CHAPTER 11

Sarcoidosis is an inflammatory multisystemic disorder. Its cause is not known. The disease may involve any part of the nervous system. The incidence of clinical involvement of the nervous system in a sarcoidosis population is estimated to be y5–15 % [1, 2]. However, the incidence of subclinical neurosarcoidosis may be much higher [3, 4]. Necropsy studies suggest that ante mortem diagnosis is made in only 50 % of patients with nervous system involvement [5]. As neurosarcoidosis may manifest itself in many different ways, diagnosis may be complicated [2, 3, 6–10]. It may appear in an acute explosive fashion or as a slow chronic illness. Furthermore, any part of the nervous system can be attacked by sarcoidosis, but the cranial nerves, hypothalamus and pituitary gland are more commonly involved [1]. Sarcoid granulomas can affect the meninges, parenchyma of the brain, hypothalamus, brainstem, subependymal layer of the ventricular system, choroid plexuses and peripheral nerves, and also the blood vessels supplying the nervous structures [11, 12]. One-third of neurosarcoidosis patients show multiple neurological lesions. If neurological syndromes develop in a patient with biopsy-proven active systemic sarcoidosis, the diagnosis is usually easy. However, withou