New technique enhances imaging of retinal tissueMay 8, 2021
Rongwen Lu et al developed a new technique to improve imaging resolution to visualise photoreceptor cells in the eyes in greater detail. This could help monitor cell changes in retinal tissue that could aid in early detection and prevention of vision loss. Using an annular pupil illumination, the team could block the light in the middle of the beam that illuminates the eye and creates a ring of light rather than a disk. This improved the transverse resolution from 2.36 to 1.58 µm across the mosaic. The team also blocked the light coming back from the eye using a super small pinhole, called a sub-Airy disk, which recovered the axial resolution by 13% that would have been lost while using the ring of light alone. Combining the ring illumination with the sub-Airy disk imaging resulted in a 33% increase in resolution, which made it easier to see rods, as well as subcellular details within cones. Their technique also enhanced the visualisation of the photoreceptor mosaic with another technique called non-confocal split-detection adaptive optics scanning light ophthalmoscopy (AOSLO) providing a complementary view of the cone and rod photoreceptor mosaic.
Source: Optica Vol. 8, Issue 3, pp. 333-343 (2021) https://doi.org/10.1364/OPTICA.414206