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A commonly experienced effect of cold is a sensation of numbness and loss of sensibility in the fingers. Intact tactile sensibility of the grasping digits is essential for the efficient scaling of grip force level during the manipulation of hand-held objects. We investigated whether or not cooling of the grasping digits affects scaling of the grip force magnitude in relation to the loads resulting from continuous vertical arm movements performed with a grasped instrumented object. Maxima and minima of load force occurred at the lower and upper turning point of the movement cycle, respectively, and were accompanied by maximum and minimum peaks in grip force occurring close in time prior to and following digit cooling, respectively. Thus, digit cooling did not influence the ability to adjust the grip force profile in anticipation of movement-induced fluctuations in load force. However, subjects established significantly higher grip forces against the hand-held object following digit cooling and generated a 10-70% higher ratio between grip and load forces at the upper and lower turning points of the movement cycle. It is thought that the impaired economical scaling of grip force level is the result of reduced sensory feedback from the grasping fingers during digit cooling. The results provide further evidence to support the suggestion that cutaneous afferent input plays a subordinate role in the predictive temporal regulation of the grip force profile, but is used to adapt economically the force level to the actual loading requirements during dynamic object manipulation.

Capillary haemangioma is a benign tumour frequently encountered in the skin and other soft tissues. Histologically, these vascular lesions are characterised by nodules of capillary-sized vessels lined by flattened endothelium, each of which is subserved by a feeding vessel. Capillary haemangioma of the central and peripheral nervous system is extremely rare. Less than 20 of these lesions have been described as occurring within the confines of the spinal dura mater, in close relation to the conus medullaris and nerve roots of the cauda equina. The presenting symptoms are similar to those of more common intradural tumours at the conus-cauda region. Magnetic resonance imaging is the imaging modality of choice, and homogeneous enhancement following administration of Gd-DTPA is a useful clue to the diagnosis. Complete resection is the treatment of choice, and during surgery the vascular tumour is usually found encapsulated and sharply bordered from the surrounding parenchyma of the spinal cord and affected nerve roots. In the present account we give an overview of the clinical features, neuroradiological findings, therapeutic options and histopathological differential diagnostic aspects of spinal intradural capillary haemangioma. In general, vascular lesions of this entity are preoperatively misdiagnosed as neoplasms, and a higher level of clinical and radiological suspicion may avoid surgical overtreatment of these benign tumours.

Sarcoidosis is a multisystem disease of unknown cause and with a worldwide distribution. Involvement of the central nervous system occurs in a relatively small number of patients with sarcoidosis. Isolated neurosarcoidosis without signs of systemic disease is a rarity. Because of its non-specific clinical presentation and neuroradiological imaging characteristics, intracranial neurosarcoidosis remains a very difficult diagnosis, particularly in the absence of systemic signs of the disease. Intracranial neurosarcoidosis has a predilection for the basal leptomeninges commonly affecting the cranial nerves, but any part of the brain may be involved, resulting in a wide spectrum of clinical syndromes. Cranial nerve involvement is the most common single symptom. Intracranial sarcoid manifests as nodular or diffuse leptomeningeal thickening and extraor intra-axial parenchymatous lesions. Intracranial sarcoid may mimic various forms of meningitis, including carcinomatous and intracranial mass lesions such as meningioma, lymphoma and glioma, based on neuroradiological imaging. Magnetic resonance imaging is a very sensitive diagnostic tool for detecting intracranial abnormalities due to neurosarcoidosis. Lumbar puncture is useful in ruling out other neurological disorders, in particular infectious, but cerebrospinal fluid findings are not specific. Angiotensin-converting enzyme in serum and cerebrospinal fluid may be increased, decreased or normal. Therapy consists of immunosuppressive agents and should be initiated with corticosteroids. Other immunosuppressive drugs should be added in severe cases or after frequent recurrences. We review here all aspects of intracranial neurosarcoidosis from the clinical point of view, with special emphasis on presentation, diagnostic procedures, differential diagnostic considerations and treatment.