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Application of Optical Coherence Tomography to a Mouse Model of Retinopathy
Published on: January 12, 2022
The inner segment/outer segment border seen on optical coherence tomography is less intense in patients with
Donald C Hood1, Xian Zhang, Rithambara Ramachandran
1Department of Psychology, Columbia University, New York, New York 10027, USA. dch3@columbia.edu
Investigative Ophthalmology & Visual Science
|November 24, 2011
Summary
The inner segment ellipsoid (ISe) band
Area of Science:
- Ophthalmology
- Retinal Imaging
- Cone Photoreceptor Function
Background:
- The inner segment ellipsoid (ISe) band, also known as the inner segment/outer segment (IS/OS) border, is a clinically significant feature observed in optical coherence tomography (OCT) scans.
- Understanding the factors influencing the ISe band's appearance is crucial for diagnosing retinal conditions.
Purpose of the Study:
- To investigate the impact of diminished cone function on the signal intensity of the ISe band.
- To assess whether cone photoreceptors contribute to the visibility and intensity of the ISe band.
Main Methods:
- Frequency domain optical coherence tomography (fdOCT) was used to obtain horizontal line scans through the fovea of healthy controls and patients with achromatopsia and cone dystrophy.
- A computer-aided manual technique was employed to segment the ISe band, dividing it into specific regions for intensity analysis.
- Relative ISe intensity was calculated by comparing the signal intensity within ISe regions to that of a local reference region.
Main Results:
- All patients exhibited a discernible ISe band, except in the central fovea, across a ±3 mm region from the foveal center.
- A statistically significant reduction in relative ISe intensity was observed in patients with achromatopsia (1.14 ± 0.14) and cone dystrophy (1.27 ± 0.14) compared to healthy controls (1.61 ± 0.16).
- No significant differences in relative intensity were found in other retinal layers between the groups.
Conclusions:
- The reduced intensity of the ISe band in individuals with diminished cone function suggests a contribution of cones to its overall signal strength.
- These findings support the hypothesis that the complete absence or damage of both rod and cone photoreceptors is necessary for the ISe band to be entirely missing on OCT scans.
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