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PURPOSE: To investigate the visual functions of truck drivers of the Kingdom of Saudi Arabia (KSA) in the region of Qassim and Dammam and to see if is there any association between these visual functions and self-reported road traffic accidents (RTA). METHODS: It is a cross-sectional, descriptive study. LogMAR visual acuity, refractive error, color vision, stereopsis, and confrontation visual fields were measured in 300 truck drivers in the Qassim and Dammam regions of KSA. Driving-related history and incidence of RTA from the past 3 years, systemic history, and general eye compliance history were collected through a self-reporting questionnaire. RESULTS: Among 300 truck drivers examined, 54 (18.4%) subjects have a refractive error, 14 (4.7%) subjects have color vision deficiency, 37 (12.2%) subjects have abnormal stereo acuity, and none of them have confrontation visual field defect. RTA was reported in 25 (8.3%) subjects. The current study has found RTA is significantly associated with refractive error (P = 0.01) and abnormal stereopsis (P < 0.01). Systemic history revealed that 11% of the subjects had diabetes mellitus. CONCLUSION: The current study is the first to report on the visual functions of KSA truck drivers. Hence, the current study has found a significant association between visual functions and RTA among truck drivers, we recommend a comprehensive examination need to be part of issuing driver's licenses in KSA. More studies with larger samples from different regions of KSA are needed to extrapolate these findings.
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Purpose: To assess the optic nerve head (ONH) parameters in normal male Saudi eyes using swept-source optical coherence tomography (SS-OCT). Materials and methods: The study included 86 healthy men with a mean age of 23.6 ± 4.82 years. The metrics collected using SS-OCT from each individual was disk area (DA), rim area (RA), cup volume (CV), linear cup-disk ratio (LCDR), vertical cup-disk ratio (VCDR), and total retinal nerve fiber layer (RNFL) thickness, superior RNFL thickness, and inferior RNFL thickness. All the metrics were correlated with the DA. The right eye data were used for the correlation analysis. Results: The mean DA in OD was 1.78 mm2 (range 1.09-2.70 mm2). The mean RA was 1.28 mm2 (range 0.72-2.47 mm2). The DA showed a significant positive correlation (p < 0.05) with RA, cup area (CA), CV, VCDR, LCDR, and total RNFL thickness. Conclusion: For the first time, using sweeping source OCT (DRI OCT Triton, Topcon Corporation), a normative database of ONH parameters was made accessible to the Saudi male population. While assessing the optic disk for progressive optic neuropathies like glaucoma, disk size should be taken into consideration since the optic DA affects ONH topography, especially in Saudi eyes. How to cite this article: Challa NK. Optic Nerve Head Parameters in Saudi Male Young Adults Using Swept-source Optical Coherence Tomography. J Curr Glaucoma Pract 2023;17(2):58-62.
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Electroretinograms (ERGs) elicited by transient, square-wave L- and M-cone isolating stimuli were recorded from human trichromatic (n=19) and dichromatic (n=4) observers. The stimuli were generated on a four primary LED stimulator and were equated in terms of cone modulation (cone contrast=0.11) and retinal illuminance (12,000 trolands). L- and M-cone isolated ERGs had waveforms similar to those observed for luminance responses. However, M-cone ERGs exhibited a phase reversal in their responses to onset and offset stimuli relative to the L-cone responses. This on-off response reversal was observed in trichromats but not dichromats. Simultaneous counterphase and inphase combinations of L- and M-cone isolating stimuli generated responses that reflected chromatic and luminance processing, respectively. We conclude that L- and M-cone specific ERGs provide a measure of how photoreceptors contribute to postreceptoral mechanisms.
