Sarcoidosis mimicking glioma: case report and review of intracranial sarcoid mass lesions

[Neurosarcoidosis of the anterior visual pathway (a case report and literature review)]

Sarcoidosis is a multisystem granulomatous disorder of unknown nature. Patients often present with pulmonary, skin, eye, and orbital lesions. Involvement of the central nervous system (CNS) is accompanied by granulomatous leptomeningitis and damage to the basal brain structures with formation of granulomas near the cranial nerves, hypothalamus, pituitary gland, cavernous sinuses, optic chiasm, and intracranial optic nerves. The optic nerves can be affected independently of the other CNS regions, which may be the first manifestation of the disease. The article presents two clinical cases of sarcoidosis affecting the anterior visual pathway. Diagnosis of the disease was associated with certain difficulties. A biopsy revealed a sarcoidosis lesion.

Overview of neurosarcoidosis: recent advances

Sarcoidosis (SA) is a granulomatous, multisystem disease of unknown etiology. Most often the disease affects lungs and mediastinal lymph nodes, but it may occur in other organs. Neurosarcoidosis (NS) more commonly occurs with other sarcoidosis forms, in 1 % of cases it involves only nervous system. Symptomatic NS occurs but on autopsy study up to 25 % of cases are confirmed. NS can affect central nervous system: the brain, spinal cord and peripheral nerves, and muscles. The diagnosis of neurosarcoidosis facilitates diagnostic criteria: histopathological, imaging and cerebrospinal fluid examination, and clinical symptoms. At present, there are no set standards for treatment of patients suffering from NS. Early therapy of symptomatic patients is recommended. Corticosteroids still are the first line of treatment for NS patients. In cases of steroids resistance, lack of their effectiveness or existence of contraindication to their use, immunosuppressant treatment is recommended. The latest NS algorithm with immunosuppressive treatment is discussed.

Neurosarcoidosis: two case reports with multiple cranial nerve involvement and review of the literature

BACKGROUND

Involvement of the central nervous system is registered in a relatively small number of patients with sarcoidosis. In this article we present two cases with various neurological symptoms that fulfill criteria for neurosarcoidosis (NS). In addition, we review the literature on NS with special attention to isolated cranial nerve involvement.

METHODS AND RESULTS

First patient: Neurological examination identified multiple cranial neuropathy, moderate right-sided hemiparesis, polyradiculoneuritis of the lower limbs and positive meningeal signs. Laboratory tests showed serum and cerebrospinal fluid (CSF) inflammatory abnormalities, with increased values of the angiotensin-converting enzyme (ACE). CSF analysis also showed presence of 9 oligoclonal IgG bands. Brain and spine magnetic resonance imaging (MRI) revealed diffuse meningopathy, and focal granulomatous lesion in the body of the L5 vertebra. Lung sarcoidosis was confirmed by additional diagnostic procedures. The patient was treated with Methylprednisolone and a tapering course of oral Prednisone, which reduced the pain in the back and legs and improved the strength of the right leg. However, the other neurological deficiencies remained. After confirming lung sarcoidosis, the patient received Methotrexate in addition to Prednisone but during the following 2 years the patient's condition progressively worsened and ended in death. Second patient: Neurological findings showed weakness of the right n. oculomotorius and the right n. trochlearis, as well as the right-side face weakness. We found raised level of the ACE in serum and CSF. Thorax high-definition computed tomography (HDCTT) showed ribbon-like domains of discrete changes in the pulmonary parenchyma. MRI of the brain showed multiple white matter lesions. This patient also received Methylprednisolone followed by Prednisone, and after two months, ocular motility normalized.

CONCLUSION

The diagnosis of NS is always a challenge. For this rerason definitive diagnosis requires the exclusion of other causes of neuropathy. Multiple cranial neuropathies should always arouse suspicion of NS.

An intracerebral mass: tuberculosis or sarcoidosis?

Sarcoidosis is an idiopathic, chronic granulomatous disease and it can affect almost any organ. In autopsy series, it has been reported that the central nervous system involvement has occurred in 5-16% of the patients with sarcoidosis, while the neurological symptoms have occurred only in 3-9% of them. A 40-year-old female patient was admitted to the hospital with complaints of aphasia, balance disorder and drowsiness. An intracerebral mass was detected on cranial CT scans and neurosarcoidosis was diagnosed with clinical, radiological and histopathological findings.

Neurosarcoidosis presenting as an isolated mass of the quadrigeminal plate

A rare case of neurosarcoidosis presenting as an isolated quadrigeminal plate mass without systemic manifestation of this disease is reported. This 26-year-old man presented with symptoms of acute intracranial hypertension including headache, morning vomiting as well as a right homonymous hemianopsia. Magnetic resonance imaging (MRI) showed an expansive tectal mass causing hydrocephalus secondary to an aqueductal obstruction. An external ventricular drainage was inserted and the mass, postulated to be a glioma, was removed through an occipital transtentorial craniotomy. Histopathological examination revealed numerous sarcoid granulomas. Postoperative course was relevant for bilateral hypoacusis and tinnitus, blurred vision, bilateral palpebral ptosis and bilateral internuclear ophthalmoplegia. Chest X-ray was normal. Postoperative thoracic computed tomography (CT) scan showed mediastinal adenopathies. Lung function tests were normal. Angiotensin converting enzyme (ACE) cerebrospinal fluid (CSF) blood ratio was normal. Postoperative treatment and follow-up included corticosteroids, serial lung function tests and cerebral MRI. Neurosarcoidosis may present with protean clinical manifestations and unusual radiological features. This rare diagnosis has to be kept in mind when facing isolated intracerebral mass lesions.

Glioblastoma presenting with steroid-induced pseudoregression of contrast enhancement on magnetic resonance imaging

Corticosteroid-induced reduction in contrast enhancement on radiographic imaging is most commonly associated with lymphoma but has been reported in other entities, including glioma. This finding may represent a diagnostic dilemma. Concern that steroid-induced cytotoxicity obscures histological diagnosis of suspected lymphoma may lead to postponement of a biopsy. If glioma is not considered in the differential diagnosis, reduction in tumor contrast enhancement may be misinterpreted as disease regression rather than a transient radiographic change. We report a case of a patient with an enhancing right temporoparietal mass adjacent to the atrium of the lateral ventricle. After treatment with dexamethasone was started, the mass exhibited marked reduction in contrast enhancement, with symptom improvement. The clinical course suggested lymphoma, and surgery was not performed. Subsequent screening for extra-axial lymphoma was negative. Two weeks later, the patient developed worsening symptoms, and repeat T1-weighted imaging showed interval increase in size and enhancement. The findings suggested a possible diagnosis of malignant glioma. The patient underwent a stereotactic-guided craniotomy for excision of the right temporoparietal mass lesion. Final histological diagnosis was glioblastoma multiforme, World Health Organization grade IV.

Neurosarcoidosis

Although neurosarcoidosis seems to occur in only 5% to 10% of patients who have sarcoidosis, it may lead to significant complications. The diagnosis of neurosarcoidosis usually relies on indirect information from imaging and spinal fluid examination. Although MR imaging remains the most sensitive technique for detecting neurologic disease, other tests, including positron emission tomography scanning and cerebral spinal fluid examination, can provide important information. The role of immunosuppressive agents such as methotrexate, cyclophosphamide, and azathioprine has been expanded, and these agents should be considered for the treatment of some manifestations of neurosarcoidosis. Reports of the antitumor necrosis factor agent infliximab suggest that this drug can be helpful for patients who have neurosarcoidosis.

Neurosarcoïdose : état des connaissances

The origins of neurosarcoidosis, a multisystemic granulomatous disease, remain unknown. Nervous system localizations remain rare, but severe. Lymphocytic meningitis, psychiatric disorders, diabetes insipidus and cranial nerve palsy are the most frequent signs. Cerebral fluid test and cervical medullar and cerebral MRI with gadolinium have to be performed first. In some cases, histological evidence of granuloma have to be obtained with neuromuscular, meningeal or cerebral biopsies. Functional impairment and life-threatening conditions require early corticosteroid therapy. In worsening cases or in the event of no therapeutic response or poor tolerance to corticosteroids, other immunosuppressive agents should be associated. Maintenance therapy and most often life long maintenance therapy allow a continuous success while avoiding relapse.

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.

Neurosarcoidosis: a clinical dilemma

Sarcoidosis is an inflammatory multisystem disorder of unknown cause. Practically no organ is immune to sarcoidosis; most commonly, in up to 90% of patients, it affects the lungs. The nervous system is involved in 5-15% of patients. Neurosarcoidosis is a serious and commonly devastating complication of sarcoidosis. Clinical diagnosis of neurosarcoidosis depends on the finding of neurological disease in multisystem sarcoidosis. As the disease can present in many different ways without biopsy evidence, solitary nervous-system sarcoidosis is difficult to diagnose. Corticosteroids are the drug of first choice. In addition, several cytotoxic drugs, including methotrexate, have been used to treat sarcoidosis. The value of new drugs such as anti-tumour necrosis factor alpha will be assessed. In this review we describe the clinical manifestations of neurosarcoidosis, diagnostic dilemmas and considerations, and therapy.

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.

Central nervous system sarcoidosis: follow-up at MR imaging during steroid therapy

PURPOSE

To document the changes observed at sequential magnetic resonance (MR) imaging of sarcoidosis lesions of the central nervous system (CNS) during treatment with corticosteroids.

MATERIALS AND METHODS

The abnormalities detected in 24 patients (mean follow-up, 36 months) were compared before and after therapeutic periods (n = 75) that were divided into attack (high-dose), upkeep (decreased-dose), and minimal (low-dose) periods. Parenchymal lesions were classified as type 1 (enhanced with gadolinium), type 2 (demyelinating), or type 3 (lacunar) and were assessed as regressing, stable, or progressing.

RESULTS

Seven of the 24 patients had several types of lesions. Isolated type 3 lesions (six patients) were the only lesions not associated with neurologic deficit. Type 1 lesions (13 patients) regressed in 22 of 22 attack periods and progressed in nine of 27 upkeep and minimal periods. MR imaging depicted relapses in patients with multifocal CNS involvement or long-standing CNS impairment or in those who had previously received steroid therapy. Type 2 (seven patients) and type 3 (13 patients) lesions remained stable in 68 of 68 therapeutic periods. Type 1 lesions appeared in three patients with type 2 and type 3 lesions during two upkeep and three minimal periods. Findings at follow-up MR imaging contributed to the reintroduction of high-dose corticosteroid therapy in eight patients.

CONCLUSION

MR imaging can be used to differentiate between reversible and irreversible lesions in CNS sarcoidosis. MR imaging can be a useful tool for adjusting treatment to prevent irreversible CNS damage.

Disorders that mimic central nervous system infections

Many noninfectious diseases can cause signs, symptoms, and cerebrospinal fluid (CSF) abnormalities simulating central nervous system (CNS) infection. Infection usually can be excluded in these cases by the judicious use of serologic tests and CSF stains and cultures. Then, the correct diagnosis is typically suggested by the history and the concomitant presence of clinical and laboratory evidence of disease in other organ systems. Occasionally, particularly when such evidence is absent, the distinction requires meningeal or brain biopsy.

Solitary sarcoid granuloma of the cerebellopontine angle: a case report

BACKGROUND

Sarcoidosis involves the nervous system about 5% of the time and usually manifests as a granulomatous inflammation of the basal meninges and hypothalamus. Cases which are strictly isolated to the central nervous system occur infrequently; rarely, they may present as an intracranial mass.

METHODS

We present the case of a solitary sarcoid granuloma at the cerebellopontine angle in a 42-year-old female who presented with headache, facial numbness, and hearing loss.

RESULTS

A suboccipital craniectomy was performed and the lesion was noted to be grossly adherent to the lower cranial nerves and skull base. The lesion was misdiagnosed as a meningioma with preoperative magnetic resonance imaging and intraoperative histology, and perhaps additional morbidity resulted.

CONCLUSION

We present this case in order to demonstrate the importance of differentiating these dural-based lesions and propose that cases of neurosarcoidosis presenting as a solitary granuloma be treated with surgical debulking and immunosuppression.

Sarcoidosis of the eye, orbit, and central nervous system. Role of MR imaging

Sarcoidosis, a systemic disease of unknown cause, frequently involves the eye, orbit, and central nervous system. The MR imaging findings of orbital and optic pathway sarcoidosis may closely resemble several other orbital and intracranial diseases. This article reviews MR imaging findings of sarcoidosis when it involves the eye, orbit, and visual pathways. Careful review of MR findings and other neuroimaging findings and clinical characteristics will reduce the incidence of mistaking optic nerve and chiasmal sarcoidosis for meningioma or glioma.

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.

Cardiac and neurologic dysfunction in sarcoidosis

Clinically apparent involvement of the heart and nervous system occurs in a relatively small number of patients with sarcoidosis. The diagnosis of myocardial and neurological sarcoidosis is difficult because anatomic presence of granulomas without clinical dysfunction is an important feature of sarcoidosis. The chest radiography is abnormal in 8 of every 10 patients with myocardial or neurosarcoidosis. Serum angiotensin-converting enzyme and gallium uptake studies may provide some indication of the extent and severity of the granulomatous process. Corticosteriods are the mainstay of therapy but chloroquine or hydroxychloriquine, methotrexate, and azathioprine are also effective. Prognosis of myocardial and neurological sarcoidosis is poor.

Pathology of sarcoidosis

This article reviews the pathology of sarcoidosis that covers the general and systemic aspects of the disease. Macroscopic and microscopic descriptions of the disease process are given for selected organs.

Sarcoidosis presenting as a central nervous system mass lesion

Neurosarcoidosis occurs in approximately 5% of patients with systemic sarcoidosis. A review of medical literature shows that intracranial mass-like lesions secondary to sarcoidosis are quite rare. CT and MRI scanning would suggest that this manifestation of neurosarcoidosis may be more common than previously realized. We discuss five cases of neurosarcoidosis presenting as an intracranial mass. Empiric corticosteroid treatment can be recommended for cases with CNS mass in the context of systemic sarcoidosis.

[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.

Case report: pseudotumoral brain lesion as the presenting feature of sarcoidosis

Sarcoidosis rarely presents as an intracranial mass lesion. We report the case of a patient presenting a disturbance of cognitive functions in whom CT and MRI demonstrated a large right fronto-temporal mass lesion with contrast enhancement and surrounding marked oedema, highly suggestive of a brain tumour. The diagnosis of neurosarcoidosis was made after stereotactic biopsy of the lesion.

[Rare sites of sarcoidosis: clinical aspects and reflections on the diagnostic approach]

Rare localisations of sarcoidosis, mainly neurological and cardiological ones are in the most cases seriously threatening whether functional or vital prognosis. They are often responsible for a delay in diagnosis or treatment. Concerning young patients, any unexplained neurological or cardiological manifestations should lead to consider the diagnosis of sarcoidosis. When histological evidence is not obtained, in particular in presence of central nervous system localisations. Systemic explorations such as pulmonary radiography, bronchoalveolar lavage, salivary glands biopsies should be performed. In most cases, these localisations will lead to corticotherapy, which, when revealing unsuccessfully, is associated with another immunosuppressive agent.

Subdural mass lesion secondary to sarcoid granuloma MR and CT findings and differential diagnosis

A patient with surgical and neuropathologically confirmed subdural sarcoid granuloma was evaluated using angiography, contrast-enhanced CT and MR. MR images were obtained on a superconducting magnet with T1, intermediate and multi-echo T2 weighted sequences. Review of the 2 prior cases of subdural sarcoid granuloma from the literature evaluated with MR confirm the variable nature of signal intensities of the lesion. MR was most useful in anatomically evaluating the lesion and planning neurosurgical intervention but both CT and MR alone, in this case, did not definitely obviate the other differential diagnosis including meningioma en-plaque, lymphoma, or metastasis.

Cerebral sarcoidosis presenting as supranuclear gaze palsy with hypokinetic rigid syndrome

A 31-year-old man with histologically documented pulmonary sarcoidosis developed a severe hypokinetic rigid syndrome with a supranuclear gaze palsy following recurrent lymphocytic meningitis and occlusive hydrocephalus. Magnetic resonance imaging (MRI) showed multiple hyperintense foci in the CNS, not detectable by computed tomography (CT). Long-term steroid therapy led to clinical complete remission.

A case of hypothalamic sarcoidosis with hypopituitarism and prolonged remission of hypogonadism

A 21-year-old man developed hypopituitarism, with symptomatic hypogonadism and diabetes insipidus (DI), as well as uveitis, retinal vasculitis, and papilledema in association with systemic sarcoidosis. A suprasellar tumor was demonstrated by computed tomography (CT). Although ophthalmic symptoms disappeared with prednisone and the DI was controlled with Desmopressin (DDAVP), the hypogonadism did not improve with human menopausal gonadotropin (HMG) and human chorionic gonadotropin (HCG). In long-term follow-up, the hypogonadism unexpectedly resolved.

Meningeal neurosarcoidosis mimicking convexity en-plaque meningioma

A 34-year old man presented with headaches. Computed tomography scanning revealed an enhancing subdural mass extending from the skull base to the convexity, thought to represent an en-plaque meningioma. Pathologic study revealed extraaxial subdural granulomatous inflammation consistent with neurosarcoidosis.

Neurosarcoidosis causing ventricular loculation, hydrocephalus, and death

Ten years after a diagnosis of sarcoidosis, a 33-year-old woman presented with a severe headache of 5 days' duration. Neuroradiologic evaluation revealed a large cystic lesion of the left temporal lobe, causing a mass effect. An exploratory operation proved the lesion to be a loculated portion of the temporal horn of the lateral ventricle. Drainage of the loculated ventricle relieved the patient's cephalgia. Within 2 months, however, pain in the head recurred and an unsteady, broad-based gait appeared. Reevaluation disclosed hydrocephalus for which a ventriculoperitoneal shunt was inserted. After this procedure, the patient did well neurologically for 1 year, after which seizures, personality changes, incontinence, and disturbance of gait developed. Death occurred after revision of the shunt, and widespread granulomatous disease was found at autopsy. Neurosarcoidosis, with emphasis on intracranial mass lesions in sarcoidosis, is discussed; the role of surgical treatment in some of these lesions, and in hydrocephalus, is stressed.

Presentation of central nervous system sarcoidosis as intracranial tumors

Five cases of sarcoid presenting as an intracranial tumor are reported. In one instance, the lesion presented as a tumor in the cerebellopontine angle, a site not previously reported for the initial presentation of sarcoid isolated to the central nervous system. The role of computerized tomography, surgery, and steroid therapy is discussed. In the absence of pulmonary involvement, serum angiotensin-converting enzyme levels do not appear to be helpful in predicting steroid response.

Rare multiple orbital localizations of sarcoidosis. A case report

We report a case of bilateral orbital sarcoidosis without other systemic lesions. Steroid therapy did not improve the clinical status of the patient.

Central nervous system sarcoidosis

Sarcoidosis may involve the central nervous system (CNS) in approximately 5% of cases. Three levels of neurological involvement are possible and include cranial nerve abnormalities, peripheral neuropathies, and lesions of the brain, spinal cord, and meninges. In addition to abnormal neurological findings, psychiatric presentations of CNS sarcoidosis include symptoms of delirium, dementia, depression, personality changes, and psychosis. The diagnosis usually rests on neurological, psychiatry, and cerebrospinal fluid (CSF) abnormalities with a history of sarcoidosis in other organ systems. The CSF, however, may be normal in as many as 30% of cases. The complexities of the illness and the difficulties that may be encountered in making the diagnosis are illustrated with a case of suspected CNS sarcoidosis that presented with delirium and choreoathetosis. The use of steroids as the mainstay of treatment is also discussed.

The clinical use of platelet scintigraphy with 111-In-oxine

Platelet scintigraphy was performed on 62 patients with cerebral ischaemia. Pathological scintigraphic images were obtained in 29 of the 62 patients. In 79.3% of these 29 patients the scan was abnormal in the vessel clinically affected. Platelet scintigraphy was abnormal in 21 of 34 patients with normal angiogram or only slight atherosclerosis. In patients undergoing antiplatelet therapy, platelet scintigraphy was less often positive than in untreated patients. It is suggested that platelet scintigraphy could be an appropriate technique for detecting small mural thrombi of the carotid artery, which are the source of arterio-arterial emboli, and for controlling the efficiency of antiplatelet therapy.

[Platelet scintigraphy using indium-111]

Platelet scintigraphic examination using indium-111 was performed on 12 patients with cerebral ischemia. Of these patients 5 had a history of TIA, 3 had a prolonged reversible neurologic deficit (PRIND), 3 cases were presented with a completed stroke and 1 patient suffered from a suspected venous thrombosis of the sinus sagittalis superior. In total 8 cases showed pathological platelet accumulations in the vessel clinically affected, 5 extracranially and 3 intracranially. In the other 4 cases the platelet scintigraphy was normal. The cases with TIA showed pathological platelet accumulations in the appropriate vessel, even if the angiogram was normal. On the other hand platelet scintigraphy did not show any abnormality in 2 patients with an occlusion of the carotid artery. So platelet scintigraphy might be useful in the detection of small arterial lesions producing small strokes, and which remain undetected by other diagnostic methods.

Intracranial subdural sarcoid granuloma. Case report

A patient is reported in whom a subdural sarcoid granuloma caused symptoms of an intracranial mass lesion, and disappeared following steroid therapy. Twenty-three previous cases with large intracranial sarcoid granulomas have been documented, a review of these 24 cases leads the authors to conclude that: 1) neither symptoms nor nonhistological diagnostic studies, including computerized tomography, differentiate sarcoid from cerebral neoplasms or other central nervous granulomas; and 2) because sarcoid mass lesions frequently respond well to corticosteroid therapy, surgery should probably be reserved for cases in which there is diagnostic uncertainty, a need for emergency decompression, or lack of response to steroids.