title: Cerebrospinal fluid drainage through the diploic and spinal epidural veins.
abstract: The aim of this study was to quantitatively evaluate the function of the cranial diploic and spinal epidural veins as cerebrospinal fluid (CSF) drainage pathways by measuring lipocalin-type prostaglandin D synthase (PGDS) and cystatin C (CysC) dissolved in the blood of these veins. This was a prospective study involving 51 consecutive patients, 31 males and 20 females, who underwent 41 cranial and 10 spinal surgeries. Intraoperatively, peripheral venous blood and diploic venous blood, or peripheral venous blood and spinal epidural venous blood samples were simultaneously collected and immediately centrifuged. For all samples, dissolved albumin (for reference), PGDS and CysC were measured using an enzyme-linked immunosorbent assay. The diploic vein/peripheral vein ratios in five cranial locations and epidural vein/peripheral vein ratios were calculated and statistically evaluated for the three biomarkers. For PGDS, the diploic vein/peripheral vein ratio was significantly increased in the frontal (P = 0.011), temporal (P = 0.028), parietal (P = 0.046) and skull base (P = 0.039), while it did not reach statistical significance for CysC. For patients older than 45 years, the diploic vein/peripheral vein ratio for PGDS was significantly decreased in the frontal region (P = 0.028), and the epidural vein/peripheral vein ratio for CysC was significantly decreased (P = 0.014). These results show that the diploic veins constitute CSF drainage pathways with heterogeneous functional intensity at different cranial locations. Compared with the diploic veins, spinal epidural veins seem to drain less CSF. The cranial diploic and spinal epidural veins may jointly function as an alternative, age-related trans-dural CSF drainage system.
authors.affiliation: Department of Neurological Surgery, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tsutsumi
authors.affiliation: Department of Neurological Surgery, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Ikuko
authors.initials: I
authors.lastname: Ogino
authors.affiliation: Department of Neurological Surgery, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Miyajima
authors.affiliation: Department of Neurological Surgery, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Ito
authors.affiliation: Department of Neurological Surgery, Juntendo University School of Medicine, Tokyo, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Arai
authors.affiliation: Department of Neurological Surgery, Juntendo University Urayasu Hospital, Urayasu, Chiba, Japan.
authors.forename: Yukimasa
authors.initials: Y
authors.lastname: Yasumoto
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002550:Cerebral Veins; D002555:Cerebrospinal Fluid / Q000502:physiology*; D065634:Cerebrospinal Fluid Leak / Q000503:physiopathology*; D055316:Cystatin C / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D054834:Lipocalins / Q000097:blood; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D015230:Prostaglandin D2 / Q000097:blood; D012886:Skull / Q000601:surgery; D013131:Spine / Q000098:blood supply* / Q000601:surgery; D014680:Veins
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D054834:Lipocalins; D015230:Prostaglandin D2
keywords: CSF drainage; biomarkers; diploic veins; spinal epidural venous plexus