Transient and long-term feeding by means of percutaneous endoscopic gastrostomy in neurological rehabilitation.

In 28 patients of a neurological rehabilitation unit of a hospital the use of enteral nutrition via percutaneous endoscopic gastrostomy (PEG) tubes was reviewed. During a total observation period of 5,172 days no life-threatening complications occurred. Minor complications were observed in 12 patients (43%) in the first 2 weeks after the insertion and in 5 patients (18%) afterwards. The nutritional status stabilized in all subjects. Transient PEG feeding was performed in 11 patients (39%) with a mean duration of 150 days. We conclude that hesitation in the application of PEG feeding in neurological rehabilitation should be abandoned. The timing and monitoring of PEG feeding in patients undergoing neurological rehabilitation for acute remitting neurological disorders is discussed.

Neurological monitoring of neurotoxicity induced by paclitaxel/cisplatin chemotherapy.

To evaluate the neurotoxicity of paclitaxel/cisplatin chemotherapy, we studied neurological and electrophysiological functions in 14 patients who had been treated with 1-7 courses of paclitaxel/cisplatin. The cumulative paclitaxel and cisplatin doses ranged from 175 to 1225 mg/m2 and 100-700 mg/m2, respectively. Neurological examinations as well as motor nerve conduction studies of the peroneal nerve were performed and summarised by means of a peripheral neuropathy score. Neurotoxicity with onset usually after the second treatment cycle occurred in 13 patients. 12 patients complained about sensory symptoms, 13 patients had impaired vibration sense and 8 patients developed additional muscle weakness, predominantly of the legs. Dysfunction of peroneal motor nerve conduction occurred in 13 patients. Reduction of amplitudes as well as slowing of conduction velocities were seen in 13 patients and prolonged distal latencies in 10 patients. The peripheral neuropathy score was elevated in 13 patients. Neurological symptoms, impairment of both vibration sense and tendon reflexes, and the peripheral neuropathy score increased with the cumulative doses of paclitaxel/cisplatin. Serial analysis among selected patients also revealed an increase in neurotoxicity with increasing cumulative drug doses. These data indicate the development of neurotoxicity in most patients treated with paclitaxel/cisplatin and also suggest that early signs of neurotoxicity can be detected by clinical examination with emphasis on symptoms as well as vibration sense and can be well documented by electrophysiological investigations.

The functional organization of the interictal spike complex in benign rolandic epilepsy.

PURPOSE: We studied the functional organization of the interictal epileptic spike complex in patients with benign rolandic epilepsy of childhood (BREC). METHODS: We recorded interictal epileptiform spikes and somatosensory evoked potentials after median nerve stimulation, providing a biologic marker for the location of the central sulcus in 12 patients with BREC. We used multiple dipole modeling to assess the number, the three-dimensional intracerebral location, and the time activity of the underlying neuronal sources. RESULTS: Although the interictal spike complex could be modeled by a single tangential dipolar source in seven patients (group 1), in the remaining five patients, two sources-a radial and a tangential dipole-were necessary adequately to explain the interictal spikes (group 2). The tangential source was located deeper than the radial source and was characterized by a frontal positivity and a centroparietal negativity with a phase reversal across the central sulcus, suggesting that the interictal spikes originated in the anterior wall of the central sulcus. The radial source showed a single electronegativity over the ipsilateral central region, which would be compatible with involvement of the top of either the pre- or postcentral gyrus. Both sources showed biphasic time patterns with an average latency difference of 30 ms. CONCLUSIONS: Our results indicate that in some patients with typical BREC, the interictal epileptiform spike complex is generated by multiple, simultaneously active neuronal populations within the central region and that epileptiform activity is propagated between these two adjacent cortical areas.

Somatotopy of human hand somatosensory cortex as studied in scalp EEG.

We recorded somatosensory evoked potentials (SEPs) in scalp EEGs during stimulation of the median nerve, the ulnar nerve and the individual digits in 3 normal subjects and in 1 epilepsy patient. In this patient we also measured SEPs from chronically indwelling subdural grid electrodes during electrocorticography (ECoG). We applied dipole modelling technique to study the 3-dimensional intracerebral locations and time activities of the neuronal sources underlying stimulation of different peripheral receptive fields. The sources underlying median nerve SEPs were located an average of 10.8 mm lateral inferior to those underlying ulnar nerve SEPs. Digit SEP sources showed a somatotopic arrangement from lateral inferior to medial superior in the order thumb, index finger, middle finger, ring finger and little finger, with some overlap or reversal for adjacent digits. The average distance between thumb and little finger was 12.5 mm. Thumb, index finger and middle finger were clustered around median nerve cortical representation, whereas ring finger and little finger were arranged around ulnar nerve cortex. In the epilepsy patient, the source localizations obtained in scalp EEGs showed good agreement with those on ECoGs. We conclude that SEPs recorded in scalp EEGs can be used to study functional topography of human somatosensory cortex non-invasively.

Changes of serum lipid patterns during long-term anticonvulsive treatment.

Serum lipids were determined in 97 patients (56 men, 41 women; ages 42 +/- 15 years) undergoing long-term anticonvulsive treatment (longer than 6 months). The total group showed increased total cholesterol, decreased high-density lipoprotein HDL cholesterol, an increased ratio of total to HDL cholesterol, and decreased apolipoprotein A1 and B values compared to population means. Considering males and females separately, all differences were significant (P < 0.01) in men, whereas in women only the differences in HDL cholesterol, ratio of total to HDL cholesterol, and apolipoproteins A1 and B reached the level of statistical significance. Considering the different anticonvulsant groups, cholesterol was significantly increased only in phenytoin-treated males; HDL cholesterol was significantly lowered and the ratio of total to HDL cholesterol significantly increased in all groups. Apolipoprotein A1 levels were significantly decreased in phenytoin-treated females and valproate-treated patients of both sexes. Apolipoprotein B levels were significantly decreased in all groups except carbamazepine-treated males. Especially in men treated with anticonvulsants these lipid levels may be considered a risk factor for atherosclerosis.

Occurrence of epileptiform activity in the routine EEG of epileptic patients.

In a retrospective study, the occurrence of epileptiform activity (EA) in routine EEG records of epileptic patients was investigated. Data were obtained from 1078 EEGs of 373 patients (199 men and 174 women; aged 17-87 (mean 34.2 +/-14.7)). The percentage of 38% of patients with EA in a single EEG could be increased to 77% by repeated records. After the 5th record however, the gain in new information decreased remarkably. No differences between seizure types could be detected. There was a relationship between EA and nonspecific EEG abnormalities. High EA rates were found for short time intervals since last seizure, young patients, long durations of the seizure disorder and for high seizure frequencies.

Physical activity and sports in patients suffering from Parkinson's disease in comparison with healthy seniors.

Physical activity during lifetime was investigated among 32 Parkinson patients (age 65.6 +/- 8.1 yrs, mean +/- SD) retrospectively by means of a structured interview. Data were compared with 31 healthy controls (age 61.7 +/- 5.8 yrs). An objective score was obtained by presenting a list of all kinds of sports, subjective estimation of physical activity was done by visual analogous scales. Until the occurrence of the first symptoms (mean = 58.5 yrs) the patients did not differ from controls. During the course of disease a striking reduction in physical activity but no complete abandonment of sports was found. Swimming, hiking and gymnastics were the favoured sports in both groups. Learning of new sports seemed to be impossible for the patients.

Circadian secretion pattern of melatonin in de novo parkinsonian patients: evidence for phase-shifting properties of l-dopa.

Aim of this study was the characterization of the circadian melatonin profile in de novo Parkinson patients (N = 9, age 60.0 +/- 3.2 years, mean +/- SEM) and the comparison of these profiles with those of controls and Parkinson patients treated with l-dopa/decarboxylase inhibitor (l-dopa/DCI). We collected 14 venous blood samples during a period of 24 hours and measured the serum melatonin levels by a radioimmuno assay. De novo Parkinson patients displayed the nocturnal melatonin peak (acrophase) at the same time as controls and significantly later than l-dopa/DCI treated patients (1:54 +/- 15.6 min [average clock time +/- SEM in minutes] vs. 1:45 +/- 15.6 min vs. 0:13 +/- 40.8 min). The amount of secreted melatonin did not differ among the three groups. Stage and duration of Parkinson's disease did not correlate with the amount of secreted melatonin. Patients of the tremor subgroup, however, secreted more melatonin than patients presenting only with rigidity and akinesia. The phase advance in Parkinson patients treated with l-dopa/DCI is possibly due to a central nervous dopaminergic effect elicited by l-dopa administration and not inherent to Parkinson's disease per se.

Human somatosensory cortical finger representation as studied by combined neuromagnetic and neuroelectric measurements.

We studied somatotopy of human hand somatosensory cortex using evoked responses recorded on magnetoencephalogram (MEG) and scalp-electroencephalogram (EEG) in conjunction with dipole modeling. We found a somatotopic arrangement of cortical digit representations with a sensory sequence from lateral inferior to medial superior in the anatomical order thumb, index finger, middle finger, ring finger, and little finger. MEG alone was able to reproduce this sensory sequence more accurately than scalp-EEG alone. However, the combined information provided by both techniques improved localization accuracy even further. As MEG and scalp-EEG are complementary and confirmatory techniques, this combined approach was useful to get more complete information on the functional organization of human hand somatosensory cortex.

Circadian secretion pattern of melatonin in Parkinson's disease.

Although several studies on the efficacy and the toxicity of exogenous melatonin in Parkinson patients have been carried out, there are no data available on melatonin secretion in these patients. We therefore performed a controlled trial in 9 Parkinson patients (aged 62.1 +/- 8.7 years, x +/- SD) and in 14 control persons (58.0 +/- 10.4 years). Parkinson patients were treated with l-dopa (300-1000 mg per day) in combination with a peripheral decarboxylase inhibitor (benserazide, carbidopa). 14 venous blood samples were taken from each person during a period of 24 hours in order to investigate the circadian secretion pattern of melatonin. Serum melatonin levels were estimated by radioimmuno assay. We found that the circadian secretion patterns of l-dopa-treated Parkinson patients and age-matched controls were very similar except for a phase advance of the nocturnal melatonin elevation in the parkinsonian group.

Neuromagnetic investigation of somatotopy of human hand somatosensory cortex.

In order to investigate functional topography of human hand somatosensory cortex we recorded somatosensory evoked fields (SEFs) on MEG during the first 40 ms after stimulation of median nerve, ulnar nerve, and the 5 digits. We applied dipole modeling to determine the three-dimensional cortical representations of different peripheral receptive fields. Median nerve and ulnar nerve SEFs exhibited the previously described N20 and P30 components with a magnetic field pattern emerging from the head superior and re-entering the head inferior for the N20 component; the magnetic field pattern of the P30 component was of reversed orientation. Reversals of field direction were oriented along the anterior-posterior axis. SEFs during digit stimulation showed analogous N22 and P32 components and similar magnetic field patterns. Reversals of field direction showed a shift from lateral inferior to medial superior for thumb to little finger. Dipole modeling yielded good fits at these peak latencies accounting for an average of 83% of the data variance. The cortical digit representations were arranged in an orderly somatotopic way from lateral inferior to medial superior in the sequence thumb, index finger, middle finger, ring finger, and little finger. Median nerve cortical representation was lateral inferior to that of ulnar nerve. Isofield maps and dipole locations for these components are consistent with neuronal activity in the posterior bank of central fissure corresponding to area 3b. We conclude that SEFs recorded on MEG in conjunction with source localization techniques are useful to investigate functional topography of human hand somatosensory cortex non-invasively.

[The significance of laboratory findings in long-term antiepileptic therapy]. / Bedeutung von Laboratoriumsbefunden bei Antiepileptika-Langzeittherapie.

A retrospective study of 316 patients (173 men, 143 women; mean age 39 [17-87] years) who had taken antiepileptics (phenytoin, phenobarbital, carbamazepine, valproic acid) for at least six months, was carried out to assess the biochemical and haematological changes in relation to the drug used, the therapeutic programme and the drug serum levels. The most frequent change was isolated elevation of gamma-GT (9-89% of cases depending on the drug), followed by elevation of alkaline phosphatase (16-44%). Increases in the transaminases GOT (4-13%) and GPT (4-19%) were infrequent and minor. Changes in the blood picture were very infrequent and never more than minimal. Correlation between all these changes and serum drug levels was poor (r less than 0.15). Correlations between drug serum level and dose were found in the case of phenobarbital (r = 0.6) and valproic acid (r = 0.5). There was hence no evidence of any clear connection between the biochemical findings and the serum concentrations of antiepileptic drugs or their-dosage. The results indicate that undue importance has previously been attached to routine checks of biochemical parameters; abnormal biochemical findings by themselves are not usually enough to necessitate changes in treatment. Determination of biochemical and haematological parameters is necessary only if there are clinical grounds for it such as suspicion of side effects, the occurrence of epileptic attacks despite therapy, or change from one drug to another.

Essential tremor: functional disability vs. subjective impairment.

78 patients with essential tremor (ET) were investigated to uncover correlation and discrepancies between functional (motor) disabilities and subjective impairment. Various self-rating scales (Zung, v. Zerssen etc.) were used for the assessment of the latter: 2/5 of the patients rated themselves as severely impaired; 1/3 was depressive. Patients who showed nearly the same functional (motor) disability felt very differently subjectively impaired. Semiquantitative clinical scores of action tremor correlated best with the subjective impairment in activities of daily living. Objective measurements of motor disability were performed with the "Motorische Leistungsserie nach Schoppe" (motor performance test) and showed good correlation to the subjective impairment in simple tasks of every day life, such as drinking from a glass, eating soup, and writing. Asking for the subjective impairment in these tasks allows to estimate the objective disability correctly. This may be of value in long-term studies of essential tremor.