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Purpose: To evaluate the repeatability of the new spectral domain optical coherence tomography (HOCT-1F), and also to evaluate the agreement between vertical and horizontal scan protocols. In addition, we also evaluated the relation between the repeatability and age., Methods: Three consecutive measurements of the inner limiting membrane-retinal pigment epithelium (ILM-RPE), inner limiting membrane-inner plexiform layer (ILM-IPL) from macular horizontal and vertical scans, and inner limiting membrane-retinal nerve fiber layer (ILM-RNFL) from optic disc horizontal scan. 159 subjects were included in the analysis. The within subject standard deviation (Sw) and the repeatability limits (Rlimit) are used to represent the repeatability of the parameters for the different sectors., Results: The Sw for the ILM-RPE thickness was less than 3.5 μm for each sector and scan direction. The Sw values varied within the sectors and scan modes, with horizontal scan modes resulting in better values for the horizontal sectors, and vice versa. The Sw for the GCL-IPL thickness was less than 2 μm, and was similar between the vertical and horizontal scan modes for each sector map. For the optic disc scan, the Sw was not symmetric along the clock-hour map sectors, the largest Sw values were seen in the vertical sectors (8.6 μm). The mean difference between the vertical and horizontal scans was less than 2 μm for each retinal thickness sector map. Significant but weak correlation between the Sw and the subject's age was seen in both macular and optic disc scans., Conclusions: The repeatability of the HOCT-1F to measure the ILM-RPE-, ILM-IPL- and ILM-RNFL-thickness is good. The repeatability of the ILM-RPE thickness is dependent on the scan direction, which should be taken into account when calculating retinal thickness. There is a weak correlation between the repeatability and the subject's age., Competing Interests: The authors have declared that no competing interests exist.

Background: Optical coherence tomography (OCT), can be used in clinical practice to provide high resolution cross-sectional images of the retina, optic disc and macula structure. These measurements can be useful for early detection, diagnosis, monitoring and treatment guidance for retinal diseases. Therefore, repeatability of measurements in OCT is of great importance., Methods: Macula and optic disc parameters from the right eye of 30 healthy subjects were obtained twice with the Canon OCT-HS100 and Zeiss Cirrus HD-OCT 5000. Repeatability was evaluated by use of the coefficient of repeatability (CR) and the coefficient of repeatability as a percentage of the mean (CR%), and the obtained measurements were compared between the instruments., Results: CR% of optic disc parameters ranged between 0.90 and 22.22% and 0.00 and 16.00% with the Canon and Zeiss OCT respectively. For macular parameters CR% ranged between 0.62 and 2.81% and 0.99 and 1.81% with the Canon and Zeiss OCT respectively. No statistical difference could be found when comparing the CR of all macular and disc measurements between the instruments. Compared to our previously published data repeatability has significantly improved with the inclusion of automatic tracking systems with both the Canon and Zeiss OCT., Conclusion: Automatic tracking function improves repeatability in both Canon OCT-HS100 and Zeiss Cirrus HD-OCT 5000. However, measurements generated by the two instruments are still not interchangeable.

Background: This study sought to establish the association between retinal morphology, visual function and linear parameters of cerebral atrophy in non‐immunocompromised people living with HIV (NIPLHIV). Methods: Sixty participants (30 NIPLHIV, 30 controls), aged 18–45 years, were sourced from an outpatient clinic in South Africa. NIPLHIV on antiretroviral therapy (ART) had elevated CD4 counts and low viral loads. Macula thickness and volume measurements were obtained using the Spectralis optical coherence tomographer. Contrast sensitivity (CS), colour vision and visual‐evoked potentials (VEP) were also obtained. Linear parameters of cerebral atrophy (Sylvian fissure ratio, SFR) and bicaudate nucleus ratio (BCR) were all acquired from computed tomography (CT) scans. Associations between retinal thickness and volume and visual function were established by principal component factor analysis. Results: CS scores were indirectly associated with the Inner Nuclear Layer (INL)‐ETDRS thickness and volume subfields (co‐efficient = −0.07; p = 0.02 and −0.11; p = 0.001), respectively. F100 total error scores (TES) were directly associated with the thicknesses of Ganglion Cell Layer‐ETDRS subfields (co‐efficient = 6.06; p = 0.04) but indirectly associated with INL‐ETDRS subfields (co‐efficient = −5.49; p = 0.04). F100‐TES were indirectly associated with volumes of RNFL (Retinal Nerve Fibre Layer)‐ETDRS subfields (co‐efficient = −5.54; p = 0.02) and inner retina ‐ETDRS subfields (co‐efficient = −6.70; p = 0.02). P100 latency was directly associated with RNFL‐ETDRS subfield thickness (co‐efficient = 2.90; p = 0.02) and volumes of outer retina subfields (co‐efficient = 2.72; p = 0.04). CS scores were directly associated with SFR (co‐efficient = −0.04; p = 0.01). F100‐TES were directly associated with BCR (co‐efficient = 0.003; p = 0.004) and SFR (co‐efficient = 0.002; p = 0.02). P100 latency was indirectly associated with BCR (co‐efficient = −0.001; p = 0.03). Conclusion: The recognition of associations may be the first step in the proposal to develop a framework for the surveillance of vision in patients with NIPLHIV. We recommend a study of the sample population to track the stability of these observations before general recommendations for clinical care. [ABSTRACT FROM AUTHOR]