Fig. 5
From: Anatomy and function of the vertebral column lymphatic network in mice
Epidural and dural lymphatic circuits of the spine. a 2D-single frontal image slice (2 µm thick) of the cervical vertebral column with enhanced brightness to reveal PROX1-expressing nuclei and spinal cord (SC), meninges including pia mater (Pi), arachnoid (A) and dura mater (DM), the epidural space (ES), and the ligamentum flavum (LF). A color-coded segmentation of layers around the spinal cord shows the meningeal layers in purple and the dura mater plus the epidural space in green. b–d 3D-reconstruction of frontal images of the cervical vertebral column with color-coded layers: the arachnoid and dura mater in purple (b); the dura mater and epidural space in green (c); combined layer marks showing the arachnoid in purple, the dura mater in white, and the epidural space in green (d), spatial orientation (D: dorsal, L: lateral, V: ventral). A noticeable LV network fills the epidural space (green) while dura mater LVs (white) are mainly restricted to DRGs (white arrows) and few branches on each side of the dorsal and ventral midline. e 3D-reconstruction of lateral images of the thoracic vertebral column with color-coded layers illustrated in (d). Blue dotted-lines: bilateral DRGs; salmon arrows: intervertebral LVs; Red asterisk: vertebral ventral body. Vx: vertebra x, Vx + 1: vertebra x + 1. f Schematic representation of the lymphatic vasculature in the thoracic vertebral column. LVs are present in the epidural space (green) around the spinal cord and in the dura mater (purple). Extravertebral LVs extend dorsal processes (blue) and ventral connections with sympathetic ganglia (SG, deep blue) and the thoracic duct (TD, light blue). Blue arrowheads; exit points of vertebral lymphatic circuits; Blue dots: connections with extravertebral lymphatic networks; Black asterisk: vertebral ventral body; DRG: dorsal root ganglia; FJ: facet joint; LF: ligamentum flavum; SC: spinal cord; SG: sympathetic ganglia. Scale bars: 300 µm (a–e)
