Evaluation of zebrafish brain development using optical coherence tomography

Abstract

The zebrafish is a well-established model system used to study and understand various human biological processes. The present study used OCT to investigate growth of the adult zebrafish brain. Twenty zebrafish were studied, using their standard lengths as indicators of their age. Zebrafish brain aging was evaluated by analyzing signal attenuation rates and texture features in regions of interest (ROIs). Optical scattering originates from light interaction with biological structures. During development, the zebrafish brain gains cells. Signal attenuation rate, therefore, increases with increasing zebrafish brain age. This study's analyses of texture features could not identify aging in zebrafish brain. These results, therefore, indicated that the OCT signal attenuation rate can indicate zebrafish brain aging, and its analysis provides a more effective means of observing zebrafish brain aging than texture features analysis. Using OCT system could further increase the technique's potential for recognition and monitoring of zebrafish brain development.

Optical Coherence Tomography for Brain Imaging and Developmental Biology

“…Development of brain morphology has been visualized with OCT in small animal models, such as Xenopus [122], zebrafish [40, 123] and fetal mouse [124]. Basic structures of the early embryonic brain, including diencephalic ventricles, midbrain and hindbrain, were revealed within 24 hours post fertilization in zebrafish [40].…”

“…Basic structures of the early embryonic brain, including diencephalic ventricles, midbrain and hindbrain, were revealed within 24 hours post fertilization in zebrafish [40]. Morphology progression of more sophisticated brain structures including the olfactory bulb, telencephalon, cerebellum, medulla, tectum opticum and optic commissure, were visualized in adult zebrafish using OCT [123, 125, 126], showing progression of brain morphology. Optical attenuation in zebrafish brain was quantified, demonstrating a negative linear correlation between optical signal attenuation and brain aging [123].…”

In vivo three-dimensional characterization of the adult zebrafish brain using a 1325 nm spectral-domain optical coherence tomography system with the 27 frame/s video rate

“…However, most of the work was performed by using early-stage zebrafish [21]. More recently, two cases were reported that could capture part of the features of adult zebrafish brain based on OCT [22,23]. However, due to the slow imaging speed and limited penetration depth, a comprehensive in vivo 3D characterization of the whole adult zebrafish brain has never been accomplished.…”

Internal physiology of live krill revealed using new aquaria techniques and mixed optical microscopy and optical coherence tomography (OCT) imaging techniques

“…OCT has been used to image various biological processes in zebra fish (Danio rerio), e.g. brain growth (Lin et al, 2013), and eye structure (Divakar Rao et al, 2006). Recently, OCT has been used to image tissue structure in previously frozen krill samples (Bellini et al, 2014) to a depth of c. 2 mm, with a resolution of c. 12 μm.…”