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Ocular color-coded duplex sonography (OCCS), when performed within the safety limits of diagnostic ultrasonography, is an easy noninvasive technique with high potential for diagnosis and therapy in diseases with raised intracranial pressure and vascular diseases affecting the eye. Despite the capabilities of modern ultrasound systems and its scientific validation, OCCS has not gained widespread use in neurological practice. In this review, the authors describe the technique and main parameter settings of OCCS systems to reduce potential risks as thermal or cavitational effects for sensitive orbital structures. Applications of OCCS are the determination of intracranial pressure in emergency medicine, and follow-up evaluations of idiopathic intracranial hypertension and ventricular shunting by measuring the optic nerve sheath diameter. A diameter of 5.7 - 6.0 mm corresponds well with symptomatically increased intracranial pressure (> 20 cmH2O). OCCS also helps to discriminate between different etiologies of central retinal artery occlusion - by visualization of a "spot sign" and Doppler flow analysis of the central retinal artery - and aids the differential diagnosis of papilledema. At the end perspectives are illustrated that combine established ultrasound methods such as transcranial color-coded sonography with OCCS., (© Georg Thieme Verlag KG Stuttgart · New York.)

Tick borne encephalitis (TBE) is an important viral encephalitis in central and eastern Europe. Cerebrospinal fluid (CSF) pleocytosis has been described in all published patients so far. This may be due to selection bias, however, as CSF pleocytosis is often used as a case definition parameter. The frequency of TBE without CSF pleocytosis is unknown. We report two cases who developed severe TBE without CSF pleocytosis. A normal CSF cell count should therefore not discourage from the differential diagnosis of TBE and deter from serological testing in patients with a clinical constellation suggesting TBE.

Meningeal melanocytoma refers to the uncommon clinical appearance of a generally benign tumour deriving from leptomeningeal melanocytes. Meningeal spread of this tumour is very rarely observed. We present the case of a 38-year-old man with meningeal melanocytoma of the cerebello-pontine angle, who showed a biphasic course of this disease, with a stable period followed by a steady progress within few months. After surgical resection of the melancytoma in the left skull base and of a first local recurrence five years later, a second local recurrence occurred 6 years after diagnosis, with intracerebral and spinal meningeal seeding. This tumor did not respond to a combined radiochemotherapy including oral temozolomide, and the patient died 5 months after starting treatment for this relapse. Secondary malignisation of the melancytoma is suggested.

A 63-year-old female was admitted to the hospital with leg and forearm paresthesias. We found progressive ataxia, dementia, and psychosocial deterioration. The clinical symptoms, the neurologic and psychiatric abnormalities together with the inflammatory cerebrospinal fluid alteration and the cerebral magnetic resonance imaging changes suggested a paraneoplastic etiology. It was confirmed by paraneoplastic antineuronal antibodies in the patient's serum and the histological diagnosis of a small cell bronchial carcinoma. The prognosis of patients with paraneoplastic symptoms is the better the earlier a diagnosis is established and antitumor therapy is initiated.

Introduction: A prospective, randomized and controlled trial is conducted to compare carotid endarterectomy and carotid stenting in high grade symptomatic carotid artery stenoses., Methods: According to the study design symptomatic patients with a angiographically high-grade (> or = 70%) internal carotid artery stenosis are included. Pre- and postinterventional diagnostics during the hospitalization period includes neurological assessment, duplex sonography of the cervical and cerebral arteries and magnetic resonance imaging of the brain. Follow-up examinations are scheduled after 1, 6 and 12 months and consist of a neurological assessment and duplex sonography. After 12 months selective angiography and magnetic resonance imaging of the brain will be performed additionally. During a period of 9 months up to now 23/137 patients treated for a carotid artery stenosis were included in the study, 11 patients underwent surgery and 12 patients carotid stenting., Results: Carotid stenting and endarterectomy was primarily successful without residual stenosis > 30% in each patient without the occurrence of stroke or death. In 18 follow-up examinations (neurological assessment including duplex sonography) of 13 patients (13 follow-up examinations after 30 days, 5 after 6 months) no relevant restenosis and no stroke occurred., Conclusion: As of yet, carotid stenting was a safe procedure. Due to the small number of patients a definitive conclusion can not be drawn.

Echo-enhancing agents improve the signal intensity of transcranial Doppler signals, enabling a novel approach of three-dimensional transcranial vascular imaging by Doppler ultrasound. The basic principle, system requirements and early clinical results with a custom built system are described. Transcranial color Doppler imaging was performed through the temporal bone acoustic window. During i.v. administration of the transpulmonary stable, galactose-based echo-enhancer Levovist (Schering) the video output of the ultrasound scanner was digitized and the spatial position of the recorded frames was simultaneously registered using a mechanical position sensor. After automatic segmentation of the color information, the 3D datasets were reconstructed offline using a Unix-based workstation (Silicon Graphics). Visualization was achieved by maximum intensity projection or surface visualization techniques. Administration of Levovist resulted in good enhancement of the vascular Doppler signal intensity, enabling acquisition of a 3D dataset of the complete circle of Willis with an imaging window of approximately 3-5 min for one i.v. injection. The vascularity of tumors could be recorded as a 3D dataset and further analyzed. The power Doppler technique with echoenhancement proved a valuable tool for 3D dataset recording. 3D datasets clearly facilitated the diagnosis of the vascular anatomy and lesion vascularity and provided additional information on localization of feeders, vascular displacement and extent of tumor vascularity.

Transcranial color-coded real-time sonography (TCCS) combines transcranial Doppler sonography and color-coded B-mode scanning of the brain parenchyma and cerebral vessels. This technique is not invasive and a broad spectrum of intracerebral lesions such as vascular lesions (ischemic stroke and intracerebral hemorrhage, aneurysms, arteriovenous malformations, arteriosclerotic vascular degeneration) and parenchymal lesions (brain tumors, degenerative and neuropsychiatric disorders) can be disclosed. Compared with MRI and CT, the ultrasound system is movable. Thus, it can be used easily in emergency rooms and intensive care units. In addition, TCCS can disclose new insights into the pathophysiology of disorders of the CNS, as in neuropsychiatric diseases. Ultrasound contrast agents improve the depiction of intracranial vessels. The pathology of the venous system can be identified.

We examined three groups of adult patients to evaluate the clinical application of transcranial colour-coded real-time sonography (TCCS): 28 patients suffering from intracerebral haemorrhage, 36 patients with subarachnoid haemorrhage and 38 patients with primary brain tumours. All sonographic examinations were performed through the intact skull. Cerebral haemorrhages were visualised via TCCS as hyperechogenic areas, which were closely correlated in size and location to CT findings. Apart from the imaging of subarachnoid haemorrhages and cerebral vasospasms, TCCS permitted the identification of the angiographically confirmed aneurysms in 76%. Brain tumours were delineated in the vast majority of the patients examined. In this type of pathology TCCS provided additional information on tumour extension and macroscopic appearance.

Transcranial colour-coded real time sonography (TCCS) is a new, non-invasive diagnostic bedside procedure allowing two-dimensional imaging of cerebral parenchymatous structures and large intracranial arteries through the intact skull. So far we examined a population of 183 patients und 53 normal subjects, all above 18 years of age. 24 (10%) subjects were not suitable for examination. Two-dimensional imaging of telencephalic, diencephalic, mesencephalic and pontine structures is feasible. Intravascular blood flow phenomena may be analysed quantitatively by an integrated pulsed wave Doppler system. The diagnosis of arterial stenosis and occlusion could be established in 14 patients each by analysing the colour-coded B-mode image and Doppler frequency spectrum. TCCS may complement diagnostic tools in neurology and may improve standardisation of transcranial Doppler measurements.

In standard concentric needle electromyography the typical triphasic potential of a motor unit (MUP) consists of the spike component and the positive initial and terminal parts. Whereas the main spike is generated by a few muscle fibers located close to the tip of an electrode, the initial and terminal parts represent the sum of activities of a large proportion of fibers within the motor unit. The size of the initial and terminal part is assessed by measuring the duration of the MUP. In addition to the duration we calculated the mean absolute voltage outside the spike component: The signal was digitized and several individual MUPs of the same motor unit were averaged. The point of maximal negative rise was identified. Then the mean absolute voltage between -5 ms and +5 ms around this point, excluding the interval from -1 ms to +1 ms, was calculated. This parameter is exactly defined and unambiguous. The biceps brachii muscles of 30 healthy volunteers were examined in order to establish normal values. In 24 patients suffering from various myopathies 18 had significant (p less than 0.01) reduced initial and terminal parts, whereas only 13 patients showed decreased potential duration (according to Buchthal 1957).