Follow up of retinal nerve fiber layer thickness with optic coherence tomography in patients receiving anti-tubercular treatment may reveal early optic neuropathy

Purpose: To evaluate the effect of anti-tubercular treatment on retinal nerve fiber layer (RNFL) thickness and the efficiency of optic coherence tomography (OCT) on early diagnosis of optic neuropathy.

Methods: Twenty patients diagnosed with either pulmonary or extra-pulmonary tuberculosis which were treated with anti-tubercular treatment (isoniazid (INH), rifampicin, ethambutol (ETM), and pyrazinamide) were enrolled in the study. RNFL thicknesses of the patients were measured via OCT, at baseline (before starting anti-tubercular treatment) and after the two-month treatment period. Standard ophthalmologic examinations were also performed.

Results: Compared to baseline values, after the two-month treatment period, thinning was detected in the right eye’s average and superior quadrant RNFLs (p?=?0.024 and p?=?0.006 respectively) and in the left eye’s average, superior quadrant, and inferior quadrant RNFLs (p?=?0.001, p?=?0.008, p?Conclusion: We displayed that patients receiving INH and ETM, which were the basic medicines of anti-tubercular treatment, experienced thinning in RNFL after the two-month treatment period. Patients receiving these drugs can be followed via OCT in terms of reduction in RNFL thicknesses for early diagnose of INH and ETM toxicity.     

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.     

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.     

The effect of cigarette smoking on retinal nerve fiber layer thickness in patients with migraine

Context: Migraine is a frequent and disabling chronic neurological condition with complex pathophysiology. Both cigarette smoking and migraine may cause damage to the optic nerve. Objective: The primary objective of this study was to investigate the effect of cigarette smoking on retinal nerve fiber layer (RNFL) thickness in patients with migraine.

Materials and methods: Eighty-four consecutive patients diagnosed with migraine (34 smokers and 50 nonsmokers) and 66 age- and gender-matched healthy non-smoker controls were enrolled for this observational cross-sectional study. RNFL thickness was measured using spectral-domain optical coherence tomography (OCT) and then RNFL thickness in patients with migraine who smoke was compared to nonsmoking patients with migraine and healthy subjects.

Results: The average, superior, nasal and inferior RNFL thicknesses were significantly thinner in patients with migraine compared to the control group (p?<?0.001, p?=?0.02, p?<?0.001 and p?=?0.04, respectively). The average and inferior RNFL thicknesses were significantly reduced in smoker patients with migraine compared to the nonsmokers (p?=?0.011, p?=?0.045, respectively). Nonsmoker patients with migraine had significantly thinner average and nasal RNFL thicknesses than the control group (p?=?0.001, p?=?0.001, respectively).

Conclusion: Cigarette smoking may cause significant RNFL thinning in patients with migraine. OCT may be a feasible technique for determination of smoking-induced ocular damage in patients with migraine.     

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.     

Assessment of macular choroidal thickness,central macular thickness and retinal nerve fiber layer in patients receiving oral isotretinoin treatment

Abstract

Purpose

To investigate the impact of oral isotretinoin therapy in choroidal thickness, central macular thickness (CMT), and retinal nerve fibre layer (RNFL) thickness using optical coherence tomography (OCT).     

Ocular findings in coal miners diagnosed with pneumoconiosis

Objective: Our study aimed at evaluating ocular findings and structural changes in coal mine workers who were chronically exposed to coal mine dust and diagnosed with pneumoconiosis.

Methods: Ocular findings of 161 eyes of 81 patients diagnosed with pneumoconiosis who had previously worked or are currently working in coal mines were analyzed. Forty-six coal mine workers and sex matched healthy people (n?=?20) participated in the study. Workers who had early changes of pneumoconiosis were included in Group 1 (n?=?17), workers diagnosed with pneumoconiosis were included in Group 2 (n?=?29), and healthy subjects were included in Group 3 (n?=?20). Outcome measures were the difference in peripapillary retinal nerve fiber layer (RNFL) thickness, choroidal thickness (CT), central macular thickness (CMT) and tear function tests between the groups.

Results: RNFL thickness values in Group 1 and 2 were lower than in Group 3, the control group, in all quadrants except the temporal quadrant. However, there was no statistically significant difference in peripapillary RNFL thickness values in any quadrants among the three groups (p?>?0.05). Central subfoveal choroidal thickness and CMT measurements were thinner in Group 1 and 2 than in the control group. However, this difference among groups was not statistically significant (p?>?0.05). Mean schirmer's test result was 8.8?±?1.6?mm in group 1, 7.1?±?1.8?mm in Group 2 and 11.5?±?3.6?mm in the control group. Mean tear break up time (BUT) test result was 7.1?±?1.3?seconds (sec) in Group 1, 6.5?±?1.8?sec in Group 2 and 10.4?±?2.9?s in the control group. The Schirmer's test and BUT test results were both statistically significantly lower in coal mine workers (Group 1 and 2) compared to the control group. Group 1 and Group 2 did not show statistically significant difference in terms of Schirmer's test and BUT test results.

Discussion: The association between pneumoconiosis and coal mine dust contiguity is thought to be due to the effect of coal dust by producing chronic inflammation. In addition, there are several trace elements in coal dust which are toxic to vital tissues. In this study, ocular findings suggest that systemic levels of trace elements and chronic inflammation may not reach to a level that influences ocular structures. Nonetheless, tear functions seem to be affected in coal mine workers.

Conclusion: This study suggests that the systemic effect of coal mine dust in ocular structures is not evident. However, direct contact with coal mine and fume leads to a decrease in tear function tests.     

Retinal structural changes in patients receiving tamoxifen therapy by spectral-domain optical coherence tomography

Abstract

Purpose: To evaluate choroidal thickness, ganglion cell complex (GCC) and photoreceptor outer segment (PROS) length were measured in patients with breast cancer undergoing tamoxifen therapy, using spectral-domain optical coherence tomography (SD-OCT); results were compared with those for normal eyes.

Materials and methods: Forty-four patients with breast cancer, undergoing tamoxifen therapy, and 41 healthy controls were included in this prospective, comparative study. All participants underwent a complete ophthalmologic evaluation and SD-OCT. Subfoveal, nasal (nasal distance to fovea 500, 1000, 1500?μm), and temporal (temporal distance to fovea 500, 1000, 1500?μm) choroidal thickness measurements were performed using the enhanced depth imaging mode of SD-OCT. Using an Early Treatment Diagnostic Retinopathy Study (ETDRS) circle at the macular level, the automated retinal segmentation software was applied to determine the thickness of the GCC. PROS length was determined manually, as the distance from the inner surface of the ellipsoid zone to the inner surface of retina pigment epithelium.

Results: The mean choroidal thickness was statistically greater in the tamoxifen group than controls in all quadrants (p?<?0.001 for all quadrants). Of all tamoxifen users (44 eyes of 44 patients), 33 eyes (75%) had uncomplicated pachychoroid (UCP). Pachychoroid pigment epitheliopathy (PPE) was detected in five tamoxifen-group patients (11.3%). Patients with PPE in one eye had UCP in the fellow eye. Central serous chorioretinopathy findings were observed in one patient. Tamoxifen users had statistically lower GCC thickness in all inner rings of the ETDRS inlay and in the nasal outer ring only (p?=?0.027, 0.002, 0.002, 0.001, and 0.030, respectively). No statistically significant difference in mean subfoveal PROS length was found between the groups.

Conclusions: SD-OCT provides valuable information for identifying structural changes and evaluating ocular findings in patients receiving tamoxifen therapy. Increased choroidal thickness, PPE and thinning GCC were detected in tamoxifen users. These OCT findings may be an early indicator of retinal toxicity for patients undergoing tamoxifen therapy in the follow-up period.     

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.     

近视眼神经纤维层厚度光学相干断层扫描分析

目的研究人视网膜神经纤维层(RNFL)厚度随近视眼屈光度加深而变化的特点及临床意义。方法将近视眼108例(197眼)和正常对照者42例(60眼)分为低度近视组、中度近视组、高度近视组和正常对照组,应用光学相干断层扫描仪(OCT)进行以视乳头为中心,直径3．46mm圆周的RNFL厚度测量,计算各组平均RNFL厚度及鼻、颞、上、下四个象限的RNFL厚度,各近视组分别与正常组对比,并进行统计学分析。结果低度、中度近视眼平均神经纤维层厚度变薄但与正常对照无显著性差异(P＞0．05),高度近视眼平均神经纤维层厚度明显变薄,与正常对照相比具有显著性差异(P＜0．01)。近视眼各象限RNFL最早变薄的是鼻象限,低度近视即与正常人有显著性差异(P＜0．01)。高度近视跟鼻、下、上象限RNFL均明显变薄(P＜0．01),而颞象限RNFL反而增厚,与正常人相比有显著性差异(P＜0．01)。结论近视眼平均RNFL厚度呈变薄的改变,随着近视度数的加深,近视跟RNFL厚度变薄越来越明显。分区分析上、下、鼻象限变化与平均相一致,而颞象限增厚,这可能是近视眼RNFL的特点。这些特点对临床疾病的诊断具指导意义。     

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.     

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.     

Ocular effects of pegylated interferon-α in patients with chronic hepatitis B

Abstract

Purpose: To evaluate the early retinal changes and its reflection on the visual field examination in chronic hepatitis B (CHB) patients using pegylated interferon-α (PEGIFN-α) monotherapy.

Patients and methods: Thirty eyes of fifteen patients with CHB were examined prospectively for changes in the fundus examination and visual field examination (both Humphrey Perimetry and Frequency Doubling Perimetry). The patients were examined before and in 3 months intervals after starting the PEGIFN-α treatment. The changes in the fundus examination were noted and the visual field examinations, retinal nerve fiber thickness, Schirmer scores and color vision before and at 3 months of the treatment were compared. The statistical evaluation was performed with paired-t test, using SPSS 16.0 Inc. (Chicago, IL).

Results: The mean age of the 15 patients (seven male, eight female) was 52.5?±?12.4 years. There was no significant retinal change in none of the patients. Neither the visual field examination with Humphrey Field Analyzer nor the Frequency Doubling Perimetry results has demonstrated any significant change during 3 months follow-up. There was a statistically significant increase in the retinal nerve fiber layer (RNFL) thickness; while Schirmer test scores for dry eye assessment was significantly decreased.

Conclusion: PEGIFN-α monotherapy, which is used for treatment of CHB, may cause some changes in the thickness of RNFL that may necessitate the close follow-up for further morphological changes of the optic disc in these patients.     

Electroretinographic and optical coherence tomography findings in breast cancer patients using aromatase inhibitors

Background: The present cross-sectional study has the purpose to investigate the impact of aromatase inhibitors (AIs) on retinal nerve fiber layer (RNFL) thickness, optic nerve and macular function in patients using AIs for breast cancer treatment.

Methods: Participants in our study were 41 hormone-receptor-positive earlystage breast cancer patients who were treated with AIs in the adjuvant setting. Moreover, 40 age- and gender-matched control subjects, having neither ocular nor systemic disorders, were included in this study. All participants underwent a complete ophthalmological examination, including best corrected visual acuity (BCVA) assessment, RNFL thickness and central foveal thickness (CFT) measurement, visual evoked potentials (VEP) recording and multifocal-electroretinogram (mf-ERG) recording. Univariate and multiple regression analyses were performed.

Results: At the multiple regression analyses, patients receiving AIs presented with lower average RNFL and inferior RNFL. Moreover, similarly to the univariate analysis, intake of AIs was associated with lower amplitude P100, lower retinal response density in ring 1 and ring 2, longer peak time P100 and longer P1 time in ring 1.

Conclusion: Our study is the first in the literature investigating the potential effect of AIs on RNFL thickness, optic nerve and macular function in patients using AIs for breast cancer treatment. The principal message of our study is that patients using AIs exhibited a significant decrease in RNFL thickness (average, superior and inferior), retinal response density and visual acuity compared to healthy controls, while VEP findings (both amplitude and peak time of P100) differ significantly as well.     

Retrospective analysis of the effect of aflibercept loading dose on the retinal vessel diameters in patients with treatment-naive neovascular AMD*

Background: To evaluate the effects of intravitreal aflibercept (IVA) on retinal vessel diameters in patients with neovascular age-related macular degeneration (AMD).

Design, setting, and participants: A retrospective study conducted at the Kutahya Dumlupinar University Faculty of Medicine included 15 eyes of 15 patients with treatment naive neovascular AMD.

Methods: All eyes received IVA injections once per month for 3?months; untreated contralateral eyes were used as controls. The central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery-vein ratio (AVR) values were measured using a computer-based program before the first IVA injection and 30?days after the first, second, and third injections. The main outcome measurements were the central macular thickness (CMT), best-corrected visual acuity (BCVA), choroidal thickness, CRAE, CRVE, and AVR.

Results: Significant vasoconstriction of the retinal arterioles was observed in all eyes treated with IVA when compared to baseline (p?=?0.009). However, no significant differences were found for CRVE or AVR throughout the study period in treated eyes. In the control group, all parameters measured during each visit were similar to baseline measurements (p?>?0.05). The mean BCVA significantly improved at the end of the loading dose of IVA, when compared to baseline (p?=?0.006). After the IVA injections, the mean CMT and choroidal thickness were significantly reduced at all visits, compared to baseline (p?Conclusions: The current study showed that IVA led to significant retinal arteriolar vasoconstriction and choroidal thinning, which may cause reduced retinal blood flow.     

Effect of intracameral carbachol in phacoemulsification surgery on macular morphology and retinal vessel caliber

Objective: To investigate the effects of intracameral carbachol in phacoemulsification surgery on central macular thickness (CMT), total macular volume (TMV) and retinal vessel caliber (RVC).

Materials and methods: In this prospective consecutive case series, 82 patients underwent uneventful phacoemulsification and in-the-bag intraocular lens implantation. Unlike patients in the control group (43 eyes), patients in the study group (42 eyes) were injected with intracameral 0.01% carbachol during surgery. Spectral-domain optical coherence tomography (OCT) was used to analyze the parameters of CMT, TMV and RVC.

Results: On the first postoperative day, mean CMT and TMV decreased markedly in the carbachol group, though these values did not change significantly in the control group. During follow-up visits, no statistically significant differences between the groups occurred regarding changes in mean CMT (p?=?0.25, first day; p?=?0.80, first week; p?=?0.95, first month). However, change in mean TMV between groups on the first postoperative day was statistically significant (p?=?0.01, first day; p?=?0.96, first week; p?=?0.68, first month). RVC values were similar on the preoperative and postoperative first days in both groups (p?>?0.05).

Discussion: Results suggest that the effect of intracameral carbachol on macular OCT is related to pharmacological effects, as well as optic events (e.g. miosis).

Conclusion: Intracameral carbachol given during cataract surgery decreases macular thickness and volume in the early postoperative period but does not exert any gross effect on RVC.     

Retinal ganglion cell complex and visual evoked potentials in levetiracetam treatment

Abstract

Purpose

To examine central macular, RNFL (retinal nerve fibre layer), GCC (ganglion cell complex) thicknesses; and VEPs (visual evoked potential) in epileptic patients using levetiracetam for at least one year.     

The effectiveness and reliability of posterior sub-Tenon triamcinolone acetonide injection in branch retinal vein occlusion-related macular edema

Objective: To investigate the effectiveness and reliability of posterior sub-Tenon triamcinolone acetonide (PSTA) application in branch retinal vein occlusion (BRVO)-related macular edema.

Methods: Patients with confirmed BRVO-related macular edema were enrolled in the study. Patients were injected with a single, therapeutic dose of 40?mg PSTA. Detailed ophthalmic examination was performed at baseline and at 1, 3 and 6 months after the treatment. Best corrected visual acuity (BCVA), intraocular pressure (IOP), cataractogenic change (CC) and macular optical coherence tomography (OCT) analysis results were evaluated. The results were compared statistically.

Results: Forty-one eyes of 41 patients with a mean age of 63.49?±?10.99 (55–86) years, 15 (36.6%) females, were included in the study. BCVA in LogMAR values at 1 and 3 months were significantly better than at baseline, while no significant difference from baseline was observed in sixth month values (p?<?0.001, p?<?0.001 and p?=?0.846, respectively). Central macular thickness values obtained using OCT were significantly lower at the first, third and sixth months compared to baseline (p?<?0.001 for all). IOP elevation was determined in only two eyes (4.8%) at the end of the study period, and no CC was detected in any case.

Conclusion: PSTA application is an effective and safe option in BRVO-related macular edema.     

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.     

Visual function test for early detection of ethambutol induced ocular toxicity at the subclinical level

Context: Tuberculosis in developed countries is on the rise, and the main treatment ethambutol is known to induce ocular toxicity. However, to date, there are unknown tests or protocols for detecting subclinical ethambutol-induced ocular toxicity, which is important as early detection is related to symptom reversibility. We defined the ethambutol induced ocular toxicity as stastically siginificant change of visual function which was induced by ethambutol.

Objective: We aimed to identify a visual function test for the early detection of subclinical ethambutol-induced ocular toxicity. Furthermore, we also investigated the continuity or reversibility of early subclinical changes that were observed during the visual function tests after stopping ethambutol treatment.

Materials and methods: The age range of 31 patients was from 13 to 72 years. The range of dosage was 15–19?mg/kg/day. The average period of dosage was 5 months. We performed a visual acuity test, visual field test, color vision test, contrast sensitivity test, fundus examination, retinal nerve fiver layer optical coherence tomography test (RNFL OCT) per month and pattern visual evoked potential test (pattern VEP) every 2 months before and during ethambutol treatment in 62 eyes of 31 patients. Among these patients, selected 21 patients were rexamined by these tests at the 3, 6 and 12 months after stopping ethambutol treatment. We compared the test results from the last follow-up during ethambutol treatment and after ethambutol stoppage with those obtained before ethambutol treatment (baseline).

Results: RNFL OCT showed that average RNFL thickness increased 5 months after ethambutol treatment (p?=?0.032), and pattern VEP showed that P100 latency was delayed in 2 and 4 months after ethambutol treatment (p?=?0.001; p?<?0.001, respectively). These early changes observed on RNFL OCT and pattern VEP progressed 6 months after ethambutol stoppage in 21 patients. Twelve months after ethambutol stoppage, these early changes returned to baseline levels. During the study, no changes in visual acuity, color vision, fundus, contrast sensitivity or visual field were observed.

Conclusions: Pattern VEP and RNFL OCT are suitable tests for the early detection of subclinical ethambutol-induced ocular toxicity. These tests should be performed until 12 months after ethambutol stoppage.