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Register a new userOptical Incoherence Tomography: a method to generate tomographic retinal cross-sections with non-interferometric imaging systems
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Optical tomographic cross-sectional images of biological samples were made possible by interferometric imaging techniques such as Optical Coherence Tomography (OCT). Owing to its unprecedented view of the sample, OCT has become a gold standard, namely for human retinal imaging in the clinical environment. In this Letter, we present Optical Incoherence Tomography (OIT): a completely digital method extending the possibility to generate tomographic retinal cross-sections to non-interferometric imaging systems such as en-face AO-ophthalmoscopes. We demonstrate that OIT can be applied to different imaging modalities using back-scattered and multiply-scattered light including systems without inherent optical sectioning. We show that OIT can be further used to guide focus position when the user is blind focusing, allowing precise imaging of translucent retinal structures, the vascular plexuses and the retinal pigment epithelium using respectively split detection, motion contrast, and autofluorescence techniques.
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Wave-CAIPI MR imaging is a 3D imaging technique which can uniformize the g-factor maps and significantly reduce g-factor penalty at high acceleration factors. But it is time-consuming to calculate the average g-factor penalty for optimizing the parameters of Wave-CAIPI. In this paper, we propose a novel fast calculation method to calculate the average g-factor in Wave-CAIPI imaging. Wherein, the g-factor value in the arbitrary (e.g. the central) position is separately calculated and then approximated to the average g-factor using Taylor linear approximation. The verification experiments have demonstrated that the average g-factors of Wave-CAIPI imaging which are calculated by the proposed method is consistent with the previous time-consuming theoretical calculation method and the conventional pseudo multiple replica method. Comparison experiments show that the proposed method is averagely about 1000 times faster than the previous theoretical calculation method and about 1700 times faster than the conventional pseudo multiple replica method.
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