Effect of smoking on retina nerve fiber layer and ganglion cell-inner plexiform layer complex

Purpose: The aim of this study is to show the effects of smoking on retina layers, especially retina nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer complex (GCIPL).

Materials and methods: Participants smoking for more than 10 years at least 1 pack of cigarettes a day and a control group, both including participants between ages of 20 and 50 years with no other systemic or ocular diseases were studied. After normality tests, an independent sample t test was used to analyze the differences in age, sex, spherical equivalent (SE), intraocular pressure (IOP), axial length (AL), GCIPL and RNFL values between the groups.

Results: There were 44 participants in each group. There were 32 (62.5%) men and 12(37.5%) women in smokers and 36 (77.88%) men and 8 (22.22%) women in control group. Mean ages were 39.85?±?8.41 and 38.66?±?10.47 years, mean spherical equivalent (SE) values were ?0.15?±?0.4 and 0?±?0.29 dioptries in smokers and control groups, respectively. The IOP, AXL, GCIPL and RNFL values were 17.58?±?3.41?mmHg, 23.69?±?0.56?mm, 84.3?±?5.83?μm and 92.3?±?3.51?μm in the smokers group and 18.5?±?2.91?mmHg, 23.45?±?0.72?mm, 86.11?±?8.02?μm and 97.66?±?8.23?μm in the control group. The inferior, superior, nasal and temporal values of RNFL quadrants were 123.18?±?26.14, 117.05?±?5.51, 64.95?±?8.67 and 63.5?±?6.88?μm in the smokers group and 130.81?±?11.8, 123.55?±?11.03, 72.44?±?9.84 and 58.44?±?7.48?μm in the control group. There were no significant difference of age, sex, SE, IOP, AXL and GCIPL values between the smokers and control groups (p?>?0.05). The mean RNFL was significantly thinner in the smokers group compared to controls (p?=?0.03, independent t test). Inferior and superior quadrants of RNFL decreased in smokers group (p?=?0.01 and p?=?0.03, respectively) but temporal and nasal quadrants did not seem to be changed (p?=?0.96 and p?=?0.07, respectively).

Discussion: Smoking may affect RNFL thickness but not GCIPL.     

Ocular surface changes following oral anticholinergic use for overactive bladder

Objective: To investigate the effect of oral solifenacin succinate on Schirmer I test results, tear break-up time (TBUT) and Ocular Surface Disease Index (OSDI) scores in overactive bladder (OAB) patients and to compare these results with those of healthy control subjects.

Materials and methods: The female OAB patients who were prescribed oral solifenacin succinate 5?mg/day (Group I, N?=?80) and age-matched healthy female subjects (Group II, N?=?40) were recruited for the study and underwent ophthalmological examination prior to oral treatment and after 4 weeks. They completed the OSDI questionnaire and underwent ocular surface tests including Schirmer I test and TBUT.

Results: The statistical analysis of the Schirmer I test and TBUT revealed no significant difference between the baseline and 4th week values in both groups (Group I, p?=?0.506 and p?=?0.070 consecutively) (Group II, p?=?0.810 and p?=?0.823 consecutively). OSDI scores were found to be significantly increased in group I (21.8?±?4.2 vs 23.1?±?4.6, p?=?0.020) and remained unchanged in group II (20.5?±?7.0 vs 20.7?±?7.0, p?=?0.805).

Conclusions: Short-term solifenacin succinate treatment has no effect on the Schirmer I test results and TBUT, but ocular surface symptoms appeared to be exacerbated in respect with increased OSDI scores. However, the clinical significance needs to be further evaluated with larger studies.     

Effect of chronic smoking on lens nucleus as assessed by Pentacam HR lens densitometry in young adults

Objective: To evaluate the effects of chronic tobacco smoking on lens nucleus by Pentacam HR lens densitometry (LD) in young adults.

Design: Prospective cross-sectional case series.

Methods: Thirty subjects (23?M, 7 F) who were chronic cigarette smokers (≥10 cigarettes/day for at least 2 years) (group 1) and another 30 subjects (23?M, 7 F) who did not smoke (group 2), were included in this study. The patients were matched for age and sex between the groups. The exclusion criteria were any history of ocular surgery, any systemic disorders and any ocular diseases except for mild refractive disorders. Lens densitometry measurements were done with the Pentacam HR (Oculus, Wetzlar, Germany). The Schirmer test and pachymetry measurements were also performed.

Results: Mean age of the patients for both groups was 28.90?±?8.20 years (range: 18–40 years). Mean lens densitometry (LD) measurements of Group 1 (chronic cigarette smoking group) were higher than those of Group 2 (control group) in all LD techniques; however only mean “peak” LD measurements showed a statistically significant difference between these two groups (Group 1: 8.67?±?0.61, Group 2: 8.44?±?0.70, p?=?0.04). The mean Schirmer test value was 12.43?±?5.60?mm in Group 1 and 13.00?±?4.26?mm in Group 2 (p?=?0.55). The mean central corneal thickness (CCT) value was 564.23?±?34.61?µm in Group 1 and 550.47?±?32.94?µm in Group 2 (p?=?0.03).

Discussion: The Pentacam HR LD seems to be an important option for the evaluation of lens nucleus in young adults, because it gives objective and quantitative data.

Conclusion: Although chronic smoking increases lens nucleus density in young adults, the effect is not statistically significant when compared with the control group.     

The effect of voluntary fasting and dehydration on posterior ocular structures

Purpose: Islamic Ramadan is the month of fasting, in which intake of food and drink is restricted from sunrise until sunset. The objective of the present study was to find out the effects of religious fasting on posterior ocular structures.

Materials and methods: In this prospective study, 34 eyes of 34 healthy volunteers with a mean age of 34.09?±?7.20?years were enrolled. Volunteers with any systemic disorder and eyes with pathology or previous surgery were excluded. One week before Ramadan (non-fasting period) and during Ramadan (fasting period) at the same hours (at 08:00 and 16:00?h), choroidal, macular, and retinal nerve fibre layer (RNFL) thicknesses were measured by spectral domain optical coherence tomography. Results were compared using paired sample t-test, and a p value <0.05 was accepted as statistically significant.

Results: The comparison of 16:00-h measurements significantly revealed lower values during fasting period when compared non-fasting period for choroidal thickness (non-fasting and fasting, respectively; subfoveal: 299.26?±?41.3 and 280.03?±?38.75 p?p?p?=?0.001) and paracentral macular thickness (superior: p?=?0.002, inferior: p?=?0.010, temporal: p?=?0.013, and nasal: p?=?0.016). By contrast, no significant differences were found in the central macular thickness between the fasting and non-fasting periods (p?=?0.735). Also, no statistically significant difference was noted for RNFL thickness at the different periods and time points.

Conclusion: Our results reveal that Islamic religious fasting is associated with statistically significant alterations in choroidal and paracentral macular thickness in healthy volunteers. However, more detailed investigations should be designed to evaluate whether fasting has a pivotal influence on pathological conditions.     

Evaluation of the effects on choroidal thickness of bimatoprost 0.03% versus a brinzolamide 1.0%/timolol maleate 0.5% fixed combination

Objective: To investigate the effects of two different medical treatment options on choroidal thickness (CT) in cases of open-angle glaucoma (OAG).

Methods: Sixty-seven eyes newly diagnosed with OAG and 52 healthy eyes constituting the control group were included in the study. Glaucomatous eyes were randomly divided into two subgroups; Group I was started on bimatoprost 0.03% and Group II on a brinzolamide 1.0%/timolol maleate 0.5% fixed combination (BTFC). Intraocular pressure (IOP), ocular pulse amplitude (OPA) and subfoveal CT measurements were performed in all eyes in the study before treatment and on weeks 2, 4 and 8 after treatment.

Results: Mean initial IOP values in groups I and II and the control group were 25.5?±?4.7, 25.1?±?5.2 and 16.1?±?2.9?mmHg, mean OPA values were 3.7?±?1, 3.6?±?1.4 and 2.4?±?0.6?mmHg and mean CT values were 269.4?±?83, 264.5?±?84.4 and 320.1?±?56.6?μm, respectively. Eight weeks after treatment, mean IOP values in Groups I and II and the control group were 18.3?±?2.6, 18.1?±?3.4 and 15.7?±?2.9?mmHg, mean OPA values were 2.9?±?1.2, 2.8?±?1.5 and 2.3?±?0.8?mmHg and mean CT values were 290.2?±?87.3, 271.8?±?82.5 and 319.3?±?56.8?μm, respectively. No significant difference was determined in terms of the decrease in IOP and OPA obtained after treatment in Group I and Group II. However, a significant difference was observed between the two groups in terms of choroidal thickening after treatment.

Conclusion: The use of topical ocular hypotensive medication in eyes with OAG results in an increase in CT. This increase is relatively greater with bimatoprost 0.03% therapy compared to BTFC.     

Evaluation of the tear film instability in children with allergic diseases

Context: The presence of dry eye syndrome (DES) in ocular allergic diseases was evaluated in several studies. Despite this, little exists about the tear film instability in atopic children including patients with allergic rhinitis (AR), allergic conjunctivitis (AC) and asthma. This is a study which presents intriguing findings regarding the relationship of tear film instability with clinical aspects in atopic children.

Objective: To determine the tear film instability in children with AR, AC and asthma.

Materials and methods: One hundred and thirty-five consecutive children with AR, AC and asthma as study group and 45 children without any systemic and ocular abnormality as control group were included in the study. Skin prick tests, measurement of tear film breakup time (TFBUT), serum immunoglobulin E and eosinophil counts were performed in all patients. Also four subgroups of patients were designated as AR group (Group I), AC group (Group II), asthma group (Group III) and control group (Group IV).

Results: Socio-demographic characteristics were similar except for family atopy between the groups (p?>?0.05). The mean TFBUT was significantly lower in the study group (15.5?±?4.4?s) than the control group (18.4?±?2.9?s; p?=?0.000). Also, there was no significant differences in the percentage of the patients who has TFBUT<10?s (p?=?0.066). In logistic regression analysis, atopy was found to be the determinant of lower TFBUT (OR?=?16.33, 95%; CI?=?1.17 to 228.05, p?=?0.03).

Conclusion: The presence of tear film instability was higher in children with AC, AR and asthma. This finding should be taken in consideration in atopic children.     

Evaluation of the peripapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer measurements in patients with iron deficiency anemia with optical coherence tomography

Objective: To evaluate the thickness of the peripapillary retinal fiber layer (RNFL) and macula ganglion cell-inner plexiform layer (GCL+) using optical coherence tomography (OCT) in patients with iron deficiency (ID) anemia.

Methods: This study included 73 eyes of 39 patients with ID anemia and 68 eyes of 34 age- and sex-matched healthy subjects. The measurements included the peripapillary RNFL thicknesses as average, 4 quadrant and 12 clock-hour (CH) based and macula GCL+ thicknesses as average and 6 quadrant based. All measurements were completed with Cirrus HD-OCT and the results were compared between the groups.

Results: A total of 73 eyes of 39 patients with ID anemia and 68 eyes of 34 healthy subjects were included to the study. Regarding peripapillary RNFL thicknesses of the study and control patients, the values of average and quadrants revealed no significant differences between the groups. In CH sectors comparison, peripapillary RNFL thicknesses were significantly decreased only in CH4 (68.7?±?14.5?μm in study versus 72.0?±?13.4?μm in control patients, p?=?0.049) and CH5 (93.4?±?20.0μm in study versus 102.2?±?20.1?μm in control patients, p?=?0.01) sectors. All measured quadrants were statistically similar, when macula GCL+ thicknesses were compared between the groups. When the correlations between peripapillary RNFL and macula GCL+ thicknesses and serum hemoglobin and ferritin levels of study and control patients were calculated, the only statistically significant parameter was the correlation of peripapillary RNFL thickness in CH10 sector with serum ferritin level (p?=?0.032, Spearman correlation coefficient: 0.369).

Conclusion: The study revealed that peripapillary RNFL is thinner in nasal-inferior quadrant in patients with ID anemia. The measurements of macula GCL+ thicknesses were similar between the groups. Analyzing the retinal layers using OCT may provide valuable information in neurodegenerative events.     

Spectral domain-optical coherence tomographic findings in patients with ankylosing spondylitis under anti-tumor necrosis factor-alpha therapy

Objective: To evaluate the effect of tumor necrosis factor-alpha (TNF-α) blockade on the thickness of the peripapillary retinal nerve fiber layer (RNFL), the ganglion cell-inner plexiform layers (GCIPL), and the macula in ankylosing spondylitis (AS) patients under anti-TNF-α therapy.

Materials and methods: Twenty-one patients with AS received etanercept, or adalimumab, or infliximab for at least 6 months. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) levels, and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores were measured before and 6 months after the beginning of the treatment. Peripapillary RNFL, four regional fields (superior, inferior, nasal, and temporal), GCIPL, and macular thicknesses of the patients were analyzed by optical coherence tomography before the treatment, at 3 months and 6 months after the beginning of the treatment.

Results: The mean BASDAI, ESR, and CRP values were 5.2?±?1.5, 31.6?±?21.7, and 15.7?±?13.9, respectively, at the beginning of the treatment and 2.3?±?1.7, 21.3?±?15.1, and 10.1?±?10.3, respectively, 6 months after the beginning of treatment. There were significant differences among the mean BASDAI, ESR, and CRP values at the beginning of treatment and 6 months later (p?p?=?0.007, and p?=?0.009, respectively). There were no significant differences among peripapillary RNFL (p?=?0.24), four regional fields (p?=?0.98, p?=?0.23, p?=?0.09, p?=?0.47), GCIPL (p?=?0.25), or macular (p?=?0.33) thicknesses of the patients during anti-TNF-α treatment. In addition, the mean intraocular pressure levels throughout the follow-up did not show significant variation on repeated-measures ANOVA (p?=?0.77).

Conclusions: TNF-α blockade does not seem to influence RNFL, GCIPL, or macular thickness of patients with AS in the short term.     

The effects of smoking on dry eye parameters in healthy women

Aim: To investigate the effects of chronic smoking on dry eye parameters.

Methods: Ocular surface disease index (OSDI) and tear function tests such as Schirmer’s test, tear break-up-time (TBUT) test and impression cytology of 63 female chronic smokers and 40 age-matched female non-smokers were analyzed statistically.

Results: The mean OSDI scores, Schirmer test results and TBUT levels were 35.85?±?24.01 point, 14.25?±?5.94?mm and 5.17?±?2.85?s in chronic smokers and 15.20?±?12.93 point, 15.48?±?7.01?mm and 10.03?±?3.44?s in non-smokers, respectively. Differences in OSDI scores, TBUT levels and impression cytology grades among the chronic smokers and non-smokers were statistically significant.

Conclusion: Smoking behavior seems to affect the dry eye parameters negatively.     

Specific IgE for wheat in tear fluid of patients with allergic conjunctivitis

Context: Allergy to hydrolyzed wheat protein in facial soap has become a major social issue in Japan. It has been reported that the most frequent early symptoms of allergy to hydrolyzed wheat protein in soap are allergic conjunctivitis and rhinitis, while wheat-dependent exercise-induced anaphylaxis can be induced by long-term use.

Objective: We evaluated the relation between tear fluid levels of specific IgE for wheat and the features of allergic conjunctivitis.

Methods: A prospective, non-randomized, cross-sectional study was conducted in 103 patients with moderate to severe allergic conjunctivitis (allergic group) and 20 age- and sex-matched healthy control subjects (control group). Specific IgE for wheat was measured in tear fluid with an immunochromatography assay, and a skin prick test (SPT) was also performed. Symptoms (sneezing, rhinorrhea, nasal obstruction, ocular itching, and lacrimation) were assessed in each subject along with the activities of daily living (ADL) score and the total ocular symptom score for allergic conjunctivitis. A severity score (0, 1, 2, or 3) was assigned for various changes of the palpebral and bulbar conjunctiva, as well as for limbal and corneal lesions associated with allergic conjunctivitis.

Results: The IgE positive rate and specific IgE score were both higher in the allergic group than in the control group (71.8% versus 40.0% and 1.9?±?0.7 versus 1.4?±?0.5). A positive SPT for wheat was also more frequent in the allergic group than in the control group (6.8% versus 0.0%). Within the allergic group, patients with a positive SPT had higher specific IgE scores than patients with a negative SPT (3.3?±?0.5 versus 1.8?±?0.6, p?r?=?0.665), tearing (r?=?0.672), and the total ocular symptom score (r?=?0.204). Wheat IgE in tear fluid was also correlated with the severity of rhinitis symptoms, including sneezing (r?=?0.610), nose blowing (r?=?0.640), and nasal obstruction (r?=?0.677). Furthermore, the tear fluid wheat IgE score was correlated with five objective features of allergic conjunctivitis (p?Conclusions: These results suggest that wheat allergy may be involved in the development of allergic conjunctivitis.     

Peripapillary choroidal thickness in patients with chronic obstructive pulmonary disease

Objective: To evaluate the peripapillary choroidal thickness of patients with chronic obstructive pulmonary disease (COPD) via enhanced depth imaging optical coherence tomography (EDI-OCT).

Materials and methods: A total of 80 patients with COPD (80 eyes) and 50 control subjects (50 eyes) were enrolled. Choroidal scans and the retinal nerve fiber layer (RNFL) thickness were obtained for all eyes using OCT.

Results: The average peripapillary choroidal thickness measurements of the COPD group (147.58?±?53.53?μm) were lower than the control group (160.84?±?44.73?μm) (p?=?0.068). Inferior segment thicknesses were significantly thinner than the other segments (p?<?0.05). Subfoveal choroidal thickness and RNFL thickness measurements of the COPD group were also lower than those of the control group (p?=?0.111).

Conclusion: Hypoxia in COPD seems to affect the choroidal thickness. Thinning of the choroid may be attributed to increased vascular resistance and reduced blood flow in patients with COPD. The possible effects of the disease to the eye may be clarified through the role of the choroidal vasculature in the blood supply of the anterior optic nerve head.     

Ocular surface changes following botulinum toxin injection for strabismus

Context: Botulinum toxin injection is widely used for many purposes, including neuromuscular diseases, movement disorders and strabismus.

Objective: To evaluate and report the impact of botulinum toxin injection on ocular surface parameters in patients with strabismus.

Participants: Twenty-six consecutive patients who underwent botulinum toxin A injection for ocular misalignment were recruited for this prospective study.

Materials and methods: Testing of ocular surface parameters including tear break-up time (BUT), lissamine green (LG) staining and Schirmer test (under topical anesthesia) was performed, and Ocular Surface Disease Index (OSDI) questionnaire scores were recorded before and at certain time points after injection (one week, two weeks, one month, three months and six months after botulinum toxin A injection). Two-way analysis of variance (ANOVA) with repeated measures, Friedman’s test and Wilcoxon test were used for statistical analysis.

Results: Twenty six patients (15 eso- and 11 exo-deviations) with a mean age of 32.46?±?14.41 (17–65) years were recruited for the study. All injections were performed in one eye. The mean amount of deviation at near and distance reduced after injection. The change of BUT, LG staining and OSDI scores was found to be significant during follow-up in treated eyes (p?=?0.001, p?=?0.007 and p?=?0.009, respectively) whereas the change was insignificant for the Schirmer test results (p?=?0.266).

Conclusions: The ocular surface parameters appear to be altered by botulinum toxin injection in strabismic patients. Even though these effects seemed to be temporary, the findings of the present study support the notion of botulinum toxin effects on ocular surface parameters.     

The ocular surface side effects of an anti-psychotic drug,clozapine

Purpose: The purpose of this study is to investigate the effects of long-term clozapine usage on tear film stability and corneal topographic parameters.

Material and methods: The study was conducted between March 2014 and November 2014. Thirty patients who were diagnosed of schizophrenia and have been under clozapine treatment for 2.73?±?0.73 years (range 2–4 years) were involved in this study (group 1). Thirty healthy subjects (group 2) who have statistically similar demographic features compared with the group 1, were involved as a control group. Full ophthalmologic examination with biomicroscopy and indirect ophthalmoscopy was applied. Corneal topographic parameters were measured using the Pentacam HR and Schirmer test was done. Statistical analysis of the subjects was evaluated by using SPSS (for Windows version 16.0; SPSS Inc., Chicago, IL) program.

Results: K₁ value was measured as 43.39?±?0.17?D (43–43.50?D) and K₂ value was measured as 43.39?±?0.06?D (43.30–43.50?D) in groups 1 and 2, respectively. In groups 1 and 2, K₂ values were noted as 43.86?±?0.27?D (43.50–44.50?D) and 43.72?±?0.18?D (43.50–44.00?D), respectively. Central corneal thickness was found to be 523.93?±?15.66?µm (495–554?µm) and 550.13?±?1.03?µm (520–580?µm) in groups 1 and 2, respectively. Corneal apex thickness was 525.86?±?15.75?µm (497–556?µm) in group 1 and 551.60?±?14.99?µm (521–581?µm) in group 2. The corneal thickness of thinnest location was 520.93?±?15.60?µm (492–551?µm) and 548.06?±?15.17?µm (518–578?µm) in groups 1 and 2, respectively. Corneal volume was determined as 58.13?±?3.46?mm³ (52–64?mm³) in group 1 and 60.73?±?3.76?mm³ (54–66?mm³) in group 2. The Schirmer test showed thichkness of 3.33?±?0.72?mm (2–4?mm) and 13.60?±?1.59?mm (11–16?mm) in groups 1 and 2, respectively. The mean fluorescein break-up time was 5.40?±?1.50?s (3–8?s) and 12.46?±?1.40?s (10–14?s) in groups 1 and 2, respectively. There was a statistically significant difference in the Schirmer test, fluorescein break-up time, central corneal thickness, corneal apex, and the thinnest corneal location thickness between the two groups.

Conclusion: Clozapine may induce dry eye syndrome and thus may lead to morphological alterations in corneal parameters through its anticholinergic and antidopaminergic activities. Because of these corneal alterations, one should be aware of evaluating patients having diseases like glaucoma or preoperative selection of corneal refractive surgery candidates.     

Ocular surface findings in patients with rheumatoid arthritis under methotrexate or biological agent therapy

Purpose: To evaluate the ocular findings in patients with rheumatoid arthritis (RA) treated with disease-modifying antirheumatic drugs (DMARDs) such as methotrexate (MTX) or MTX with biological agents.

Methods: One hundred and twelve eyes of 56 patients with RA and treated with MTX or MTX with biological agents were included in the study. Patients were divided into two groups using DMARDs only (group 1) and patients using DMARDs and biologic agents together (group 2). In both groups; Schirmer’s II test, tear film break-up time (tBUT), central corneal thickness (CCT), corneal volume (CV), intraocular pressure (IOP) measurement, and anterior segment and fundus examinations of the eye with slit lamp were carried out. Ocular surface disease index (OSDI) score questionnaire were performed.

Results: Thirty-eight patients with a mean age of 53.00?±?8.19 years were in group 1 and 18 patients with a mean age of 51.00?±?9.54 years were in group 2. The mean duration of RA was 6.89?±?7.96 years in group 1 and 5.70?±?9.00 years in group 2. There was a statistically significant difference between two groups with tBUT, CCT, CV, IOP (p < 0.05) and there was no significant difference with age, sex, disease duration, disease activity, and Schirmer’s II test (p > 0.05). The disease duration showed a significant moderate negative correlation with CCT and CV in group 2 (p < 0.05).

Conclusions: Although tBUT values were significantly higher in the combination treatment group, CCT and CV values were significantly lower. Due to the decrease in corneal thickness, IOP was determined to be significantly lower.     

Evaluation of retinal nerve fiber layer thickness in vernal keratoconjunctivitis patients under long-term topical corticosteroid therapy

Purpose: The aim of this study was to evaluate the retinal nerve fiber layer (RNFL) thickness in vernal keratoconjunctivitis (VKC) patients who were under long-term topical corticosteroid therapy.

Methods: Thirty-six eyes of 36 VKC patients with clear cornea and normal videokeratography and 40 eyes of 40 age- and gender-matched normal children were included in the study. Clinical and demographic characteristics of the patients were noted and detailed ophthalmological examination was performed. Visual acuity (VA), spherical equivalent (SE), axial length (AL) and RNFL thickness measurements were compared between the groups. To correct ocular magnification effect on RNFL, we used Littmann’s formula.

Results: All VKC patients had history of topical corticosteroid use and the mean duration of the topical corticosteroid use was 23.8?±?9.09 months. There was no significant difference between the groups in terms of intraocular pressure (IOP). VKC group had significantly worse VA, greater SE and AL and thinner mean global, superior and inferior RNFL thickness. There were significant negative correlations between the duration of topical corticosteroid use and the mean global, superior and temporal RNFL thickness in VKC group. After correction of magnification effect, VKC group still had thinner mean global, superior and inferior RNFL thickness, and significant difference between the groups in inferior RNFL thickness did not disappear.

Conclusion: Significant RNFL thickness difference between the groups suggests a possible effect of long-term corticosteroid use in VKC patients. Because visual field (VF) analysis in pediatric patients is difficult to perform and IOP may be illusive, RNFL thickness measurements in addition to routine examinations in VKC patients may help clinicians in their practice.     

Pulmonary function and histological impairment in mice after acute exposure to aluminum dust

Along the aluminum refining process, alumina (Al₂O₃) constitutes the main source of dust. Although aluminum refinery workers present respiratory symptoms with lung functional changes, no conclusive data about lung function impairment after alumina exposure has been so far reported. We examined the pulmonary alterations of exposure to material collected in an aluminum refinery in Brazil. BALB/c mice were exposed in a whole-body chamber for 1?h to either saline (CTRL, n?=?11) or to a suspension (in saline) of 8?mg/m³ of the dust (ALUM, n?=?11) both delivered by an ultrasonic nebulizer. Twenty-four hours after exposure lung mechanics were measured by the end-inflation method. Lungs were prepared for histology. ALUM showed significantly higher static elastance (34.61?±?5.76 cmH₂O/mL), elastic component of viscoelasticity (8.16?±?1.20 cmH₂O/mL), pressure used to overcome the resistive component of viscoelasticity (1.62?±?0.24 cmH₂O), and total resistive pressure (2.21?±?0.49 cmH₂O) than CTRL (27.95?±?3.63 cmH₂O/mL, 6.12?±?0.99 cmH₂O/mL, 1.23?±?0.19 cmH₂O, and 1.68?±?0.23 cmH₂O, respectively). ALUM also presented significantly higher fraction area of alveolar collapse (69.7?±?1.2%) and influx of polymorphonuclear cells (27.5?±?1.1%) in lung parenchyma than CTRL (27.2?±?1.1% and 14.6?±?0.7%, respectively). The composition analysis of the particulate matter showed high concentrations of aluminum. For the first time it was demonstrated in an experimental model that an acute exposure to dust collected in an aluminum producing facility impaired lung mechanics that could be associated with inflammation.     

The protective effect of selenium in cisplatin-related retinotoxicity

Purpose: The aim of this study is to evaluate the retinal toxicity of cisplatin and neuroprotective effect of selenium in cisplatin-related retinal toxicity.

Methods: Eighteen adult Wistar-Albino rats were divided into three groups. Group 1 (n?=?6) received intraperitoneal (i.p.) injection of 2.5?ml physiologic saline for three days, group 2 (n?=?6) received i.p. 16?mg/kg cisplatin for three days and group 3 (n?=?6) received i.p. 16?mg/kg cisplatin for three days and 1.5?mg/kg twice daily selenium via gavage five days prior to cisplatin injection and for three days concomitantly with cisplatin injections. The total retinal thickness, outer nuclear layer (ONL), inner nuclear layer (INL) and inner plexiform layer (IPL) thicknesses were measured in hematoxylin/eosin and apoptotic index (AI) of ganglion cell layer (GCL) and INL was evaluated in TdT-mediated dUTP-biotin nick end labeling (TUNEL)-stained retina sections.

Results: Selenium statistically succeeded to reduce total retinal thickness in cisplatin-toxicated retinas: from 210.17?±?23.40 to 173.55?±?20.43, ONL: 49.79?±?5.32 to 41.87?±?6.30, INL: 33.72?±?7.93 to 25.06?±?5.73 and IPL: 53.61?±?8.63 to 45.61?±?6.92?µm in hematoxylin/eosin-stained retina sections. The AI was also reduced in INL (30.10?±?12.02 to 19.48?±?12.99) and in GCL (37.59?±?17.70 to 33.15?±?13.78). However, statistical significance was present in only AI values of INL.

Conclusions: Selenium limited edema due to the toxicity and reduced the retinal thickness and showed neuroprotection in cisplatin-induced retinotoxicity.     

The long-term effect of oral isotretinoin therapy on macula ganglion cell complex thickness

Purpose: To evaluate the long-term effect of oral isotretinoin therapy on macula ganglion cell complex (GCC) thickness by spectral domain optical coherence tomography (SD-OCT).

Materials and methods: Newly diagnosed cystic acne patients who received low dose for a long time systemic isotretinoin therapy were included in this study. Thorough ophthalmic evaluation and GCC thickness analysis by using SD-OCT were performed at baseline, and at 1, 3, 6, and 12 months of treatment.

Results: Forty-eight eyes of 24 patients (15 females, 9 males) were included in the study. The mean age of patients was 19.37?±?2.74 years (range 14–25 years). The full ophthalmologic examination was normal in all eyes before treatment. During the treatment there were no change in visual acuity, refractive error, intraocular pressure and tear break-up time. The mean GCC thicknesses were 81.45?±?4.91, 81.45?±?5.12, 81.81?±?4.68, 81.87?±?4.91 and 81.64?±?5.09?μm at pretreatment and at 1, 3, 6, and 12 months of treatment, respectively (p?=?0.803).

Conclusion: One-year systemic use of isotretinoin had no significant effect on the thickness of macula ganglion cell. Macular ganglion cell analysis is useful for determining and following the toxic effects of systemic drugs on the retina. However, it is more rational to consider it as an adjunct to electrophysiological testing rather than used alone.     

Metabolomic evaluation of Euphorbia pekinensis induced nephrotoxicity in rats

Context: Euphorbia pekinensis Rupr. (Euphorbiaceae) has long been used in the Orient, while its clinical use was limited due to its nephrotoxic effect.

Objective: The possible mechanism of nephrotoxicity of Euphorbia pekinensis (EPR) and its related constituents were investigated.

Materials and methods: Petroleum ether (PE), acetic ether (AE) and n-butanol (BUT) extracted sections of EPR were separately given to Wistar rats by gavage at the dose of 3?g/kg/day for 10 weeks to determine the nephrotoxic section of EPR. Then, renal metabolic profiling of EPR after oral administration of nephrotoxic section was investigated and its related constituents were identified by LC/Q-TOF-MS method.

Results: The average values of creatinine (CREA) in PE, AE, BUT and control groups were 76.54?±?9.52, 54.12?±?10.34, 51.33?±?5.19 and 48.23?±?6.67?μmol/L. The average values of blood urea nitrogen (BUN) in PE, AE, BUT and control groups were 15.25?±?3.37, 8.32?±?0.89, 9.22?±?1.78 and 8.47?±?1.33?mmol/L, respectively. Only kidney section of rats in PE group showed that glomeruli had cellular or fibrocellular crescents. Renal metabolic profiling showed disturbed metabolic pathways of purine, amino acid, phospholipids and sphingolipids in EPR nephrotoxicity. A total of 25 compounds [(–)-(1S)-15-hydroxy-18-carboxycembrene is a new compound] in PE section and 10 compounds in rat serum after administration of PE section were identified.

Conclusions: This is the first time that the toxic compounds of PER and action mechanism of EPR nephrotoxicity were explored to provide a new reference for studying the toxic components of Traditional Chinese Medicine (TCM).     

Assessment of ocular neurotoxicity in patients treated with systemic cancer chemotherapeutics

Purpose: Cisplatin and Paclitaxel are two chemotherapeutic agents known to produce neurotoxicity when used for cumulative dose regimens. In this study we aim to assess their toxicity in the optic nerve, and to evaluate the retinal nerve fibre layer (RNFL) thickness and visual field changes in lung cancer patients treated with Cisplatin and Paclitaxel.

Methods: Fifteen patients who were treated intravenously with 75?mg/m² cisplatin and 175?mg/m² paclitaxel every 3 weeks, up to a maximum of six courses, were enrolled in this prospective clinical trial. All patients underwent complete ophthalmological assessments before their treatments began, as well as three months after the completion of their treatments. The RNFL thickness measurements were performed using optical coherence tomography (OCT). Functional testing included the use of frequency-doubling technology (FDT) perimetry and the Humphrey visual field analyser (HFA). The main outcome measurements included the average RNFL thicknesses and visual field indices (mean deviation [MD] and pattern standard deviation [PSD]).

Results: The median age of the 15 patients (nine male and six female) was 63.49 years old (range: 53–77). The average RNFL thickness measurement during the baseline examination was 103.73?μm (range: 97–111). Three months after the cessation of treatment the RNFL thickness declined to 97.4?μm (range: 91–102). Statistical analysis showed a significant thinning between the two measurements (p?=?0.032). The MD and PSD values recorded by the HFA demonstrated no statistically significant changes 3 months after the cessation of treatment (p?>?0.207 and p?>?0.186, respectively). There were statistically significant decreases in both the MD (0.48 to ?1.13?dB) and PSD (2.13 to 0.65?dB) indices measured by the FDT perimetry (p?=?0.041 and p?=?0.025, respectively).

Conclusions: In our study, the systemic administration of Cisplatin and Paclitaxel affected the peripapillary RNFL thicknesses and visual field indices as revealed by FDT perimetry. OCT and FDT perimetry may be adjunctive tools for the screening of ocular toxicity in patients treated with these agents.