In vivo blind‐deconvolution photoacoustic ophthalmoscopy with total variation regularization

Abstract

Photoacoustic ophthalmoscopy (PAOM) is capable of noninvasively imaging anatomic and functional information of the retina in living rodents. However, the strong ocular aberration in rodent eyes and limited ultrasonic detection sensitivity affect PAOM's spatial resolution and signal-to-noise ratio (SNR) in in vivo eyes. In this work, we report a computational approach to combine blind deconvolution (BD) algorithm with a regularizing constraint based on total variation (BDTV) for PAOM imaging restoration. We tested the algorithm in retinal and choroidal microvascular images in albino rat eyes. The algorithm improved PAOM's lateral resolution by around 2-fold. Moreover, it enabled the improvement in imaging SNR for both major vessels and capillaries, and realized the well-preserved blood vessels' edges simultaneously, which surpasses conventional Richardson-Lucy BD algorithm. The reported results indicate that the BDTV algorithm potentially facilitate PAOM in extracting retinal pathophysiological information by enhancing in vivo imaging quality without physically modifying PAOM's optical configuration.

Introduction and Overview on Myopia: A Clinical Perspective

“…This modality has been used before to image the posterior pole of the eye in vitro and in animal models in vivo. This can also be used in concurrence with angiography, measuring oxygen saturation and pigment imaging [151]. However, there are some limitations pertaining to this modality notwithstanding moderate depth resolution, pure optical absorption sensing, need for contact detection with ultrasound sensor, and a relatively long acquisition time.…”

Imaging in myopia: potential biomarkers, current challenges and future developments

“…The technique is of interest because it may fill the gap between OCT and US in terms of penetration depth. Indeed, photoacoustic imaging systems have been described that image the posterior pole of the eye in vitro and in animal models in vivo, which can also be used for angiography, measurement of oxygen saturation and pigment imaging 98. Disadvantages of photoacoustic imaging include moderate depth resolution, pure optical absorption sensing, need for contact detection with the ultrasound sensor and relatively long acquisition time.…”

Imaging in Myopia

“…This modality has been used before to image the posterior pole of the eye in vitro and in animal models in vivo. This can also be used in concurrence with angiography, measuring oxygen saturation and pigment imaging [126]. However, there are some limitation pertaining to this modality notwithstanding moderate depth resolution, pure optical absorption sensing, need for contact detection with ultrasound sensor, and a relatively long acquisition time.…”