Meningeal sarcoidosis, pseudo-meningioma, and pachymeningitis of the convexity

Neurosarcoidosis resembling multiple meningiomas: A misleading presentation of the disease and diagnostic challenge

Sarcoidosis is characterized by the presence of noncaseating granulomatous inflammation in the affected organs. Neurosarcoidosis denotes the involvement of the nervous system and can be either isolated or coexisting with extraneural systemic inflammation. The diagnosis of isolated neurosarcoidosis may be challenging due to unspecific symptoms and similar appearances with other disease processes. This report presents an uncommon case of intracranial sarcoidosis mimicking multiple meningiomas. Familiarity with the spectrum of magnetic resonance imaging findings in neurosarcoidosis is crucial to prevent interpretive errors which may in turn lead to an inappropriate diagnosis and treatment.

Clinical features of hypertrophic pachymeningitis in a center survey

BACKGROUND

Hypertrophic pachymeningitis (HP) is characterized by cranial and/or spinal thickening of the dura mater with or without associated inflammation. Neuroimaging studies reveal dura mater thickening and focal or diffuse contrast enhancement. It is described in association with trauma, infections, tumors, autoimmune/inflammatory diseases, and cerebrospinal fluid hypotension syndrome, with some cases remaining idiopathic.

METHODS

A retrospective study was conducted with patients' identification through a key terms search within MRI reports in the period of July 2008 to September 2015. Clinical files, MRI, laboratory, and pathology data were reviewed.

RESULTS

Fifty-three patients were identified and 20 were excluded because they did not meet the inclusion criteria. Of the 33 included, 19 were female, with a mean age at symptoms onset of 51.2 ± 17.6 years. The most common presenting symptoms were headache and cranial nerves palsy, followed by seizures, delirium, lumbar pain, cognitive decline, motor deficit, and language impairment. In 17 patients, a neoplastic etiology was identified; in eight, inflammatory/autoimmune; in six, infectious; and two were classified as idiopathic. Of the eight patients with inflammatory/autoimmune etiology, four had possible IgG4-related disease (IgG4-RD) and the remaining had granulomatosis with polyangiitis, sarcoidosis, rheumatoid arthritis, and Tolosa-Hunt syndrome. Treatment was directed according to the underlying etiology.

DISCUSSION

In the described series, a female predominance was identified, with symptoms' onset in the 5th decade. Although headache was the most common symptom, clinical presentation was varied, emphasizing the role of MRI in HP diagnosis. The underlying etiologies were diverse, with only a few cases remaining idiopathic, also reflecting the contribution of the recently described IgG4-RD.

Focal status epilepticus as a manifestation of idiopathic hypertrophic cranial pachymeningitis

BACKGROUND

Idiopathic hypertrophic cranial pachymeningitis (IHCP) is an uncommon disease of unknown etiology characterized by thickening of the cerebral dura mater with possible associated inflammation. The most frequently described clinical symptoms include headache, cranial nerve palsy, and cerebellar dysfunction. Epilepsy and/or status epilepticus as main presentation is very uncommon.

CASE PRESENTATION

Two consecutive cases are presented of patients manifesting focal status epilepticus secondary to IHCP, with clinical, laboratory [blood test and cerebrospinal fluid (CSF) analysis], neuroradiologic [magnetic resonance imaging (MRI) at 3 Tesla and digital subtraction angiography (DSA)], and therapeutic data. One patient underwent meningeal biopsy; pathology findings are also included. Corticosteroid therapy resulted in clinical improvement in both cases, and neuroimaging showed decreased abnormal morphology, compared to initial findings.

CONCLUSION

In the diagnostic approach to focal status epilepticus or epilepsy, IHCP must be considered a potential, although extremely infrequent, cause. Anti-inflammatory treatment is an effective addition to antiepileptic drug therapy in patients with IHCP.

Neuro-Behçet's Disease Presenting as Hypertrophic Pachymeningitis

A 25-year-old man presented with blurred vision and chronic headache. His brain MRI revealed bilateral frontal pachymeningeal enhancement with leptomeningeal enhancement. The patient had experienced recurrent oral ulcer and had anterior uveitis and papulopustules skin lesion. We diagnosed him with hypertrophic pachymeningitis (HP) associated with neuro-Behçet's disease (NBD). There have been few reports describing HP in patients with NBD. We report a case of NBD presenting as HP.

Arachnoid involved in idiopathic hypertrophic pachymeningitis

The cerebrospinal fluid (CSF) shows inflammatory changes in patients with idiopathic hypertrophic pachymeningitis (IHP), which is a rare disorder. However, systemic CSF research including immunoglobulins in patients with IHP are substantially lacking. In the study, clinical, laboratory, neuroradiologic and therapeutic data from 9 patients with IHP were retrospectively studied, and CSF changes were analyzed. Intracranial pressure was elevated in 4 patients. Protein levels in CSF were elevated in 5 patients (< 1g/L). IgA was elevated in 7 patients (> 0.5mg/dL), IgG was elevated in 8 patients (> 3.4 mg/dL) and IgM was elevated in 6 patients (>0.13 mg/dL) with IHP. CSF immunoglobulins, including IgA, IgG and IgM, were significantly elevated compared with levels in the control (P = 0.021, 0.018, 0.019). There were no linear correlations between IgG, IgM and protein in CSF, but there was a linear correlation between IgA and protein. In conclusion, CSF in IHP shows inflammatory changes, and protein levels are low to moderately elevated. CSF immunoglobulins, including IgA, IgG and IgM, also increased. The arachnoid is involved in IHP, a proportion of immunoglobulins may originate from the blood because of damage to the blood-CSF barrier at the arachnoid. Other intrathecal synthesis of immunoglobulins may be a secondary change due to alteration in the CSF's content to stabilize the internal environment or may be secreted by activated immune memory cells in the brain, which need further research.

Neurosarcoidosis: guidance for the general neurologist

Neurosarcoidosis (NS) more commonly occurs in the setting of systemic disease. The diagnosis is based on a clinical history suggestive of NS, presence of noncaseating granulomas, and supportive evidence of sarcoid pathology, laboratory, and imaging studies. NS could involve any part of the nervous system and often demands high doses of steroids for symptom control. It presents low response to isolated steroids administration and frequently requires immunosuppressive agents. In NS, lymphocytes are polarized toward an excessive Th1 response, leading to overproduction of TNF-alpha and INF-gama, as well as lL-2 and IL-15. Infliximab, a chimeric monoclonal antibody that neutralizes the biological activity of TNF-alpha, is a new option in the NS treatment. We revised pathophysiology, clinical manifestations, diagnostic work up, and treatment of NS as guidance for the general neurologist.

[Recurrent idiopathic hypertrophic pachymeningitis after surgery of chronic otitis media with cholesteatoma: a case report]

A 70-year-old woman visited our hospital because of a chronic headache four years ago. MRI demonstrated almost symmetrically thickened dura mater in the frontal and parietal regions. She was diagnosed with idiopathic hypertrophic pachymeningitis and received corticosteroid therapy. Corticosteroid therapy improved her clinical symptoms and thickening of the dura mater. She remained free of neurological symptoms after prednisolone was tapered to 5 mg/day. However, three years ago, she developed ear pain, otorrhea and hearing loss on the left side. She was diagnosed as having otitis media with cholesteatoma last year, and underwent mastoidectomy and tympanoplasty on the left side three months ago. After surgery, she recovered from the ear symptoms, but noticed a headache on the left side. Three months after the surgery, MRI demonstrated the recurrence of hypertrophic pachymeningitis in the frontal and parietal regions, particularly on the left side. Corticosteroid therapy again improved the headache and thickening of the dura mater. The finding that the patient recovered after corticosteroid therapy alone suggests that non-infectious inflammation played a major role in the pathogenesis. Chronic inflammation associated with otitis media with cholesteatoma or surgical invasiveness might induce the recurrence of idiopathic hypertrophic pachymeningitis.

A case of idiopathic hypertrophic cranial pachymeningitis presenting high values of matrix metalloproteinase

This report concerns a 53-year-old male patient with idiopathic hypertrophic cranial pachymeningitis who presented with multiple cranial nerve palsies (I, II, III, IV, V, VI). Brain magnetic resonance imaging showed diffuse thickening and gadolinium enhancement of the cerebral dura mater. A biopsy of the cerebral dura mater showed granulomatous vasculitis with histiocyte infiltration. Although both the serum rheumatoid factor (RF) and matrix metalloproteinase-3 (MMP-3) were high, the patient showed no signs of arthritis. He was anti-cyclic citrullinated peptide antibody negative, which makes the presence of comorbid chronic rheumatoid arthritis (RA) unlikely. The aetiology of the pachymeningitis was unknown, which led to the diagnosis of idiopathic hypertrophic cranial pachymeningitis. Steroid pulse therapy successfully diminished the patient's pachymeningitis and lowered both RF and MMP-3. High values of RF suggest the possible involvement of an autoimmune mechanism, and the MMP value may be an important indicator of the aetiology of pachymeningitis with granulomatous vasculitis.

Painful ophthalmoplegia caused by idiopathic hypertrophic cranial pachymeningitis in the cavernous sinus

A 73-year-old man presenting with painful unilateral ophthalmoplegia is reported. Magnetic resonance imaging demonstrated a mass in the cavernous sinus extending to the floor of the middle cranial fossa. After resection of the lesion and anti-tuberculous chemotherapy his symptoms improved. Pathological examination revealed extensive caseous necrosis.

Character changes from idiopathic cranial pachymeningoencephalitis

A 66-year-old man with idiopathic cranial pachymeningoencephalitis was described. He suffered from left orbital pain, and character changes. He became short tempered, and was very attached to trifles. Two years prior to these symptoms, he had developed transient left abducent nerve palsy. Head MRI showed a thickening and enhancement of the dura mater on gadolinium-enhanced T1-weighted images, and high signal intensity lesions at bilateral frontal lobes predominantly in the white matter on T2-weighted images. Biopsies revealed microglial proliferation in the cerebral parenchyma, and mild lymphocytic perivascular infiltration. No evidence of intracranial infection was detected. We therefore treated him with methylprednisolone pulse therapy followed by oral prednisolone. His character became gradually normalized, and bilateral frontal lobe lesions seen on MRI disappeared. This is the first case to describe recurrent pachymeningoencephalitis with character changes, and symptoms were probably due to frontal lobe dysfunction.

Hypertrophic pachymeningitis and undifferentiated connective tissue disease: a case report and review of the literature

A 63-year-old man with hypertrophic pachymeningitis (HP) and an undifferentiated connective tissue disease is described. Combined therapy with prednisolone and azathioprine improved his symptoms. The association between an undifferentiated connective tissue disease and HP is discussed.

Clinical and magnetic resonance imaging manifestations of neurosarcoidosis

OBJECTIVES

To describe clinical and neuroimaging manifestations of neurosarcoidosis in a cohort of 21 patients.

PATIENTS AND METHODS

We reviewed records of 21 patients with sarcoidosis and central nervous system (CNS) manifestations referred to Cooper University Hospital, with emphasis on neuroimaging findings and associated clinical and laboratory evidence of sarcoidosis. Nineteen patients were categorized as having "definite," "probable," or "possible" neurosarcoidosis, while 1 had associated CNS vasculitis and another had Hodgkins lymphoma with cauda equina syndrome.

RESULTS

The most common manifestations included myelopathy, cranial neuropathies, and encephalopathy. In 6 patients, CNS biopsy showed sterile, noncaseating granuloma (NCG), while in the remainder, the diagnosis was established through a combination of clinical, radiographic, and laboratory findings. Notably, 10 patients developed acute neurological emergencies, including seizures, spinal cord compression, and increased intracranial pressure. Findings on magnetic resonance imaging (MRI) included a variety of manifestations, including isolated mass lesion, diffuse intraparenchymal inflammatory lesions in the brain and spinal cord, leptomeningeal enhancement, hydrocephalus, and intracranial hemorrhage.

CONCLUSIONS

Sarcoidosis is associated with diverse neurological manifestations and neuroimaging findings. The diagnosis of isolated CNS sarcoidosis requires a biopsy to document the presence of sterile NCG and to exclude neoplasms and other granulomatous diseases. When a biopsy of the CNS is not possible, a diagnosis of neurosarcoidosis can reasonably be supported in many patients by MRI findings and exclusion of other disorders.

RELEVANCE

Optimum management of patients with neurosarcoidosis relies on the ability of clinicians to recognize the broad spectrum of clinical and neuroimaging manifestations of the disorder.

Imaging of the temporal bone

Classical descriptions of the temporal bone are based on its five embryologically distinct osseous components: the petrous, tympanic, mastoid, squamous, and styloid portions.

Idiopathic Hypertrophic Cranial Pachymeningitis Associated With Total Occlusion of the Dural Sinuses-Case Report-

A 44-year-old man presented with a rare case of idiopathic hypertrophic cranial pachymeningitis manifesting as generalized seizure. Neuroimaging and pathological examinations showed the typical features of hypertrophic cranial pachymeningitis. Tuberculosis was a possible cause based on the positive purified protein-derived skin test, but the origin of the disease was not confirmed by further examinations. Cerebral angiography showed total occlusion of the dural sinuses with development of the emissary veins. Histological examination of the dura showed thickening of the fibrous tissue with rare inflammatory cells, suggestive of the extremely long duration of the disease. The diagnosis was idiopathic hypertrophic cranial pachymeningitis, but was treated only with anticonvulsants. The disease did not progress during follow up of 3 years. Idiopathic hypertrophic cranial pachymeningitis may have various causes related to unusual forms of infectious or autoimmune disorders.

Leptomeningeal metastases

LM is an increasingly common neurologic complication of cancer with variable clinical manifestations. Although there are no curative treatments, currently available therapies can preserve neurologic function and potentially improve quality of life. Further research into the mechanisms of leptomeningeal metastasis will elucidate molecular and cellular pathways that may allow identification of potential targets to interrupt this process early or to prevent this complication. Animal models are needed to further define the pathophysiology of LM and to provide an experimental system to test novel treatments [242-245]. There is an urgent need to develop new drug-based or radiation-based treatments for patients with LM. Randomized clinical trials are the appropriate study design to determine the efficacy of new treatments for LM. However, surrogate markers for response must be developed to facilitate the identification of effective regimens. Survival is not the optimal end point for such studies as most patients who develop this complication already have advanced, incurable cancer. Prevention of or delay in neurologic progression is one objective that has been utilized in recent randomized trials in patients with LM, and this end point deserves further attention. Although the development of LM represents a poor prognostic marker in patients with cancer it is important for physicians to recognize the symptoms and signs of the disease and establish the diagnosis as early in the disease course as possible. This may provide an opportunity for effective intervention that can improve quality of life, prevent further neurologic deterioration and, for a subset of patients, improve survival.

Dural lesions mimicking meningiomas

Recently, a number of neoplastic and nonneoplastic entities have been reported that radiographically and clinically mimic meningiomas. Because these lesions occur infrequently and may resemble a meningioma during intraoperative analysis, they may not be considered in the differential diagnosis. This review (and case illustrations) considers some of the newly recognized and notable lesions that can mimic meningiomas, including solitary fibrous tumors, gliosarcomas, leiomyosarcomas, hemangiopericytomas, melanocytomas, Hodgkin's disease, plasmacytomas, inflammatory pseudotumors, neurosarcoidosis, plasma cell granulomas, Rosai-Dorfman disease, Castleman's disease, xanthomas, rheumatoid nodules, and tuberculomas. Awareness that these lesions involve the dura may facilitate intraoperative recognition and, in some cases, preclude unnecessary additional surgery.

Idiopathic hypertrophic cranial pachymeningitis associated with Sweet's Syndrome

A case of hypertrophic cranial pachymeningitis associated with Sweet's Syndrome is presented. Both entities have been described in association with several other chronic systemic inflammatory diseases and autoimmune conditions. To our knowledge the coexistence between Sweet's Syndrome and hypertrophic cranial pachymeningitis has not been reported up to date. We suggest a possible autoimmune or dysimmune mechanism in the pathogenesis of these two entities.

Necrotizing neurosarcoidosis of the cranial base resembling an en plaque sphenoid wing meningioma: case report

OBJECTIVE AND IMPORTANCE

Necrotizing sarcoid granuloma (NSG) has been recognized as a histological variant of sarcoidosis. Two cases of neurosarcoidosis (NS) with NSG with concomitant systemic disease have been described previously. We present an unusual case of primary NS-NSG that resembled an en plaque cranial base meningioma.

CLINICAL PRESENTATION

A 51-year-old man presented with a 3-month history of progressive left visual deterioration and proptosis. Brain magnetic resonance imaging demonstrated a large cranial base lesion occupying the left anterior clinoid process and sphenoid wing, extending to the left frontotemporal convexity. A second dura-based lesion was observed in the right parietal convexity. Both lesions enhanced homogeneously after administration of intravenous contrast medium. Magnetic resonance imaging characteristics were consistent with a typical clinoidal meningioma with an en plaque extension laterally.

INTERVENTION

A left frontotemporal craniotomy with extradural removal of the anterior clinoid process was performed. When the dura was opened, a red fibrous mass was identified. Intraoperative histological analysis revealed the presence of necrotizing and noncaseating granulomas. Postoperatively, cerebrospinal fluid, erythrocyte sedimentation rate, C-reactive protein, and serum and cerebrospinal fluid angiotensin-converting enzyme values were normal. The search for acid-fast bacilli or fungi was negative. A diagnosis of primary NS-NSG was made. The patient began long-term high-dose corticosteroid therapy. One and a half years after surgery, his vision had improved significantly and the lesions were stable as revealed by magnetic resonance imaging.

CONCLUSION

The first case of primary NS-NSG in the absence of systemic sarcoidosis is reported. NS should be included in the differential diagnosis of dura-based lesions resembling meningioma.

Imaging of the temporal bone

Classical descriptions of the temporal bone are based on its five embryologically distinct osseous components: the petrous, tympanic, mastoid, squamous, and styloid portions.

Primary cerebral sarcoid granuloma: the importance of definitive diagnosis in the high-risk patient population

Sarcoidosis of the central nervous system has been variously reported in 5-15% of all sarcoid patients. However, presentation of sarcoidosis as an isolated 'intracranial tumor' is rare. A 35-year-old African-American woman presented with intractable headaches. Neuroimaging revealed a tumor that was suggestive of a glioma or meningioma or metastasis. The symptoms did not respond to steroids, and an open biopsy of the lesion revealed non-caseating granuloma. A thorough work-up for systemic sarcoidosis was negative. The patient remains symptom-free at a 2-year follow-up. Primary sarcoid granuloma of the brain is rare. Once systemic disease has been excluded, early tissue diagnosis is crucial. This is particularly relevant for patients in the high-risk population before considering empirical radiosurgery.

Diagnosis and management of neurosarcoidosis

Sarcoidosis is a multisystemic disorder characterised by the presence of multiple noncaseating granulomas. Clinically recognisable nervous system involvement occurs in 5-16% of patients with sarcoidosis. However, the incidence of subclinical neurosarcoidosis may be higher. The following article presents a review of the disease, including its pathophysiology, clinical and radiological characteristics and treatment. Neurosarcoidosis should be included in the differential diagnosis of infectious and noninfectious neurological syndromes.

Imaging evaluation of sensorineural hearing loss

The imaging evaluation of patients with sensorineural hearing loss (SNHL) focuses on the acoustic pathways from the cochlea to the auditory cortex. Magnetic resonance imaging (MRI) is the modality of choice for most patients with SNHL, though computed tomography (CT) also plays an important role in the evaluation of bony changes and in patients for whom MRI is contraindicated. Conventional enhanced MRI is the most commonly used technique in this clinical setting. High-resolution fast spin-echo T2 MRI is an adjunctive technique that provides exquisite evaluation of the cerebellopontine angle (CPA), internal auditory canal (IAC), cranial nerves, and membranous labyrinth, and plays a significant role in the diagnosis and surgical evaluation of SNHL. Categories of lesions that cause SNHL include brain lesions involving central auditory pathways; neoplasms of the CPA and IAC, the most common being schwannoma; other neoplastic, congenital, and cystic masses of the CPA and IAC; congenital anomalies of the inner ear; intrinsic cochlear nerve defects, inflammatory processes of the inner ear; and temporal bone trauma.

Neurosarcoidosis without systemic sarcoidosis--case report

A 20-year-old male presented with symptoms of isolated neurosarcoidosis including epilepsy. Magnetic resonance imaging disclosed multiple enhanced right temporal and frontal lesions. Cerebrospinal fluid examination identified mild lymphocytic pleocytosis, and histological examination of a stereotactic brain biopsy specimen demonstrated noncaseating granulomas, so fungal or other inflammatory or granulomatous diseases were excluded. The diagnosis was cerebral sarcoidosis, despite the absence of systemic manifestations. Corticosteroid therapy improved his neurological state and radiological findings. Neurosarcoidosis is a well-recognized occurrence in systemic sarcoidosis, but diagnosis may be difficult in the absence of extracerebral manifestations.

Idiopathic hypertrophic pachymeningitis: a report of two patients and review of the literature

PURPOSE

We report the treatment and follow-up, including MRI, of two patients with idiopathic hypertrophic pachymeningitis and review the English language literature, with emphasis on management and outcome in this rare disorder.

METHODS AND MATERIALS

The files of two patients were reviewed, with relevant histopathology and imaging (MRI). The first patient has been followed for sixteen years (the longest MRI-documented postoperative course reported for this condition) and the second for two years. The English language literature was reviewed, including a summary of all reported patients that have been followed with MRI or CT imaging.

RESULTS

Despite extensive investigation, no underlying etiology was determined in either patient. Histopathological studies revealed a chronic inflammatory dural infiltrate in both patients, with granulomas in the first but not the second patient. The first patient underwent surgery twice and has remained stable for sixteen years, despite persistent neurologic deficits. The second patient was managed with dexamethasone after a surgical biopsy, and experienced complete resolution of all neurological deficits and abnormalities seen with MRI.

CONCLUSIONS

Although prompt and extensive surgery has been recommended for this condition, the results from our second patient indicate that complete remission can be achieved in some patients with biopsy and steroid therapy. This also supports the view that autoimmune mechanisms underlie idiopathic hypertrophic pachymeningitis. The first patient illustrates that extensive laminectomies may be an effective therapeutic option but chronic discomfort may result. If extensive surgery must be performed, laminoplasty should be done because of the potential for reduced pain and improved long-term spinal stability.

MR of CNS sarcoidosis: correlation of imaging features to clinical symptoms and response to treatment

BACKGROUND AND PURPOSE

Sarcoidosis is an idiopathic systemic granulomatous disease, recognized in a patient when clinical and radiologic findings are confirmed by histopathologic analysis. The objective was to identify a relationship between MR imaging and clinical findings in CNS sarcoidosis.

METHODS

The clinical charts of 461 patients with biopsy-proved sarcoidosis were reviewed retrospectively. Criteria for including patients in the study included those with symptoms referable to the CNS, excluding those with another explanation for their symptoms, those with headaches or other subjective complaints without accompanying objective findings, and those with peripheral neuropathy other than cranial nerve involvement or myopathy without CNS manifestations. Thirty-four of 38 patients whose conditions met the criteria for CNS sarcoidosis underwent a total of 82 MR examinations. The positive imaging findings were divided into categories as follows: pachymeningeal, leptomeningeal, nonenhancing brain parenchymal, enhancing brain parenchymal, cranial nerve, and spinal cord and nerve root involvement. Treatment response, clinical symptomatology, and any available histopathologic studies were analyzed with respect to imaging manifestations in each of the categories.

RESULTS

Eighty-two percent of the patients with sarcoidosis with neurologic symptoms referable to the CNS had findings revealed by MR imaging. However, eight (40%) of 20 cranial nerve deficits seen at clinical examination of 13 patients were not seen at contrast-enhanced MR imaging, and 50% of the patients with symptoms referable to the pituitary axis had no abnormal findings on routine contrast-enhanced MR images. In contradistinction, 44% of 18 cranial nerves in nine patients with MR evidence of involvement had no symptoms referable to the involved cranial nerve. Clinical and radiologic deterioration occurred more commonly with leptomeningeal and enhancing brain parenchymal lesions.

CONCLUSION

MR imaging can be used to confirm clinical suspicion and to show subclinical disease and the response of pathologic lesions to treatment.

[Cranial pachymeningitis]

INTRODUCTION

Pachymeningitis is a fibrous inflammatory process with non-specific symptoms, involving the dura mater. Due to MRI development, diagnosis is both easier and earlier.

CURRENT KNOWLEDGE AND KEY POINTS

We report seven cases and review current literature. Clinical features are headaches and cranial nerve palsies. CSF shows inflammatory changes, while MRI evidences thickening of the dura mater. Disease etiologies in the present study were tuberculosis in two cases, sarcoidosis, Lyme disease, lymphoma and dural puncture; in one case only the disease was of unknown origin. The condition of six patients improved with specific treatment.

FUTURE PROSPECTS AND PROJECTS

Further MRI development should allow detection of new forms of pachymeningitis and standardization of patients' management through the study of more important series.

The pitfall of silent neurosarcoidosis

Sarcoidosis in childhood is seldom reported. Most cases are observed in older children and preadolescents as bilateral pulmonary disease and eye lesions. Arthritic features are more likely to be observed in infants and children younger than 4 years of age who do not develop pulmonary disease. Neurosarcoidosis is exceptional in this age group and seldom suspected when the neurologic symptoms are present. The authors report a pediatric patient with systemic sarcoidosis who developed a severe but silent neurologic involvement. Numerous masslike lesions were discovered on systematic cranial magnetic resonance imaging. The authors recommend a complete screening of extrapulmonary manifestations in children with sarcoidosis. The proper management of patients with incidentally discovered neurosarcoidosis has yet to be established.

A 67-year-old woman with polymyalgia rheumatica and left hemispatial neglect

A 67-year-old woman with a diagnosis of polymyalgia rheumatica presented initially with periods of confusion and incontinence. A CT scan of the brain was normal and she was treated with tapering doses of corticosteroids and clinical improvement. After a brief period off steroids, the patient presented with a progressive dementia, left-sided clumsiness, gait disturbances and left hemispatial neglect. An MRI at this time demonstrated a large area of edema over the right parietal lobe and intense cortical enhancement. A chest CT demonstrated multiple nodules. Biopsies of the lung and brain failed to identify any infectious organisms or malignant tissue. The leptomeningeal biopsy revealed multiple granulomatous areas with central necrosis and hystiocytic cells consistent with idiopathic hypertrophic pachy-meningitis.

Parafalcine and bilateral convexity neurosarcoidosis mimicking meningioma: case report and review of the literature

OBJECTIVE AND IMPORTANCE

Sarcoidosis is a granulomatous disorder of unknown origin that may rarely present solely as an intracranial tumor. Neurosarcoidosis can mimic more common disease processes, such as meningioma, glioma, or metastases. It is important to keep neurosarcoidosis in mind, both preoperatively and intraoperatively, to guide appropriate treatment. We present a case of neurosarcoidosis mimicking a parafalcine and bilateral convexity meningioma.

CLINICAL PRESENTATION

A 44-year-old African-American woman was referred to our institution with a diagnosis of meningioma based on a 4-month history of headaches, decreased memory, personality changes, and decreased coordination and on the results of axial computed tomography, which revealed a parafalcine and bilateral convexity mass.

INTERVENTION

Cerebral arteriography and magnetic resonance imaging were performed to better characterize the lesion for anticipated surgery. Despite corticosteroid therapy, the patient continued to have progressive symptoms and underwent surgery. Intraoperative frozen sections were consistent with neurosarcoidosis. The mass was then significantly debulked unilaterally.

CONCLUSION

Laboratory studies and follow-up examinations revealed no evidence of systemic sarcoidosis. The patient received corticosteroid therapy and subsequently improved. Serial magnetic resonance imaging examinations during several months revealed decreasing tumor size.

Sarcoidosis en-plaque. Report of a case and review of the literature

A 31-year-old black male with sarcoidosis en-plaque of the dura mater, which is a rare morphological variant of neurosarcoidosis (NS), presented at our clinic. Magnetic resonance imaging (MRI) of the head with gadolinium showed non-specific enhancement of both tentorial leaves extending to the floor of right middle cranial fossa and cavernous sinus. The laboratory results were normal except for slightly increased serum angiotensin converting enzyme (SACE) (68 U/ml n = 4-56 U/ml) and cerebrospinal fluid (CSF) IgG index (0.57, n = 0.46). Biopsy of the intracranial dural lesion was consistent with sarcoidosis. Oral steroid therapy (Methylprednisolone 4 mg QID) was started and the patient became asymptomatic. However, MRI of the brain with gadolinium 2 months after biopsy showed progression and extension of the enhanced dural lesion. His SACE level was unchanged. We concluded that progression of the enhanced lesion seen in MRI could be recently formed scar tissue, new lesion or both. MRI findings should always be correlated with clinical findings for evaluation of NS during follow-up.

Pathogen-free granulomatous diseases of the central nervous system

Pathogen-free granulomatous diseases (PFGD) of the central nervous system (CNS) are a group of disorders with protean clinical and pathological findings. Failure to identify a causative organism leads to considerable diagnostic difficulty. The neuropathology records between 1985 and 1995 were retrospectively reviewed, and the medical records of all patients in whom a diagnosis of PFGD of the CNS was made were retrieved. Patients in whom an infective agent was shown either by culture, special staining techniques, or by immunohistochemical methods were excluded. We identified 11 patients (eight male, three female) who fulfilled the pathological criteria for this condition. Average age at diagnosis was 38.7 years (range, 17 to 78). Neurological symptoms were the presenting feature in nine patients. Neuroimaging findings included hydrocephalus (54.5%), meningeal enhancement (45.5%), and mass lesions (45.5%). Seven patients had antemortem CNS biopsies (brain/meninges [n = 6], spinal [n = 1]), which showed noncaseating granulomas. Eight patients died (mortality rate: 72.7%). Postmortem examination showed granulomatous involvement of the leptomeninges and cerebral parenchyma in all cases with systemic involvement in 50%, chiefly in the form of noncaseating granulomas of the hilar nodes. Six patients fulfilled the clinical, radiological, and pathological diagnostic criteria for neurosarcoidosis. The remaining five patients had an unclassifiable pathogen-free granulomatous disease of the CNS. PFGD of the CNS are associated with a poor prognosis. Although neurosarcoidosis may account for some of the cases, there remains an unclassifiable subgroup that continues to be a diagnostic and management challenge.

"Idiopathic" cranial hypertrophic pachymeningitis responsive to antituberculous therapy: case report

OBJECTIVE AND IMPORTANCE

We present a case similar to previously described cases of idiopathic hypertrophic cranial pachymeningitis. However, our patient responded to antituberculous therapy. This raises the possibility that some cases of "idiopathic" hypertrophic cranial pachymeningitis may represent occult tuberculous disease.

CLINICAL PRESENTATION

A 55-year-old woman presented with a right fourth nerve palsy and a 5-month history of headaches. Magnetic resonance imaging with gadolinium revealed thick enhancing dura on the right half of the tentorium cerebelli, with edema of the adjacent midbrain, pons, and cerebral peduncle.

INTERVENTION

Open biopsy of the tentorial lesion revealed only dense fibrosis with histiocytic infiltration. An exhaustive search failed to demonstrate an underlying cause. In particular, mycobacterial stains/cultures were negative, there was no granuloma formation, and the chest x-ray was unremarkable. However, because of a strongly positive purified protein-derivative skin test and residence in an area endemic for tuberculosis, the patient was placed on antituberculous medications.

CONCLUSION

The patient's symptoms and signs resolved with antituberculous therapy. Resolution of the tentorial lesion was confirmed by gadolinium-enhanced magnetic resonance imaging. We conclude that this case represented occult tuberculous disease. An empiric trial of antituberculous therapy may be warranted in other cases of apparently idiopathic hypertrophic cranial pachymeningitis.

Spectrum of sarcoidosis involving the eye and brain

PURPOSE

To illustrate the spectrum of sarcoidosis involving the eye and brain and the difficulties of confirming its clinical diagnosis.

METHODS

The presentation of two unusual case reports of patients with ocular and cerebral involvement with sarcoidosis.

RESULTS

Tissue biopsy, an essential component in the differential diagnosis, was required to confirm the diagnosis of sarcoidosis in each patient.

CONCLUSIONS

Sarcoidosis remains an enigmatic disease with protean manifestations and widely differing outcomes.

Idiopathic cranial pachymeningoencephalitis focally affecting the parietal dura mater and adjacent brain parenchyma: case report

OBJECTIVE AND IMPORTANCE

Cranial pachymeningitis is a typically diffuse granulomatous disease, which often affects the tentorium and falx. We report a rare case of idiopathic cranial pachymeningoencephalitis focally affecting only the left parietal dura mater and adjacent inferior parietal lobule.

CLINICAL PRESENTATION

A 46-year-old woman, with no history of disease, suddenly had a generalized convulsion. A gadolinium-enhanced T1-weighted magnetic resonance image showed homogeneously stained meninges extending to the cortical parenchyma with marked perifocal edema. The thickened dura was visualized as a hypointense area on a T2-weighted magnetic resonance image.

INTERVENTION

The patient underwent successful en bloc excision of the mass involving the dura mater and adjacent brain parenchyma. Histological examination of the dura mater revealed large numbers of chronic and acute inflammatory cells. These cells were also present in the subarachnoid and Virchow-Robin spaces and part of the brain parenchyma in the resected cortex. After the operation, the patient experienced no neurological deficits or recurrent mass for 10 months.

CONCLUSION

Early diagnosis of pachymeningitis using magnetic resonance imaging is important for the treatment of pachymeningoencephalitis, because diffuse involvement of the dura mater and brain parenchyma can make en bloc excision difficult.

[Sarcoidosis of the central nervous system: clinical and radiological polymorphism]

Central nervous system (CNS) neurosarcoidosis was considered to be infrequent. Clinical and radiological polymorphism explained the delay before diagnosis. With magnetic resonance imaging (MRI), diagnosis is more easily performed, especially in paucisymptomatic cases. A review of the most important clinical and radiological studies and three personal cases are reported. This underlines variable characteristics of hemispheric localizations, especially pseudotumoral forms.

Meningeal granulomas: sarcoidosis or tuberculosis? Differentiation can be difficult

Images

Spontaneous resolution of hypertrophic cranial pachymeningitis

A 36-year-old woman presented suffering from severe headache and diploia. Magnetic resonance imaging showed a diffuse thickening of the cranial dura mater which was enhanced by gadolinium-DTPA. Two months later, an improvement of the clinical symptoms and a spontaneous resolution of the dural thickening were noted. Hypertrophic cranial pachymeningitis and other diseases causing diffuse dural thickening are discussed.

Idiopathic chronic hypertrophic craniocervical pachymeningitis: case report

A 55-year-old woman with a unique form of chronic hypertrophic pachymeningitis involving the posterior fossa and upper cervical spine is reported. Unlike other cases previously described, the clinical picture was dominated by signs of increased intracranial pressure, lower cranial nerve disorders, and a progressive cervical radiculomyelopathy. The diagnosis was made by means of a contrast-enhanced magnetic resonance imaging scan and confirmed by histological examination of the excised dura. Surgical treatment with removal of the hypertrophic dura provided temporary relief, although the natural history of the disease was not modified. Exhaustive bacteriological and histopathological studies failed to identify a specific cause for this diffuse hypertrophy of the cranial and cervical dura. The literature is reviewed, and other histologically documented cases are discussed.