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The existence of a correlation between the results of paraclinical retinal imaging and clinical tests such as contrast sensitivity can reduce time and cost in diagnosing optic neuritis (ON). To demonstrate whether changes of peripapillary retinal nerve fibre layer (RNFL) thickness are correlated with the results of visual acuity, contrast sensitivity and colour vision in eyes with acute ON. Thirty patients with acute ON, 23 females and seven males, who had no previous history of ON in neither eye, were examined. Inclusion criteria were: subjects had spherical refraction of less than ±5D, no prior ON or optic disc swelling, no history of amblyopia or colour blindness, and no history or ophthalmoscopic evidence of glaucoma, diabetic retinopathy, or maculopathies. Visual acuity, contrast sensitivity and colour vision were tested and optical coherence tomography was performed for all patients after complete ophthalmologic examinations including refraction, biomicroscopy, and funduscopy with a 90D lens by a neuro-ophthalmologist. Thirty patients who were 18–45 years old entered the study. There was an inverse correlation between contrast sensitivity and nasal (r = −0.430, p = 0.018), inferior (r = −0.503, p = 0.005) and mean (r = −0.510, p = 0.004) RNFL thickness. The multiple linear regression model, after adjustment for age and sex, showed a significant association between visual acuity and nasal RNFL thickness (coefficient = 0.025, p = 0.032). There was also a significant inverse correlation between contrast sensitivity and nasal (coefficient = −0.003, p = 0.036), inferior (coefficient = −0.006, p = 0.010) and mean (coefficient = −0.007, p = 0.012) RNFL thickness. No significant correlation was found between colour vision and RNFL thickness. Contrast sensitivity is more correlated with changes in RNFL thickness in comparison with visual acuity and colour vision. Contrast sensitivity measurement therefore can be used as one of the first assessments in patients with ON. [ABSTRACT FROM AUTHOR]

Spatial processing deficits are the reason for many daily life problems of schizophrenia (SCZ) patients. In this study, we aimed to examine the possibility of abnormal bias to one hemifield, in form of hemispatial neglect and extinction, in auditory modality in SCZ. Twenty-five SCZ patients and 25 healthy individuals were compared on speech tasks to study the auditory neglect and extinction, as well as an auditory localization task for studying neglect. In the speech tasks, participants reproduced some nonsense syllables, played from one or two speakers on the right and/or left sides. On the localization task, examinees discriminated the subjective location of the noise stimuli presented randomly from five speakers. On the speech task, patients had significantly lower hit rates for the right ear compared with controls (p = 0.01). While healthy controls showed right ear advantage, SCZs showed a left ear priority. In the localization task, although both groups had a left-side bias, this bias was much more prominent for the patients (all p < 0.05). SCZ could potentially alter the auditory spatial function, which may appear in the form of auditory neglect and extinction on the right side, depending on the characteristics of patient population. [ABSTRACT FROM AUTHOR]

Background and Aim: Stress could play either helpful or harmful roles in vestibular compensation, the process of recovery after vestibular system lesions. Herein, we examined the effect of two stressor types on vestibular compensation: chronic anxiety disorder induced by early maternal separation (MS), and caloric restriction by an intermittent fasting (IF) diet. Methods: Male Wistar rats (n=56) received maternal separation (the MS group), intermittent fasting (IF group), unilateral vestibular deafferentation (UVD group), or a mixture of these interventions (UVD+IF, UVD+MS, and UVD+IF+MS). All the groups were compared with control animals. The animals' balance, motor coordination, anxiety, locomotor activity, and serum cortisol levels were evaluated by rotarod, open field, and enzyme-linked immunosorbent assay methods, respectively. The data were compared with those of the healthy control (HC) group. Results: The UVD animals did not show a significant change in the time on the rod, except for the IF+UVD group (p=0.04). There was no significant difference between the experimental groups on the open field indices, except for the MS+IF+UVD group which traveled a significantly less total distance (p=0.02). Serum cortisol levels were significantly higher than HCs for all the groups except for the sham saline and IF+UVD group (p<0.05). Conclusion: IF seems to promote compensation after UVD, while MS may disrupt it. However, IF loses its beneficial outcomes if the animal has received another source of stress, i.e. MS. [ABSTRACT FROM AUTHOR]

We aimed to determine the association between ocular biometric components and near work in bank employees. This study was conducted as an analytical cross-sectional study in Sari, north of Iran, 2015. A group of bank employees and a control group were randomly selected. After applying the inclusion criteria, all selected subjects had a set of examinations including refraction, uncorrected and corrected visual acuity, slit lamp biomicroscopy and ophthalmoscopy. Then ocular biometric indices were measured using a Nidek biometer (US 800). Mean spherical equivalent was -0.53 (95% CI: -0.7 to -0.36) diopter (D) in bank employees and 0.09(95% CI: -0.05 to 0.23) D in the control group (P<0.001). After adjusting for age and gender, axial length and vitreous chamber depth were significantly longer in bank employees. In a lineare regression model, near work significantly correlated with increasing axial length (Unstandardized Coefficients=0.153, P<0.001) and decreasing corneal radius of curvature (-0.049, P<0.001) after adjusting for age, gender, and refractive error. Corneal curvature and axial length correlated more strongly with axial length in bank employees compared to the control group. Ocular biometric components, especially axial length, lens thickness, and corneal radius of curvature, significantly differ between people with a history of near work and those without one. [ABSTRACT FROM AUTHOR]

Background and Aim: Behavioral audiometry is the best method of hearing evaluation. Hearing thresholds are estimated with auditory evoked responses in patients who are not able to cooperate in behavioral audiometry. Because rehabilitative decisions are based on behavioral thresholds, it is essential to determine the amount of difference between behavioral and evoked response thresholds. The purpose of this study was to evaluate the difference between functional and auditory steady-state response (ASSR) gains. Methods: Twenty six moderate to severe hearing impaired adolescents and adults (age range: 14 to 55 years) participated in this interventional-comparative study. Audiometery and ASSR testing was performed (without hearing aid and then with hearing aid). Finally, functional gain with ASSR gain, and behavioral thresholds with ASSR thresholds were compared using paired t-test and correlation statistical methods. All tests were performed in the sound field. Results: The mean difference was 6.19 dB between unaided behavioral and ASSR thresholds, 4.33 dB between aided thresholds, and 2.43 dB between functional and ASSR gains. There was no significant difference between functional and ASSR gains (p>0.05). Conclusion: The difference between functional and ASSR gains is less than the difference between behavioral and ASSR thresholds and it has less variability between different frequencies. So, it may be better to use ASSR gain instead of ASSR thresholds in hearing aid fitting in difficult-to-test population. [ABSTRACT FROM AUTHOR]

The oxidative conversion of alcohols or aldehydes to the corresponding nitriles in moderate to good yields was easily achieved by treatment of H5IO6 and KI in aqueous NH3. This simple and one-pot system provides easy workup and separation of the product. [ABSTRACT FROM PUBLISHER]

Poly(4-vinylpyridinium nitrate) was found to be a recyclable and highly efficient oxidizing polymer for the oxidative coupling of a variety of aliphatic or aromatic thiols to the corresponding disulfides. Poly(4-vinylpyridinium nitrate) is an extremely mild agent, which gave no other oxidized side products. [image omitted] [ABSTRACT FROM AUTHOR]

Aim: To determine the agreement of ocular biometric indices including axial length, keratometric readings, anterior chamber depth, and horizontal corneal diameter between the Pentacam AXL and IOL Master 500., Methods: The study was a large cross-sectional population-based study (Tehran Geriatric Eye Study) conducted from Jan 2019 to Jan 2020. A total of 160 clusters were randomly selected proportional to size (each cluster contained 20 individuals) from 22 strata of Tehran city. All people aged 60y and above were invited to participate in the study. For all participants, preliminary ocular examinations were performed including the measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, anterior and posterior segment examinations. All participants underwent an ocular biometry using the Pentacam AXL and IOL Master 500., Results: The 95% limits of agreement (LoA) between the two devices were -0.13 to 0.19, -0.15 to 0.17, and -0.13 to 0.19 in normal, pseudophakic, and cataractous eyes, respectively. With increasing the axial length, the difference between the two devices significantly increased in all three groups of normal, pseudophakic, and cataractous eyes ( P <0.001). The 95% LoAs between the two devices regarding the mean keratometry shows that the best LoAs were seen in cataractous (-0.33 to 0.81) and followed by normal eyes (-0.36 to 0.86) and the pseudophakic eyes (-0.48 to 0.90) had the widest LoA. The 95% LoAs for horizontal corneal diameter measurements were -0.08 to 0.86, -0.03 to 0.83, and -0.07 to 0.87 in normal, pseudophakic, and cataractous eyes, respectively. The 95% LoAs of anterior chamber depth measurements between the two devices was -0.39 to 0.19 and -0.37 to 0.13 in normal eyes and cataractous, respectively., Conclusion: The Pentacam AXL has excellent agreement with the gold standard, IOL Master 500 in measuring axial length. In eyes with cataracts, the difference between the two devices is more scattered. With the increasing of axial length, the difference between the two devices increased, which should be considered when using Pentacam AXL., (International Journal of Ophthalmology Press.)

Purpose: To determine economic inequality in visual impairment (VI) and its determinants in the rural population of Iran., Methods: In this population-based, cross-sectional study, 3850 individuals, aged 3-93 years were selected from the north and southwest regions of Iran using multi-staged stratified cluster random sampling. The outcome was VI, measured in 20 feet. Economic status was constructed using principal component analysis on home assets. The concentration index ( C ) was used to determine inequality, and the gap between low and high economic groups was decomposed to explained and unexplained portions using the Oaxaca-Blinder decomposition method., Results: Of the 3850 individuals that were invited, 3314 participated in the study. The data of 3095 participants were finally analyzed. The C was -0.248 (95% confidence interval [CI]: -0.347 - -0.148), indicating a pro-poor inequality (concentration of VI in low economic group). The prevalence (95% CI) of VI was 1.72% (0.92-2.52) in the high economic group and 10.66% (8.84-12.48) in the low economic group with a gap of 8.94% (6.95-10.93) between the two groups. The explained and unexplained portions comprised 67.22% and 32.77% of the gap, respectively. Among the study variables, age (13.98%) and economic status (80.70%) were significant determinants of inequality in the explained portion. The variables of education (coefficient: -4.41; P < 0.001), age (coefficient: 14.09; P < 0.001), living place (coefficient: 6.96; P : 0.006), and economic status (coefficient: -7.37; P < 0.001) had significant effects on inequality in the unexplained portion., Conclusions: The result showed that VI had a higher concentration in the low economic group, and the major contributor of this inequality was economic status. Therefore, policymakers should formulate appropriate interventions to improve the economic status and alleviate economic inequality., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Journal of Current Ophthalmology.)

Purpose: To determine the distribution of residual and corneal astigmatism (CA) in children aged 6-18 years and their relationship with age, sex, spherical equivalent, and biometric parameters., Methods: In this cross-sectional study, multi-stage stratified cluster sampling was done to select students from Dezful, a city in Southwestern Iran. Examinations included the measurement of visual acuity with and without optical correction, refraction with and without cycloplegia, and biometry using the Biograph (Lenstar, Germany). The main outcomes in this report were corneal and residual astigmatism. The CA was measured by Biograph (difference between k1 and k2), and residual astigmatism was calculated using Alpine method. The power vector method was applied to analyze the data of astigmatism., Results: Of 864 students that were selected, 683 (79.1%) participated in the study. The mean residual and CA were -0.84 diopter (D) and -0.85 D, respectively. According to the results of J0 and J45 vectors, residual astigmatism was -0.33 D and 0.04 D, and CA was 0.38 D and 0.01 D, respectively. With-the-rule (WTR), against-the-rule (ATR), and oblique astigmatism were seen in 3.4%, 66.8%, and 4.5% of the children with residual astigmatism and 67.94%, 1.3%, and 1.5% of the children with CA. Residual astigmatism decreased with an increase in spherical refractive error, whereas CA increased with an increase in spherical refractive error., Conclusion: The results of the present study showed a high prevalence and amount of residual astigmatism with ATR pattern among the 6-18-year-old population and the compensatory effect of this type of astigmatism on CA that mostly followed a WTR pattern., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Journal of Current Ophthalmology.)