Printer Friendly

Trigeminal neurosarcoidosis: case report and literature review.


Sarcoidosis rarely manifests by involving the cranial nerves exclusively. A 35-year-old woman presented with bilateral cavernous sinus masses and symptoms of trigeminal neuropathy. Computed tomography and magnetic resonance imaging suggested an intracranial tumor, favoring a meningioma. The patient underwent emergent surgical decompression and tumor excision. Histopathology of the resected tumor revealed classic features of sarcoidosis, and she received steroid treatment accordingly. Neurosarcoidosis must be considered in the differential diagnosis of idiopathic cranial neuropathies to avoid unnecessary surgery, since surgery has little, if any, role in the treatment of sarcoidosis. In the absence of primary organ involvement, radiologic diagnosis of cranial nerve sarcoidosis is unreliable; histopathology is required to reach a definitive diagnosis.


Sarcoidosis is an idiopathic, multisystem, granulomatous inflammatory disease that most commonly involves the lungs, skin, and lymph nodes; it rarely manifests by involving the cranial nerves exclusively. The onset of sarcoidosis is usually unifocal, with a remission and relapse course. The relapse may be focal or systemic, involving the primary as well as other organs. Overt involvement of the central nervous system is uncommon, being seen in only 5% of patients. (1,2) We present such a case.

Case report

A 35-year-old hypertensive woman visited the emergency room because of severe headache, mild ataxia, and right-sided eye swelling and pain. She had a 9-month history of frontal headaches, facial numbness, right-sided blurry vision, and eye dryness but denied any diplopia, hearing loss, or nuchal rigidity. A neurologic examination revealed prominent sensory loss in the second branch of the right trigeminal nerve.

An initial computed tomography (CT) scan suggested a Meckel cave neoplasm, such as a meningioma or schwannoma, involving the right cavernous sinus. Magnetic resonance imaging (MRI) revealed a lobulated right-sided tumor in the trigeminal ganglion of the petrous apex, favoring a neoplasm. It extended to the foramen ovale and foramen rotundum, with extension into the cavernous sinus (figure 1). A smaller tumor was seen in the left trigeminal ganglion, with no neurologic manifestation. Based on the evidence of trigeminal nerve compression, the patient was scheduled for an emergency diagnostic and therapeutic (decompression) craniotomy with right Meckel cave tumor excision.

The resected specimen included several fragments of pale gray soft tissue. Intraoperative and permanent histology sections showed large nerve bundles contained within fibroblastic connective tissue, with several small, non-necrotizing epithelioid granulomas present in the fibroconnective tissue. Several large, multinucleated Langhans-type giant cells were present (figure 2), some showing pink, intracytoplasmic asteroid bodies (figure 3, A) and Schaumann bodies (figure 3, B). Histochemical studies (Gomori methenamine silver and acid-fast stains) showed no fungal elements or acid-fast bacilli. Staining for S-100 protein clearly exposed the outlines of the granulomas within the nerve trunk (figure 3,C).

The patient had an uneventful postoperative period and became asymptomatic. After the diagnosis of neurosarcoidosis was rendered, prednisone was started, and a follow-up MRI revealed significant reduction in the size of the mass in the left trigeminal ganglion.



The most common manifestations of central nervous system (CNS) sarcoidosis are cranial nerve deficits (50%), headache (30%), and seizures (10%). (2) Isolated CNS involvement without systemic disease is rare, with an estimated incidence of less than 0.2 per 100,000. (2) When this does occur, it most frequently involves the meninges of the skull base, hypothalamus, and pituitary gland. (2) Sinonasal disease, which can lead to cranial nerve involvement, is a relatively rare occurrence, with a frequency of 12 to 27%. (3)

The facial nerve is the most common of the cranial nerves involved. The involvement is either in connection with meningeal or secondary to parotid involvement by sarcoidosis. (2) The ocular nerve and chiasm are believed to be the second most common cranial nerve sites involved, with the disease manifesting as optic neuritis or papillitis. (4) Engagement of trigeminal nerves (manifesting as sensory deficit and neuralgia) and auditory and cochlear nerves (manifesting as vertigo) is far less common, obscuring the diagnosis of sarcoidosis.


In trigeminal sarcoidosis, the most common symptoms are transient decreased sensation or numbness in the area covered by the involved nerve. Sarcoidosis is considered the most frequent cause of bilateral Bell palsy? Rarely, patients present with severe pain that can be differentiated from other causes of trigeminal neuralgia by its continuous nature. (6) Taste sensation may be involved, but the corneal reflex and motor function of the trigeminal nerve are usually preserved. (6) Involvement of the motor branches of the trigeminal nerve, as seen in the present case, is extremely rare.

Sarcoidosis that exclusively involves the trigeminal nerve is rare; most cases present as secondary involvement in patients with systemic sarcoidosis. To our knowledge, only 5 cases of primary trigeminal neurosarcoidosis have been reported in the literature. (7)

Diagnostic challenges. In radiology studies, sarcoidosis of the trigeminal nerve can be mistaken for other, more common, pathologies in the cranium such as neoplasms (schwannoma, neurofibroma, and meningioma), inflammatory or autoimmune lesions, and cavernous carotid aneurysm. (7) Clinical findings are not usually helpful in the differential diagnosis.

CT is of limited diagnostic value in neurosarcoidosis; the lesion is rarely identifiable as a discrete mass, as it is often equal in density to the normal surrounding neural tissue. Utilization of contrast does not improve the sensitivity. (7)

MRI is more sensitive and a better choice for detecting the existing mass (2,3,7) but has little specificity in determining the nature of the disease. The differential diagnosis for masses identified by MRI is different in brain parenchyma and meningeal involvement. Brain parenchyma sarcoidosis can mimic multiple sclerosis, metastasis, lymphoma, infections, and gliomas of the brain; whereas infections, carcinomatosis, meningioma, leukemic infiltration, lymphoma, and plasmacytoma can mimic meningeal sarcoidosis. (2) In our patient, CT and MRI studies detected a mass effect at the cavernous sinus that was interpreted as a meningioma. In retrospect, the bilateral and symmetrical involvement of the trigeminal nerves in this patient favors a reactive/inflammatory process rather than a neoplasm.


In sarcoid neuropathies, autoimmune and paraneoplastic diseases should also be considered? Serum angiotensin-converting enzyme level and cerebrospinal fluid tests are useful ancillary tests but lack sensitivity and specificity. (9)

Histologically, this disease manifests several small, nononecrotizing aggregates of epithelioid histiocytes surrounded by a rim of lymphocytes. Multinucleated Langhans-type giant cells are encountered frequently. Small areas of necrosis maybe present. (6) The most marked histologic finding in neurosarcoidosis is lymphoplasmacytic infiltration of the nerve trunk, sometimes accompanied by well-defined granulomas. In cases with optic nerve involvement, granulomas are more commonly seen surrounding the vessels. (10)

In the chronic phase of the disease, a fibrous response develops and surrounds the granulomas. The histologic differential diagnosis includes Wegener granulomatosis, granulomatous angiitis, infections (mycobacterial, fungal, and spirochete), and foreign body reaction following trauma or surgery. (2)

The disease follows a remission and relapse course much like that of multiple sclerosis. Accordingly, from a histologic standpoint, the granulomas can disappear and reappear at various disease intervals. (3)

Treatment. Treatment of sarcoidosis depends on the extent and severity of the disease. After determining which organ(s) is/are involved, corticosteroid or immunosuppressive therapy is commenced as soon as possible, commonly through an oral route.

Although the gold standard diagnostic test is histologic evaluation of the involved tissue through biopsy, surgery has no role in the treatment strategy. Several studies have suggested a conservative approach, such as sequential follow-up with MRI (6,11); most have prohibited surgery because the lesion is often unidentifiable intraoperatively. (11)

In conclusion, early diagnosis and intensive medical treatment prevent irreversible damage; therefore, sarcoidosis should be considered in the differential diagnosis of any idiopathic cranial neuropathies, especially in the presence of multiple lesions and bilateral involvement.


(1.) Gullapalli D, Phillips LH 2nd. Neurologic manifestations of sarcoidosis. Neurol Clin 2002;20(1):59-83, vi.

(2.) Nowak DA, Widenka DC. Neurosarcoidosis: A review of its intracranial manifestation. J Neurol 2001;248(5):363-72.

(3.) Mazziotti S, Gaeta M, Blandino A, et al. Perineural spread in a case of sinonasal sarcoidosis: Case report. AJNR Am J Neuroradiol 2001;22(6):1207-8.

(4.) Zajicek JP, Scolding NJ, Foster O, et al. Central nervous system sarcoidosis--diagnosis and management. QJM 1999;92(2):103-17.

(5.) Adcock BB. Facial numbness: A manifestation of sarcoidosis. J Am Board Faro Pract 1999;12(3):253-5.

(6.) Ahn JY, Kwon SO, Shin MS, et al. Chronic granulomatous neuritis in idiopathic trigeminal sensory neuropathy. J Neurosurg 2002;96(3):585-8.

(7.) Quinones-Hinojosa A, Chang EF, Khan SA, McDermott MW. Isolated trigeminal nerve sarcoid granuloma mimicking trigeminal schwannoma: Case report. Neurosurgery 2003;52(3):700-5; discussion 704-5.

(8.) Hobson-Webb LD, Donofrio PD. Inflammatory neuropathies: An update on evaluation and treatment. Curt Rheumatol Rep 2005;7 (5):348-55.

(9.) Vinas FC, Rengachary S. Diagnosis and management of neurosarcoidosis. J Clin Neurosci 2001;8(6):505-13.

(10.) Kidd D, Burton B, Plant GT, Graham EM. Chronic relapsing inflammatory optic neuropathy (CRION). Brain 2003;126(Pt 2): 276-84.

(11.) Dominguez J, Lobato RD, Madero S, et al. Surgical findings in idiopathic trigeminal neuropathy mimicking a trigeminal neurinoma. Acta Neurochir (Wien) 1999;141(3):269-72.

Ali Amin, MD; Jasminka L. Balderacchi, MD

From the Department of Pathology, Memorial Sloan-Kettering Cancer Center (Dr. Amin), and the Department of Pathology and Laboratory Medicine, St. Luke's-Roosevelt Hospital Center (Dr. Balderacchi), New York, N.Y.

Corresponding author: Ali Amin, MD, Memorial Sloan-Kettering Cancer Center, 1275 York Ave., New York, NY 10065. E-mail: almin33@
COPYRIGHT 2010 Vendome Group LLC
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2010 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Amin, Ali; Balderacchi, Jasminka L.
Publication:Ear, Nose and Throat Journal
Article Type:Case study
Geographic Code:1USA
Date:Jul 1, 2010
Previous Article:Positional dysphagia secondary to a Chiari I malformation.
Next Article:ENT Journal online.

Terms of use | Privacy policy | Copyright © 2018 Farlex, Inc. | Feedback | For webmasters