Automation improves repeatability of retinal oximetry measurements

Purpose Retinal oximetry is a technique based on spectrophotometry where images are analyzed with software capable of calculating vessel oxygen saturation and vessel diameter. In this study, the effect of automation of measurements of retinal vessel oxygen saturation and vessel diameter is explored. Methods Until now, operators have had to choose each vessel segment to be measured explicitly. A new, automatic version of the software automatically selects the vessels once the operator defines a measurement area. Five operators analyzed image pairs from the right eye of 23 healthy subjects with semiautomated retinal oximetry analysis software, Oxymap Analyzer (v2.5.1), and an automated version (v3.0). Inter- and intra-operator variability was investigated using the intraclass correlation coefficient (ICC) between oxygen saturation measurements of vessel segments in the same area of the retina. Results For semiautomated saturation measurements, the inter-rater ICC was 0.80 for arterioles and venules. For automated saturation measurements, the inter-rater ICC was 0.97 for arterioles and 0.96 for venules. For semiautomated diameter measurements, the inter-rater ICC was 0.71 for arterioles and venules. For automated diameter measurements the inter-rater ICC was 0.97 for arterioles and 0.95 for venules. The inter-rater ICCs were different (p < 0.01) between the semiautomated and automated version in all instances. Conclusion Automated measurements of retinal oximetry values are more repeatable compared to measurements where vessels are selected manually.

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Automation improves repeatability of retinal oximetry measurements

10.1101/2021.08.25.21262154 ◽

2021 ◽

Author(s):

Robert Arnar Karlsson ◽

Olof Birna Olafsdottir ◽

Soumaya Belhadj ◽

Vedis Helgadottir ◽

Thorunn Scheving Eliasdottir ◽

...

Keyword(s):

Oxygen Saturation ◽

Intraclass Correlation ◽

Retinal Vessel ◽

Vessel Diameter ◽

Automated Measurements ◽

Automation Of Measurements ◽

Image Pairs ◽

The Right ◽

Measurement Area ◽

Retinal Oximetry

AbstractPurposeRetinal oximetry is a technique based on spectrophotometry where images are analyzed with software capable of calculating vessel oxygen saturation and vessel diameter. In this study, the effect of automation of measurements of retinal vessel oxygen saturation and vessel diameter is explored.MethodsUntil now, operators have had to choose each vessel segment to be measured explicitly. A new, automatic version of the software automatically selects the vessels once the operator defines a measurement area.Five operators analyzed image pairs from the right eye of 23 healthy subjects with semiautomated retinal oximetry analysis software, Oxymap Analyzer (v2.5.1), and an automated version (v3.0). Inter- and intra-operator variability was investigated using the intraclass correlation coefficient (ICC) between oxygen saturation measurements of vessel segments in the same area of the retina.ResultsFor manual saturation measurements, the inter-rater ICC was 0.80 for arterioles and venules. For automated saturation measurements, the inter-rater ICC was 0.97 for arterioles and 0.96 for venules. For manual diameter measurements, the inter-rater ICC was 0.71 for arterioles and venules. For automated diameter measurements the inter-rater ICC was 0.97 for arterioles and 0.95 for venules. The inter-rater ICCs were different (p < 0.01) between the semiautomated and automated version in all instances.ConclusionAutomated measurements of retinal oximetry values are more repeatable compared to measurements where vessels are selected manually.

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Retinal vessel oxygen saturation and vessel diameter in high myopia

Ophthalmic and Physiological Optics ◽

10.1111/opo.12223 ◽

2015 ◽

Vol 35 (5) ◽

pp. 562-569 ◽

Cited By ~ 15

Author(s):

Qishan Zheng ◽

Yao Zong ◽

Li Li ◽

Xia Huang ◽

Leilei Lin ◽

...

Keyword(s):

Oxygen Saturation ◽

High Myopia ◽

Retinal Vessel ◽

Vessel Diameter

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Shifts in retinal vessel diameter and oxygen saturation in Chinese type 2 diabetes mellitus patients

BMC Ophthalmology ◽

10.1186/s12886-016-0217-1 ◽

2016 ◽

Vol 16 (1) ◽

Cited By ~ 9

Author(s):

Yanmin Dong ◽

Leilei Lin ◽

Hong Yan ◽

Yue Fu ◽

Yao Zong ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Oxygen Saturation ◽

Retinal Vessel ◽

Vessel Diameter ◽

Retinal Vessel Diameter

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The Difference in Repeatability of Automated Superficial Retinal Vessel Density according to the Measurement Area Using OCT Angiography

Journal of Ophthalmology ◽

10.1155/2020/5686894 ◽

2020 ◽

Vol 2020 ◽

pp. 1-9

Author(s):

Hyung Bin Lim ◽

Tae Seen Kang ◽

Yeo Kyoung Won ◽

Jung Yeul Kim

Keyword(s):

Intraclass Correlation ◽

Retinal Vessel ◽

Vessel Density ◽

Foveal Avascular Zone ◽

Capillary Plexus ◽

The Difference ◽

Retinal Vessel Density ◽

Perfusion Density ◽

Measurement Area ◽

Central Fovea

Purpose. To evaluate the difference in the repeatability of automated superficial retinal vessel density and foveal avascular zone (FAZ) metrics according to the measurement area of optical coherence tomography angiography (OCTA). Methods. A total of 127 normal eyes from 127 healthy subjects were included. Macular angiography images were acquired from all subjects using the Zeiss Cirrus 5000 with AngioPlex™ OCTA software. Scans of 3 × 3 mm and 6 × 6 mm were each performed twice in a randomly arranged sequence. Vessel density (VD), perfusion density (PD), and FAZ metrics of the superficial capillary plexus were calculated automatically for all scans, and the repeatabilities for both scan patterns were assessed based on intraclass correlation (ICC), coefficient of variation (CV), and coefficient of repeatability (CR) parameters. The average measured values in the two scan patterns were also compared. Results. VD was significantly greater in the 3 × 3 mm scan than in the 6 × 6 mm scan according to all parameters, whereas PD was significantly less in the 3 × 3 mm scan than in the 6 × 6 mm scan. The ICCs for VDs in the central fovea were 0.826 and 0.741 for the 3 × 3 and 6 × 6 mm scans, respectively, and the CVs were 8.00% and 12.75%. For PDs, the ICCs were 0.839 and 0.762 and the CVs were 9.32% and 14.90%. The FAZ metrics in the 3 × 3 mm scan showed good repeatability with an ICC >0.75 and a CV <10.0%. However, all ICCs for the 6 × 6 mm scans were <0.75, and the CVs were all >10%. Conclusions. The 6 × 6 mm macular angiography scans resulted in lower repeatabilities than the 3 × 3 mm scans according to all OCTA parameters, particularly in the central fovea and FAZ metrics. The 3 × 3 mm scan was more suitable than the 6 × 6 mm scan for analyzing macular microvascular density and FAZ metrics.

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