Optical Coherence Tomography Exam Research Articles

Improved predictive diagnosis of diabetic macular edema based on hybrid models: An observational study

Diabetic Macular Edema (DME) is the most common sight-threatening complication of type 2 diabetes. Optical Coherence Tomography (OCT) is the most useful imaging technique to diagnose, follow up, and evaluate treatments for DME. However, OCT exam and devices are expensive and unavailable in all clinics in low- and middle-income countries. Our primary goal was therefore to develop an alternative method to OCT for DME diagnosis by introducing spectral information derived from spontaneous electroretinogram (ERG) signals as a single input or combined with fundus that is much more widespread. Baseline ERGs were recorded in 233 patients and transformed into scalograms and spectrograms via Wavelet and Fourier transforms, respectively. Using transfer learning, distinct Convolutional Neural Networks (CNN) were trained as classifiers for DME using OCT, scalogram, spectrogram, and eye fundus images. Input data were randomly split into training and test sets with a proportion of 80 %–20 %, respectively. The top performers for each input type were selected, OpticNet-71 for OCT, DenseNet-201 for eye fundus, and non-evoked ERG-derived scalograms, to generate a combined model by assigning different weights for each of the selected models. Model validation was performed using a dataset alien to the training phase of the models. None of the models powered by mock ERG-derived input performed well. In contrast, hybrid models showed better results, in particular, the model powered by eye fundus combined with mock ERG-derived information with a 91 % AUC and 86 % F1-score, and the model powered by OCT and mock ERG-derived scalogram images with a 93 % AUC and 89 % F1-score. These data show that the spontaneous ERG-derived input adds predictive value to the fundus- and OCT-based models to diagnose DME, except for the sensitivity of the OCT model which remains the same. The inclusion of mock ERG signals, which have recently been shown to take only 5 min to record in daylight conditions, therefore represents a potential improvement over existing OCT-based models, as well as a reliable and cost-effective alternative when combined with the fundus, especially in underserved areas, to predict DME.

Effect of blood pressure variability on hypertensive retinopathy

ABSTRACT Purpose This study intends to investigate the correlation between blood pressure variability (BPV) levels and the use of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) to measure retinal microvasculature in hypertensive patients. Methods All individuals in the study had 24-hour ambulatory blood pressure monitoring and bilateral OCT and OCTA exams, and only data from the right eye were analyzed statistically. Results The study included 170 individuals, with 60 in the control group. The experimental group was separated into two groups based on the average real variability (ARV) median, with 55 in the low ARV group and 55 in the high ARV group. The mean thicknesses of the Retinal Nerve Fiber Layer (RNFL), internal limiting membrane-retinal pigment epithelial cell layer (ILM-RPE), vessel density (VD), and perfusion density (PD) in the high-ARV group were substantially lower in the low-ARV and control groups (p＜0.05). Multiple linear regression analysis revealed that disease duration, age, and 24 h diastolic standard deviation all affected RNFL mean thickness (p＜0.05). VD and PD were influenced by disease duration, systolic-ARV, daytime systolic blood pressure, intraocular pressure(IOP), and best-corrected visual acuity (BCVA) (p＜0.05). And the change in VD was connected to best-corrected visual acuity. Conclusion Hypertensive retinopathy is related to BPV. In clinical practice, we can assess the degree of BPV and retinopathy in hypertensive patients to track the progression of hypertension-mediated organ damage (HMOD). Correction of BPV may help treat or postpone the progression of HOMD.

From Photophobia to Achromatopsia. How to Establish the Correct Diagnosis

Achromatopsia is a congenital autosomal recessive disorder characterized by decreased or absent cone’s function. Clinical symptoms include photophobia, nystagmus, low best corrected visual acuity, complete or incomplete color vision. Mutations in the CNGA3 and CNGB3 genes are responsible for approximately 70–80 % of all achromatopsia cases. The purpose: to evaluate the results of a comprehensive clinical and genetic examinations of four patients with an established diagnosis of achromatopsia. Onset of the disease in all patients was in the form of severe photophobia and nystagmus, appearing at the age from 1.5 to 11 months. According to optical coherence tomography exams were detected structural changes in neuroepithelium (three patients), varied from subfoveal disorganization of the photoreceptor outer segments with “blurring” of the external limiting membrane line and ellipsoid zone to subfoveal destruction of the photoreceptor outer segments and the presence of a slit defect. Out of seven identified mutations in the CNGA3 and CNGB3 genes, two were previously detected in Russian patients, and five were not detected in the Russian Federation.

Border tissue morphology is associated with macular ganglion cell thickness in open-angle glaucoma

Externally oblique border tissue (EOBT) configuration is topographically associated with glaucomatous damage in the optic nerve head. We investigated the relationship between the EOBT characteristics and macular retinal ganglion cell (RGC) thickness in patients with open-angle glaucoma (OAG). A total of 149 eyes with OAG that had an EOBT observed on optical coherence tomography exams were included. After determining the maximum EOBT length and angular location of the maximal EOBT length, we analyzed their correlation with macular ganglion cell inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thickness. The macular GCIPL and pRNFL thickness were compared based on the angular location of the longest EOBT, and their association was assessed using multivariable regression analysis. Maximum EOBT length was significantly correlated with macular GCIPL thickness, but not with pRNFL thickness. Macular GCIPL was thinnest in eyes with EOBT located in a temporal direction to the optic disc. Longer maximum EOBT and temporally elongated EOBT were independently associated with a thinner macular GCIPL in the multivariable regression analysis. These suggest that temporal elongation of the EOBT may increase the stress and strain on the RGCs derived from the macula and make RGCs more susceptible to glaucoma-inducing damage.

Proteinuria in early referral to spectral domain optical coherence tomography for macular edema detection in type 2 diabetes individuals: results from the Brazilian diabetes study

Background Measurement of retinal thickness by optical coherence tomography (OCT) shows higher diagnostic accuracy for diabetic macular edema (DME) than fundus photography alone. The expanding gap between the rising number of type 2 diabetes (T2D) individuals and the availability of OCT devices demands a targeted selection of individuals at higher risk of DME who would benefit the most from early referral. We sought to appraise if proteinuria should be considered in a targeted referral of T2D individuals to OCT examination. Methods This study was a cross-sectional analysis of 576 consecutive patients enrolled in the Brazilian Diabetes Study between June/2016 and December/2021 who underwent OCT exam and urinalysis to assess ME and proteinuria status, respectively. Differences in the prevalence of DME between proteinuria groups and across a range of diabetic retinopathy (DR) stages were evaluated. Results Among 1134 eyes included in this analysis, the prevalence of proteinuria was 22% and 18.2% of eyes had DME. Proteinuria was related to an increased prevalence of DME (13.2% vs 38.7% for control vs proteinuria, respectively; p < .001), with an OR of 4.08 [95% confidence interval (CI): 2.50–6.64, p < .001), after adjustment for covariates. Proteinuria was independently related to DME also among eyes with non-apparent DR [OR: 2.82; 95%CI: 1.34–5.93; p = .003] and non-proliferative DR (OR of 5.94, 95%CI 2.13–16.62, p < .001). Fundus photography spotted only half of the DME cases detected by OCT. Conclusion In T2D individuals, early referral to OCT examination should be pursued for all individuals with concurrent proteinuria. Trial registration ClinicalTrials.gov Identifier: NCT04949152

Peripapillary retinal nerve fiber layer thinning in patients with progressive supranuclear palsy

ObjectivesTo investigate peripapillary retinal nerve fiber layer (pRNFL) changes in patients with progressive supranuclear palsy (PSP).MethodsWe included 21 PSP patients (36 eyes) who underwent peripapillary optical coherence tomography (OCT) scans at 2.5 ± 1.3 years of disease, without ophthalmologic co-morbidities. We compared pRNFL thicknesses in PSP eyes with age-matched 22 controls (22 eyes) using generalized estimating equation model adjusting for intra-subject inter-eye correlations, age and sex. We also analyzed the correlation between the pRNFL thickness and clinical severity using Spearman’s correlation. In twelve PSP patients with 3 T brain MRI volumetric scan within 1 year of OCT exam, we investigated the correlation between the pRNFL thickness and brain atrophy using Pearson’s correlation.ResultsPSP patients had global pRNFL thinning compared to controls (beta = − 6.436, p = 0.025). Global pRNFL thickness correlated with Hoehn & Yahr stages (r = − 0.487, p = 0.025), and nasal pRNFL thinning showed a trend of correlation (uncorrected p < 0.05). Exploratory correlation analysis between global pRNFL thickness and nonmotor items in the PSP rating scale showed a trend toward association with sleep disturbances (uncorrected p = 0.008) and urinary incontinence (uncorrected p = 0.031), although not significant after Bonferroni correction (all 28 items). The patients had significant atrophy in the posterior cingulate cortex, third ventricle, pallidum, and midbrain with reduced midbrain-to-pons ratio, but no correlation was found between pRNFL thickness and brain volumes.ConclusionThe pRNFL seems to be affected in PSP, which is more severe with advanced disease stages. Retinal investigation in a larger longitudinal cohort would help elucidate the pathophysiological role of retinal thinning in PSP.

Clinical effects associated with five-year retinal nerve fiber layer thinning in multiple sclerosis

BackgroundNeurodegenerative changes in multiple sclerosis (MS) are associated with long-term disability progression (DP). Optical coherence tomography (OCT) measures may be used to monitor DP. ObjectiveTo determine significant effects driving the changes in OCT-based peripapillary retinal nerve fiber layer (pRNFL) in heterogeneous group of MS patients. MethodsTotal of 144 MS patients (109 relapsing-remitting MS and 35 progressive MS (PMS) with mean age at baseline of 47.6 and 56.5 years old, respectively) underwent clinical and OCT examination over 5-year follow-up. All OCT exams were reviewed using the OSCAR-IB criteria. The 5-year DP was determined based on Expanded Disability Status Scale (EDSS) changes and MS clinical trial criteria. Data regarding previous history of MS optic neuritis (MSON) and use of disease modifying treatment (DMT) was derived by in-person interview and review of electronic medical records. Mixed model-type of repeated measure analysis determined effects driving pRNFL change for analysis which utilized all eyes separately. ResultsOver an average of 5.3-years follow-up, the MS population demonstrated significant pRNFL thinning (F = 16.108, p < 0.001). The pRNFL thinning was greater due to progressive MS subtype (F = 5.102, p = 0.025), greater age at baseline (F = 4.554, p = 0.034), occurrence of DP (F = 6.583, p = 0.011), and previous history of MSON (F = 7.053, p = 0.008). Use of any or highly potent DMT (natalizumab versus first-line injectable treatments versus no DMT) significantly reduced the pRNFL thinning (F = 8.367, p = 0.004) over the follow-up. Lastly, occurrence of DP in PMS patients older than 50 years old was associated with greater pRNFL thinning (F = 6.667, p = 0.013). ConclusionLongitudinal pRNFL changes are modified by age, disease subtype, disabiltiy progression, history of MSON, DMT use and their interactions.

Bartonella hanselae retinitis patient evaluated with multimodal retinal exams

BackgroundCat scratch disease is a systemic infectious illness caused by the bacterium Bartonella henselae. The most common ophthalmological involvement due to infection by Bartonella is Parinaud oculoglandular syndrome, whereas the most common posterior segment findings are neuroretinitis and subsequent late macular star. Moreover, other findings, such as retinal or subretinal lesions, intermediate uveitis and angiomatous lesions, may be present.Case presentationA 37-year-old female patient with retinal findings and serological confirmation of Bartonella infection was evaluated via multimodal retinal exams. The patient received treatment with doxycycline 100 mg twice daily for 2 weeks. One month after treatment, complete improvement of her visual scotoma symptoms was confirmed. A swept-source optical coherence tomography exam also showed decreases in the size and intraretinal extension of the lesion. Improvement of light perception at the affected area was confirmed by microperimetry.ConclusionsBartonella henselae infection, particularly retinitis, can present a variable spectrum of clinical and ophthalmological findings. Multimodal retinal exams can clearly identify lesion characteristics, thus providing important information for diagnosis and the evaluation of lesion improvement after antibiotic treatment.

Peripapillary Retinal Vascular Involvement in Early Post-COVID-19 Patients

The ability of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2′s) to cause multi-organ ischemia and coronavirus-induced posterior segment eye diseases in mammals gave concern about potential sight-threatening ischemia in post coronavirus disease 2019 patients. The radial peripapillary capillary plexus (RPCP) is a sensitive target due to the important role in the vascular supply of the peripapillary retinal nerve fiber layer (RNFL). Eighty patients one month after SARS-CoV-2 infection and 30 healthy patients were selected to undergo structural OCT (optical coherence tomography) and OCTA (optical coherence tomography angiography) exams. Primary outcome was a difference in RPCP perfusion density (RPCP-PD) and RPCP flow index (RPCP-FI). No significant difference was observed in age, sex, intraocular pressure (IOP) and prevalence of myopia. RPCP-PD was lower in post SARS-CoV-2 patients compared to controls. Within the post-COVID-19 group, patients with systemic arterial hypertension had lower RPCP-FI and age was inversely correlated to both RPCP-FI and RPCP-PD. Patients treated with lopinavir + ritonavir or antiplatelet therapy during admission had lower RPCP-FI and RPCP-PD. RNFL average thickness was linearly correlated to RPCP-FI and RPCP-PD within post-COVID-19 group. Future studies will be needed to address the hypothesis of a microvascular retinal impairment in individuals who recovered from SARS-CoV-2 infection.

The new Myopic Traction Maculopathy Staging System.

To describe a comprehensive OCT-based classification of myopic traction maculopathy (MTM). Two hundred eighty-one eyes with MTM (visited from 2006 to 2018), were retrospectively reviewed for age, best-corrected-visual-acuity (BCVA), axial length (AL), optical coherence tomography (OCT), and wide-field color fundus-photographs. The study was divided in two Phases. Phase 1: MTM types were categorized with OCT and correlated with age and BCVA. The type of staphyloma was described. Phase 2: the evolution of MTM was studied evaluating at least three OCT exams of each eye taken at different timings (interval between each exam: 1-10 years). Phase 1: We identified, four MTM retinal stages (1. Inner/Outer Maculoschisis; 2. Predominantly outer Maculoschisis; 3. Maculoschisis-Macular Detachment; 4. Macular Detachment) and three foveal stages (a. Normal fovea; b. Inner Lamellar-Macular-Hole; c. Full-Thickness-Macular-Hole). Outer-Lamellar-Macular-Holes and epiretinal abnormalities were associated findings. Stages 1 to 2 were younger than stages 3 to 4 (p < 0.05). BCVA in stages 1, 2 was similar, and higher than stages 3, 4 (p < 0.02). About 14% of eyes had no staphyloma, 73% of eyes had staphyloma type 1 or 2. MTM stages were not correlated with AL. Phase 2: The retina could change in time from stage 1 to 4, or the fovea could change from stage a to c. Mean evolution time from stage 1 to 2, stage 2 to 3, and 3 to 4 were 20, 12, 3 months, respectively. BCVA decreased over time as stages increased (p = 0.47). The MSS Table displays a new classification, the natural evolution, and practical insights for the management of MTM.

Caracterización de indicadores de detección de glaucoma con los equipos OCT Spectralis y campímetro Humphrey II en pacientes altos miopes y altos miopes glaucomatosos del Hospital Clínico Universidad de Chile

Purpose: Characterize and describe glaucoma index parameters of the results of visual exams,&#x0D; Optical Coherence Tomography and Visual Field, in high myopic subjects with and without the&#x0D; pathology. Method: Cross sectional and observational study of 39 eyes, 15 high myopic with&#x0D; glaucoma y 24 high myopic without it. Visual Field (VF) were performed, where the global&#x0D; index between both groups were analyzed; Mean Deviation (MD), Model Standard Deviation&#x0D; (MSD) and Visual Field Index (VFI), beside Optical Coherence Tomography (OCT), in which the&#x0D; thickness of the ganglion cells layer (GCL) inside 3 central mm was compared. Results: The&#x0D; results were satisfactory, demonstrating different characteristics between the high myopic&#x0D; group with glaucoma and without it, both in VF and OCT exams. It was obtained in the VF&#x0D; analysis difference in average MD of -4,92 dB + 3,71 (p0,05) and VFI with Friedman Test 10,29 (p&gt;0,05). The statistical OCT&#x0D; analysis, when comparing GCL, observed that the Temporary sector (T) had a statistically&#x0D; significant decrease (p

Anatomic Response to Intravitreal Dexamethasone Implant and Baseline Aqueous Humor Cytokine Levels in Diabetic Macular Edema.

To determine whether baseline cytokine aqueous humor (AH) levels are associated with diabetic macular edema (DME) anatomic response to dexamethasone intravitreal implant (DEX) injection. This was a prospective cohort study of DME cases receiving DEX treatment. Seventy patients were recruited with center-involving DME with spectral-domain (SD) optical coherence tomography (OCT) detection of central macular thickness (CMT) ≥300 μm on macular cube 518 × 128-μm scan protocol (Cirrus SD-OCT). DEX injection and anterior chamber tap to obtain an AH sample were performed at the same time. Multiplex immunoassay was carried out for interleukin (IL)-1β, IL-3, IL-6, IL-8, IL-10; monocyte chemoattractant protein (MCP)-1; interferon gamma-induced protein (IP)-10; tumor necrosis factor (TNF)-α; and vascular endothelial growth factor (VEGF). A follow-up visit and OCT exam were undertaken 6 to 8 weeks afterward. The association between AH cytokine baseline levels and change in CMT and macular volume (MV) was defined as main outcome measure. Multivariate linear regression analysis showed a higher decrease in MV to be associated (Rs of 0.512) with four baseline items: higher MCP-1 (β = -0.4; P = 0.028), higher CMT (β = -0.003; P = 0.024), decreased visual acuity (β = -0.7; P = 0.040), and a diffuse retinal thickening (DRT) OCT pattern (β = -1.3; P < 0.001). Logistic regression found DRT also to be associated with higher odds of a good MV response (odds ratio, 31.96; 95% confidence interval [CI] 7.11-143.72; P < 0.001). Even though visual acuity response and anatomic effect are not always correlated in DME, we found that baseline elevated MCP-1 AH levels and DRT pattern were biomarkers that predicted a future favorable anatomic response to DEX.

Comparison of persistent submacular fluid in different preoperative macular status after vitrectomy for rhegmatogenous retinal detachment.

To compare the incidence of persistent submacular fluid (SMF) and visual outcome after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD) in different preoperative macular status according to optical coherence tomography (OCT). A non-randomized, retrospective review was performed for patients who underwent successful PPV for RRD. OCT exams were taken preoperatively and 1mo after surgery, until SMF disappeared. According to the preoperative macular status on OCT, patients were divided into two groups: macula-off RRD (Group A) and macula-on RRD (Group B). In Group A, there were two subgroups: macula partly detached (Group A1) and macula totally detached (Group A2). The main outcome measures were the presence of SMF on OCT 1mo after surgery, and the preoperative and postoperative best corrected visual acuities (BCVA), among the different groups and depending on the presence or absence of persistent SMF. A total of 139 eyes of 139 patients were included in the study. Persistent SMF at 1mo after surgery was 15.8% (22/139), all occurring in Group A (22/101); Group B had no SMF at 1mo after surgery (0/38, P=0.002). The incidence of persistent SMF at 1mo after surgery in Group A1 was 50% (14/28), and in Group A2 was 11.0% (8/73, P<0.001). Significant differences were shown between the presence and absence of persistent SMF on foveola-off RRD, the preoperative BCVA, the 1mo postoperative BCVA, and the degree of the BCVA improvement from 1mo postoperatively to the final follow-up (P<0.05). However, there were no significant differences in the final BCVA (P>0.05). Persistent SMF after PPV for retinal detachment is associated with preoperative macular status. Macula-uninvolving RRD shows no persistent SMF after PPV. Macular partly detached RRD has a higher incidence of SMF than macula totally detached RRD after PPV. The persistence of SMF may be responsible for the delayed visual recovery, whereas there were no significant differences in the final visual acuity.

Comparison of color discrimination in chronic heavy smokers and healthy subjects

Background: Cigarette smoke is probably the most significant source of exposure to toxic chemicals for humans, involving health-damaging components, such as nicotine, hydrogen cyanide and formaldehyde. The aim of the present study was to assess the influence of chronic heavy smoking on color discrimination (CD). Methods: All subjects were free of any neuropsychiatric disorder, identifiable ocular disease and had normal acuity. No abnormalities were detected in the fundoscopic examination and in the optical coherence tomography exam. We assessed color vision for healthy heavy smokers (n = 15; age range, 20-45 years), deprived smokers (n = 15, age range 20-45 years) and healthy non-smokers (n = 15; age range, 20-45 years), using the psychophysical forced-choice method. All groups were matched for gender and education level. In this test, the volunteers had to choose the pseudoisochromatic stimulus containing a test frequency at four directions (e.g., up, down, right and left) in the subtest of Cambridge Colour Test (CCT): Trivector. Results: Performance on CCT differed between groups, and the observed pattern was that smokers had lower discrimination compared to non-smokers. In addition, deprived smokers presented lower discrimination to smokers and non-smokers. Contrary to expectation, the largest differences were observed for medium and long wavelengths. Conclusions: These results suggests that cigarette smoking, chronic exposure to its compounds, and withdrawal from nicotine affect color discrimination. This highlights the importance of understanding the diverse effects of nicotine on attentional bias.

Effects of smoking and smoking abstinence on spatial vision in chronic heavy smokers

Cigarette smoke is a complex chemical mixture, involving health-damaging components such as carbon monoxide, ammonia, pyridine, toluene and nicotine. While cognitive functions have been well documented in heavy smokers, spatial vision has been less characterized. In the article, we investigated smoking effects through contrast sensitivity function (CSF), a rigorous procedure that measures the spatial vision. Data were recorded from 48 participants, a group of non-smokers (n = 16), a group of chronic and heavy cigarette smokers (n = 16) and deprived smokers (n = 16); age range 20–45 years. Sinewave gratings with spatial frequencies ranging from 0.25 to 20 cycles per degree were used. All subjects were free from any neurological disorder, identifiable ocular disease and had normal acuity. No abnormalities were detected in the fundoscopic examination and in the optical coherence tomography exam. Contrary to expectations, performance on CSF differed between groups. Both smokers and deprived smokers presented a loss of contrast sensitivity compared to non-smokers. Post-hoc analyses suggest that deprived smokers were less sensitive at all spatial frequencies. These results suggest that not only chronic exposure to cigarette compounds but also withdrawal from nicotine affected spatial vision. This highlights the importance of understanding diffuse effects of smoking compounds on visual spatial processing.

Comparison of color discrimination in chronic heavy smokers and healthy subjects

Background: Cigarette smoke is probably the most significant source of exposure to toxic chemicals for humans, involving health-damaging components, such as nicotine, hydrogen cyanide and formaldehyde. The aim of the present study was to assess the influence of chronic heavy smoking on color discrimination (CD). Methods: All subjects were free of any neuropsychiatric disorder, identifiable ocular disease and had normal acuity. No abnormalities were detected in the fundoscopic examination and in the optical coherence tomography exam. We assessed color vision for healthy heavy smokers (n = 15; age range, 20-45 years), deprived smokers (n = 15, age range 20-45 years) and healthy non-smokers (n = 15; age range, 20-45 years), using the psychophysical forced-choice method. All groups were matched for gender and education level. In this paradigm, the volunteers had to choose the pseudoisochromatic stimulus containing a test frequency at four directions (e.g., up, down, right and left) in the subtest of Cambridge Colour Test (CCT): Trivector. Results: Performance on CCT differed between groups, and the observed pattern was that smokers had lower discrimination compared to non-smokers. In addition, deprived smokers presented lower discrimination to smokers and non-smokers. Contrary to expectation, the largest differences were observed for medium and long wavelengths. Conclusions: These results suggests that cigarette smoke and chronic exposure to nicotine, or withdrawal from nicotine, affects CD. This highlights the importance of understanding the diffuse effects of nicotine either attentional bias on color vision.

Comparison of color discrimination in chronic heavy smokers and healthy subjects

Background: Cigarette smoke is probably the most significant source of exposure to toxic chemicals for humans, involving health-damaging components, such as nicotine, hydrogen cyanide and formaldehyde. The aim of the present study was to assess the influence of chronic heavy smoking on color discrimination (CD). Methods: All subjects were free of any neuropsychiatric disorder, identifiable ocular disease and had normal acuity. No abnormalities were detected in the fundoscopic examination and in the optical coherence tomography exam. We assessed color vision for healthy heavy smokers ( n = 15; age range, 20-45 years), deprived smokers ( n = 15, age range 20-45 years) and healthy non-smokers ( n = 15; age range, 20-45 years), using the psychophysical forced-choice method. All groups were matched for gender and education level. In this test, the volunteers had to choose the pseudoisochromatic stimulus containing a test frequency at four directions (e.g., up, down, right and left) in the subtest of Cambridge Colour Test (CCT): Trivector. Results: Performance on CCT differed between groups, and the observed pattern was that smokers had lower discrimination compared to non-smokers. In addition, deprived smokers presented lower discrimination to smokers and non-smokers. Contrary to expectation, the largest differences were observed for medium and long wavelengths. Conclusions: These results suggests that cigarette smoking, chronic exposure to its compounds, and withdrawal from nicotine affect color discrimination. This highlights the importance of understanding the diverse effects of nicotine on attentional bias.

Comparison of color discrimination in chronic heavy smokers and healthy subjects.

Background: Cigarette smoke is probably the most significant source of exposure to toxic chemicals for humans, involving health-damaging components, such as nicotine, hydrogen cyanide and formaldehyde. The aim of the present study was to assess the influence of chronic heavy smoking on color discrimination (CD). Methods: All subjects were free of any neuropsychiatric disorder, identifiable ocular disease and had normal acuity. No abnormalities were detected in the fundoscopic examination and in the optical coherence tomography exam. We assessed color vision for healthy heavy smokers ( n = 15; age range, 20-45 years), deprived smokers ( n = 15, age range 20-45 years) and healthy non-smokers ( n = 15; age range, 20-45 years), using the psychophysical forced-choice method. All groups were matched for gender and education level. In this paradigm, the volunteers had to choose the pseudoisochromatic stimulus containing a test frequency at four directions (e.g., up, down, right and left) in the subtest of Cambridge Colour Test (CCT): Trivector. Results: Performance on CCT differed between groups, and the observed pattern was that smokers had lower discrimination compared to non-smokers. In addition, deprived smokers presented lower discrimination to smokers and non-smokers. Contrary to expectation, the largest differences were observed for medium and long wavelengths. Conclusions: These results suggests that cigarette smoke and chronic exposure to nicotine, or withdrawal from nicotine, affects CD. This highlights the importance of understanding the diffuse effects of nicotine either attentional bias on color vision.

Macular Ganglion Cell Layer Assessment to Detect Glaucomatous Central Visual Field Progression

PurposeTo investigate the use of ganglion cell inner plexiform layer (GC-IPL) thickness, as measured by spectral domain optical coherence tomography, to detect central visual field (VF) progression.MethodsThis study included 384 eyes from 384 patients (219 preperimetric and 165 perimetric glaucomatous eyes; average follow-up, 4.3 years). Photographic assessment of retinal nerve fiber layer (RNFL) and serial VF analysis were performed to detect glaucoma progression in the central (within 10°) area. Study inclusion required at least five serial spectral domain optical coherence tomography exams at different visits. The long-term test-retest variability of average GC-IPL thicknesses was calculated in 110 stable preperimetric glaucomatous eyes. The sensitivity and specificity of GC-IPL measurements for the detection of central VF progression were calculated in an event-based analysis using the calculated variability as a cut-off and were compared with those of central RNFL photographic assessment.ResultsThe intersession test-retest variability, defined as the 95% confidence interval, was 1.76 µm for average GC-IPL thickness. The sensitivity and specificity of the average GC-IPL thickness for detecting central VF progression were 60.7% and 78.9%, respectively. Among six sectors, the inferonasal GC-IPL sector showed the highest sensitivity (53.6%). The sensitivity of the ≥1 sector GC-IPL to detect central VF progression was significantly higher than that of central RNFL photographic progression (p = 0.013). Other GC-IPL parameters showed comparable sensitivity and specificity to detect central VF progression compared with RNFL photographic progression.ConclusionsSerial GC-IPL measurements show comparable performance in the detection of central glaucomatous VF progression to RNFL photographic assessment.

A Brazilian report using serological and molecular diagnosis to monitoring acute ocular toxoplasmosis.

BackgroundToxoplasmosis was recently included as a neglected disease by the Center for Disease Control. Ocular toxoplasmosis is one clinical presentation of congenital or acquired infection. The laboratory diagnosis is being used worldwide to support the clinical diagnosis and imaging. The aim of this study was to evaluate the use of serology and molecular methods to monitor acute OT in immunocompetent patients during treatment.MethodsFive immunocompetent patients were clinically diagnosed with acute OT. The clinical evaluation was performed by ophthalmologic examination using the Early Treatment Diabetic Retinopathy Study, best-corrected visual acuity, slit lamp biomicroscopy, fundoscopic examination with indirect binocular ophthalmoscopy color fundus photography, fluorescein angiography and spectral optical coherence tomography (OCT). Serology were performed by ELISA (IgA, IgM, IgG) and confirmed by ELFA (IgG, IgM). Molecular diagnoses were performed in peripheral blood by cPCR using the Toxoplasma gondiiB1 gene as the marker. Follow-up exams were performed on day +15 and day +45.ResultsOnly five non-immunocompromised male patients completed the follow up and their data were used for analysis. The mean age was 41.2 ± 11.3 years (median: 35; range 31–54 years). All of them were positive for IgG antibodies but with different profiles for IgM and IgA, as well as PCR. For all patients the OCT exam showed active lesions with the inner retinal layers being abnormally hyper-reflective with full-thickness disorganization of the retinal reflective layers, which assumed a blurred reflective appearance and the retina was thickened.ConclusionsThe presence of IgA and IgM confirmed the acute infection and thus was in agreement with the clinical evaluation. Our results show the adopted treatment modified the serological profile of IgM antibodies and the PCR results, but not the IgG and IgA antibodies and that imaging is a good tool to follow-up patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s13104-015-1650-6) contains supplementary material, which is available to authorized users.