一种新的显示蛛网膜下腔与颈部淋巴管交通的研究方法：Microfil^TM蛛网膜下腔注射

目的采用一种新的方法在形态学上证实兔和大鼠蛛网膜下腔与颈部淋巴系统相通。方法在刚死亡的兔和大鼠枕大池内注射Microfil^TM,注射2h后在手术显微镜下观察灌注物质在蛛网膜下腔及头颈部淋巴管内的分布。结果Microfil^TM在兔和大鼠枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色而呈黄色,经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管。两种动物的Microfil^TM染色范围没有明显差别。结论Microfil^TM蛛网膜下腔注射是显示蛛网膜下腔与颈部淋巴系统相通的一种有效且便捷的方法。     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

兔脑脊液经嗅觉通路回流到淋巴系统的形态学观察

目的 在形态学上证实兔颅底蛛网膜下腔经嗅觉通路与颈部淋巴系统相通,脑脊液经此途径回流到淋巴系统.方法 采用在兔枕大池内注射Microfil 的方法,在大体和光镜下观察灌注物质的分布.结果 显微镜下观察见Microfil 在枕大池、矢状窦、嗅球、筛板区域聚集分布,穿过筛板,使嗅黏膜淋巴管明显染色呈黄色,并经鼻咽部淋巴管回流到双侧颈浅和颈深淋巴管;光镜下见Microfil 沿嗅神经走行,广泛分布在嗅黏膜的淋巴管内.结论 在脑脊液与颈部淋巴系统之间存在有经颅底-筛板-嗅黏膜的嗅觉通路的解剖回流途径,对于中枢神经系统免疫性疾病、脑脊液循环的调节有重要意义.     

Olfactory route for cerebrospinal fluid drainage into the cervical lymphatic system in a rabbit experimental model

The present study analyzed the anatomical association between intracranial subarachnoid space and the cervical lymphatic system. X-ray contrast medium and Microfil (Microfil compounds fill and opacify microvascular and other spaces of non-surviving animals and post-mortem tissue under physiological injection pressure) were injected into the cisterna magna of the rabbit, and perineural routes of cerebrospinal fluid outflow into the lymphatic system were visualized. Under a surgical operating microscope, Microfil was found within the subarachnoid space and along the olfactory nerves. At the nasal mucosa, a lymphatic network was identified near the olfactory nerves, which crossed the nasopharyngeal region and finally emptied into the superficial and deep cervical lymph nodes. Under a light microscope, Microfil was visible around the olfactory nerves and within lymphatic vessels. These results suggested that cerebrospinal fluid drained from the subarachnoid space along the olfactory nerves to nasal lymphatic vessels, which in turn, emptied into the cervical lymph nodes. This anatomical route, therefore, allowed connection between the central nervous system and the lymphatic system.     

Dynamic properties of lymphatic pathways for the absorption of cerebrospinal fluid

To study the dynamics of the outflow of cerebrospinal fluid (CSF) into the cervical lymphatic system, X-ray contrast medium or Indian ink was infused into the cisterna magna of rats at moderately increased intracranial pressure (40–50 mm Hg). In the first series of experiments, while the contrast medium was being infused, the animal’s head was examined using X-ray-microscopy (× 4–20 direct magnification radiography) and conventional radiography. Within the first minutes of infusion, the flow of CSF was directed from the posterior fossa to the olfactory bulb. Reaching the cribriform plate approximately 7 min after starting the infusion, the contrast medium leaked into the nasal cavities. Some minutes later, it opacified the subarachnoid space (SAS) of the optic nerve, the perilymphatic space of the inner ear, the cortical SAS, and the transverse sinuses. Leakage from the optic nerve SAS into the orbit was seen after 30 min infusion. In the second series of experiments, the Indian ink was infused after microsurgical exposure of the cervical lymph vessels. During the infusion the cervical lymph ducts were observed microscopically (× 40 magnification). Single dye particles draining through the cervical lymph ducts appeared 20 min after the start of cisternal infusion. Their transport was rapid, and dependent on the respiratory cycle: during inspiration the particles moved at a speed of 10–20 mm/s, during expiration the movement stopped. Thus, rapid kinetics are demonstrated for the outflow of CSF and particles from the SAS into the cervical lymphatics. Received: 11 February 1997 / Revised, accepted: 14 April 1997     

CSF drains directly from the subarachnoid space into nasal lymphatics in the rat. Anatomy, histology and immunological significance

Cerebrospinal fluid (CSF) drainage pathways from the rat brain were investigated by the injection of 50 μl Indian ink into the cisterna magna. The distribution of the ink, as it escaped from the cranial CSF space, was documented in 2 mm thick slices of brain and skull cleared in cedar wood oil and in decalcified paraffin sections. Following injection of the ink, deep cervical lymph nodes were selectively blackened within 30 min and lumbar para-aortic nodes within 6 h. Within the cranial cavity, carbon particles accumulated in the basal cisterns but were also distributed in the paravascular spaces around the middle cerebral arteries and the nasal-olfactory artery. Carbon particles in the subarachnoid space beneath the olfactory bulbs drained directly into discrete channels which passed through the cribriform plate and into lymphatics in the nasal submucosa. Although ink was distributed along the subarachnoid space of the optic nerves and entered the cochlea, the nasal route was the only direct connection between cranial CSF and lymphatics. Arachnoid villi associated with superior and inferior sagittal sinuses were identified and a minor amount of drainage of ink into dural lymphatics was also observed. This study demonstrates the direct drainage of cerebrospinal fluid through the cribriform plate in anatomically defined channels which connect with the nasal lymphatics. Such a pathway is compatible with the observed rapidity of the bulk flow drainage of CSF in the rat, accords with the known specificity of immunological reactions to antigens injected into brain tissue, and may also serve as a route for drainage for lymphocytes and macrophages from the brain to the regional cervical lymph nodes.     

Chicken arachnoid granulations: a new model for cerebrospinal fluid absorption in man

Cerebrospinal fluid (CSF) absorption was investigated chicken and rat using infusion tests into the cisterna magna. Data were analysed according to a mathematical model by Johnson et al. Results in rat predicted a predominant lymphatic mechanism, which was confirmed by rapid outflow of X-ray contrast media into the olfactoric mucosa. In contrast, dynamics measurements suggested CSF drainage via arachnoid granulations in chicken. CSF spaces along the optic nerve were contrasted radiographically resulting in venous drainage. Electron microscopically, villus-like structures were found at the distal optic nerve connecting the subarachnoid space with accompanying veins, resembling human arachnoid granulations. We hypothesize that CSF absorption through arachnoid villi in microsmatic chicken reflects the situation in man very well.