{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T10:27:53Z","timestamp":1788344873797,"version":"build-2803163510"},"reference-count":41,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,2,15]],"date-time":"2023-02-15T00:00:00Z","timestamp":1676419200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Emit Imaging"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Imaging"],"abstract":"<jats:p>Unwanted proteins and metabolic waste in cerebral spinal fluid are cleared from the brain by meningeal and nasal lymphatics and the perineural sheath of cranial nerves; however, the distribution and clearance of cerebral spinal fluid (CSF) along the subarachnoid space of the entire spinal cord is not fully understood. Cryo-fluorescence tomography (CFT) was used to follow the movement of tracers from the ventricular system of the brain down through the meningeal lining of the spinal cord and out to the spinal lymphatic nodes. Isoflurane-anesthetized mice were infused into the lateral cerebroventricle with 5.0 \u00b5L of quantum dots [QdotR 605 ITKTM amino (PEG)] over two mins. Mice were allowed to recover (ca 2\u20133 min) and remained awake and ambulatory for 5, 15, 30, 60, and 120 min after which they were euthanized, and the entire intact body was frozen at \u221280\u00b0. The entire mouse was sectioned, and white light and fluorescent images were captured after each slice to produce high resolution three-dimensional volumes. Tracer appeared throughout the ventricular system and central canal of the spinal cord and the entire subarachnoid space of the CNS. A signal could be visualized in the nasal cavity, deep cervical lymph nodes, thoracic lymph nodes, and more superficial submandibular lymph nodes as early as 15 min post infusion. A fluorescent signal could be visualized along the dorsal root ganglia and down the proximal extension of the spinal nerves of the thoracic and lumbar segments at 30 min. There was a significant accumulation of tracer in the lumbar and sacral lymph nodes between 15\u201360 min. The dense fluorescent signal in the thoracic vertebrae noted at 5- and 15-min post infusion was significantly reduced by 30 min. Indeed, all signals in the spinal cord were ostensibly absent by 120 min, except for trace amounts in the coccyx. The brain still had some residual signal at 120 min. These data show that Qdots with a hydrodynamic diameter of 16\u201320 nm rapidly clear from the brain of awake mice. These data also clearly demonstrate the rapid distribution and efflux of traces along a major length of the vertebral column and the potential contribution of the spinal cord in the clearance of brain waste.<\/jats:p>","DOI":"10.3390\/jimaging9020045","type":"journal-article","created":{"date-parts":[[2023,2,16]],"date-time":"2023-02-16T02:28:27Z","timestamp":1676514507000},"page":"45","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Whole CNS 3D Cryo-Fluorescence Tomography Shows CSF Clearance along Nasal Lymphatics, Spinal Nerves, and Lumbar\/Sacral Lymph Nodes"],"prefix":"10.3390","volume":"9","author":[{"given":"Christian","family":"Stokes","sequence":"first","affiliation":[{"name":"EMIT Imaging, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eli F","family":"White","sequence":"additional","affiliation":[{"name":"EMIT Imaging, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Steve","family":"Toddes","sequence":"additional","affiliation":[{"name":"EMIT Imaging, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicole","family":"Bens","sequence":"additional","affiliation":[{"name":"Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8876-4544","authenticated-orcid":false,"given":"Praveen","family":"Kulkarni","sequence":"additional","affiliation":[{"name":"Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9744-5214","authenticated-orcid":false,"given":"Craig F","family":"Ferris","sequence":"additional","affiliation":[{"name":"Center for Translational NeuroImaging, Northeastern University, Boston, MA 02115, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,15]]},"reference":[{"key":"ref_1","first-page":"454","article-title":"The Glymphatic Pathway: Waste Removal from the CNS via Cerebrospinal Fluid Transport","volume":"23","author":"Benveniste","year":"2017","journal-title":"Neurosci. A Rev. J. Bringing Neurobiol. Neurol. Psychiatry"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2429","DOI":"10.1007\/s00018-020-03706-5","article-title":"Cerebrospinal fluid outflow: A review of the historical and contemporary evidence for arachnoid villi, perineural routes, and dural lymphatics","volume":"78","author":"Proulx","year":"2021","journal-title":"Cell. Mol. Life Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"269","DOI":"10.1111\/j.1750-3639.1992.tb00703.x","article-title":"Drainage of brain extracellular fluid into blood and deep cervical lymph and its immunological significance","volume":"2","author":"Cserr","year":"1992","journal-title":"Brain Pathol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1111\/j.1365-2990.2007.00926.x","article-title":"Solutes, but not cells, drain from the brain parenchyma along basement membranes of capillaries and arteries: Significance for cerebral amyloid angiopathy and neuroimmunology","volume":"34","author":"Carare","year":"2008","journal-title":"Neuropathol. Appl. Neurobiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"668","DOI":"10.1073\/pnas.1914017117","article-title":"Imaging the effect of the circadian light-dark cycle on the glymphatic system in awake rats","volume":"117","author":"Cai","year":"2020","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"118420","DOI":"10.1016\/j.neuroimage.2021.118420","article-title":"Sleep-related and diurnal effects on brain diffusivity and cerebrospinal fluid flow","volume":"241","author":"Tuura","year":"2021","journal-title":"NeuroImage"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"863","DOI":"10.1093\/brain\/awaa443","article-title":"Sleep deprivation impairs molecular clearance from the human brain","volume":"144","author":"Eide","year":"2021","journal-title":"Brain"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1186\/1743-8454-1-2","article-title":"Evidence of connections between cerebrospinal fluid and nasal lymphatic vessels in humans, non-human primates and other mammalian species","volume":"1","author":"Johnston","year":"2004","journal-title":"Cereb. Fluid Res."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"480","DOI":"10.1111\/j.1365-2990.1993.tb00476.x","article-title":"CSF drains directly from the subarachnoid space into nasal lymphatics in the rat. Anatomy, histology and immunological significance","volume":"19","author":"Kida","year":"1993","journal-title":"Neuropathol. Appl. Neurobiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"e44278","DOI":"10.7554\/eLife.44278","article-title":"Anatomical basis and physiological role of cerebrospinal fluid transport through the murine cribriform plate","volume":"8","author":"Norwood","year":"2019","journal-title":"Elife"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"991","DOI":"10.1084\/jem.20142290","article-title":"A dural lymphatic vascular system that drains brain interstitial fluid and macromolecules","volume":"212","author":"Aspelund","year":"2015","journal-title":"J. Exp. Med."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1038\/s41586-019-1419-5","article-title":"Meningeal lymphatic vessels at the skull base drain cerebrospinal fluid","volume":"572","author":"Ahn","year":"2019","journal-title":"Nature"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1007\/BF00645050","article-title":"Distribution of intraventricularly injected horseradish peroxidase in cerebrospinal fluid compartments of the rat spinal cord","volume":"270","author":"Cifuentes","year":"1992","journal-title":"Cell Tissue Res."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1007\/BF00690695","article-title":"Penetration and removal of horseradish peroxidase injected into the cerebrospinal fluid: Role of cerebral perivascular spaces, endothelium and microglia","volume":"27","author":"Wagner","year":"1974","journal-title":"Acta Neuropathol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"12924","DOI":"10.1038\/s41598-017-13455-4","article-title":"The ultrastructure of spinal cord perivascular spaces: Implications for the circulation of cerebrospinal fluid","volume":"7","author":"Lam","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2492","DOI":"10.1084\/jem.20190351","article-title":"Clearance of cerebrospinal fluid from the sacral spine through lymphatic vessels","volume":"216","author":"Ma","year":"2019","journal-title":"J. Exp. Med."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"R909","DOI":"10.1152\/ajpregu.2001.281.3.R909","article-title":"Spinal and cranial contributions to total cerebrospinal fluid transport","volume":"281","author":"Mollanji","year":"2001","journal-title":"Am. J. Physiol. Regul. Integr. Comp. Physiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"763780","DOI":"10.3389\/fnins.2021.763780","article-title":"Do We Swallow the Waste From Our Brain?","volume":"15","author":"Leaston","year":"2021","journal-title":"Front. Neurosci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1577","DOI":"10.1111\/j.1476-5381.2010.00872.x","article-title":"Animal research: Reporting in vivo experiments: The ARRIVE guidelines","volume":"160","author":"Kilkenny","year":"2010","journal-title":"Br. J. Pharmacol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"710","DOI":"10.7150\/thno.19154","article-title":"General Anesthesia Inhibits the Activity of the \u201cGlymphatic System\u201d","volume":"8","author":"Gakuba","year":"2018","journal-title":"Theranostics"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"500","DOI":"10.1016\/j.tins.2019.05.001","article-title":"Regulation of the Blood-Brain Barrier by Circadian Rhythms and Sleep","volume":"42","author":"Cuddapah","year":"2019","journal-title":"Trends Neurosci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"13740","DOI":"10.1038\/s41598-022-15109-6","article-title":"Cortical waste clearance in normal and restricted sleep with potential runaway tau buildup in Alzheimer\u2019s disease","volume":"12","author":"Tekieh","year":"2022","journal-title":"Sci. Rep."},{"key":"ref_23","first-page":"100025","article-title":"Aberrant waste disposal in neurodegeneration: Why improved sleep could be the solution","volume":"2","author":"Wafford","year":"2021","journal-title":"Cereb. Circ.-Cogn. Behav."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Massey, A., Boag, M.K., Magnier, A., Bispo, D.P., Khoo, T.K., and Pountney, D.L. (2022). Glymphatic System Dysfunction and Sleep Disturbance May Contribute to the Pathogenesis and Progression of Parkinson\u2019s Disease. Int. J. Mol. Sci., 23.","DOI":"10.3390\/ijms232112928"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"624690","DOI":"10.3389\/fnins.2021.624690","article-title":"Rethinking the Conditions and Mechanism for Glymphatic Clearance","volume":"15","author":"Ferris","year":"2021","journal-title":"Front. Neurosci."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1016\/0031-9384(92)90188-8","article-title":"The circadian rhythm of body temperature","volume":"51","author":"Refinetti","year":"1992","journal-title":"Physiol. Behav."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"379","DOI":"10.1126\/science.1195262","article-title":"Temperature as a universal resetting cue for mammalian circadian oscillators","volume":"330","author":"Buhr","year":"2010","journal-title":"Science"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"539","DOI":"10.4161\/cc.23670","article-title":"Body temperature cycles: Gatekeepers of circadian clocks","volume":"12","author":"Morf","year":"2013","journal-title":"Cell Cycle"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"307","DOI":"10.3389\/fnins.2014.00307","article-title":"Brain temperature and its fundamental properties: A review for clinical neuroscientists","volume":"8","author":"Wang","year":"2014","journal-title":"Front. Neurosci."},{"key":"ref_30","first-page":"989487","article-title":"Brain temperature: Physiology and pathophysiology after brain injury","volume":"2012","author":"Mrozek","year":"2012","journal-title":"Anesthesiol. Res. Pract."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"701","DOI":"10.1007\/s00360-009-0352-6","article-title":"Body and brain temperature coupling: The critical role of cerebral blood flow","volume":"179","author":"Zhu","year":"2009","journal-title":"J. Comp. Physiol. B"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"35","DOI":"10.1186\/2045-8118-10-35","article-title":"In vivo imaging of lymphatic drainage of cerebrospinal fluid in mouse","volume":"10","author":"Mathieu","year":"2013","journal-title":"Fluids Barriers CNS"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1080\/01616412.2000.11741064","article-title":"Study of cerebrospinal fluid flow dynamics in TGF-beta 1 induced chronic hydrocephalic mice","volume":"22","author":"Moinuddin","year":"2000","journal-title":"Neurol. Res."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1007\/s00401-018-1916-x","article-title":"Rapid lymphatic efflux limits cerebrospinal fluid flow to the brain","volume":"137","author":"Ma","year":"2019","journal-title":"Acta Neuropathol."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1186\/s12987-018-0098-1","article-title":"Fluid outflow in the rat spinal cord: The role of perivascular and paravascular pathways","volume":"15","author":"Liu","year":"2018","journal-title":"Fluids Barriers CNS"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"277","DOI":"10.1679\/aohc.61.277","article-title":"Lymphatic drainage of the cerebrospinal fluid from monkey spinal meninges with special reference to the distribution of the epidural lymphatics","volume":"61","author":"Miura","year":"1998","journal-title":"Arch. Histol. Cytol."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"3645","DOI":"10.1084\/jem.20170391","article-title":"Development and plasticity of meningeal lymphatic vessels","volume":"214","author":"Antila","year":"2017","journal-title":"J. Exp. Med."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"4594","DOI":"10.1038\/s41467-019-12568-w","article-title":"Anatomy and function of the vertebral column lymphatic network in mice","volume":"10","author":"Jacob","year":"2019","journal-title":"Nat. Commun."},{"key":"ref_39","first-page":"e12030","article-title":"Intrathecal (99m)Tc-DTPA imaging of molecular passage from lumbar cerebrospinal fluid to brain and periphery in humans","volume":"12","author":"Verma","year":"2020","journal-title":"Alzheimer\u2019s Dement."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"399","DOI":"10.3325\/cmj.2014.55.399","article-title":"Cerebrospinal fluid outflow along lumbar nerves and possible relevance for pain research: Case report and review","volume":"55","author":"Bechter","year":"2014","journal-title":"Croat. Med. J."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"317","DOI":"10.2310\/7290.2010.00049","article-title":"Integrated lymphography using fluorescence imaging and magnetic resonance imaging in intact mice","volume":"10","author":"Inoue","year":"2011","journal-title":"Mol. Imaging"}],"container-title":["Journal of Imaging"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2313-433X\/9\/2\/45\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T18:36:43Z","timestamp":1760121403000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2313-433X\/9\/2\/45"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,2,15]]},"references-count":41,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2023,2]]}},"alternative-id":["jimaging9020045"],"URL":"https:\/\/doi.org\/10.3390\/jimaging9020045","relation":{"has-preprint":[{"id-type":"doi","id":"10.20944\/preprints202211.0171.v1","asserted-by":"object"}]},"ISSN":["2313-433X"],"issn-type":[{"value":"2313-433X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,2,15]]}}}