  An in-vitro cell culture system is used for biological discoveries and
hypothesis-driven research on a particular cell type to understand mechanistic
or test pharmaceutical drugs. Conventional in-vitro cultures have been applied
to primary cells and immortalised cell lines plated on 2D surfaces. However,
they are unreliable in complex physiological environments and can not always
predict in-vivo behaviour correctly. Organoids are multicellular spheroids of a
primary donor or stem cells that are replaced in vitro cell culture systems and
are widely used in biological, biomedical and translational studies. Native
heterogeneity, microanatomy, and functionality of an organ or diseased tissue
can be represented by three-dimensional in-vitro tissue models such as
organoids. Organoids are essential in in-vitro models for drug discovery and
personalised drug screening. Many imaging artefacts such as organoid occlusion,
overlap, out-of-focus spheroids and considerable heterogeneity in size cause
difficulty in conventional image processing. Despite the power of organoid
models for biology, their size and shape have mostly not been considered. Drug
responses depend on dynamic changes in individual organoid morphology, number
and size, which means differences in organoid shape and size, movement through
focal planes, and live-cell staining with limited options cause challenges for
drug response and growth analysis. This study primarily introduces the
importance of the role of the organoid culture system in different disciplines
of medical science and various scopes of utilising organoids. Then studies the
challenges of operating organoids, followed by reviewing image analysis systems
or platforms applied to organoids to address organoid utilising challenges.
