# ChOP-CT: quantitative morphometrical analysis of the Hindbrain Choroid Plexus by X-ray micro-computed tomography

## TL;DR

ChOP-CT is a new tool that uses X-ray imaging to study the shape and structure of the Hindbrain Choroid Plexus in mouse embryos, helping researchers understand its role in brain development and disease.

## Contribution

ChOP-CT introduces a noninvasive, quantitative method for analyzing the 3D morphology of the Hindbrain Choroid Plexus in mouse embryos.

## Key findings

- ChOP-CT reliably quantifies volume, surface area, and shape of the Hindbrain Choroid Plexus from embryonic day 13.5 onwards.
- The method detects alterations in the Hindbrain Choroid Plexus in various mutant mouse embryos.
- ChOP-CT enables unbiased and automated analysis, facilitating the study of genes and mechanisms related to disease onset.

## Abstract

The Hindbrain Choroid Plexus is a complex, cerebrospinal fluid-secreting tissue that projects into the 4th vertebrate brain ventricle. Despite its irreplaceability in the development and homeostasis of the entire central nervous system, the research of Hindbrain Choroid Plexus and other Choroid Plexuses has been neglected by neuroscientists for decades. One of the obstacles is the lack of tools that describe the complex shape of the Hindbrain Choroid Plexus in the context of brain ventricles. Here we introduce an effective tool, termed ChOP-CT, for the noninvasive, X-ray micro-computed tomography-based, three-dimensional visualization and subsequent quantitative spatial morphological analysis of developing mouse Hindbrain Choroid Plexus. ChOP-CT can reliably quantify Hindbrain Choroid Plexus volume, surface area, length, outgrowth angle, the proportion of the ventricular space occupied, asymmetries and general shape alterations in mouse embryos from embryonic day 13.5 onwards. We provide evidence that ChOP-CT is suitable for the unbiased evaluation and detection of the Hindbrain Choroid Plexus alterations within various mutant embryos. We believe, that thanks to its versatility, quantitative nature and the possibility of automation, ChOP-CT will facilitate the analysis of the Hindbrain Choroid Plexus in the mouse models. This will ultimately accelerate the screening of the candidate genes and mechanisms involved in the onset of various Hindbrain Choroid Plexus-related diseases.

The online version contains supplementary material available at 10.1186/s12987-023-00502-8.