Clinical Neuroscience

[The significance of high-resolution ultrasonography in the diagnosis of peripheral nerve disorders]


JANUARY 25, 2013

Clinical Neuroscience - 2013;66(01-02)

[High resolution ultrasonography is an emerging technique for the investigation of peripheral nerves and is increasingly used worldwide in the diagnosis of peripheral nerve disorders, however, until now it is not widespread in Hungary. According to the literature this method is especially useful in entrapment neuropathies, traumatic peripheral nerve injuries, tumors of the peripheral nerves and sonographically guided interventions. Ultrasonography allows precise morphological analysis and quantitative measurements of the nerves providing useful complementary information to electrodiagnostic data. In entrapment neuropathies ultrasound shows nerve swelling mainly proximal to the sites of compression and a focal change of echotexture. On longitudinal scan, an abrupt caliber change and spindle-like swelling of the compressed nerve segment can be seen. Evaluation of the anatomical background and visualisation of the postoperative and posttraumatic changes provide useful information for planning of the therapy. Ultrasound may be of significant help in localizing the pathological nerve segment when it is at an electrophysiologically inaccessible site or when substantial secondary axonal loss precludes precise electrophysiological localization and it might even show pathological changes when nerve conduction studies are normal. Contrary to electrophysiological investigation ultrasonography might discover neurotmesis in the akute phase of traumatic nerve injuries indicating the necessity of surgical intervention. We provide a summary of the main indications and further application areas of this method.]



Further articles in this publication

Clinical Neuroscience

[Editorial message]

KINCSES Zsigmond Tamás

Clinical Neuroscience

[Aspirin and clopidogrel resistance: possible mechanisms and clinical relevance. Part II: Potential causes and laboratory tests]

VADÁSZ Dávid, SZTRIHA K. László, SAS Katalin, VÉCSEI László

[Recent meta-analyses have indicated that patients with vascular disease demonstrated by laboratory tests to be aspirin or clopidogrel-resistant are at an increased risk of major vascular events. The suggested mechanisms of aspirin resistance include genetic polymorphism, alternative pathways of platelet activation, aspirin-insensitive thromboxane biosynthesis, drug interactions, or a low aspirin dose. Clopidogrel resistance is likely to develop as a result of a decreased bioavailability of the active metabolite, due to genetic variation or concomitant drug treatment. Additional work is required to improve and validate laboratory tests of platelet function, so that they may become useful tools for selection of the most appropriate antiplatelet therapy for an individual patient. Improvements in antiplatelet treatment strategies in the future should lead to a reduction in premature vascular events.]

Clinical Neuroscience

[Blood lipid peroxidation, antioxidant enzyme activities and hemorheological changes in autistic children]

LÁSZLÓ Aranka, NOVÁK Zoltán, SZÕLLÕSI-VARGA Ilona, HAI Quai Du, VETRÓ Ágnes, KOVÁCS Attila

[Objectives - Early infantile autism is a severe form of childhood psychiatric disease with characteristic symptoms. Hyperserotoninaemia in 43.5%, lactic acidosis 43% and hyperpyruvataemia in 30% were biochemically demonstrated in autistic children. Our earlier results led to the postulation that a disequilibrium in the blood redox is involved in infantile autism; the oxidative loading and the antioxidant defending enzyme system were investigated together with the hemorheological parameters in infantile autism. Methods - Malonyl-dialdehyde (MDA) endproduct of lipid peroxidation and activities of the antioxidant enzymes: superoxide dismutase (SOD), catalase (C-ase), glutathione peroxidase (GP-ase) and reduced glutathione (GSH) were biochemically determined from plasma and red blood cells. Patients - The antioxidant specificities were investigated in plasma and red blood cell haemolysate from 25 infantile autistic children. Results - Significantly increased superoxide dismutase (SOD) (2.89 vs. 1.32 U/mg protein, p<0.01) and decreased glutathione peroxidase (0.620 vs. 0.910 U/mg protein, p<0.01) levels as well as catalase (0.463 vs. 4.948 BU/mg protein, p<0.001) activities were detected; while the plasma and erythrocyte lipid peroxidation and the reduced glutathione (GSH) levels did not change. The results of the investigated prooxidant and the antioxidant status provide evidence that there exists an oxidative stress in children with infantile autism. While investigating the hemorheological parameters of 25 infantile autistic patients, some characteristic pathological parameters were detected: the initial filtration rate (Fi) (0.72 vs. 0.75 p<0,01) and the clogging rate (CR) (1.926 vs. 2.912, p<0.01) values of red blood cells (RBC) decreased while the mean transit time (Tc) (8.93 vs. 7.39, p<0.001) increased suggesting reduced RBC deformability.]

Clinical Neuroscience

[Experiences with a self developed accelerometer]


[Objective - In neurology the objective evaluation of improvement of paresis on every-day practice. The aim of this study was to develope and test a small 3-d acceleration measuring device and validate its usefulness. Patients and methods - We collected data from 17 mild and medium severity hemiparetic, bedridden acute ischaemic and hemorrhagic stroke patients and compared with data of 22 control subjects. The devices were attached to the paretic and non-paretic extremities and any movements (m/s2) and movement-durations were registered (24h). The data of movement-monitors were compared also with the changes of National Institute of Health Stroke Scale and European Stroke Scale. The electromiograph-sensor of polysomnograph has been used for validation. Results - Mild differences could be found in the use of dominant and non-dominant upper extremities of control persons. The control persons used their upper extremities more frequently than the stroke patients. Our data showed significant correlation with National Institute of Health Stroke Scale. Higher values on the scores were accompanied with less intensive use of extremities. We found a correlation between the consiousness level of patients and their activity of upper extremities. If the patients had severe consiousness disturbances they used significantly less their upper extremities. Conclusion - Our device sensitively detected the movement-differences between paretic and non-paretic extremities and can be used for quantitative evaluation of patient's neurological and consciousness status.]

Clinical Neuroscience

[Intact short-term memory and impaired executive functions in obsessive compulsive disorder]

DEMETER Gyula, RACSMÁNY Mihály, CSIGÓ Katalin, HARSÁNYI András, NÉMETH Attila, DÖME László

[Background and purpose - Previous neuropsychological studies produced inconsistent results with tasks tapping short-term verbal and visual-spatial memory and executive functions in obsessive compulsive disorder (OCD). The aim of this study was to investigate the presence of deficits in these cognitive domains. A further goal was to describe the distribution of patients in different impairment ranges for all functions, and clarify the relationship between symptom severity and cognitive impairments. Methods - Thirty patients with OCD (DSM-IV) and 30 healthy volunteers were compared using well-known neuropsychological tasks. We assessed short-term verbal memory with the Digit Span Forward and Digit Span Backward Tasks, short-term visual-spatial memory with the Corsi Block Tapping Task, while we measured the level of executive functions with the StroopTask and the Wisconsin Card Sorting Test (WCST). Results - Compared with a matched healthy control group, the performance of OCD patients was in the impaired range only in the two executive tasks. We find a significant positive correlations between the Y-BOCS (Yale-Brown Obsessive Compulsive Scale) total scores and the number of perseverative responses (r(28)=0.409, p<0.05) and perseverative errors (r(28)=0.385, p<0.05) in the WCST. Conclusion - Our results gave evidence that executive functions are impaired while short-term memory is intact in OCD. This is in line with neuropsychological model of OCD that the deficit of cognitive and behavioral inhibition are responsible for the main cognitive findings of this disorder, most prevalently the deficit in set shifting and prepotent response inhibition.]

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Clinical Neuroscience

[Intraoperativ electrophysiological monitoring during neurosurgery on eloquent structures]

FEKETE Gábor, NOVÁK László, ERÕSS Loránd, FABÓ Dániel, BOGNÁR László

[Objective - We summarize our experiences on intraoperative electrophysiological monitoring during neurosurgical procedures on eloquent neuronal structures. Patients, methods - Sixty patients were enrolled retrospectively in our study with pathologies involving eloquent neuronal structures. They were operated between May 2011. and March 2012. at the University of Debrecen, Department of Neurosurgery and at the National Institute of Neurosciences. Patients underwent standard preoperative examinations due to the primary pathology. In all cases we used intraoperative electrophysiological monitoring. We had 22 cases with cranial nerve monitoring, 10 cases with cauda monitoring, 16 cases with motor system monitoring, six cases with complex spinal cord monitoring, three degenerative spine reconstructions and 3 awake surgeries. Results - We found that with the use of intraoperative electrophysiology we could make these neurosurgical procedures safer, and were able to optimize the extent of resection in the cases of oncological pathologies. Conclusions - Our experiences as well as the international literature suggests that in certain high risk neurosurgical procedures intraoperative electrophysiology is indispensible for safe and optimally extended operation.]

Clinical Neuroscience



[Introduction - While it is several decades ago that electrophysiological studies in the early stages after an ischaemic stroke revealed spontaneous activity in the affected muscles, today few data are available on the peripheral changes in later stages after a cerebrovascular event. The aim of this study was to detect electrophysiological signs that could indicate changes at the motor unit level occurring within a longer post-stroke period. Patients and methods - Forty-four patients who had developed hemiparesis after an ischaemic stroke in the area of the middle cerebral artery were involved in the study. Motor and sensory nerve conduction studies and electromyography were carried out on each side on six nerves and in five muscles respectively. Values between the affected and unaffected side were compared by statistical methods. Results - In patients with hemiparesis present for less then nine months, low M wave amplitudes, fibrillation potentials and an increased number of complex motor unit potentials were found on the affected side; in patients with symptoms present for more then nine months the mean duration and size index of the motor unit potentials in the paretic abductor digiti minimi muscle were increased. These data suggest a process of neurogenic type. The signs of distal axonal damage observed in the early period after stroke have been replaced later by chronic neurogenic changes. These changes could be the consequence of spinal motor neuron damage and axonal transport disturbance due to the loss of supraspinal trophic inputs. Conclusion - The correlation between the extent of electrophysiological changes and of the central motor deficit of the patient indicates the importance of delaying this process by appropriate rehabilitation procedures.]

Clinical Neuroscience

[Selective dorsal rhizotomy in the treatment of spasticity - Hungarian experiences ]

FEKETE Gábor, NOVÁK László, VEKERDY-NAGY Zsuzsanna, BOGNÁR László

[Objective - We summarize our initial experiences with selective dorsal rhizotomy that we introduced in Hungary to manage the spasticity of patients with cerebral palsy. Patients and methods - Thirty spastic patients were enrolled in our study. All of the patients were operated between July 2014 and June 2015. We performed selective dorsal rhizotomy from a single-level approach at the level of conus medullaris in all cases, with electrophysiological control. Results - We could perform the surgery in all cases safely. Adverse events related either to damage of neurological structures, or to surgery did not occur. The planned rehabilitation courses before and after the operations are in progress in all cases. Conclusion - Selective dorsal rhizotomy is an irreversible surgical intervention to treat spasticity. With sufficient experience and electrophysiological control it can be performed safely, and the early results are promising. ]

Clinical Neuroscience

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Clinical Neuroscience

[Thallium poisoning induced polyneuropathy - clinical and electrophysiological data]


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