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World Neurosurgery Dec 2023Collection of cerebrospinal fluid (CSF) in the subdural compartment is a major cause of postoperative morbidity, especially for posterior fossa surgeries. Arachnoid...
BACKGROUND
Collection of cerebrospinal fluid (CSF) in the subdural compartment is a major cause of postoperative morbidity, especially for posterior fossa surgeries. Arachnoid closure techniques, including suturing of the arachnoid and use of synthetic sealants, have been described in the literature. However, they are not always feasible or effective and have not been universally adopted.
METHODS
We describe the technique of arachnoid welding for a case of brainstem cavernoma. This is a simple, cost-effective, and easily reproducible technique using readily available bipolar cautery kept at a low-current setting. At the end of surgery, the arachnoid leaflets are closely approximated, and bipolar cautery is used to seal the edges together. An illustrative video shows the technical nuances of this procedure. This technique can also be applied for arachnoid closure at other cranial and spinal sites.
RESULTS
Arachnoid closure can act as an effective natural barrier to keep CSF in its physiological subarachnoid compartment. It provides an additional barrier to prevent CSF leak. It also prevents morbidity associated with adhesions and arachnoiditis. Proper closure of arachnoid makes durotomy during repeat surgery much easier and avoids injury to the underlying pia. A brief review of related literature shows the benefits of closing the arachnoid before dural closure and the different techniques that have been described so far.
CONCLUSIONS
The arachnoid welding technique has a wide application, is easy to learn, and can be used especially for posterior fossa surgeries in which rates of CSF leak are the highest.
Topics: Humans; Welding; Postoperative Complications; Cerebrospinal Fluid Leak; Arachnoid; Neurosurgical Procedures; Dura Mater
PubMed: 37739172
DOI: 10.1016/j.wneu.2023.09.047 -
Nature Communications Sep 2023Meninges cover the surface of the brain and spinal cord and contribute to protection and immune surveillance of the central nervous system (CNS). How the meningeal...
Meninges cover the surface of the brain and spinal cord and contribute to protection and immune surveillance of the central nervous system (CNS). How the meningeal layers establish CNS compartments with different accessibility to immune cells and immune mediators is, however, not well understood. Here, using 2-photon imaging in female transgenic reporter mice, we describe VE-cadherin at intercellular junctions of arachnoid and pia mater cells that form the leptomeninges and border the subarachnoid space (SAS) filled with cerebrospinal fluid (CSF). VE-cadherin expression also marked a layer of Prox1 cells located within the arachnoid beneath and separate from E-cadherin arachnoid barrier cells. In vivo imaging of the spinal cord and brain in female VE-cadherin-GFP reporter mice allowed for direct observation of accessibility of CSF derived tracers and T cells into the SAS bordered by the arachnoid and pia mater during health and neuroinflammation, and detection of volume changes of the SAS during CNS pathology. Together, the findings identified VE-cadherin as an informative landmark for in vivo imaging of the leptomeninges that can be used to visualize the borders of the SAS and thus potential barrier properties of the leptomeninges in controlling access of immune mediators and immune cells into the CNS during health and neuroinflammation.
Topics: Female; Animals; Mice; Pia Mater; Neuroinflammatory Diseases; Central Nervous System; Arachnoid; Cadherins; Inflammation; Mice, Transgenic
PubMed: 37730744
DOI: 10.1038/s41467-023-41580-4 -
Oncology Letters Oct 2023Central nervous system (CNS) malignant melanomas are rare tumors of the CNS that are thought to arise from aberrant changes in melanocytes of the neural crest or...
Central nervous system (CNS) malignant melanomas are rare tumors of the CNS that are thought to arise from aberrant changes in melanocytes of the neural crest or melanocytic elements of the pia mater during early embryonic development. As a rare type of CNS malignant melanoma, only a few cases of primary malignant melanoma in the spinal canal have been reported thus far. The majority of these studies have reported on the diagnosis, radiographic features and gross total resection of primary spinal canal malignant melanoma; however, the prognosis and ideal treatment of patients with residual tumors remain elusive. The current study presented the rare case of a patient with primary malignant melanoma originating from the thoracic spinal canal, without any history of irradiation exposure and with an incompletely resected tumor. Disease-free survival of >2.5 years was observed in this patient who was treated with concurrent chemoradiotherapy followed by adjuvant chemotherapy with temozolomide and bevacizumab.
PubMed: 37664668
DOI: 10.3892/ol.2023.14020 -
BioRxiv : the Preprint Server For... Aug 2023The recent characterization of the glymphatic system and meningeal lymphatics has re-emphasized the role of the meninges in facilitating CSF transport and clearance....
BACKGROUND
The recent characterization of the glymphatic system and meningeal lymphatics has re-emphasized the role of the meninges in facilitating CSF transport and clearance. Here, we characterize small and large CSF solute distribution patterns along the intracranial and surface meninges in neonatal rodents and compare our findings to a rodent model of intraventricular hemorrhage-posthemorrhagic hydrocephalus. We also examine CSF interactions with the tela choroidea and its pial invaginations into the choroid plexuses of the lateral, third, and fourth ventricles.
METHODS
1.9-nm gold nanoparticles, 15-nm gold nanoparticles, or 3 kDa Red Dextran Tetramethylrhodamine constituted in aCSF were infused into the right lateral ventricle of P7 rats to track CSF circulation. 10 minutes post-1.9-nm gold nanoparticle and Red Dextran Tetramethylrhodamine injection and 4 hours post-15-nm gold nanoparticle injection, animals were sacrificed and brains harvested for histologic analysis to identify CSF tracer localization in the cranial and spine meninges and choroid plexus. Spinal dura and leptomeninges (arachnoid and pia) wholemounts were also performed.
RESULTS
There was significantly less CSF tracer distribution in the dura compared to the arachnoid and pia maters in neonatal rodents. Both small and large CSF tracers were transported intracranially to the arachnoid and pia mater of the perimesencephalic cisterns and tela choroidea, but not the dura mater of the falx cerebri. CSF tracers followed a similar distribution pattern in the spinal meninges. In the choroid plexus, there was large CSF tracer distribution in the apical surface of epithelial cells, and small CSF tracer along the basolateral surface. There were no significant differences in tracer intensity in the intracranial meninges of control vs. intraventricular hemorrhage-posthemorrhagic hydrocephalus (PHH) rodents, indicating preserved meningeal transport in the setting of PHH.
CONCLUSIONS
Differential CSF tracer handling by the leptomeninges suggests that there are distinct roles for CSF handling between the arachnoid-pia and dura maters in the developing brain. Similarly, differences in apical vs. luminal choroid plexus CSF handling may provide insight into particle-size dependent CSF transport at the CSF-choroid plexus border.
PubMed: 37645776
DOI: 10.1101/2023.08.10.552826 -
Seminars in Ultrasound, CT, and MR Oct 2023The spinal cord comprises the part of the central nervous system located within the vertebral canal, extending from the foramen magnum to approximately the second lumbar... (Review)
Review
The spinal cord comprises the part of the central nervous system located within the vertebral canal, extending from the foramen magnum to approximately the second lumbar vertebra. The spinal cord is covered by 3 meninges: dura mater, arachnoid mater, and pia mater (arranged from the outermost layer inward). A cross-section of the spinal cord reveals gray and white matter. Ascending and descending pathways have defined locations in the matter of the spinal cord. This article aims to review the spinal cord anatomy and demonstrate the imaging aspects, which are essential for the interpretation and understanding of spinal cord injuries.
Topics: Humans; Meninges; Dura Mater; Spinal Cord; Arachnoid; Pia Mater
PubMed: 37555687
DOI: 10.1053/j.sult.2023.03.011 -
International Journal of Surgery Case... Aug 2023Spinal tumors constitute 15 % of all tumors in the central nervous system. Pain is often the initial symptom, which can be localized, nocturnal, or radiated to the arms...
INTRODUCTION
Spinal tumors constitute 15 % of all tumors in the central nervous system. Pain is often the initial symptom, which can be localized, nocturnal, or radiated to the arms and/or limbs. We report a rare case with a subpial lipoma in the cervicothoracic spine and review the current literature.
CASE PRESENTATION
A 22-year-old female presented with the chief complaint of tetraparesis for three months before admission. Magnetic resonance imaging revealed an intradural tumor on the fifth cervical to fourth thoracic vertebrae. She underwent a laminectomy to remove the tumor completely. Histopathological examination revealed a proliferation of mature fat cells amongst fibrous connective tissue. Surrounding nerve fibers and erythrocyte-filled blood vessels were also found, suggesting a subpial fibrolipoma. Postoperatively, there was an improvement in muscle strength six weeks after surgery. Motoric strength was grade 5 for the upper extremities and grade 4 for the lower extremities.
DISCUSSION
In this patient, cervicothoracic laminectomy and tumor removal were performed without instrumentation. Total tumor resection is the primary goal when removing a pathological lesion. However, this depends on the lesion's adhesion to the surrounding tissue. Therefore, partial tumor resection may be possible, given the neurological complications that can occur.
CONCLUSION
Because subpial lipomas are rare, their treatment is highly specialized. An assessment of the patient's physical condition and imaging assessments can provide information about potential treatment strategies and outcomes.
PubMed: 37544094
DOI: 10.1016/j.ijscr.2023.108616