Clinical, Radiological, and Etiological Aspects of Pachymeningitis: A Study of 24 Cases.

Introduction and importance Hypertrophic pachymeningitis (HP) is an uncommon disorder with varied etiological origins and heterogeneous clinical presentation. Establishing the etiological diagnosis poses a challenge, but prompt identification provides a treatment window, potentially leading to a reversal of symptoms. MRI is the reference examination, allowing not only the early diagnosis of pachymeningitis but also the assessment of its extent and importance, detection of possible complications, and suggestion of etiology. Case presentation We conducted a retrospective study involving 24 patients recruited over 5 years for who brain imaging had revealed the presence of pachymeningitis. The average age of the patients was 40 years, with a male-to-female ratio of 0.6. Clinical discussion Headache was present in 54.17% of patients. All the patients underwent MRI examinations utilizing different sequences, with subsequent Gadolinium injection showing localized and asymmetrical meningeal thickening in 13 cases, and diffuse in the rest. The cerebrospinal fluid study unveiled an inflammatory fluid characterized by a lymphocytic predominance and hyperproteinorrhea, noted in 50% of the patients. The histopathological analysis of a stereotactic biopsy conducted on an individual patient revealed non-diagnostic results. The etiological investigation was dominated by tuberculosis, which was detected in 33.3% of cases. Idiopathic origin was identified in 16.7% of patients. Conclusion Meningeal thickening is rare, and the multitude of potential causes makes the etiological investigation challenging unless they fall within the scope of secondary meningeal disorders; otherwise, a dural biopsy becomes necessary, and the prompt initiation of treatment, along with determining the etiology influences the prognosis.

Meningioma originating from the superior petrosal vein without dural attachment: A case report.

BACKGROUND: Meningioma in the cerebellopontine angle (CPA) without dural attachment is extremely rare. We report a unique case of meningioma derived from the superior petrosal vein without dural attachment. CASE SUMMARY: A 44-year-old right-handed woman presented with a two-month history of headache and tinnitus. Brain magnetic resonance imaging showed a well-defined contrast-enhancing lesion in the right CPA without a dural tail sign. Tumor resection was performed using a right retro sigmoid approach. A dural attachment was not seen at the tentorium or posterior surface of the petrous pyramid. The tumor was firmly adherent to the superior petrosal vein. The origin site was cauterized and resected with the preservation of the superior petrosal vein. A diagnosis of meningothelial meningioma was made. The patient's headache and tinnitus gradually disappeared, and a recurrence was not observed five years after the surgery. CONCLUSION: The rare occurrence of meningioma without dural attachment makes it difficult to determine dural attachment before surgery. The absence of dural attachment makes it easy to completely resect such tumors. Vessels related to tumors should be removed carefully, considering the possible presence of tumor stem cells in the microvessels.

High incidence of dural tears with 3-column osteotomies: a systematic review of adult spinal deformity surgery literature for the past decade.

PURPOSE: Dural tear (DT) is a well-known complication of spinal surgery. We aimed to systematically review the literature from the past decade and determine the incidence and risk factors for DT in the adult spinal deformity (ASD) population to improve both the surgical strategy and counseling of patients undergoing ASD correction. METHODS: A systematic review from 2013 to 2023 utilizing PRISMA guidelines was performed. The MEDLINE database was used to collect primary English language articles. The inclusion criterion for patients was degenerative ASD. Pediatric studies, animal studies, review articles, case reports, studies investigating minimally invasive surgery (MIS), studies lacking data on DT incidence, and articles pertaining to infectious, metastatic or neoplastic, traumatic, or posttraumatic etiologies of ASD were excluded. RESULTS: Our results demonstrate that the incidence of DT in ASD surgery ranges from 2.0% to 35.7%, which is a much broader range than the reported incidence for non deformity surgery. Moreover, the average rate of DT during ASD surgery stratified by surgical technique was greater for osteotomy overall (19.5% +/- 7.9%), especially for 3-column osteotomy (3CO), and lower for interbody fusion (14.3% +/- 9.9%). Risk factors for DT in the ASD surgery cohort included older age, revision surgery, chronic severe compression, higher-grade osteotomy, complexity of surgery, rheumatoid arthritis (RA), and higher Anesthesiology Society of America (ASA) grade. CONCLUSION: To our knowledge, this is the first systematic review discussing the incidence of and risk factors for DT in the ASD population. We found that the risk factors for DT in ASD patients were older age, revision surgery, chronic severe compression, a greater degree of osteotomy, complexity of surgery, RA, and a higher ASA grade. These findings will help guide spine surgeons in patient counseling as well as surgical planning.

The Impact of VEGF-C-Induced Dural Lymphatic Vessel Growth on Ischemic Stroke Pathology.

Timely relief of edema and clearance of waste products, as well as promotion of anti-inflammatory immune responses, reduce ischemic stroke pathology, and attenuate harmful long-term effects post-stroke. The discovery of an extensive and functional lymphatic vessel system in the outermost meningeal layer, dura mater, has opened up new possibilities to facilitate post-stroke recovery by inducing dural lymphatic vessel (dLV) growth via a single injection of a vector encoding vascular endothelial growth factor C (VEGF-C). In the present study, we aimed to improve post-stroke outcomes by inducing dLV growth in mice. We injected mice with a single intracerebroventricular dose of adeno-associated viral particles encoding VEGF-C before subjecting them to transient middle cerebral artery occlusion (tMCAo). Behavioral testing, Gadolinium (Gd) contrast agent-enhanced magnetic resonance imaging (MRI), and immunohistochemical analysis were performed to define the impact of VEGF-C on the post-stroke outcome. VEGF-C improved stroke-induced behavioral deficits, such as gait disturbances and neurological deficits, ameliorated post-stroke inflammation, and enhanced an alternative glial immune response. Importantly, VEGF-C treatment increased the drainage of brain interstitial fluid (ISF) and cerebrospinal fluid (CSF), as shown by Gd-enhanced MRI. These outcomes were closely associated with an increase in the growth of dLVs around the region where we observed increased vefgc mRNA expression within the brain, including the olfactory bulb, cortex, and cerebellum. Strikingly, VEGF-C-treated ischemic mice exhibited a faster and stronger Gd-signal accumulation in ischemic core area and an enhanced fluid outflow via the cribriform plate. In conclusion, the VEGF-C-induced dLV growth improved the overall outcome post-stroke, indicating that VEGF-C has potential to be included in the treatment strategies of post-ischemic stroke. However, to maximize the therapeutic potential of VEGF-C treatment, further studies on the impact of an enhanced dural lymphatic system at clinically relevant time points are essential.

[Clinical analysis of resection and dura skull base reconstruction of cranionasal communication tumor in 31 cases].

Objective:To explore the methods of resection, dura and skull base repair and reconstruction of cranionasal communication tumor. Methods:Data of 31 patients with cranionasal communication tumor who underwent dura and skull base reconstruction after tumor resection from 2018 to 2022 were collected. Follow-up lasted for 3 to 41 months. Results:A total of 31 patients were enrolled, including 20 males and 11 females. The ages ranged from 19 to 74 years, with a median age of 57 years old. There were 17 benign lesions（one case of hemangioma, one case of Rathke cyst, one case of squamous papilloma, one case of craniopharyngioma, two cases of meningocele, two cases of varus papilloma, two cases of meningioma of grade Ⅰ, three cases of schwannoma, four cases of pituitary tumor） and 14 malignant lesions（one case of osteosarcoma, one case of poorly differentiated carcinoma, two cases of varus papilloma malignancy, two cases of olfactory neuroblastoma, two cases of adenocarcinoma, two cases of adenoid cystic carcinoma, four cases of squamous cell carcinoma） . Sixteen cases underwent nasal endoscopy combined with craniofacial incision and 15 cases underwent nasal endoscopy surgery alone. Complete resection of the mass and dura and skull base reconstruction were performed in all 31 patients, and free graft repair was performed in 8 cases（fascia lata in 5 cases and nasal mucosa in 3 cases）. Twenty-three cases were repaired with pedicled flaps（septal mucosal flap alone in 11 cases, septal mucosal flap combined with free graft in 6 cases, and cap aponeurosis combined with free graft in 6 cases）. Eight out of 31 patients underwent skull base bone repair. Postoperative cerebral hemorrhage occurred in 1 case, cerebrospinal fluid leakage in 1 case, intracranial infection in 2 cases. All patients were successfully treated without severe sequelae. Cerebrospinal fluid leakage and intracranial infection occurred in one patient after radiotherapy, who recovered after conservative treatment. All 17 patients with benign lesions survived. Thirteen out of 14 patients with malignant lesions received radiotherapy after surgery, nine survived without recurrence, five cases recurred, of which 2 survived with tumor, one underwent reoperation and 2 died. Conclusion:Cranionasal communication tumors are high-risk diseases of anterior and middle skull base, and various surgical repair methods could be selected after complete resection of the tumor. Successful reconstruction and multidisciplinary cooperation are crucial for treatment outcome.

Classical monocyte ontogeny dictates their functions and fates as tissue macrophages.

Classical monocytes (CMs) are ephemeral myeloid immune cells that circulate in the blood. Emerging evidence suggests that CMs can have distinct ontogeny and originate from either granulocyte-monocyte- or monocyte-dendritic-cell progenitors (GMPs or MDPs). Here, we report surface markers that allowed segregation of murine GMP- and MDP-derived CMs, i.e., GMP-Mo and MDP-Mo, as well as their functional characterization, including fate definition following adoptive cell transfer. GMP-Mo and MDP-Mo yielded an equal increase in homeostatic CM progeny, such as blood-resident non-classical monocytes and gut macrophages; however, these cells differentially seeded various other selected tissues, including the dura mater and lung. Specifically, GMP-Mo and MDP-Mo differentiated into distinct interstitial lung macrophages, linking CM dichotomy to previously reported pulmonary macrophage heterogeneity. Collectively, we provide evidence for the existence of two functionally distinct CM subsets in the mouse that differentially contribute to peripheral tissue macrophage populations in homeostasis and following challenge.

"The novel dura substitute: a revolutionary advancement in neurosurgery".

This Article provides a concise summary of the comprehensive exploration into the dura mater, dural tears, and the groundbreaking medical device, ArtiFascia® Dura Substitute. The neuroanatomy of the dura mater is elucidated, emphasizing its resilience and susceptibility to tears during spinal surgery. Dural repair methods are scrutinized, with research findings revealing the efficacy of primary closure with or without a patch.The introduction of ArtiFascia®, a nanofiber-based resorbable dural repair graft, represents a pivotal moment in neurosurgery. Obtaining 510(k) clearance from the FDA, ArtiFascia® demonstrates exceptional biological benefits, including enhanced cellular adhesion and tissue regeneration. The device's safety is affirmed through chemical analysis and toxicological risk assessment.The NEOART study, a randomized clinical trial involving 85 subjects across prominent European medical centers, validates ArtiFascia®'s superiority over existing dural substitutes. Noteworthy findings include exceptional graft strength, durability, and its ability to withstand physiological pressures.In conclusion, ArtiFascia® marks a revolutionary era in neurosurgery, promising safer and more effective solutions. This innovative device has the potential to elevate standards of care, offering both patients and surgeons an improved experience in navigating the complexities of neurosurgical procedures. The abstract encapsulates the key elements of the research, emphasizing the transformative impact of ArtiFascia® in the field.

Incidental dural tears during pediatric posterior spinal fusions.

PURPOSE: To characterize the frequency of incidental dural tears in pediatric spine surgery, their treatment, complications, and results of long-term follow-up. METHODS: A retrospective review of all pediatric patients who underwent a posterior spinal fusion (PSF) between 2004-2019 at a tertiary children's hospital was conducted. Electronic medical records were reviewed for patient demographics, intra-operative data, presence of an incidental dural tear, repair method, and patient outcomes. RESULTS: 3043 PSFs were reviewed, with 99 dural tears identified in 94 patients (3.3% overall incidence). Mean follow-up was 35.7 months (range 0.1-142.5). When the cause of the dural tear was specified, 69% occurred during exposure, 5% during pedicle screw placement, 4% during osteotomy, 2% during removal of implants, and 2% during intra-thecal injection of morphine. The rate of dural tears during primary PSF was significantly lower than during revision PSF procedures (2.6% vs. 6.2%, p < 0.05). 86.9% of dural tears were repaired and/or sealed intraoperatively, while 13.1% had spontaneous resolution. Postoperative headaches developed in 13.1% of patients and resolved at a mean of 7.6 days. There was no difference in the incidence of headaches in patients that were ordered bedrest vs. no bedrest (p > 0.99). Postoperative infections occurred in 9.5% of patients and 24.1% patients were identified to have undergone a revision surgery. CONCLUSIONS: Incidence of intra-operative dural tears in pediatric spine surgery is 3.3%. Although complications associated with the dural tear occur, most resolve over time and there were no long-term sequelae in patients with 2 years of follow up. LEVEL OF EVIDENCE: Level IV.

Cerebral tumor with hemi-dural enhancement as unique presentation of multiple myeloma: A case report.

Introduction: Intracranial multiple myeloma (MM) is a rare manifestation of MM, a malignant plasma cell disorder that primarily affects bone marrow. Dural involvement in MM is even rarer and can manifest as a dural mass. We present a case of MM presenting as an intracranial dural tumor with primary hemi-dural involvement. Research question: This case report aims to investigate the clinical presentation, diagnostic challenges, and treatment approaches for intracranial multiple myeloma, with a focus on the extensive hemi-dural thickening and enhancement seen in this case. Material and methods: A 73-year-old male presented with progressive dysphasia and weakness. MRI revealed a solid left frontal mass with significant mass-effect. Hemi-dural thickening and enhancement was present along with invasion of the skull. The patient underwent surgical resection of the tumor with dural and bone reconstruction. Results: Histopathological examination confirmed MM diagnosis. Chemotherapy was started. Follow-up MRI showed complete tumor resection, but extensive hemi-dural thickening and enhancement persisted. Postoperative radiation therapy was considered. Discussion and conclusion: MM with primary dural involvement is rare and poses diagnostic challenges. Postoperative treatment involves chemotherapy, the role of surgery and radiotherapy is not established. The extensive hemi-dural thickening and enhancement observed in this case require further investigation, and a wait-and-scan policy was recommended instead of radiotherapy.

The cavernous sinus: An anatomic study with clinical implication.

Objective: The management of lesions involving the cavernous sinus remains a formidable challenge. To optimize care for patients with tumors extending into this skull base region a detailed understanding of the surrounding osteology as well as neural and vascular relationships is requisite. This thesis examines the gross anatomy of the region and highlights important surgical implications drawn from these as well as previously published studies. Methods: A review of the historical scientific, anatomic, clinical, and surgical literature extending to the present (1992) relating to the cavernous sinus has been performed and discussed. Additionally, the author has performed and described cadaveric dissections revealing novel details about the macroscopic (dural and neurovascular anatomic relationships) and microscopic structure of the cavernous sinus. A series of cases of cavernous sinus pathologies that were addressed in an interdisciplinary surgical approach at the author's institution is also reported. Results: Included in this report is a comprehensive review of the embryology of the cavernous sinus and its associated neurovascular structures. Cadaveric dissections have also revealed novel details about dural/meningeal compartments of the cavernous sinus as well as well as associated arterial, venous, and neural relationships. Microscopic observations also reveal novel fundamental insights into the components and structure of the cavernous sinus. Clinical examples from 20 patients illustrate the critical importance for clinical application of cavernous sinus anatomic knowledge to the surgical treatment of pathologies in this region. Conclusion: The cavernous sinus is a tripartite venous osteomeningeal compartment intimately neighboring vital structures including the optic tracts, pituitary gland, cranial nerves III, IV, V, V, VI, and the internal carotid artery. Surgical management of cavernous sinus lesions has and continues to evolve with increasing anatomic and clinical study as well as advancements in diagnostic and surgical methodologies. Level of Evidence: NA.

Dural composite hemangioendothelioma: The first intracranial case.

Background: Composite hemangioendothelioma (CHE) is a rare, locally aggressive neoplasm of intermediate malignant potential. It is composed of a mixture of vascular tumors with a predilection for the dermis and subcutis of the extremities. Case Description: In this report, we describe a 41-year-old man who presented with a 2-month history of headache, dizziness, and intermittent seizures. Magnetic resonance imaging showed a hemorrhagic, multilobulated, and dural-based mass with extension into the calvarium. The mass measured 10.3 × 4.8 × 4 cm along the interhemispheric fissure and encased the superior sagittal sinus. Excision was performed, and histopathologic examination revealed a heterogeneous mixture of vascular components consisting of epithelioid hemangioendothelioma, retiform hemangioendothelioma, and hemangioma. This is the first report of a primary intracranial CHE. Conclusion: The spectrum of mesenchymal neoplasms within the cranium expands to encompass CHE.

Neonatal IL-4 Over-Exposure is Accompanied by Macrophage Accumulation in Dura Mater After Instant Anti-inflammatory Cytokine Response in CSF.

Multiple studies have shown that clinical events resulting into neonatal IL-4 over-exposure, such as asthma in early life and food allergy, were associated with brain damage and that the neuroinflammation induced by them might lead to cognitive impairments, anxiety-/depressive-like behaviors. IL-4 is the most major elevated cytokine in periphery when these clinical events occur and peripheral IL-4 level positively correlates with the severity of those events. Our previous studies have verified that neonatal IL-4 over-exposure induced a delayed neuroinflammatory damage in rodents, which might have adverse implications for brain development and cognition. Neuroinflammation in brain parenchyma is often accompanied by changes in CSF cytokines levels. However, whether the cytokines levels in CSF change after neonatal IL-4 over-exposure is unknown. Here, we found a delayed pro-inflammatory cytokines response (higher IL-6, IL-1ß and, TNF levels) in both hippocampus and CSF after an instant anti-inflammatory cytokine response in IL-4 over-exposed rats. Moreover, the pro-inflammatory cytokines response appeared earlier in CSF than in hippocampus. The level of each of the pro-inflammatory cytokines in CSF positively correlated with that in hippocampus at the age of postnatal day 42. More microglia numbers/activation and higher M-CSF level in the hippocampus in IL-4 over-exposed rats were also observed. Furthermore, there were more macrophages with inflammatory activation in dural mater of IL-4 over-exposed rats. In sum, neonatal IL-4 over-exposure in rats induces delayed inflammation in CSF, suggesting CSF examination may serve as a potential method in predicting delayed neuroinflammation in brain following neonatal IL-4 over-exposure.

Low-grade fibromyxoid tumor of the dura: A new entity?

Background: Low-grade fibromyxoid tumors are uncommon in children. Their differentiation from high-grade fibromyxoid tumors, as seen in adults, is imperative to diagnosis. Awareness of the entity and its subsequent behavior may guide management and predict outcomes. Case Description: We describe the case of a previously unreported low-grade fibromyxoid tumor of the cerebellum in an 8-year-old male. Extensive immunohistochemical, next-generation sequencing, and attempted DNA methylation profiling are reported. There has been no recurrence during the 6-year follow-up. Screening excluded multiple myxoid tumors, including low-grade fibromyxoid sarcoma. The findings suggest that, with gross total resection, the lesions may not recur. Conclusion: The case of fibromyxoid tumor with 6-year follow-up and the limited literature of similar tumors are reviewed.

An Incidental Finding of Idiopathic Hypertrophic Pachymeningitis: A Case Report.

In this case report, we discuss and explore the clinical, laboratory, and imaging findings, as well as the treatment options and follow-up measures, in an 83-year-old patient with idiopathic hypertrophic pachymeningitis (IHP), a rare disorder characterized by fibrosing, hypertrophic inflammation that thickens the dura mater. An 83-year-old female with a medical history of hypertension and hyperlipidemia presented with speech arrest and was taken to the emergency department, where she received a stroke code, a CT scan, and an MRI. The MRI results showed a temporal lobe meningioma and a pan-cranial pachymeningitis encasing the entire brain and cerebellum and extending into the upper cervical spine. Multiple unsuccessful attempts at a lumbar puncture were made, so a dural biopsy specimen was obtained, which revealed no malignant process. A cerebral spinal fluid specimen (CSF) from the biopsy showed minimal white blood cells (WBCs) which ruled out infection. Idiopathic hypertrophic pachymeningitis was the given diagnosis based on the apparent MRI findings. The patient was treated in the hospital for four days with IV methylprednisolone and discharged on oral methylprednisolone for four to six weeks.

Characterization of pediatric non-hematopoietic tumor metastases to the central nervous system: A single institution review.

Central nervous system (CNS) metastases represent a small portion of pediatric CNS neoplasms and data surrounding this condition with high morbidity is scarce. Single institutional archival institutional pathology records between 1999 and 2022 were searched for patients over 21 years old and younger with CNS, dura, cranial nerve, CSF, or leptomeningeal metastases; 41 cases were identified. We documented primary tumor types and locations, metastasis locations, types of invasion (direct extension vs distant metastasis), times from imaging or pathologic diagnosis to CNS involvement, and outcomes. Distant metastasis was the most common mechanism of metastasis (n = 32, 78%). Interval times to CNS metastasis varied by both tumor type and primary tumor location. In this cohort, osteosarcoma portended the shortest survival following CNS metastasis. This study highlights the diverse mechanisms and locations of CNS involvement in pediatric CNS metastases and illuminates a need for varied monitoring strategies when considering primary tumor type and anatomic location.

Leukocyte- and platelet-rich fibrin in cranial surgery: a single-blinded, prospective, randomized controlled noninferiority trial.

OBJECTIVE: CSF leakage is a major complication after cranial surgery, and although fibrin sealants are widely used for reinforcing dural closure, concerns exist regarding their safety, efficacy, and cost. Leukocyte- and platelet-rich fibrin (L-PRF), an autologous platelet concentrate, is readily available and inexpensive, making it a cost-effective alternative for commercially available fibrin sealants. This study aimed to demonstrate the noninferiority of L-PRF compared with commercially available fibrin sealants in preventing postoperative CSF leakage in supra- and infratentorial cranial surgery, with secondary outcomes focused on CSF leakage risk factors and adverse events. METHODS: In a single-blinded, prospective, randomized controlled interventional trial conducted at a neurosurgery department of a tertiary care center (UZ Leuven, Belgium), patients undergoing elective cranial neurosurgery were randomly assigned to receive either L-PRF (active treatment) or commercially available fibrin sealants (control) for dural closure in a 1:1 ratio. RESULTS: Among 350 included patients, 328 were analyzed for the primary endpoint (44.5% male, mean age 52.3 ± 15.1 years). Six patients (5 in the control group, 1 in the L-PRF group) presented with CSF leakage requiring any intervention (relative risk [RR] 0.20, one-sided 95% CI -∞ to 1.02, p = 0.11), confirming noninferiority. Of these 6 patients, 1 (in the control group) presented with CSF leakage requiring revision surgery. No risk factors for reconstruction failure in combination with L-PRF were identified. RRs for adverse events such as infection (0.72, 95% CI -∞ to 1.96) and meningitis (0.36, 95% CI -∞ to 1.25) favored L-PRF treatment, although L-PRF treatment showed slightly more bleeding events (1.44, 95% CI -∞ to 4.66). CONCLUSIONS: Dural reinforcement with L-PRF proved noninferior to commercially available fibrin sealants, with no safety issues. Introducing L-PRF to standard clinical practice could result in important cost savings due to accessibility and lower cost. Clinical trial registration no.: NCT03812120 (ClinicalTrials.gov).

Bovine Pericardium Treated with Polyethylene Glycol and Ethanol Versus Pericranium for Duraplasty: A Pilot Study in Supratentorial Neurosurgery.

BACKGROUND: Watertight closure of dura mater after intracranial surgery can avoid cerebrospinal fluid leakage and central nervous system infection and herniation. When primary closure is not possible, the pericranium is the preferential choice. When it is not available, a dural substitute becomes necessary. Bovine pericardium treated with polyethylene glycol and ethanol is herein tested as a dural substitute. METHODS: A pilot study comparing bovine pericardium with pericranium in supratentorial neurosurgery was performed. RESULTS: Twenty patients were initially allocated into a bovine pericardium group (group 1) or a pericranium group (group 2). Three patients from group 1 and 2 from group 2 had a loss of follow-up, being excluded. In the remaining 15 patients, epidemiological analysis demonstrated a male:female ratio of 3:4 and 4:4 for groups 1 and 2. Ages varied from 28 to 68 (Mean = 49.6) in group 1 and 40-80 (Mean = 61.2) in group 2, with a mean difference of 11.68 years (P = 0.09). Two cases of surgical site infection and 1 of hydrocephalus were observed. Although the calculated relative risk for complications was higher in group 1 (Relative Risk = 1.08), Fisher exact test demonstrated no statistically significant difference between groups (P = 1.00). Procedure mean time was 23 minutes and 11 seconds in group 1 versus 27 minutes and 55 seconds in group 2 (P = 0.47). Mean graft area was 13.17 and 6.23 cm2 in groups 1 and 2 (P = 0.02). CONCLUSIONS: Bovine pericardium treated with polyethylene glycol and ethanol was comparable to pericranium as a dural substitute. More studies are encouraged to certify our findings.

Peptidomics insights: neutrophil extracellular traps (NETs) related to the chronic subdural hemorrhage.

Chronic subdural hemorrhage (CSDH) refers to a hematoma with an envelope between the dura mater and the arachnoid membrane and is more common among the elderly. It was reported that the dura mater, which is highly vascularized with capillary beds, precapillary arterioles and postcapillary venules play an important role in the protection of the central nervous system (CNS). Numerous evidences suggests that peptides play an important role in neuroprotection of CNS. However, whether dura mater derived endogenous peptides participate in the pathogenesis of CSDH remains undetermined. In the current study, the peptidomic profiles were performed in human dura of CSDH (three patients) and the relative control group (three non-CSDH samples) by LC-MS (liquid chromatography-mass spectrometry). The results suggested that a total of 569 peptides were differentially expressed in the dura matter of CSDH compared with relative controls, including 217 up-regulated peptides and 352 down-regulated peptides. Gene Ontology (GO) analysis demonstrated that the precursor proteins of those differentially expressed peptides were involved in the various biological processes. Interestingly, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis suggested that NETs participated in the pathogenies of CSDH. Further investigate showed that H3Cit was significantly elevated in the dural and hematoma membranes of patients with CSDH compared to patients without CSDH. Taken together, our results showed the differentially expressed peptides in human dura mater of CSDH and demonstrated that NETs formation in the dural and hematoma membranes might be involved in the pathogenesis of CSDH. It is worth noting that pharmacological inhibition of NETs may have potential therapeutic implications for CSDH.

Nonmeningothelial Dural-Based Lesions: A Histopathological Analysis.

Introduction We report 30 cases of nonmeningothelial dural-based lesions encountered during a 3-year study period. Materials and Methods We retrospectively reviewed pathology records of patients operated for extra-axial, dural-based lesions during the years 2016 to 2018 and included nonmeningothelial lesions as a part of this study. Results Among the 3,243 neurosurgical specimens for histopathologic examination, only 30 (0.93%) were "nonmeningothelial dural-based lesions." Six (20%) patients were in the pediatric age group. Pathologic assessment identified 13 cases of solitary fibrous tumor/hemangiopericytoma (43.3%) and 7 cases of Ewing's sarcoma/primitive neuroectodermal tumor (23.3%). Two cases (6.7%) were of metastasis. Other lesions included a single case each of non-Hodgkin's lymphoma, undifferentiated sarcoma, solitary plasmacytoma, and granulocytic sarcoma. Nonneoplastic lesions included two cases each of Rosai-Dorfman disease and nonspecific inflammatory lesions. Conclusion Nonmeningothelial dural-based lesions being rare, thorough examination of morphological features is a must by the pathologist, to arrive at the accurate diagnosis. Ancillary tests, if required, should be employed in the context of the morphologic picture.