Differences in Central Corneal Thickness between Spectral Domain-Optical Coherence Tomography and Ultrasound Pachymetry in Patients with Dry Eye Disease.

Purpose. To compare central corneal thickness (CCT) values via Spectral Domain-Optical Coherence Tomography (SD-OCT) and ultrasonic pachymetry in patients with severe dry eye disease (DED) to determine the level of agreement between these 2 methods. Methods. The paired samples t-test was used to compare CCT values in severe DED patients. Matching analysis between methods was performed using intraclass correlation coefficient (ICC). Intrasession reliability of the measurement methods was calculated via the concordance correlation coefficient (CCC), variation equivalent, and Pearson's correlation coefficient. The Bland-Altman procedure was used to graphically represent the differences between CCT values. Results. The study included 56 eyes of 24 female and 4 male patients. Mean age of the patients was 50.9 ± 11.3 years. Mean CCT via Cirrus SD-OCT was 523.82 ± 30.98 µm versus 530.050 ± 31.85 µm via ultrasonic pachymetry (paired samples t-test, P < 0.001). The Bland-Altman plot showed good agreement between the examiners. The ICC for repeatability was 0.974. The CCC between the 2 methods' CCT values was 0.973. The variation equivalent was 0.976 and Pearson's correlation coefficient was 99.3%, which also indicated high correlation between the 2 methods' measurements. Conclusions. The present findings show that in patients with severe DED Cirrus SD-OCT provides reliable intraobserver CCT values.

Effects of chronic smoking on color vision in young subjects.

AIM: To evaluate the effects of chronic smoking on color vision in young subjects. METHODS: This study included 91 smokers and 88 non-smokers (a total of 179 volunteers) without any ophthalmologic and systemical disorders. The subjects were between 18-40 years of age with a best corrected visual acuity (BCVA) of 20/20, normal anterior and posterior segment examinations and normal intraocular pressure. The color vision of the subjects were evaluated with Farnsworth-Munsell 100 Hue test (FMHT). The total error scores and axis calculation were performed for each subject and the results correlated. RESULTS: Mean age and the standard deviation was 28±5y in the smokers group, and 26.7±5.5y in the control group (P=0.101). Sex distribution was similar in the two groups (P=0.365). There was no significant correlation between age and FMHT total error scores (P=0.069). Median of FMHT total error scores of smokers and non-smokers were 65 and 50.50, respectively. FMHT total error scores was found significantly higher in smokers than non-smokers (P=0.004). There was no statisticaly significant difference between smoker and non-smoker groups with respect to axis ratio calculation (P=0.611). There was no significant correlation with FMHT total error scores with neither smoking duration nor number of cigarettes smoked per day (P=0.405, P=0.454, respectively). CONCLUSION: This study suggested that chronic smoking affects the color vision of young smokers but this may not be sector selective.

The efficacy of autologous serum eye drops for severe dry eye syndrome: a randomized double-blind crossover study.

BACKGROUND: To evaluate the efficacy of autologous serum (AS) eye drops for the symptomatic relief of severe dry eye syndrome (DES), as compared to conventional preservative-free artificial tears (PFAT). METHODS: This prospective double-blind randomized crossover study used the Ocular Surface Disease Index (OSDI), tear film break-up time (TBUT), Schirmer's Test, and OXFORD Scale at baseline and after each of two 1-month treatment periods to measure the effect of 20 % diluted AS eye drops vs. PFAT in 20 consecutive severe DES patients that were refractory to conventional treatment. RESULTS: The study included 20 (18 female and two male) severe DES patients (40 eyes). Significantly higher TBUT (P < 0.001, Wilcoxon signed-rank test) and a greater decrease in OSDI score (55.18 % decrease in the AS treatment group vs. 19.50 % decrease in the PFAT treatment group) (P < 0.001, Student's paired samples t-test) were observed in the AS treatment group after 1 month of treatment. There wasn't a significant difference in Schirmer's test and OXFORD conjunctival and corneal vital dying grading scores between the two treatment groups after 1 month of treatment (P > 0.05 [Mann-Whitney U test]). CONCLUSIONS: AS eye drops were more effective than conventional eye drops for improving tear film stability and subjective comfort in patients with severe DES.

Overexpression of vascular endothelial growth factor receptor 2 in pterygia may have a predictive value for a higher postoperative recurrence rate.

BACKGROUND: To investigate the expression levels of vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor 1 (VEGFR-1) and VEGFR-2 in pterygium and to clarify the prognostic significance of these expressions in pterygia. METHODS: A total of 40 surgically excised pterygia and 9 normal conjunctivae were immunohistochemically studied applying the streptavidin-biotin method in paraffin-embedded tissue sections. Monoclonal antibodies were targeted against VEGF, VEGFR-1 and VEGFR-2 proteins. At the sixth postoperative month, the recurrence rate was graded on a scale of 1-4. RESULTS: The mean percentage of VEGF-positive epithelial cells was comparable in pterygium and normal conjunctivae. However, the pterygium group presented higher expression levels of VEGF in pterygia endothelial cells (p=0.05). In terms of VEGFR-1 expression in epithelial cells, no statistically significant difference was found between two groups (p=0.658). However, normal conjunctivae exhibited higher expression levels of VEGFR-1 in endothelial cells (p=0.002). Epithelial cells in pterygium presented higher combined scores of VEGFR-2 (87.5% and 22.2%, respectively) (p=0.013). While higher expression levels of VEGFR-2 were documented in pterygia endothelial cells, no VEGFR-2 immunoreactivity was observed in the endothelial cells of normal conjunctivae (p<0.001). Expression levels of VEGFR-2 in epithelial cells and endothelial cells were positively correlated with the postoperative recurrence grading system (p<0.001 and τ=0.627, p=0.001 and τ=0.508, respectively). CONCLUSIONS: The results suggest that VEGF may play a key role through VEGFR-2 in the pathogenesis of pterygium. Moreover, overexpression of VEGFR-2 in pterygia may have a predictive value for a higher postoperative recurrence rate.

Age-related change in retinal nerve fiber layer thickness measured with spectral domain optical coherence tomography.

PURPOSE: We investigated age-related change in peripapillary retinal nerve fiber layer thicknesses (RNFLT) measured with spectral domain optical coherence tomography (SD-OCT) in healthy individuals. METHODS: In this cross-sectional study, peripapillary RNFL measurement was performed using a Cirrus SD-OCT device. Linear regression analysis and Spearman's correlation analysis were performed to investigate the level of difference in age-related change in the overall mean, 4 quadrants mean, and 12 clock-hour sectors mean RNFLT. RESULTS: Mean age of the 121 healthy participants was 39 years (range, 20-59 years). Mean 4 quadrant and mean 12 clock-hour sector RNFLT in the 121 randomly selected eyes in 121 healthy participants decreased significantly with age in the overall group (Spearman's correlation analysis, P < 0.05). Overall mean RNFLT decreased by 0.365 µm (95% confidence interval [CI], 0.47-0.26; linear regression analysis, P < 0.001) for every one year increase in age. Overall, the greatest decrease in mean RNFLT was in the lower quadrant (0.575 µm/y; 95% CI, 0.733-0.416), versus the least decrease in the nasal quadrant (0.141 µm/y; 95% CI, 0.272-0.010), and the greatest decrease in mean RNFLT was in the 6 clock-hour sector (0.656 µm/y; 95% CI, 0.939-0.374), versus the least decrease in the 3 clock-hour sector (0.119 µm/y; 95% CI, 0.266-0.029). CONCLUSIONS: Age-related decrease in RNFLT varied according to sector. Age-related change should be accounted for in any assessment of RNFLT. Regional age-related change is accounted for by Cirrus SD-OCT in its normative database.

Corneal endothelial characteristics and central corneal thickness in a population of Turkish cataract patients.

OBJECTIVES: The aim was to assess corneal endothelial characteristics and central corneal thickness (CCT) in a population of Turkish cataract patients and to define the impact of age and gender on these parameters. METHODS: Five hundred and seventeen cataract patients were examined with noncontact specular microscope preoperatively. The eye planned to be operated was selected for analysis. The parameters measured were endothelial cell density (ECD), cell area (CA), coefficient of variation (CV) of the CA, percentage of hexagonal cells (PHCs), and CCT. RESULTS: The mean values in ECD, CA, CV, PHC, and CCT in all eyes were 2,258 ± 474 cells per square millimeter, 468 ± 130 µm(2), 39%±7%, 49%±12%, and 500 ± 37 µm, respectively. Regression analysis revealed a statistically significant decrease in ECD (R=-0.169, P<0.0001), increase in CA (R=0.186, P<0.0001), and decrease in the CCT (R=-0.122, P=0.006) with increase in age. The changes in the CV (R=0.008, P=0.861) and PHC (R=-0,060, P=0.177) were not found to be dependent on age. The parameters showed no sex differences. The number of eyes with ECD below 1,000 and 2,000 cells per square millimeter was 5 (0.97%) and 130 (25.1%), respectively. CONCLUSIONS: The data from our study emphasize that age, but not gender, is the main determinant of ECD.

Topical cyclosporine A as a steroid-sparing agent in steroid-dependent idiopathic ocular myositis with scleritis: a case report and review of the literature.

OBJECTIVE: To report on a case of idiopathic orbital myositis with scleritis that was effectively controlled with topical 0.05% cyclosporine A and to provide a review of the literature on the treatment of ocular myositis with scleritis. METHODS: A case report. RESULTS: A 35-year-old woman presented with a longstanding history of intractable periorbital pain, redness on her left eye, and diplopia during ocular movement. Her medical history revealed that she had the same symptoms for 5 years and had used numerous prescribed medications for migraine and ocular myositis. During this period, her symptoms and signs had been lessened on systemic steroid treatment, which recurred or worsened after discontinuing or tapering the therapy. Magnetic resonance imaging scans demonstrated an isolated enlargement of the left medial rectus muscle. Laboratory examination results showed no evidence of dysthyroid ophthalmopathy or another systemic disease. Because of adverse affects of systemic corticosteroid and cyclosporine treatments, topical cyclosporine A (0.05%) and dexamethasone were administered four times daily. The patient continued to use topical 0.05% cyclosporine A for 6 months. Using only topical cyclosporine A, she currently has no recurrences of disease on the last examination after 6 months of treatment. Moreover, magnetic resonance imaging revealed a completely normal extraocular muscle configuration. CONCLUSIONS: Topical 0.05% cyclosporine A may be a safe and effective long-term treatment of ocular myositis and scleritis. It should be considered as a steroid-sparing agent, particularly in recurrent disease and in those patients who experience adverse effects of systemic medications.

Physicochemical properties of collagen sheet from bovine femur.

PURPOSE: In the present study collagen sheets were prepared from the spongy part of the bovine femur and characterized from the physicochemical point of view. METHODS: The physicochemical properties of the collagen sheets were studied using scanning electronic microscopy (SEM) and thermogravimetrical analysis (TGA). RESULTS: The SEM studies showed that the collagen sheets are porous and exhibit a fibrous nature. The TGA study revealed that the collagen sheets are a two-phase system containing a protein and a mineral phase. In order to determine the collagen type present in the sample, the sheets were dissolved and studied by circular dichroism (CD) and electrophoresis techniques. The results obtained showed that the nature of the collagen is type I. CONCLUSIONS: The type I collagen sheets from bovine femur isolated in this study are proposed as a biomaterial for medical applications, for example, as an osteoinductive material or they could be used as a bone substitute.

Schizophrenia in an adult with 6p25 deletion syndrome.

Chromosomal deletions at 6p25-p24 are rare findings in patients with developmental delay. There is limited information about the adult phenotype. We present a 36-year-old patient with schizophrenia, mild mental retardation, progressive hearing deficits, and characteristic facial features. Ocular (Axenfeld-Rieger anomaly) abnormalities were diagnosed in infancy; vision, however, has remained unimpaired. There were no other major congenital anomalies. Brain imaging showed only minor changes. There was no family history of intellectual deficits or psychosis. Karyotyping revealed a 6p25 deletion, and detailed fluorescence in situ hybridization (FISH) analyses using 23 probes confirmed a 6.7 Mb 6p25-pter deletion. The breakpoint is near a possible 6p25-p24 locus for schizophrenia. Psychotic illness may be part of the neurodevelopmental abnormalities and long-term outcome of patients with 6p terminal deletions. Other similarly affected patients likely remain to be diagnosed in adult populations of schizophrenia and/or mental retardation.

Mapping of three translocation breakpoints associated with orofacial clefting within 6p24 and identification of new transcripts within the region.

Orofacial clefting (OFC) is a common congenital malformation. Here we report the refinement of three translocation breakpoints of patients exhibiting OFC within the 6p24 region, and the isolation and characterisation of novel genes, one of which is directly disrupted by the translocation breakpoint of a patient. The gene has been characterized and orthologues identified in bovine, murine and pufferfish.

Nitric oxide levels in tears of patients with mild forms of papillary conjunctivitis induced by rigid gas-permeable contact lenses.

PURPOSE: To determine whether nitric oxide (NO) is detectable in the tear fluid of patients with mild forms of papillary conjunctivitis who wear rigid gas-permeable contact lenses. METHODS: Tear samples were taken from 12 users of rigid gas-permeable contact lenses and 12 healthy controls. Samples were analyzed, and the levels of NO were determined. RESULTS: The mean level of NO in those who wore contact lenses was 118.98 micromol/L (95% CI: 91.85-146.10 micromol/L); whereas the level of NO found in the control subjects was 114.84 micromol/L (95% CI: 102.54-127.14 micromol/L). The difference was statistically insignificant (P>0.05). CONCLUSION: Nitric oxide levels in the tear fluid of rigid gas-permeable contact lens users did not correlate with the presence of mild symptoms of papillary conjunctivitis.

Molecularly defined interstitial tandem duplication 6p case with mild manifestations.

An interstitial tandem duplication of 6p21.1-p22.2 was found in a girl at 11 months of age when she was evaluated for developmental delay. Previous cases reported with partial 6p duplication usually have involved terminal duplications, with breakpoints ranging from 6p11 to 6p25. Our patient exhibits a milder phenotype compared to the previously reported cases in the literature. Features that she has in common with the other cases include craniofacial anomalies, such as broad nasal bridge and bulbous tip, thin lips, incomplete development of the scapha helix bilaterally, mild spastic paraparesis of the lower extremities, gross motor delay, and mild cognitive delays.

Tear nitrite and nitrate levels as nitric oxide end products in patients with Behçet's disease and non-Behçet's uveitis.

To evaluate the role of nitric oxide (NO) in ocular inflammation, tear nitrite and nitrates (NN) as NO end products were determined in 11 patients with Behçet's disease (BD) and in 11 with non-Behçet's uveitis (NBU) during the active and remission stages and in 12 healthy controls. Median (with the range) NN levels were 82.29 (59. 60-98.25) micromol/l in the active and 98.25 (52.88-246.92) micromol/l in the remission stage of BD; 88.17 (25.99-116.73) micromol/l in the active and 83.00 (31.04-250.28) micromol/l in the remission stage of NBU and 109.17 (88.17-158.74) micromol/l in the controls. The NN levels in the active stage of BD and NBU were significantly decreased when compared to the controls (p < 0.05; Kruskal-Wallis test). Decreased NN levels at the activation stage may be caused by the rapid transformation of the NO to peroxynitrites, which are highly oxidizing and cytotoxic substances.

Comparison of the effects of 0.5% timolol maleate, 2% carteolol hydrochloride, and 0.3% metipranolol on intraocular pressure and perimetry findings and evaluation of their ocular and systemic effects.

PURPOSE: To compare the effects of 0.5% timolol maleate, 2% carteolol, and 0.3% metipranolol on intraocular pressure (IOP) in 45 patients with primary open-angle glaucoma (POAG) and ocular hypertension. A secondary goal of this study was to evaluate the ocular and systemic side effects of these medications. METHODS: Measurements of IOP were taken at baseline (pretreatment) and 2, 6, and 12 hours after instillation on treatment days 15, 30, 60, and 90. Mean sensitivity (MS) and mean defect (MD) values of perimetry before and after treatment and the effects of the three beta blockers on serum lipid profiles were determined. Ocular and systemic side effects were recorded. RESULTS: The most prominent IOP lowering effect was noted with metipranolol at 2 and 6 hours on day 15, and with timolol maleate at 12 hours on day 15 and at all hours of the subsequent days on which measurements were taken. Timolol maleate produced a significant decrease in IOP at 12 hours on day 15 compared with carteolol. There was not a statistically significant difference between the MS and MD values on perimetry before and after treatment for any treatment. There was a statistically significant decrease in levels of total cholesterol and high-density lipoprotein (HDL) cholesterol and a significant increase in triglyceride levels; these changes were observed for all treatments. CONCLUSION: The effects of the three medications were not statistically different from each other in terms of IOP reduction and visual field changes. Careful monitoring of blood lipid levels is necessary with long-term treatment with beta blockers, because these agents reduced serum levels of HDL and total cholesterol while increasing triglycerides. Such changes in lipid levels could lead to increased incidence of complications, particularly in patients with atherosclerosis or coronary heart disease.

Ophthalmological effects of high altitude.

High altitude has various effects on human beings. Altitude-related illnesses are a frequent cause of morbidity and occasional mortality in travelers to high altitudes throughout the world. The mountaineers all around the world are familiar with this condition, which is called acute mountain sickness (AMS). The primary altitude illnesses are AMS, high-altitude pulmonary edema and high-altitude cerebral edema. Altitude has potential undesired ophthalmological effects. The pathogenesis of these syndromes remains unclear despite considerable research in this field. Most of these problems are primarily preventable with an adequate level of information before and during travel. Further studies are needed to reveal the exact relationship between high altitude and ophthalmological findings. In this article, ophthalmological effects of high altitude, likely to be encountered by mountaineers as well as other enthusiasts of high altitude sports are reviewed. Emphasis on aviation and aerospace medicine is briefly given under related SUB_TITLEs.

An interstitial deletion of 6p24-p25 proximal to the FKHL7 locus and including AP-2alpha that affects anterior eye chamber development.

The FKHL7 gene has been implicated in the pathogenesis of glaucoma/autosomal dominant iridogoniodysgenesis (IGDA) (IRID1). This has been supported by mutations in some glaucoma and IGDA patients and the development of anterior eye chamber anomalies in patients with 6p deletions affecting the 6p25 region. We report a case with anterior eye chamber anomalies and an interstitial deletion of 6p24-p25 that does not include the FKHL7 gene, suggesting the possible additional involvement of another locus, within 6p24-6p25, in anterior eye chamber development. A candidate gene is AP-2alpha, which is contained within the deleted segment and plays a role in anterior eye chamber development.

Human epidermal differentiation complex in a single 2.5 Mbp long continuum of overlapping DNA cloned in bacteria integrating physical and transcript maps.

Terminal differentiation of keratinocytes involves the sequential expression of several major proteins which can be identified in distinct cellular layers within the mammalian epidermis and are characteristic for the maturation state of the keratinocyte. Many of the corresponding genes are clustered in one specific human chromosomal region 1q21. It is rare in the genome to find in such close proximity the genes belonging to at least three structurally different families, yet sharing spatial and temporal expression specificity, as well as interdependent functional features. This DNA segment, termed the epidermal differentiation complex, contains 27 genes, 14 of which are specifically expressed during calcium-dependent terminal differentiation of keratinocytes (the majority being structural protein precursors of the cornified envelope) and the other 13 belong to the S100 family of calcium binding proteins with possible signal transduction roles in the differentiation of epidermis and other tissues. In order to provide a bacterial clone resource that will enable further studies of genomic structure, transcriptional regulation, function and evolution of the epidermal differentiation complex, as well as the identification of novel genes, we have constructed a single 2.45 Mbp long continuum of genomic DNA cloned as 45 p1 artificial chromosomes, three bacterial artificial chromosomes, and 34 cosmid clones. The map encompasses all of the 27 genes so far assigned to the epidermal differentiation complex, and integrates the physical localization of these genes at a high resolution on a complete NotI and SalI, and a partial EcoRI restriction map. This map will be the starting resource for the large-scale genomic sequencing of this region by The Sanger Center, Hinxton, U.K.

Delineation of two distinct 6p deletion syndromes.

Deletions of the short arm of chromosome 6 are relatively rare, the main features being developmental delay, craniofacial malformations, hypotonia, and defects of the heart and kidney, with hydrocephalus and eye abnormalities occurring in some instances. We present the molecular cytogenetic investigation of six cases with 6p deletions and two cases with unbalanced translocations resulting in monosomy of the distal part of 6p. The breakpoints of the deletions have been determined accurately by using 55 well-mapped probes and fluorescence in situ hybridization (FISH). The cases can be grouped into two distinct categories: interstitial deletions within the 6p22-p24 segment and terminal deletions within the 6p24-pter segment. Characteristics correlating with specific regions are: short neck, clinodactyly or syndactyly, brain, heart and kidney defects with deletions within 6p23-p24; and corneal opacities/iris coloboma/Rieger anomaly, hypertelorism and deafness with deletions of 6p25. The two cases with unbalanced translocations presented with a Larsen-like syndrome including some characteristics of the 6p deletion syndrome, which can be explained by the deletion of 6p25. Such investigation of cytogenetic abnormalities of 6p using FISH techniques and a defined set of probes will allow a direct comparison of reported cases and enable more accurate diagnosis as well as prognosis in patients with 6p deletions.

Molecular cloning, chromosomal mapping, and developmental expression of a novel protein tyrosine phosphatase-like gene.

Protein tyrosine phosphatases (PTPs) mediate the dephosphorylation of phosphotyrosine. PTPs are known to be involved in many signal transduction pathways leading to cell growth, differentiation, and oncogenic transformation. We have cloned a new family of novel protein tyrosine phosphatase-like genes, the Ptpl (protein tyrosine phosphatase-like; proline instead of catalytic arginine) gene family. This gene family is composed of at least three members, and we describe here the developmental expression pattern and chromosomal location for one of these genes, Ptpla. In situ hybridization studies revealed that Ptpla expression was first detected at embryonic day 8.5 in muscle progenitors and later in differentiated muscle types: in the developing heart, throughout the liver and lungs, and in a number of neural crest derivatives including the dorsal root and trigeminal ganglia. Postnatally Ptpla was expressed in a number of adult tissues including cardiac and skeletal muscle, liver, testis, and kidney. The early expression pattern of this gene and its persistent expression in adult tissues suggest that it may have an important role in the development, differentiation, and maintenance of a number of different tissue types. The human homologue of Ptpla (PTPLA) was cloned and shown to map to 10p13-p14.