Table 3.

In vivo models of CSF absorption.

Method	Description	Year/Reference
Variable rate infusion	Infusion of aCSF into the lateral ventricle at a known flow rate causes CSF pressure to rise to a plateau level. The resistance to CSF absorption (mmH2O.min/μl) is calculated from the gradient of CSF pressure at plateau level against the infusion rate (Fig. 3b).	1987 [127]
Hyperspectral imaging of lymphatic drainage	Quantum dot 655 fluorescent particles are injected into the CSF of the Cisterna magna and visualised by in vivo hyperspectral imaging at varying time points. A quantum dot signal, detected in submandibular lymph nodes, determines the site of CSF absorption.	2013 [48]
High resolution stereomicroscopy	Lymphatic-reporter mice characterised the anatomical routes and dynamics of CSF outflow. This non-invasive imaging technique quantified the transport of tracers to the blood and lymph nodes following injection into the lateral ventricles.	2017 [128]