Blockade of lymphatic drainage to deep cervical lymph nodes impacts CSF flow and brain morphometry

The altered CNS fluid flow dynamics and homeostasis mechanisms in response to blockade of lymphatic drainage to deep cervical lymph nodes (dcLN) is poorly understood. We used multi-modality MRI and computational fluid dynamics approach to study the same in rats with electrocauterized afferent lymphatic vessels of dcLN. The brain morphometry of Cauterized-dcLN rats showed localized volume expansion in Pons, Hippocampus and Corpus-callosum, while glymphatic speed maps showed hyperdynamic CSF flow in ambient and quadrigeminal cisterns. These results clearly show that the blockade of CSF drainage to dcLN alters CNS fluid homeostasis/flow dynamics, long-term may result in waste accumulation and neurodegeneration.