In vivo human retinal swept source optical coherence tomography and angiography at 830 nm with a CMOS compatible photonic integrated circuit

• Published in: Scientific reports Vol. 11; no. 1; pp. 21052 - 12
• Main Authors: Rank, Elisabet A., Nevlacsil, Stefan, Muellner, Paul, Hainberger, Rainer, Salas, Matthias, Gloor, Stefan, Duelk, Marcus, Sagmeister, Martin, Kraft, Jochen, Leitgeb, Rainer A., Drexler, Wolfgang
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 26.10.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 639/624/1075/1079; 639/624/399/1099; 692/700/1421/2025; Angiography; Angiography - instrumentation; Angiography - methods; Equipment Design; Humanities and Social Sciences; Humans; Integrated circuits; Medical imaging; multidisciplinary; Retina; Retina - diagnostic imaging; Science; Science (multidisciplinary); Tomography; Tomography, Optical Coherence - instrumentation; Tomography, Optical Coherence - methods
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-021-00637-4

Photonic integrated circuits (PIC) provide promising functionalities to significantly reduce the size and costs of optical coherence tomography (OCT) systems. This paper presents an imaging platform operating at a center wavelength of 830 nm for ophthalmic application using PIC-based swept source OCT. An on-chip Mach–Zehnder interferometer (MZI) configuration, which comprises an input power splitter, polarization beam splitters in the sample and the reference arm, and a 50/50 coupler for signal interference represents the core element of the system with a footprint of only ( 12 × 5 ) mm 2 . The system achieves 94 dB imaging sensitivity with 750  μ W on the sample, 50 kHz imaging speed and 5.5  μ m axial resolution (in soft tissue). With this setup, in vivo human retinal imaging of healthy subjects was performed producing B-scans, three-dimensional renderings as well as OCT angiography. These promising results are significant prerequisites for further integration of optical and electronic building blocks on a single swept source-OCT PIC.