Intracranial Dura Mater Research Articles

A case of idiopathic hypertrophic pachymeningitis presented with seizures

Idiopathic hypertrophic pachymeningitis (IHP) is a rare disease involving localized inflammatory thickening of the intracranial or spinal dura mater without an identified cause. Seizure is a very unusual presentation of IHP. We present a 58-year-old-female patient with seizures caused by IHP. This case indicates that although IHP is rare, it has the potential to cause seizures.

Histomorphometry of mast cells in the convexity of human intracranial dura mater.

Mast cells, known as pro-inflammatory effector cells, are immunocytes present in the meninges and may be involved in the pathophysiology of migraine. This study aims to evaluate the histomorphometric parameters of mast cells located in the convexity of the human intracranial dura mater. For this, samples of intracranial dura mater from eight human fresh cadavers were collected between 8- and 24-h post-mortem. The whole samples were fixed and, subsequently, two fragments of 1.5cm² each were cut from four different areas of the dura mater convexity, containing a segment of the middle meningeal artery, totaling 64 fragments. After histological processing, the fragments were submitted to microtomy (5 and 10µm), stained with toluidine blue (0.1%), or immunohistochemically labeled for tryptase, and analyzed using optical microscopy. The following histomorphometric parameters were evaluated: distance from mast cells to vessels, the density of mast cells, and percentage of mast cells with degranulation. Histomorphometric analyzes showed a higher density of mast cells in the vicinity of blood vessels (arterial and venous), with distances around 0-150µm. A greater number of mast cells was detected near venous vessels in the periosteal layer (17.0±10.1cells/mm²) than in the meningeal layer (14.1±7.0cells/mm²) (p<0.05). Mast cells from the region close to the superior sagittal sinus were found in greater quantity close to the venous vessels (16.7±10.1cells/mm²) than to the arterial vessels (11.2±7.5cells/mm²) (p<0.05). In short, in the convexity of the human intracranial dura mater, mast cells are located close to blood vessels, with a greater number of cells next to the venous vessels of the periosteal layer and in the proximal region of the superior sagittal sinus.

Histomorphometric analysis of mast cells in different regions of human intracranial dura mater

Objective: To analyze mast cell histomorphometry in three different regions of the human intracranial dura mater. Method: Three specimens of dura mater were collected after approval by the Ethics Committee (CAAE No. 57692216.5.0000.5208). Each dura mater was obtained from human cadavers between 7 and 24 hours after death. After collection, the samples were fixed, cut into two fragments and longitudinally placed in the following way: external (periosteum) and internal (meningeal) sides. The fragments (1.5 cm2) were taken from three different regions: proximity of the right middle meningeal artery, the proximity of the left middle meningeal artery and superior sagittal sinus. These fragments were submitted to microtomy (10 μm), stained with 0.1% toluidineblue and analyzed by optical microscopy. The histomorphometric parameters adopted were: the distance from the mast cells to the vessels, the number and if the mast cells were degranulated. Five fields from each case were analyzed. For this analysis, the Image J 1.52a 2019 software was used. Results: A higher number of mast cells was observed in the periosteal layer when compared withthe meningeal layer (p=0.026). When the distribution of the mast cells was evaluated, we observed that the cells were localized in the proximity of the middle meningeal artery (p&lt;0.05). Conclusion: In human dura mater, the mast cells are localized in the proximity of dural arteries.

Editors' note: Lymphoplasmacyte-rich meningioma involving the whole intracranial dura mater

In the article “Lymphoplasmacyte-rich meningioma involving the whole intracranial dura mater,” Drs. Yang et al. reported a case of a 47-year-old woman with a lesion involving the intracranial dura mater and right trigone of the lateral ventricle, with dense lymphoplasmacytic infiltration on pathology, diagnosed as a rare type of meningioma. Drs. Fukuhara and Makifuchi present a similar case with dense lymphoplasmacytic infiltration that was diagnosed as immunoglobulin G4 (IgG4) pachymeningitis following positive IgG4 immunohistochemical staining. They raise the issue that such inflammatory lesions may be mislabeled as meningiomas with important treatment implications. In response, the authors report that they unsuccessfully tried steroid therapy for their patient. Although immunostainings did demonstrate IgG4 positivity (15 per high-powered field), they contend that this fell short of thresholds for diagnosing IgG4-related disease and that diffuse epithelial membrane antigen expression was supportive of the meningioma diagnosis. In the article “Lymphoplasmacyte-rich meningioma involving the whole intracranial dura mater,” Drs. Yang et al. reported a case of a 47-year-old woman with a lesion involving the intracranial dura mater and right trigone of the lateral ventricle, with dense lymphoplasmacytic infiltration on pathology, diagnosed as a rare type of meningioma. Drs. Fukuhara and Makifuchi present a similar case with dense lymphoplasmacytic infiltration that was diagnosed as immunoglobulin G4 (IgG4) pachymeningitis following positive IgG4 immunohistochemical staining.

Author response: Lymphoplasmacyte-rich meningioma involving the whole intracranial dura mater

After reading Drs. Fukuhara and Makifuchi's comment on our NeuroImage,1 and more related literature,2–4 we agree that lymphoplasmacyte-rich meningioma mimics the whole intracranial pachymeningitis. However, we disagree with the viewpoint that lymphoplasmacyte-rich meningioma mimicking pachymeningitis is due to immunoglobulin G4 (IgG4)–related disease. The patient died during our last follow-up. The total survival time of our patient after the biopsy was about 11 months. In fact, we gave the patient steroid therapy when repeated MRI showed no progression 3 months after biopsy, which was inspired by our previous experience with the treatment of Rosai-Dorfman disease,5 but it was ineffective. Although no detailed serologic evaluations of immunoglobulin levels were performed, immunostainings for IgG4 for plasma cell counts demonstrated an IgG4 of 15 per high-powered field, which fell short of the diagnosis of IgG4-related disease.3 In addition, diffuse membranous epithelial membrane antigen expression highlighted the diagnosis of lymphoplasmacyte-rich meningioma.

Reader response: Lymphoplasmacyte-rich meningioma involving the whole intracranial dura mater.

We read the article by Yang et al.1 that reported lymphoplasmacyte-rich meningioma mimicking the whole intracranial pachymeningitis. We reported immunoglobulin G4 (IgG4) pachymeningitis in a 43-year-old woman who had a history of lymphoplasmacyte-rich meningioma resection in the right middle cranial fossa at age 17, a right orbital granuloma at age 29, and a pulmonary granuloma at age 31.2 She then developed left hearing loss and a hypertrophic dura in the posterior fossa at age 35. Six years later, her MRI showed a left frontal meningioma. The biopsied sample showed dense lymphoplasmatic infiltration and IgG4 was stained immunohistochemically. Recently, pachymeningitis was found to relate to IgG43; so the previously resected samples (meningioma, orbital granuloma, pulmonary granuloma) were restudied and showed positive IgG4 staining. Therefore, our case was a definite IgG4-related pachymeningitis and neurologic symptoms were again improved by steroid therapy. Idiopathic hypertrophic pachymeningitis and lymphoplasmacyte-rich meningioma can be confused on both imaging and histopathologic grounds.4 Lymphoplasmacyte-rich meningioma was occasionally reported to spontaneously regress. Its origin, whether neoplastic or inflammatory, is controversial. The case reported by Yang et al. might be IgG4-related; therefore, steroid therapy might be worth a try.

Análise histomorfométrica de mastócitos em diferentes regiões da dura-máter intracraniana humana

Objective: To analyze mast cell histomorphometry in three different regions of the human intracranial dura mater. Method: Three specimens of dura mater were collected after approval by the Ethics Committee (CAAE No. 57692216.5.0000.5208). Each dura mater was obtained from human cadavers between 7 and 24 hours after death. After collection, the samples were fixed, cut into two fragments and longitudinally placed in the following way: external (periosteum) and internal (meningeal) sides. The fragments (1.5 cm2) were taken from three different regions: proximity of the right middle meningeal artery, the proximity of the left middle meningeal artery and superior sagittal sinus. These fragments were submitted to microtomy (10 μm), stained with 0.1% toluidineblue and analyzed by optical microscopy. The histomorphometric parameters adopted were: the distance from the mast cells to the vessels, the number and if the mast cells were degranulated. Five fields from each case were analyzed. For this analysis, the Image J 1.52a 2019 software was used. Results: A higher number of mast cells was observed in the periosteal layer when compared withthe meningeal layer (p=0.026). When the distribution of the mast cells was evaluated, we observed that the cells were localized in the proximity of the middle meningeal artery (p<0.05). Conclusion: In human dura mater, the mast cells are localized in the proximity of dural arteries.

Idiopathic Hypertrophic Pachymeningitis in the Craniocervical Junction.

Idiopathic hypertrophic pachymeningitis (IHP) is a rare disease, and it is characterized by chronic progressive inflammatory fibrosis and thickening of the dura mater with resultant compression of the spinal cord or neural structure without any identifiable cause. It can occur in the intracranial or spinal dura mater alone or as a craniospinal form. The spinal form is rarer than the cranial form and the craniospinal form is extremely rare. We report a rare case of IHP in the craniocervical junction involving both the cranial and spinal dura mater and discuss the diagnosis and management of the disease.

IgG4-related intracranial hypertrophic pachymeningitis with skull hyperostosis: a case report

BackgroundImmunoglobulin G4 (IgG4)-related disease is a systemic syndrome, characterized by sclerosing lesions and usually associated with a raised serum IgG4 level; the pancreas, salivary glands, and lacrimal glands are typically affected. Recently, it has been suggested that IgG4-related sclerosing disease represents a subset of cases previously diagnosed as idiopathic hypertrophic pachymeningitis. This rare inflammatory disorder causes localized or diffused thickening of intracranial dura mater. Headache, cranial nerve palsy, and ataxia are the most common clinical manifestations.Herein, we report the clinical and histopathological features of a rare case of IgG4-related intracranial hypertrophic pachymeningitis involving cranial hyperostosis.Case presentationA 52-year-old man presented with refractory generalized tonic-clonic seizure. Magnetic resonance imaging revealed thickening of the meninges with enhancement near the superior sagittal sinus; skull bone defect was also noted. Extensive excision of affected skull bone and dura was performed, providing the diagnosis of IgG4-related pachymeningitis. After the surgery, the patient’s seizure stopped and he was smoothly tapered off antiepileptic medication.ConclusionTo our knowledge, this is the first reported case of IgG4-related pachymeningitis with concomitant skull hyperostosis.

Second cranio-facial malignancies in hereditary retinoblastoma survivors previously treated with radiation therapy: Clinic and radiologic characteristics and survival outcomes

IntroductionHereditary retinoblastoma survivors have an increased risk for cranio-facial second primary tumours (SPT), especially after treatment with external beam radiotherapy (EBRT). This multicentre study evaluates the clinical and imaging characteristics and outcomes of cranio-facial SPTs in irradiated retinoblastoma survivors. Patients and MethodsClinical and radiological data of 42 hereditary retinoblastoma patients with 44 second and third malignancies were reviewed. Radiological data included anatomic location and computed tomography (CT) and magnetic resonance (MR) characteristics. Cox regression and likelihood ratio chi-square test were used to evaluate differences in patients’ survival rates. ResultsCranio-facial SPTs were diagnosed at a median age of 13years. Histological types included osteosarcomas (43%), rhabdomyosarcomas (20%) (57% embryonal, 43% alveolar) and a variety of other types of SPT (37%). Predilection sites were: temporal fossa (39%), ethmoid sinus (23%), orbit (18%), maxillary sinus (16%) and intracranial dura mater (4%). Most of the osteosarcomas (78%) and rhabdomyosarcomas (80%) occurred in patients treated with EBRT in the first year-of-life. Treatment of SPTs with a microscopically complete surgical resection led to a significantly better 5-year overall survival (OS) (P=0.017) and event-free survival (EFS) (P=0.012) compared to patients treated without surgery or incomplete resection (OS: 83% versus 52%; EFS: 80% versus 47%). ConclusionsOsteosarcomas and rhabdomyosarcomas are the most common cranio-facial SPTs in irradiated hereditary retinoblastoma survivors, which develop in specific locations and occur predominantly in patients irradiated in their first year-of-life. Microscopically complete surgical resection of SPTs is a major prognostic factor, suggesting the potential benefit of early detection by imaging.

A Case of Hypertrophic Pachymeningitis with Elevated Serum IgG4

Hypertrophic pachymeningitis is a rare disorder in which intracranial dura mater thickens focally or diffusely. To our knowledge, there are few reports of Immunoglobulin G4 (IgG4)-related hypertrophic pachymeningitis. Here, we report the case of such a patient. A 68-year-old woman was referred to our hospital complaining of visual disturbance in her left eye that had persisted for several weeks. There was a history of tuberculosis in her childhood. Brain magnetic resonance imaging showed dural thickening at the bilateral skull base and near the left orbital apex. Visual acuity in her left eye developed marked deterioration. The patient was treated with steroids combined with antituberculosis agents. Following steroid pulse therapy, her symptoms showed rapid amelioration and her visual acuity improved without reactivation of the tuberculosis. Thus, steroid combined with antituberculosis agents is a potential beneficial therapeutic option for patients with IgG4-related disease and tuberculosis.

The Late Recurrence of Ganglioneuroma 21 Years After Initial Presentation with Neuroblastoma

A 3-year-old boy presented with tumors in the adrenal gland and the right orbit, and was diagnosed with neuroblastoma. After chemotherapy, the tumors were resected and the pathological diagnoses of ganglioneuroblastoma in the adrenal gland and ganglioneuroma in the orbit were made. The tumor relapsed at the intracranial dura mater 21 years after the initial diagnosis, and was diagnosed as ganglioneuroma from a biopsied sample. This case is very unique in that ganglioneuroma matured from ganglioneuroblastoma or neuroblastoma had the late recurrence with 21 years of tumor dormancy.

The cranial dura mater: a review of its history, embryology, and anatomy

The dura mater is important to the clinician as a barrier to the internal environment of the brain, and surgically, its anatomy should be well known to the neurosurgeon and clinician who interpret imaging. The medical literature was reviewed in regard to the morphology and embryology of specifically, the intracranial dura mater. A historic review of this meningeal layer is also provided. Knowledge of the cranial dura mater has a rich history. The embryology is complex, and the surgical anatomy of this layer and its specializations are important to the neurosurgeon.

Dural metastases as a presentation of a Brenner tumor

We present a 56-year-old woman who came to our institution with a 6-month history of intracranial hypertension. Imaging studies showed diffuse dural enhancement, multiple lytic bone lesions and a tumor in the left ovary. A meningeal biopsy was performed; however, during this procedure the patient developed profuse dural hemorrhage and middle cerebral artery territory infarction and died a few hours later. The autopsy revealed a disseminated Brenner tumor that was infiltrating the intracranial dura mater. At this site neovascularization, vascular infiltration by malignant cells and a desmoplastic reaction were all observed, perhaps rendering the patient more susceptible to a dural hemorrhage during the biopsy. To our knowledge, this is the first report of a Brenner tumor presenting as dural metastases.

Label-free and highly sensitive optical imaging of detailed microcirculation within meninges and cortex in mice with the cranium left intact

We demonstrate for the first time that the detailed blood flow distribution within intracranial dura mater and cortex can be visualized by an ultrahigh sensitive optical microangiography (UHS-OMAG). The study uses an UHS-OMAG system operating at 1310 nm with an imaging speed at 150 frames per second that requires approximately 10 s to complete one 3-D scan of approximately 2.5 x 2.5 mm(2). The system is sensitive to blood flow with a velocity ranging from approximately 4 microms to approximately 23 mms. We show superior performance of UHS-OMAG in providing functional images of capillary level microcirculation within meninges in mice with the cranium left intact, the results of which correlate well with the standard dural histopathology.

Pleomorphic liposarcoma originating from intracranial dura mater

Liposarcomas are the most common soft tissue sarcoma found in adults; however, disease involving or spreading to the head and neck is extremely rare. To our knowledge, we present the first case of primary pleomorphic liposarcoma originating intracranially. A 56-year-old man presented with new weakness and imaging findings confirming a right frontal mass. After resection, histological analysis confirmed the diagnosis of pleomorphic liposarcoma. The patient underwent radiation treatment and surveillance imaging, which revealed no other areas of disease. Results reported previously in the literature indicate that pleomorphic liposarcoma is very aggressive in nature. The authors review the few cases of primary or metastatic pleomorphic liposarcoma that have been reported involving the head.

Localization of COX-1 and COX-2 in the intracranial dura mater of the rat

Primary headaches such as migraine can be aborted by systemic administration of non-steroidal anti-inflammatory drugs (NSAIDs), potentially through the non-selective inhibition of cyclooxygenase (COX) activity in the intracranial meninges. In this study we have used single and double labeling immunohistochemistry to examine the distribution of the COX-1 and COX-2 isoforms in the intracranial dura mater of the rat and identify cell types that express them. COX-1 immunoreactivity was found in medium and small dural blood vessels and was co-expressed with the endothelial cell markers vimentin and the endothelial isoform of nitric oxide synthase (ecNOS). COX-1 was also found to be present in most dural mast cells. COX-2 was mainly expressed in ED2-positive resident dural macrophages. Constitutive COX-2 expression was also found in some axonal profiles, many of which were co-labeled with the nociceptor peptide marker CGRP. The findings suggest that NSAIDs may abort headache, at least in part, by inhibiting either neuronal or non-neuronal COX activity in the dura mater.

Cavernous hemangioma extending to extracranial, intracranial, and orbital regions

Extraaxial cavernous hemangiomas are rare intracranial lesions that can be located in different cranial compartments. Extension across different tissue planes such as the subcutaneous tissue, skull, orbital cavity, intracranial dura mater, and extracranial trigeminal divisions within the same patient has not been previously reported. This 32-year-old woman suffered left exophthalmos, left sixth nerve palsy, and trigeminal neuropathy. Magnetic resonance imaging studies revealed an extensive multicompartmental lesion, with enhancement following Gd administration. A left orbitopterional approach allowed removal of several cavernomatous lesions located in the orbit, frontotemporal dura, and lateral wall of the cavernous sinus. A histologically based diagnosis of extraaxial cavernous hemangioma was made. In the postoperative period the patient experienced a regression of her symptoms. The authors report on a case of cavernous hemangioma with a unique extension to different intracranial/extracranial compartments. Although radical removal of the lesion was not feasible, partial excision allowed for satisfactory clinical control of the patient's symptoms.

Alternative EWS‐FLI1 fusion gene and MIC2 expression in peripheral and central primitive neuroectodermal tumors

Primitive neuroectodermal tumors (PNET) occur either in the central nervous system (CNS; central PNET, cPNET) or in the peripheral sites (peripheral PNET, pPNET). Recent molecular approaches have been defining a new concept of PNET, that is, the pPNET including Ewing's sarcoma (ES) which expresses MIC2 glycoprotein and shows the specific chimeric gene of EWS‐FLI1. The expression of MIC2 and the genetic rearrangement of EWS‐FLI1 are considered to be highly specific to the pPNET/ES. This study examined the expression of MIC2 and EWS‐FLI1 gene by means of immunohistochemistry and reverse transcriptase–polymerase chain reaction (RT‐PCR) on various small round cell tumors originating in the CNS or non‐CNS organs. All peripheral PNET tested expressed MIC2 and were positive for EWS‐FLI1 (11/11). In contrast, all cPNET and other blastic CNS tumors were negative for MIC2: medulloblastoma (0/3), cerebral PNET (0/2), spinal PNET (0/2), glioblastoma (0/2), retinoblastoma (0/3), and pineoblastoma (0/2). These MIC2‐negative tumors were also negative for the chimeric gene product of EWS‐FLI1. Interestingly, one PNET originating in the intracranial dura mater was positive for both MIC2 and EWS‐FLI1 fusion gene. The results indicate that cPNET lacks any genetic or protein markers, except for a meningeal PNET which falls into the same phenotypic spectrum of pPNET.

Alternative EWS-FLI1 fusion gene and MIC2 expression in peripheral and central primitive neuroectodermal tumors.

Primitive neuroectodermal tumors (PNET) occur either in the central nervous system (CNS; central PNET, cPNET) or in the peripheral sites (peripheral PNET, pPNET). Recent molecular approaches have been defining a new concept of PNET, that is, the pPNET including Ewing's sarcoma (ES) which expresses MIC2 glycoprotein and shows the specific chimeric gene of EWS-FLI1. The expression of MIC2 and the genetic rearrangement of EWS-FLI1 are considered to be highly specific to the pPNET/ES. This study examined the expression of MIC2 and EWS-FLI1 gene by means of immunohistochemistry and reverse transcriptase-polymerase chain reaction (RT-PCR) on various small round cell tumors originating in the CNS or non-CNS organs. All peripheral PNET tested expressed MIC2 and were positive for EWS-FLI1 (11/11). In contrast, all cPNET and other blastic CNS tumors were negative for MIC2: medulloblastoma (0/3), cerebral PNET (0/2), spinal PNET (0/2), glioblastoma (0/2), retinoblastoma (0/3), and pineoblastoma (0/2). These MIC2-negative tumors were also negative for the chimeric gene product of EWS-FLI1. Interestingly, one PNET originating in the intracranial dura mater was positive for both MIC2 and EWS-FLI1 fusion gene. The results indicate that cPNET lacks any genetic or protein markers, except for a meningeal PNET which falls into the same phenotypic spectrum of pPNET.