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Experimental model based on the C5 ventral root avulsion was used to evaluate the efficacy of brain-derived neurotrophic factor (BDNF) and Cerebrolysin treatment on motor neuron maintenance and survival resulted in the functional reinnervation of the nerve stump. In contrast to vehicle, BDNF treatment reduced the loss and atrophy of motor neurons and enhanced the regrowth axon sprouts into the distal stump of musculocutaneous nerve. However, the axon diameter of the myelinated fibers was smaller than those of control rats. The morphometric results were related to a low score in behavioral test similar to vehicle-treated rats. Cerebrolysin treatment greatly protected the motor neurons against cell death. Moreover, morphometric features of myelinated axons were better than those of rats treated with vehicle or BDNF. The mean score of grooming test suggested better results of the functional motor reinnervation than after BDNF administration. The majority of rescued motor neurons regenerating their axons through nerve graft in both BDNF- and Cerebrolysin-treated rats expressed choline acetyltransferase immunostaining. The results demonstrate that BDNF has more modest effects in preventing the death of motor neurons and functional recovery of injured motor nerve after root avulsion than Cerebrolysin.

The results of 13 patients with end-to-side anastomosis of the axillary nerve to various donor nerves were presented. The results were evaluated by means of functional and electrophysiological methods following avulsion and subsequent reconstruction of the brachial plexus. End-to-side anastomosis of the rat musculocutaneous nerve ( n =12), with the ulnar one, was used in the experimental model. The retrograde tracers were applied to prove the reinnervation. Fair and good results were achieved in neurotization of the axillary nerve in 75% of patients with follow-up longer than 24 months. Electrophysiology proved reinnervation in 100% of the patients. The average muscle strength, according to the muscle test, was 3.80. The functional recovery started within 7–12 months postoperatively. Retrograde staining in the experimental model demonstrated the reinnervation of the rat bicep muscles after 3 months from end-to-side anastomosis, mainly by collateral reinnervation from the ulnar nerve. The ulnar nerve motoneurons (70±13) were able to send off collateral sprouts from their intact axons into the musculocutaneous nerve. Other motoneurons of the same pool (21±4) regenerated axons directly into the musculocutaneous nerve without collateral sprouting, probably due to the axonotmesis of the motor fibers during the preparation of the perineurial window. Our results demonstrated that end-to-side anastomosis of the peripheral nerve might successfully be used for reinnervation procedures of a brachial plexus injury, mainly in cases with insufficient sources of motor nerve fibers from neighboring intact motor nerves.

Summary The acellular nerve graft was utilised to restore a functional reinnervation of the biceps brachii muscle from the motoneuron pool of the cervical spinal cord. The musculocutaneous nerve stump was sutured to an acellular nerve graft, the opposite end of which was inserted into the cervical spinal cord cranial to the avulsed C5 ventral root. The acellular nerve graft was repopulated by Schwann cells heavily immunostained for NGFr within 90 days. The Schwann cells migrating from the nerve stump reached the spinal cord grey matter, where they stimulated the motoneurons to send axonal sprouts. The functional reinnervation of the biceps brachii muscle was assessed by means of the behavioural (grooming) test and EMG, the presence of myelinated and unmyelinated axons was demonstrated by light and electron microscopy. The axonal reconnection of the musculocutaneous nerve stump was verified by horseradish peroxidase retrograde labelling of the spinal motoneurons. Moreover, the motoneurons on the operated side of the C5 spinal segment displayed increased immunostaining for GAP-43 in comparison to the contralateral side, whereas the pattern of AChE histochemical reaction was similar on both the operated and contralateral side, of the C5 segment 150 days after acellular graft implantation. The regenerated axons bridged a 4-cm long originally acellular nerve graft to reach and reinnervate the biceps brachii muscle. The reinnervation of the neuromuscular junctions was morphologically determined by immunofluorescence for neurofilaments. The number of myelinated axons in the acellular nerve graft was significantly higher than those growing over the cellular graft, but their diameter was smaller. The results of experiments presented here demonstrate functional recovery of the biceps muscle reinnervation through the acellular nerve graft repopulated by migrating Schwann cells. The process of reinnervation by acellular nerve graft is however delayed and worse in comparison with the cellular graft.

During an 8-month period, 86 consecutive infants and children under 2 years of age underwent palliative or corrective cardiac surgery, of whom 11 subsequently developed phrenic nerve injury (PNI). This was seen most frequently following classic or modified Blalock-Taussig shunts. The diagnosis was established by ultrasound screening of the diaphragm, and patients were initially managed expectantly with ventilatory support. In nine patients no further management was necessary with demonstrated return of diaphragmatic function. The remaining two patients underwent plication of the diaphragm. The mean time to diaphragmatic recovery was 40.8 days and was more prolonged in patients with paradoxical, as opposed to absent, diaphragmatic movement. There were no deaths in the series. A further retrospective review of 241 patients of similar age undergoing similar surgery over the preceding 2 years revealed evidence of PNI in 11 (4.6%). Recovery of diaphragmatic function was documented in all except one patient who died. Based on these results we believe that although PNI is associated with considerable morbidity, and frequently a long stay in Intensive Care, there is evidence of spontaneous recovery of diaphragmatic function in 90% of the patients. Consequently, plication of the diaphragm can usually be avoided. Ultrasound scanning is extremely useful in establishing the diagnosis and offers assistance in predicting prognosis and deciding management.

HYPOTHESIS: Regional cerebral blood flow (rCBF) and vascular reactivity strongly affect neuronal function. The restoration of blood flow values in the cerebral vascular system may be another benefit of carotid endarterectomy (CEA) in a specific group of patients. Animal experiments in dogs have provided evidence of neuronal reactivity depending on rCBF and vascular reactivity. However, as yet, there are no reports on neuronal reactivity changes related to altered perfusion parameters in humans. MATERIAL AND METHODS: The cohort under study consisted of 41 patients after transient ischaemic attack (TIA) or reversible ischaemic neurological deficit (RIND) whose neurological findings were normal (group A) and 17 patients after minor stroke with a mild degree of hemiparesis or hemihypesthesia (mRS≤2) (group B). All patients were examined 0-2 days before CEA, on postoperative days 3-7 and at 3 months after CEA. The tests included median nerve somatosensory evoked potentials (SEPs) and transcranial Doppler (TCD) at rest, during hypercapnia (et-CO 2 =7.0-7.5 kPa) and at rest after hypercapnia. RESULTS: Group A was found to have a significant increase in V sys , V mean and PI in response to hypercapnia in all periods (i.e., 0-2 days before CEA, on postoperative days 3-7 and at 3 months after CEA). N20/P25 amplitude decreased in response to hypercapnia before and early after CEA. Changes in other SEP parametres before and after hypercapnia were non-significant. Group B showed significant differences resulting from hypercapnia before and after CEA only in vasoreactivity (V sys , V mean , PI). CONCLUSION: In the analysed group of patients high-grade carotid stenosis caused no haemodynamic impairment. Moreover, no evidence was found of artificially increased rCBF being accompanied by an equally significant change in somatosensory evoked scalp response.

Experience with Intraoperative monitoring using neurophysiological and haemodynamic indices in 500 operations for carotid endarterectomy is reported.Transcranial Doppler technique (TCD), electroencephalogram (EEG) and bilateral median somatosensory evoked potentials (SEP) were performed. Latency and amplitude of SEP, spectral analysis of EEG signal and blood flow velocity in the medial cerebral artery (MCA) were continuously measured.After two consecutive drops of N20/P25 complex of more than 50%, a warning was given, and when the decrease continued, an the alarm raised. Abnormal EEG changes, if any, appeared after a significant decrease in the N20/P25 amplitude. A mean blood flow velocity drop below 40% of the reference value after cross clamping was rated as a significant warning event.A warning as a result of a decrease in N20/P25 amplitude occurred in 80 operations (16.0%), after an spectral edge frequency decrease in 2 cases (0.4%) and after a V(mean) decrease in 21 cases (4.2%). False negative results were experienced in 2 patients (0.4%). A shunt was inserted in 2.8% of the operations. The overall mortality/morbidity rate was 2.4%.A decrease of more than 50% in the amplitude of the thalamocortical somatosensory evoked potential complex N20/P25 proved to be the most reliable warning of danger of ischaemia during carotid endarterectomy.

Ventral root avulsion results in the loss of motoneurons in the corresponding spinal cord segment. In the present experiments we have tested effects of insulin-like growth factor-I (IGF-I) and Cerebrolysin on survival of avulsed motoneurons after their chronic intrathecal administration in the adult rats. We have found that avulsion of the C5 ventral roots results in significant loss of motoneurons in the same spinal cord segment due mainly to apoptosis. In comparison to the untreated control rats, the amount of motoneuron survival in avulsed ventral horn was significantly higher after 4 weeks intrathecal administration of IGF-I or Cerebrolysin. No significant differences were observed between effects of IGF-I and Cerebrolysin in our experimental model. The results suggest that both IGF-I and Cerebrolysin can reduce avulsion-induced loss of adult rat motoneurons.

The goal of cooperative project of the national registry of cardiovascular interventions is analysis of quality of cardiovascular care with risk stratification and assessment of clinical indicators at organizational and individual level. Bayes methodology of stratification and risk prediction is used.

Specialised form of database named DataCube for assessment of quality, outcomes and costs of the healthcare in cardiac surgery was built at the Institute of Clinical and Experimental Medicine (IKEM). Risk stratification of patients was done using Bayes predictive model. Such prediction well correlated with calculated costs. The results achieved promise the system to become an important decision making tool, which may improve identification of high risk patients.

The authors use as a basis experience with a group of 389 patients operated in 1989-1997 on account of degenerative diseases of the cervical spine with neurological manifestations. The results are compared with experience assembled in 1998-1999. In the new group (188 patients with the same diagnosis) the same indication criteria were used but in case of myelopathy associated with multisegmetal cervical stenosis not only multilevel discectomy was performed (as in the previous group) but in addition also 1-3 segmental corpectomy (somatectomy). The results were evaluated separately for both methods used. The authors emphasize the necessity of a radical approach during decompression of neurological structures incl. removal of uncovertebral osteophytes which must be combined with suitable stabilization of the fusions or possibly be supported by instrumentation. In the discussion the authors illustrate in the form of a review the development of anterior cervical corpectomy as one of the methods of an anterior approach to the cervical spine used at first in traumatic and oncological conditions, later extended to operations on account of degenerative, dysplastic conditions and other diseases. The authors wish to help to define criteria for application of corpectomy when treating stenoses of the spinal canal in the cervical region. The indication will be defined in a perspectively followed up group where a detailed clinical and electrophysiological algorithm for examination was submitted as well as postoperative follow-up and processing of the resulting data.

Publisher Summary This chapter evaluates evoked potential (EP) changes and intra-individual correlation with clinical changes to determine the value of EPs in the assessment of the results of therapy and the value of EP findings in the prediction of clinical outcome in spondylotic cervical myelopathy (SCM). There is insufficient evidence documenting the value of somatosensory evoked potential (SEP) and motor evoked potentials (MEPs) in the evaluation and prediction of the treatment results of SCM patients. In the project comparing surgery versus conservative treatment in patients with spondylotic cervical myelopathy, three points are followed: if SEPs and MEPs are useful in the evaluation and prediction of the effect of therapy; weather SEPs and MEPs useful in the evaluation and prediction of the clinical course in subclinical cervical spine compression; and if its surgery in patients with mild and moderate forms of SCM superior to the conservative treatment. However, studies show, on average, there is no clinically substantial differences in outcome of patients suffering from mild and moderate forms of SCM treated either conservatively or surgically over a period of two years.

Study design. A two-year follow-up prospective randomised electrophysiological and clinical study was performed in patients with spondylotic cervical myelopathy. Objective. To assess the value of somatosensory (SEP) and motor evoked potentials (MEP) in the evaluation and prediction of the effect of therapy. Summary of background data. Previous studies have yielded conflicting data concerning the correlation between the changes in evoked potential parameters and the clinical post-surgical outcome in spondylotic cervical myelopathy (SCM). Methods. Sixty-one patients with magnetic resonance imaging (MRI) signs of spondylotic cervical cord compression and clinical signs of cervical myelopathy were divided into two groups according to the degree of clinical cervical cord involvement. Forty-nine patients with mild and moderate SCM were randomised into groups that underwent either surgical or conservative therapy. Patients were evaluated clinically and by the means of SEP and MEP. Results. 1. The clinical and evoked potential (EP) changes showed good correlation as a group, but poor correlation intra-individually. 2. There were no significant EP and clinical group changes after 6 months and 2 years in mild myelopathy group treated either surgically and conservatively, while patients with severe myelopathy displayed significant improvement in both clinical and EP parameters after surgery. 3. In a subgroup of patients the isolated segmental medullar N 13 abnormality predicted favourable post-surgical clinical outcome. Conclusions. Longitudinal EPs showed limited utility in the evaluation of the results of therapy in an individual patient. They could be useful in the group assessment of the results of therapy and in labelling a subgroup of patients with potentially favourable post-surgical outcome.

A seven-year-old girl with persistent ductus arteriosus developed acute bacterial endocarditis with large vegetations in the ductus and the left pulmonary artery. Conservative management was not successful: repeated embolisation to the lungs necessitated operation during the acute endocarditis. Details of the operative technique are presented and discussed.

Thirty five patients with brachial plexus injury have been operated on. Results were very good in the case of supraganglionic lesions in 15 patients. Fair and good results were obtained in 72% of Is patients with neurotization procedure of musculocutaneous and axillary nerves. Transfer of latissimus dorsi muscle instead of the biceps muscle was successful in another two cases. In the experimental animals the reinnervation of the biceps muscles was obtained by application of both cellular and acellular nerve grafts into the spinal cord and distally sutured with musculocutaneous nerve stump. Behavioural, electrophysiological as well as morphological methods proved the reconnection of the spinal motor neurons with the muscle end plates.

107 patients suffering from axial dyskinesias (torticollis and torsion dystonia) were observed at our clinic over a period of 10 years. In 15 patients, stereotactic lesions involving the head-turning bundle at the caudatocapsular level, which mediates forced adversive movements, were performed. In 70% good to excellent results were confirmed. However, differences between forced adversive movements and torticollis were identified. There are striking motor and motivational similarities between torticollis and ritualized fixed action patterns of low-ranking subjects. The aetiology of axial dyskinesias, especially of torticollis, is multifactorial, long-term psychic stress being an important factor. The relationship of axial dyskinesias, especially of torticollis, to compulsive neuroses is discussed, and Mazar's 'adversive' target area is identified as a partial or-bitomedial leukotomy.

Treatment with general anesthesia (neuroleptanalgesia) and deep hypothermia was performed on 8 patients suffering from epilepsy. The body temperature was decreased to 29 °C and the temperature in the brain ventricles to 16 °C. Somatosensory evoked potentials were recorded. Increase in latency of all waves was observed, and it was noted that the more distant the wave, the higher the increase in latency. Statistical values are given for N1, N2 and N3. A parallel decrease in the amplitudes of all components of the somatosensory evoked potential was also present.

The inhibitory effects of uncouplers on amino acid transport into three marine bacteria, Vibrio alginolyticus 118, Vibrio parahaemolyticus 113, and Alteromonas haloplanktis 214, into a moderate halophile, Vibrio costicola NRC 37001, and into Escherichia coli K-12 were found to vary depending upon the uncoupler tested, its concentration, and the pH. Higher concentrations of all of the uncouplers were required to inhibit transport at pH 8.5 than at pH 7.0. The protonophore carbonyl cyanide m-chlorophenylhydrazone showed the greatest reduction in inhibitory capacity as the pH was increased, carbonyl cyanide p-trifluoromethoxyphenylhydrazone showed less reduction, and 3,3',4',5-tetrachlorosalicylanilide was almost as effective as an inhibitor of amino acid transport at pH 8.5 as at pH 7.0 for all of the organisms except A. haloplanktis 214. Differences between the protonophores in their relative activities at pHs 7.0 and 8.5 were attributed to differences in their pK values. 3,3',4',5-Tetrachlorosalicylanilide, carbonyl cyanide m-chlorophenylhydrazone, 2-heptyl-4-hydroxyquinoline-N-oxide, and NaCN all inhibited Na+ extrusion from Na+-loaded cells of V. alginolyticus 118 at pH 8.5. The results support the conclusion that Na+ extrusion from this organism at pH 8.5 occurs as a result of Na+/H+ antiport activity. Data are presented indicating the presence in V. alginolyticus 118 of an NADH oxidase which is stimulated by Na+ at pH 8.5.

Tests of postural rotational laterality were carried out in 63 patients suffering from torticollis (53) or torsion dystonia with torticollis (10) and in 33 normal subjects. There was a correlation between the predominant direction of postural functions and the direction of the rotatory component of torticollis. Torticollis and torsion dystonia may be due to the release of a postural rotational laterality in pre-disposed subjects and not to a presumed asymmetric lesion of the brain-stem.

In 40 adult patients stabilized on the tilt table, no evidence was found that the amount of activity at rest in spastic muscles depends on the position of the head in space. The influence of postural labyrinthine reflexes (Magnus) was not confirmed. The activity in spastic extensor muscles was significantly higher (t greater than 1%) in the prone position. The activity in spastic flexor muscles was higher (t greater than 1%) in the supine position. Extralabyrinthine forces (tonic stretch reflexes and exteroceptive reflexes) are assumed to be decisive in these changes. In the same group of patients, the symmetric deep neck reflexes were examined. The patient actively flexed his head forwards or backwards. Significant increase in the activity at rest in spastic extensor muscles on dorsal flexion of the head in the prone position was found (t greater than 1%). Significant increase in the activity at rest in spastic flexor muscles on ventral flexion of the head in the supine position was also found (t greater than 5%). The phenomena of irradiation are assumed to be decisive in these changes. In another group of 27 adults the asymmetric deep neck reflexes (Magnus and De Kleijn) were examined. The patient actively turned his head either to the left or to the right, while his arms were raised (Hoff-Schilder maneuver). When the degree of rotation of the head was slight, the trunk and arms deviated in the same direction. When the rotation of the head was extreme, and reached behind the shoulder, the trunk and arms often reversed the direction of deviation. The effect of asymmetric deep neck reflexes was not confirmed. Visual perception and the mechanism of focusing are assumed to be decisive in these changes. The head turns toward the object of interest in the visual field by the mechanism of eye-centering (Bender) and influences the position of the trunk and motor patterns of the upper extremities (motor principle "eyes-hand").

50 patients with complete interruption of the N. radialis, N. ulnaris or N. medianus who had been treated surgically in the classic manner, i.e. with a suture on the epineurium, were subjected to clinical and electromyographical checkups within 3 to 10 years after the operations. The results of the examinations were correlated with specific indicators of the lesion and the operation. The most important and statistically significant correlation was confirmed to exist between the injury/operation interval and the extension of the nerve defect, with the extension of the defect being more significant. Depending on the extension of the defect, the following critical time intervals were found: with a defect of 2.5 cm 24 months, with a defect of 3 cm 18 months, with a defect of 4 cm 9 months and with a defect of 5 cm 6 months. If the defect was longer than 5 cm or the time interval longer than 24 months, the final result had to be assessed as bad in all cases.