due to subsurface formation of calcium phosphate crystalline deposits. The crystallite clusters seemed to diffuse from the IOL interior to the surface., Conclusions: We demonstrated the calcification pattern of the hydrophilic IOL (Lentis LS-502-1) with a hydrophobic surface. Although hydrophilic acrylic lenses have a hydrophobic surface, the development of calcification is a possible threat initiating from the hydrophilic subsurface of the IOLs., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objectives: To investigate the incidence of fungal contamination of store disinfectant solutions contained in contact lens storage cases belonging to asymptomatic contact lens users., Methods: Asymptomatic contact lens users were asked to bring their storage cases, lenses included, without having opened the lid of the cup after placing lenses inside. The following information was recorded: age, sex, type of refractive error, contact lens material, schedule of wear, and brand of disinfectant solution. Included subjects had to comply with lens handling, cleaning, and replacement instructions given by the manufacturer or their attending optometrist. One sample per cup of contact lens case was collected using a sterile syringe. Samples were cultured on proper media for 96 hr at 35°C. Fungi were identified to species level by standard methodology., Results: A total of 216 samples were collected from 117 contact lens storage cases. All participants were using monthly disposable hydrogel lenses on a daily wear basis. Seven fungal species were isolated from 15 specimens (6.9%) collected from 12 storage cases (10.2%). These included one Fusarium solani, four Aspergillus niger, two Aspergillus fumigatus, five Candida parapsilosis, one Candida tropicalis, one Rhodotorula rubra, and one F. solani in combination with Candida guilliermondii. Disinfectant solutions containing hydrogen peroxide were found to be less effective than various alternative solutions in eliminating fungal species., Conclusions: The results of this study show that even when contact lens users report compliance for handling, cleaning, and replacement according to the manufacturer's instructions, the potential risk of contact lens-related fungal keratitis still remains.

Pseudoexfoliation (PEX) syndrome is a well-recognized late-onset disease caused by a generalized fibrillopathy. It is linked to a broad spectrum of ocular complications including glaucoma and perioperative problems during cataract surgery. Apart from the long-known intraocular manifestations, PEX deposits have been found in a variety of extraocular locations and they appear to represent a systemic process associated with increased cardiovascular and cerebrovascular morbidity. However, as published results are inconsistent, the clinical significance of the extraocular PEX deposits remains controversial. Identification of PEX deposits in the heart and the vessel wall, epidemiologic studies, as well as, similarities in pathogenetic mechanisms have led to the hypothesis of a possible relation between fibrillar material and cardiovascular disease. Recent studies suggest that PEX syndrome is frequently linked to impaired heart and blood vessels function. Systemic and ocular blood flow changes, altered parasympathetic vascular control and baroreflex sensitivity, increased vascular resistance and decreased blood flow velocity, arterial endothelial dysfunction, high levels of plasma homocysteine and arterial hypertension have all been demonstrated in PEX subjects. Common features in the pathogenesis of both atherosclerosis and PEX, like oxidative stress and inflammation and a possible higher frequency of abdominal aorta aneurysm in PEX patients, could imply that these grey-white deposits and cardiovascular disorders are related or reflect different manifestations of the same process.

Purpose: To report a case of an unusually large cavernous hemangioma of the optic disk., Method: Case report with funduscopic, fluorescein angiography, and magnetic resonance imaging correlations. A 20-year-old woman with no ocular or systemic history was diagnosed with cavernous hemangioma of the optic disk in a routine eye examination., Results: Fundus examination revealed an extremely large cavernous hemangioma of the optic disk, almost 4.5 disk diameter. Fluorescein angiography showed delayed filling of the lesion with intravascular plasma-erythrocyte separation and no leakage. No systemic involvement was found., Conclusion: This case represents an atypical presentation of cavernous hemangioma of the optic disk, among the largest reported in the literature. After a 5-year follow up period, no change has been documented.

Purpose: Parstatin is a 41-mer peptide formed by proteolytic cleavage on activation of the PAR1 receptor. The authors recently showed that parstatin is a potent inhibitor of angiogenesis. The purpose of the present study was to evaluate the therapeutic effect of parstatin on ocular neovascularization., Methods: Choroidal neovascularization was generated in mice using laser-induced rupture of Bruch's membrane and was assessed after 14 days after perfusion of FITC-dextran. Oxygen-induced retinal neovascularization was established in neonatal mice by exposing them to 75% O(2) at postnatal day (P)7 for 5 days and then placing them in room air for 5 days. Evaluation was performed on P17 after staining with anti-mouse PECAM-1. The effect of parstatin was tested after intravitreal administration. The effects of subconjunctival-injected parstatin on corneal neovascularization and inflammation in rats were assessed 7 days after chemical burn-induced corneal neovascularization. Retinal leukostasis in mice was assessed after perfusion with FITC-conjugated concanavalin A., Results: Parstatin potently inhibited choroidal neovascularization with an IC(50) of approximately 3 μg and a maximum inhibition of 59% at 10 μg. Parstatin suppressed retinal neovascularization with maximum inhibition of 60% at 3 μg. Ten-microgram and 30-μg doses appeared to be toxic to the neonatal retina. Subconjunctival parstatin inhibited corneal neovascularization, with 200 μg the most effective dose (59% inhibition). In addition, parstatin significantly inhibited corneal inflammation and VEGF-induced retinal leukostasis. In all models tested, scrambled parstatin was without any significant effect., Conclusions: Parstatin is a potent antiangiogenic agent of ocular neovascularization and may have clinical potential in the treatment of angiogenesis-related ocular disorders.

Purpose: To develop scleral controlled-release-systems of triamcinolone acetonide (TA) based on biodegradable poly(lactide) (PLA)., Materials and Methods: (1) PLA microspheres containing TA were prepared by a single or double emulsification-solvent evaporation method. Morphology, size, effect of drug input and method of microsphere preparation on drug loading, and in vitro TA release of the microspheres were investigated. (2) Mini-tablets consisting of blank PLA-microspheres and TA (weight ratios of 1:1, 2:1, and 4:1, respectively) were developed and their release profile in vitro was evaluated. (3) The in vitro transscleral diffusion profile was evaluated by placing a PLA-TA (1:1) tablet in a donor chamber and measuring the TA concentration in a receptor chamber. Donor and receptor chambers were separated by rabbit sclera. (4) Two cadaver rabbit eyes received a 1:1 PLA-TA tablet episclerally, which was covered by a scleral patch. TA aqueous humor and vitreous concentrations were measured 5, 10, and 20 days post implantation., Results: (1) Microsphere average size was 2 μm. The double emulsification method and increasing drug input led to an increase in drug loading and encapsulation. Sustained release of TA over several days from the microspheres in vitro was observed, with the rate of release being affected by their TA content. (2) TA exhibited sustained release profile from the PLA-TA tablets, with the rate of release being affected by the PLA:TA ratio. (3) TA could slowly cross the sclera tissue in vitro, with approximately 21% of the drug loaded in the donor compartment being diffused through the sclera in 45 days. (4) Following scleral administration of the PLA-TA mini-tablets, TA accumulated in the vitreous and aqueous humor of cadaver eyes., Conclusions: The PLA-TA microspheres and mini-tablets appear promising for the controlled transscleral delivery of TA and justify further investigation.

Background: To investigate the relationship between exfoliation syndrome and sensorineural hearing loss., Methods: A prospective study was designed. Patients with evidence of ocular exfoliation syndrome (study group) and individuals without any clinical signs of exfoliation syndrome (control group) were selected. Cases and controls were chosen to have similar demographic characteristics. Study and control group subjects with a history of conditions affecting hearing function were excluded. Pure-tone audiometry was performed in all participants in both groups and hearing thresholds were measured at frequencies of 0.25, 0.5, 1, 2, 4 and 8 kHz (kilohertz) for each ear., Results: A total of 69 subjects participated in the study. The study group included 47 subjects and the control group 22. There was no significant difference in mean age (P = 0.985) and gender (P = 0.378) between groups. Mean pure-tone hearing thresholds were significantly higher in study group at frequencies of 4 kHz (P = 0.004) and 8 kHz (P = 0.001), but not at frequencies of 0.25, 0.5, 1 and 2 kHz. The greatest difference in the comparison of mean hearing thresholds between study and control group was noted at 8 kHz., Conclusions: The above results are in accordance with previous studies and provide additional evidence of the association between exfoliation syndrome and sensorineural hearing loss at high frequencies. Particular effect was shown on the highest frequency of 8 kHz. These findings may support the systemic nature of exfoliation syndrome.

Anodic stripping voltammetric (ASV) procedure, using mercury film electrode, was optimized and applied to determine the concentrations of zinc, cadmium, and copper in the aqueous humor. Concentration levels as low as 1 ppb of the test metals was possible to be detected using short electrolysis times (120 s) and microquantities of aqueous humor (up to 35 μL). As a first application of the voltammetric analysis of trace metals in the aqueous humor, the role of the three selected trace elements in the pseudoexfoliation (PEX) syndrome was examined. Samples from aqueous humor were collected during cataract extraction from patients with and without PEX. The zinc and copper concentration levels in the aqueous humor did not show statistically significant difference in the study and control group. Cadmium was detected in a small number of samples, without however statistical differences between the two groups. ASV proved to be a highly precise and sensitive tool for the quantification of heavy metal ions in aqueous humor. Further studies may lead to useful conclusions for the role of zinc, copper, or cadmium in PEX syndrome.

Purpose: To investigate the prevalence of glaucoma and coronary artery disease (CAD) in patients with cataract and pseudoexfoliation (PEX) syndrome., Methods: Cross-sectional study of 2140 consecutive patients with cataract admitted at the University Hospital of Patras, Greece, for cataract surgery. Only patients with senile cataract were included in this study. All patients underwent a complete ophthalmological examination that included slit-lamp evaluation with dilated pupil for PEX material in the anterior segment, intraocular pressure (IOP) measurements, and optic disc cup examination. They also underwent an evaluation for CAD by a cardiologist. CAD was considered present if a patient had a history of myocardial infarction, or ischaemia, or abnormal coronary angiography. The patients were classified into two groups: the PEX and the non-PEX group., Results: One thousand and eighty-eight (50.8%) patients were men and 1052 (49.2%) were women. The overall prevalence of PEX syndrome was found to be 27.9% and it was found to increase with progressing age. Bilateral PEX was more frequent than unilateral PEX, with the percentage of bilateral PEX raising with progressing age. A total of 132 patients (22.1%) in the PEX group exhibited glaucoma, while in the non-PEX group only 2.5% suffered glaucoma. PEX was also found to be positively associated with the risk for CAD among subjects 50 years or older. No association between CAD and glaucoma was found., Conclusions: PEX syndrome constitutes a major glaucoma risk factor and a CAD risk factor. Patients with PEX should be informed and examined frequently as the risk is present throughout.

Purpose: To identify the nature and to investigate the biochemical mechanisms leading to late opacification of implanted hydrophilic acrylic intraocular lenses (IOLs)., Design: Retrospective laboratory investigation., Methods: setting: Department of Ophthalmology, Medical School, Department of Chemical Engineering, Laboratory of Inorganic and Analytical Chemistry, University of Patras and FORTH-ICEHT, Greece. study population: Thirty IOLs were explanted one to 12 years postimplantation attributable to gradual opacification of the lens material. observation procedures: Materials analysis was done using scanning electron microscopy (SEM) equipped with a microanalysis probe (EDS), confocal microscopy, x-ray diffraction (XRD), and Fourier transform infrared (FTIR) for the identification of the substances involved in the opacified lenses., Results: SEM investigation showed plate-like as well as prismatic nanoparticle deposits of calcium phosphate crystallites on the surface and in the interior of opacified IOLs. The plate-like deposits exhibited morphology and particle size typical for octacalcium phosphate (OCP), while the respective characteristics of the prismatic nanocrystals were typical of hydroxyapatite (HAP). EDS analysis confirmed the chemical composition of the deposits. Aqueous humor analysis showed that the humor is supersaturated with respect to both OCP and HAP, favoring the formation of the thermodynamically more stable HAP, while the formation and kinetic stabilization of other transient phases is also very likely. In vitro experiments using polyacrylic materials confirmed the clinical findings., Conclusions: Hydrophilic acrylic IOLs' opacification may be attributed to the deposition of calcium phosphate crystallites. HAP is the predominant crystalline phase of these crystallites. Surface hydroxyl groups of the polyacrylic materials facilitate surface nucleation and growth.

Purpose: To report an extremely rare case of an extensive conjunctival-corneal invasive squamous cell carcinoma., Methods: A healthy 68-year-old man referred to our department with a moderately elevated hyperemic nodular mass on his right ocular surface. The lesion was completely covering the corneal surface and involved the temporal limbus with bulbar conjunctiva. Surgical excision was performed with 2-mm tumor-free margins documented histologically and double-freeze cryotherapy was applied 360 degrees for inhibition of tumor recurrence., Results: Histopathologic examination showed a moderately differentiated squamous cell carcinoma. The patient achieved a complete excision with no evidence of recurrence during the follow-up period of 12 months., Conclusions: This case points out the potential for a total covering of the cornea by squamous cell carcinoma. Wide surgical excision and double freeze-thaw cryotherapy may decrease the recurrence.

A variety of syndromes leading to hemosiderosis in men cause ocular lesions. The purpose of the present study was to determine the distribution of iron and of transferrin in the eyes and lacrimal glands of rats in experimental hemosiderosis, so as to achieve a better understanding of the formation of the ocular lesions observed in patients with advanced hemosiderosis. In order to achieve hemosiderosis the rats were fed 3% (w/w) carbonyl iron or received i.p. or i.v. polymaltose iron. Hemosiderin deposits were detected in macrophages lying in the interlobular connective tissue of lacrimal glands, in the interstitial connective tissue of the choroid, in the ciliary body, in the iris and extracellularly in the sclera in all animals that received iron i.v. Also, scanty hemosiderin laden macrophages were found to a lesser degree in interstitial connective tissue of the choroid and in the interlobular connective tissue of lacrimal glands in animals that received iron i.p. No iron deposits were detected in the eye and lacrimal glands of control rats and in rats that were on an iron enriched diet. No transferrin was detected in the eye and in the lacrimal glands, neither in the control rats nor in the rats that received iron. Experimental iron overload leads to increased iron deposition in tissues of the eye and lacrimal glands, whereas no transferrin could be detected in the aforementioned organs.

Purpose: To investigate the oxidative status in lens epithelial cells of patients with pseudoexfoliation (PEX) syndrome., Methods: Lens capsule samples obtained during cataract surgery of patients with PEX syndrome and normal age-matched control subjects were examined for changes in the levels of glutathione (GSH), glutathione disulphide (GSSG), protein concentration, and lipid peroxidation. Concentrations of GSH, GSSG, lipid peroxidation, and protein concentration were determined by specific fluorescent assays., Results: This study shows a 2.2- and 2.0-fold decrease in GSH and GSSG levels, respectively, in PEX lens epithelial lens compared with non-PEX lens epithelial cells, as well as a 2.5-fold increase in lipid peroxidation product malondialdehyde (MDA) levels., Conclusion: The increased MDA and decreased GSH levels indicate high oxidative stress. On the other hand, GSSG usually increases in cases of high-oxidative stress, but this is not always the case, as it may not always accumulate in cells. Our findings suggest a role for oxidative stress in the pathogenesis and the progression of PEX syndrome.

Background: Several rheological disorders of the erythrocytes, such as increased aggregation and decreased deformability, have been observed in diabetes mellitus and have been implicated in the development of diabetic microangiopathy. Structural alterations of the erythrocyte membrane proteins caused by the diabetic process may be at the origin of those observations. In the present study, we searched for erythrocyte membrane protein alterations in diabetic retinopathy., Methods: We examined peripheral blood samples from 40 type-2 diabetic patients with diabetic retinopathy of variable severity (19 males and 21 females, mean age 66.8 years, Group A) and we compared them with samples from 19 type-2 diabetic patients without diabetic retinopathy (13 males and six females, mean age 66.5 years, Group B) and 16 healthy volunteers (eight males and eight females, mean age 65.6 years, Group C). Erythrocyte membrane ghosts from all samples were subjected to SDS-PAGE, and the electrophoretic pattern of transmembrane and cytoskeletal proteins was analysed for each sample. The protein quantification of each electrophoretic band was accomplished through scanning densitometry., Results: No significant deviations from normal electrophoresis were observed in Groups B and C, apart from an increase in band 8 in two samples from Group B (11%). In contrast, in 14 samples from Group A (35%) we detected increases in protein band 8 and/or membrane-bound haemoglobin along with a decrease in spectrin. Moreover, increased mobility of band 3, an aberrant high molecular weight (MW) (> 255 kDa) band and a low MW (42 kDa) band were evident in ten samples from Group A (25%). Glycophorins were altered in 46% of Group-A patients versus 38% of Group-B patients. Females and patients with long duration of diabetes presented more electrophoretic abnormalities., Conclusions: Structural alterations of the erythrocyte membrane proteins are shown for the first time in association with diabetic retinopathy. Their detection may serve as a blood marker for the development of diabetic microangiopathy. Further studies are needed to assess whether pharmaceutical intervention to the rheology of erythrocytes can prevent or alleviate microvascular diabetic complications.

The effect of systemic steroid administration on intraocular pressure (IOP) is well established. However less attention has been paid to the effect of steroids when administered in a nasal spray. We conducted a study to investigate a possible association between nasal steroids and elevated IOP in 54 patients who were being treated for allergic rhinitis. IOP was measured before the patients started therapy and thereafter every 5 days during that therapy. Follow-up ranged from 27 to 35 days (mean: 31). Statistical analysis revealed no significant elevation in IOP after nasal steroid administration. It seems that short-term administration of nasal steroids does not cause significant IOP elevation. Nevertheless, their long-term effects on this pressure should be investigated.

Purpose: To present an atypical case of acanthamoeba keratitis in a soft contact lens wearer., Methods: A case report of a 28-year-old female soft contact lens wearer with a 6-day history of redness and blurred vision in her right eye. Examination showed stromal keratitis that did not respond to therapy for herpes simplex virus. Four weeks later, the patient had increased stromal infiltration, an endothelial plaque, and a hypopyon. She did not complain of pain apart from mild discomfort. Corneal smears and anterior chamber tap were negative for bacteria, fungi, acanthamoeba, and herpes simplex virus, and the patient was prescribed fortified antibiotics. One week later, a large epithelial defect with a surrounding ring infiltrate was apparent. Corneal biopsy showed acanthamoeba., Results: The acanthamoeba keratitis resolved with successful treatment. One year later, the patient had a residual visual deficit secondary to stromal scarring and her best-corrected visual acuity was 20/29., Conclusions: This case emphasizes the importance of considering acanthamoeba species in the differential diagnosis of keratitis, even without the classic symptom of severe pain. A high degree of suspicion with rapid and appropriate treatment may result in improved recovery of vision.

Purpose: Staphylococcus epidermidis is a leading cause of bacterial keratitis associated with corneal damage. Corneal integrity is closely associated with matrix macromolecules, such as proteoglycans (PGs) and collagen. The aim of this study was to examine whether active immunization (AI) using a major immunogenic polysaccharide determinant of slime (20-kDa PS) as antigen, and passive immunization (PI) after administration of specific antibodies toward 20-kDa PS affect the distribution of PGs as well as corneal lesions in an experimental model of slime-producing S. epidermidis keratitis., Methods: For AI, seven rabbits were immunized with 20-kDa PS, whereas for PI, seven rabbits received specific antibodies against 20-kDa PS. Lesions were graded clinically for a 21-day period. Levels of 20-kDa PS antibodies in serum and aqueous humor in both immunization groups were determined by ELISA. The distribution of certain extracellular matrix PGs during corneal healing was analyzed immunohistochemically., Results: Levels of specific anti-20-kDa PS antibodies in serum and aqueous humor obtained after either AI or PI were significantly higher as compared with those in the respective nonimmunized control groups (p<0.001). Clinical grading showed that both AI and PI rabbits had a significantly less corneal damage as compared with infected nontreated rabbits. Immunohistochemical analyses for PGs exhibited significant differences to the wounded regions as compared with noninfected corneal tissue. Accumulation of keratan sulfate PGs and decorin was observed in the corneal stroma of infected rabbits and of heparan sulfate PGs around the new-formed vessels. This phenomenon was significantly reduced in immunized animals in accordance with macroscopically decreased corneal damage observed in these animals., Conclusions: Results of this study suggest a key role of 20-kDa PS and its antibodies as prophylactic and therapeutic agents in keratitis caused by slime-producing S. epidermidis.

Pseudoexfoliation syndrome (PEX) is an age-related condition, which may cause open-angle glaucoma and has increasing interest since it seems to affect additional human tissues, i.e., cardiovascular tissue, skin, and still lacks elucidated pathogenesis. Collagen type IX and HNK-1 epitope have been considered characteristic constituents of the aqueous humour of PEX patients, since their amounts were increased in PEX aqueous humour compared to normal eyes. Since it has been proposed that the initial manifestations of PEX syndrome occur in conjunctiva, the present study was undertaken to investigate the presence of the same antigens in tears of PEX patients and their possible use as the biochemical markers for early diagnosis. Tears of PEX patients and healthy individuals were subjected to western blotting analysis for various basement membrane components identified in aqueous humour. It was found that collagen type IX and HNK-1 epitope were present in tears, the amount of the former being increased 2.7 times compared to normal (P<0.05), surprisingly high as compared with total protein or lysozyme activity in tears, which were found to be increased in PEX patients about 25% with no statistical differences (P approximately 0.4). The results suggest the possible use of tears' collagen type IX for the diagnosis of PEX syndrome.

Purpose: To investigate the oxidative status of the aqueous humor of patients with pseudoexfoliation (PEX) syndrome., Methods: Aqueous humor samples obtained during cataract surgery of patients with PEX syndrome and normal age-matched control subjects were examined for changes in the levels of glutathione (GSH), glutathione disulfide (GSSG), and TBA reactive species (TBARS), products of lipid peroxidation. GSH, GSSG, and TBARS were determined by specific fluorescent assays., Results: Compared to normal controls, PEX syndrome aqueous humor samples showed a decrease of up to 28% of GSH concentration, and GSSG was increased up to 23%. The ratio of GSH/GSSG was 1.7-fold decreased in PEX syndrome samples. TBARS levels were increased by 100% in the PEX aqueous humor samples as compared to the controls., Conclusions: High levels of GSSG and TBARS indicate high oxidative stress, as well as the decrease in the ratio of GSH/GSSG. Our findings suggest a role for oxidation stress in the pathogenesis and the progression of PEX syndrome.

Purpose: To determine the annual hospitalization rate and risk factors of eye injuries requiring hospitalization in an area of Greece., Methods: Retrospective case analysis of 899 consecutive patients with ocular injury admitted at the Department of Ophthalmology, University Hospital at Patras Medical School, Greece, over a 9-year period., Results: The average annual rate of hospitalized ocular injuries was 71.0 eye injuries per 1000 admissions at the Department of Ophthalmology. The majority (80.2%) of patients were male. The average age was 35.0 years (range 6 months-98 years). Approximately half of all injuries occurred in persons younger than 29 years of age. Patients with Albanian ethnic background were at higher risk. The most common type of injury was closed-globe injury (49.5%) that affected more frequently the very young individuals (0-19 years) and persons older than 50 years of age. Open-globe injuries occurred most often in young adults, 20 to 39 years of age, and comprised over 35% of all eye injuries in this age group. Most injuries (32.8%) occurred at the workplace, most commonly during construction activities. Injuries at home approximated the work-related injuries (30.0%). A total of 398 (42.5%) eyes underwent surgical intervention on the eye globe, while 49 (12.3%) of them underwent multiple operations as part of their treatment. 18.2% of the eyes were blinded and 27.9% had significant visual acuity loss. An enucleation during the follow-up period was performed in 4 (1.0%) eyes., Conclusions: Trauma is an important cause of ocular morbidity in Greece. Risk factors include young age, male gender, Albanian ethnic background, and workplace. General safety precautions and behavior modification are indicated.

Purpose: To investigate alterations in the proteoglycan (PG) and glycosaminoglycan (GAG) content of the aqueous humour in patients with pseudoexfoliation syndrome (PEX)., Materials and Methods: Aqueous humor samples were obtained during cataract surgery from nineteen patients bearing PEX features and twenty-three age-matched normal controls. Protein and IgG were quantified densitometrically after their electrophoretic separation. Collagen type IX, 3-sulphoglucuronic acid (HNK-1 epitope), biglycan and heparan sulphate proteoglycans were detected in Western and dot blots by using specific monoclonal antibodies (MAbs). The immunochemical analysis was performed in native aqueous humour or after degradation of the glycosaminoglycans with chondroitinases., Results: Degradation of the samples with chondroitinases ABC, AC and B revealed that, in the aqueous humour from PEX eyes, collagen type IX and biglycan had a more dermatan sulphate than did normal eyes. In addition, more HNK-1 epitope was observed in PEX eyes, which after similar enzymatic treatment was found to be located mainly in dermatan sulphate sequences. 3-sulphoglucuronic acid was a constituent of the GAG chains of the collagen type IX. We found that the electrophoretic mobility of the bands of collagen type IX and HNK-1 epitope was exactly the same in the aqueous humour of normal and PEX samples; both migrated as four bands at 120, 113, 92.6 and 56 kDa. The PGs bearing heparan sulphate were found only in normal samples. Other PGs were not detected., Conclusions: Because no significant difference was observed in the concentration of albumin and IgG in PEX and normal samples, the blood-aqueous barrier was probably not significantly compromised in PEX patients with cataract but without open-angle glaucoma. The results support the hypothesis that the pathogenesis of PEX can be linked to disturbed metabolism of GAGs and PGs.

Purpose: Patients with beta-thalassemia (beta-tha) represent a group with lifelong transfusion-dependent anemias. This study aimed to describe the conjunctival changes and tear film parameters in these patients., Methods: A total of 52 patients (104 eyes) with beta-tha major and 22 normal control subjects (44 eyes) were studied during 1999 through 2000. Tear film break-up time (BUT), Schirmer test, rose Bengal staining, and cytologic evaluation of the conjunctival epithelium were performed in all subjects. The Papanicolaou and May-Grümwald-Giemsa staining procedures were performed on all smears. Patients and control subjects were compared for tear function parameters and conjunctival changes., Results: The BUT, Schirmer test, and rose Bengal staining values were significantly lower (P < 0.001) in beta-tha patients than in control subjects. Keratinized cells were observed in conjunctival samples in 41% of patients, with a decrease in the number of goblet cells per slide in 64% of patients. In 9% of beta-tha patients, there were a slightly greater number of inflammatory cells than in control eyes., Conclusion: Ocular surface disorder of these patients was characterized by goblet cell loss and conjunctival squamous metaplasia. Our findings were correlated positively with the variable age. Epithelial damage by toxic reaction and disorder of tear quality and quantity are implicated as important factors in the pathogenesis of the ocular surface disease in beta-tha patients.

Purpose: To determine the clinical microbiological characteristics of corneal ulcers in contact lens wearers., Methods: A retrospective study of 23 patients admitted to our department with contact lens-related corneal ulcers during a 43-month period. Detailed demographic data, the type of contact lens, duration of lens wear, and wearing schedule were derived from a self-administered questionnaire. The severity of the ulcer; cultures of corneal scrapings, storage solutions, and contact lenses; treatment; and final outcome were evaluated., Results: Of the 86 cases of ulcerative keratitis admitted during the study period, 23 (26.74%) were attributed to contact lens use. Most patients were young women from urban areas. All of them were using soft contact lenses for 3 days to 20 years. Five patients used daily-wear lenses as extended-wear lenses. Most ulcers (47.82%) were mild; 30.43% were moderate; and 21.47% were severe. Corneal scrapings for cultures were obtained in 15 of the cases and were positive in 10 (43.47%) of them, whereas in 33.33% of the culture-positive storage solutions and in 66.67% of the culture-positive contact lenses, corneal scrapings were negative. Pseudomonas aeruginosa was the most frequent isolated pathogen (60%). The final visual acuity was 20/40 or better in 60.87% of the cases., Conclusions: Contact lens use is an important risk factor for the development of ulcerative keratitis, with P. aeruginosa remaining the predominant pathogen. It seems important to culture contact lenses and contact lens storage solutions, in addition to the corneal scrapings, and the role of initial therapy for the corneal ulcers remains important.

Objective: To determine the epidemiological characteristics of severe eye injuries in childhood, in a mixed urban and rural Greek setting., Methods: Retrospective analysis of 95 cases (103 eyes) of eye injuries in children younger than 17 years of age admitted to the Department of Ophthalmology, University Hospital of Patras, Greece, during a five-year period. The data were analyzed with respect to age, sex, type, cause and mode of injury, method of management, duration of hospitalization and final visual deficit., Results: The average age was 9.8 years and males were involved in 80% of the cases. The most common type of eye injury was mechanical closed-globe injury (71.8%). Mechanical open-globe injuries were found in 21.3% of the eyes, while burns comprised 6.7% of the injuries. Most injuries were agent-related, with blows and falls being responsible most often. Multiple operations were part of the treatment in 11.6% of the eyes; 14.5% of the eyes were blinded and 15.5% had significant final visual acuity loss., Conclusions: These hospital-based data suggest that there is a need for health education of both parents and children, since some injuries in children could easily have been prevented.

Staphylococcus epidermidis is an important cause of bacterial keratitis. Certain S. epidermidis strains produce an extracellular slime layer rich in an acidic polysaccharide with a molecular size of 20 kDa (20-kDa PS). We have demonstrated that the level of 20-kDa PS-specific antibodies significantly rises after establishment of slime-producing S. epidermidis bacteraemia and, furthermore, that rabbit polyclonal antibodies to 20-kDa PS opsonize cells of slime-producing S. epidermidis to a great degree and promote their clearance by polymorphonuclear cells (Arch. Biochem. Biophys. 342 (1997) 389; J. Pharm. Biomed. Anal. 22 (2000) 1029). The purpose of this study was to examine the protective and therapeutic effects both of active immunization, using 20-kDa PS as antigen, and of passive administration of specific antibodies towards the 20-kDa PS in a rabbit keratitis model. For active immunization, 20 rabbits were subcutaneously immunized with 20-kDa PS, whereas for passive immunization specific polyclonal IgG antibodies against 20-kDa PS were administered to 20 rabbits 1 day before induction of infection. Clinical observations were made weekly for 1 month and levels of 20-kDa PS antibodies in serum and aqueous humor in both immunization groups were determined by an enzyme immunoassay. The levels of specific anti-20-kDa PS IgG in serum and aqueous humor following either active or passive immunization were significantly higher as compared with control groups (P<0.001). Although, actively immunized rabbits showed significantly less corneal damage than control animals, passively immunized ones were significantly better protected as compared with both control and those actively immunized. Obtained results suggest that 20-kDa PS plays crucial role in the pathogenesis of S. epidermidis keratitis and that both types of immunization significantly protect against corneal S. epidermidis pathology and damage.

The purpose of this study was to determine the expression of metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in the aqueous humour of patients with exfoliation syndrome (XFS). XFS and control samples were analysed for their MMP content by zymography and for their tissue inhibitors by ELISA. In XFS eyes, an increase for up to 60% in almost all MMPs was observed, as compared to the controls. MMP-2 and MMP-9 were found to predominate. TIMP-1 levels in XFS samples were slightly decreased, while TIMP-2 levels were similar to those of the controls. Our findings suggest that MMPs may be crucial in the progression of XFS, by degrading the abnormal fibrillar matrix components in the anterior segment tissues of XFS eyes. However, the increased levels of MMPs seem not to be able to overcome the overproduction and accumulation of the exfoliative material., (Copyright 2002 S. Karger AG, Basel)

The purpose of this prospective study was to investigate the ocular side effects of short-term therapy with oral acitretin (1 mg/kg/day) in 24 patients with severe and recalcitrant dermatoses. Apart from the routine ophthalmological examination, the following tests were performed: break-up time of tear film for the determination of its stability, Schirmer test for the assessment of lacrimal gland function, rose bengal staining for the detection of possible ocular surface damage and contrast sensitivity test for the evaluation of visual function. No statistically significant differences could be found between the pretreatment values of the assessed parameters and those obtained after 1 and 2 months of therapy. It seems reasonable, therefore, to suggest that ocular surface integrity and tear film and visual function are not affected by short-term oral acitretin administration., (Copyright 2002 S. Karger AG, Basel)

Purpose: To quantify the concentrations of basic fibroblast growth factor (bFGF) and hyaluronan (HA) in the aqueous humor of patients with the exfoliation syndrome (XFS) or exfoliative glaucoma (XFG)., Methods: Aqueous humor bFGF and HA levels were measured in 13 patients with XFS and in 7 patients with XFG. The results were compared with those obtained from 17 healthy controls., Results: Mean bFGF levels were significantly higher in the XFG patients than those in the XFS patients, which in turn were higher than the bFGF levels in the healthy individuals. Aqueous humor HA levels in both patients with the XFS and the XFG were significantly higher compared to the controls., Conclusion: We suggest that bFGF plays an important role in the pathogenesis of XFS and XFG, as well as in the synthesis of secreted HA, which may result in connective tissue degradation that affects the ocular anterior segment.

Endophthalmitis is a well-recognized, frequently devastating ophthalmic disease. The colonization of the eye and the subsequent development of endophthalmitis may be exogenous (including postsurgical and post-traumatic infections) or it may be of endogenous origin, representing a metastasis from a focus of infection elsewhere in the body associated with bacteremia (such as meningitis or cellulitis).

Malondialdehyde (MDA) is considered as the most important marker for monitoring lipid peroxidation, which is strongly associated with the development of serious diseases in adults and premature neonates. In this paper we report a method for determination of free MDA in human plasma using capillary zone electrophoresis. MDA was separated and determined as conjugate with tetrabutylammonium hydrogen sulphate (TBAS). Analysis was performed using 20 mM borare, pH = 9.3, as operating buffer and detection of the MDA-TBAS adduct at 267 nm. The method has a linear range up to 80 microM with a detection limit of 0.2 microM. The method was applied to the analysis of MDA in plasma of healthy adults, normal-gestation infants and of preterm neonates. Plasma proteins were successfully removed following centrifugation through a centricon-3 membrane. Results showed that the method can be easily and accurate applied for the determination of MDA in human plasma and that the level of MDA in pretern neonates is significantly higher (p

Purpose: To evaluate contrast sensitivity function in patients with impaired oral glucose tolerance test (OGTT) compared with normal subjects., Methods: Sixteen patients with impaired OGTT and 11 normal control subjects were tested for contrast sensitivity function at four spatial frequencies. Glucose intolerance was established by the 1985 World Health Organization criteria., Results: The two groups were similar in terms of age, visual acuity, refractive correction, and lens opacities. A statistically significant loss of contrast sensitivity was associated with impaired OGTT (p < 0.001) in every spatial frequency tested., Conclusions: Functional visual loss in patients with impaired glucose tolerance using the 1985 World Health Organization criteria indicates that at least part of those patients should be classified as diabetic according to the 1997 American Diabetic Association criteria. It seems that the 1997 American Diabetic Association criteria are more efficient at detecting patients with abnormal visual function.

Purpose: To investigate contrast sensitivity function in patients with beta-thalassemia major, after regular transfusion and chelation therapy., Methods: We measured contrast sensitivity at four spatial frequencies in 30 patients with beta-thalassemia major and in 30 matched normal control subjects. All subjects underwent an ophthalmic examination that included fluorescein angiography. The contrast sensitivity results from the two groups were compared between them. Patients' contrast sensitivity values were correlated to the variables age, duration of transfusion, duration of chelation therapy and serum ferritin levels, to select the important predictors., Results: Contrast sensitivity function in all beta-thalassemic patients was significantly lower (p<0.0001) compared to the normal control subjects, for all spatial frequencies tested. The most important predictor of contrast sensitivity loss was patients' age., Conclusion: Contrast sensitivity testing can detect early changes in the visual function of beta-thalassemic patients and should be considered as a monitor for patients under chronic transfusion-chelation therapy.

The aim of this study was the development of a capillary electrophoretic method for the determination of the levels of the selective alpha(2)-adrenergic receptor agonist brimonidine in aqueous humor of the eye and blood sera and their relation to its efficacy in reducing the intraocular pressure (IOP). Analysis of brimonidine was performed by capillary zone electrophoresis using 20 mM borate, pH 9.3, as operating buffer and detection at 255 nm. Brimonidine levels were determined in aqueous humor and blood sera from seven patients admitted for cataract extraction following ocular administration of the ophthalmic Alphagantrade mark solution. Levels of brimonidine and IOP values were recorded for a 24 h period. Alphagantrade mark administration resulted in a significant reduction of IOP, from within 30 min up to 4-5 h, whereafter a stepwise increase was recorded until 24 h, where mean IOP value returned to that before administration. The IOP reduction was related to the levels of brimonidine in aqueous humor, where maximal levels (80-100%) were obtained within 1-3 h. A 50% amount of the solution was determined after 4-5 h, whereas it reached the minimum level after 12 h. Serum levels reached maximum within 3-4 h, a 50% reduction was recorded in 12 h and minimum level in 24 h. It is concluded that brimonidine administration may significantly reduce IOP in patients when its level is maintained >/=50% of the maximum present in aqueous humor, i.e within a 4-6 h period. Since at this time the level of brimonidine in blood serum has reached maximum value, administration of brimonidine every 6 h may be used to obtain adequate brimonidine levels to maintain a constantly lowered IOP., (Copyright 2000 John Wiley & Sons, Ltd.)

Objective: To investigate whether maternal smoking during pregnancy causes retinal abnormalities in the newborn., Study Design: One hundred sixty-two neonates of smoking mothers and 162 matched neonates of nonsmoking mothers (112 appropriate for gestational age [AGA], 30 small for gestational age [SGA], 20 large for gestational age [LGA] in each group) were studied., Results: Retinal arterial narrowing and straightening (RANS) was observed in 52 and 10 eyes of the newborns of smoking and nonsmoking mothers, respectively (P <. 000001) in association with elevated blood pressure in the neonates. The frequency of RANS was more than 3-fold greater in the SGA neonates than in the AGA and LGA neonates of the smoking mothers. Retinal venous dilatation and tortuosity (RVDT) was found in 100 and 36 eyes of neonates of smoking and nonsmoking mothers, respectively (P <.000001). The frequency of RVDT in the SGA neonates of the smoking mothers was 2.5-fold and 4.2-fold greater than in the AGA infants and the LGA infants, respectively. Also, intraretinal hemorrhages were found in 61 and 31 eyes of neonates of smoking and nonsmoking mothers, respectively (P =.0007) in association with elevated hematocrit and RVDT, whereas no intraretinal hemorrhages were found when RANS was present. All retinal abnormalities resolved by 6 months in infants of smoking mothers and by 2 months in infants of nonsmoking mothers., Conclusions: Maternal smoking during pregnancy causes increased frequency of RANS, RVDT, and intraretinal hemorrhages; but these retinal abnormalities resolve by 6 months of age.

Background and Objective: To evaluate the efficacy of topical brimonidine tartrate 0.2% (Allergan, Irvine, CA) in the prophylactic treatment of acute intraocular pressure (IOP) rises following Nd:YAG laser posterior capsulotomy., Patients and Methods: This was a double-masked, randomized, placebo-controlled clinical study in 60 patients who underwent Nd:YAG laser posterior capsulotomy after extracapsular cataract extraction. Two doses of brimonidine or vehicle were administered before and after capsulotomy. Intraocular pressure was measured prior to commencing instillation and for 48 hours postoperatively., Results: Following posterior capsulotomy, the brimonidine group showed a significant mean percent reduction in IOP, while the vehicle group showed a significant mean percent increase in IOP. At 48 hours, mean IOP of both groups had returned to pre-laser level. There were no differences between the 2 groups in the incidence of clinical adverse experiences., Conclusion: Two-dose brimonidine tartrate 0.2% effectively prevents acute IOP rises after Nd:YAG laser posterior capsulotomy.

Contrast sensitivity function after cataract extraction and intraocular lens implantation has been mainly correlated to the type or the material of the intraocular lens. Our purpose was to identify other possible factors, like posterior capsule, to contrast sensitivity alterations after cataract surgery, comparing patients operated for cataract by techniques that mainly differed on the posterior capsule's integrity. The intraocular lens implanted was either a posterior or an anterior chamber one, always monofocal and made of PMMA. We measured contrast sensitivity function at four spatial frequencies in two groups of operated individuals (group A and B) and in one group of healthy control individuals. Each group consisted of 42 eyes. Group A comprised eyes with intact, clear posterior capsule and posterior chamber monofocal intraocular lens. Group B comprised eyes with ruptured or removed posterior capsule and anterior chamber monofocal intraocular lens. Control group comprised healthy control eyes. A pair matched design was used to compare contrast sensitivity values among the individuals of the three groups. No statistically significant differences in contrast sensitivity values were found when group B patients were compared to healthy controls (p >0.05). Patients of group A exhibited contrast sensitivity function impairment at intermediate and high spatial frequencies when compared to patients of group B (p <0.05) and to controls (p <0.01). It seems that intact posterior capsule provides inferior visual function, in spite of relatively good visual acuity and apparently satisfactory results.