Isolated hypoglossal nerve palsy due to an anomalous vertebral artery course: report of two cases.

The authors report two patients with isolated unilateral tongue atrophy. Magnetic resonance imaging (MRI) of the brain stem and angio-MRI demonstrated a dolichovertebral artery with an abnormal course compressing the medulla oblongata at the emergence of the hypoglossal rootlets. The semeiological observation of a sectorial and not uniform distribution of atrophy in the half-affected tongue is discussed in relation to the lesional site.

Median nerve middle-long latency somatosensory evoked potentials in children with tactile evoked spikes.

It is known that hand tapping during electroencephalography (EEG) recording evokes centrotemporal spikes in some 4- to 12-year-old children. This phenomenon occurs in both healthy and epileptic children. The same children were reported to show giant middle-long latency evoked potentials (MLSEPs). To study the relationship between tactile evoked spikes (TES) and MLSEPs, we performed a neurophysiologic investigation in 25 children with TES and in 25 children without any EEG abnormality. Such an investigation included a MLSEP study after both electrical and tactile stimulation with simultaneous recording of digital EEG. MLSEPs consistently showed three negative (NI, NII, NIII) and two positive (PI, PII) peaks. Children with TES had MLSEPs of enlarged amplitude. The analysis of MLSEPs and TES characteristics led us to the conclusion that they are the same neurophysiologic event, with NII being the evoked spike and NIII the following slow-wave.

Telephone transmission of 20-channel digital electroencephalogram using lossless data compression.

BACKGROUND: The use of telecommunications for computer-assisted transmission of neurophysiological signals is a relatively new practice. With the development of digital technology, it is now possible to record electroencephalograms (EEGs) in digital form. Previous reports have demonstrated the possibility of real-time telephone transmission of a limited number of EEG channels. OBJECTIVES: To assess the effectiveness of specific data-compression software to improve the transmission of digital 20-channel EEG records over ordinary public telephone lines. METHODS: A prototype system was built to transmit digital EEG signals from one computer to another using two 14.4-kbps modems and proprietary lossless data-compression software. RESULTS: Forty compressed digital EEG records of 20 channels each were sent from different locations at variable distances using "plain old telephone service" (POTS). The mean compression ratio was 2.2 to 2.8:1 using a sampling frequency of 128 Hz and 2.8:1 at a sampling rate of 256 Hz. Transmission time was reduced proportionately. CONCLUSION: Although this study used a store-and-forward approach, the results suggest that it may be possible to transmit a large number of compressed EEG channels in real time using data compression.

Endocrine function changes in young males during long-term antiepileptic therapy with phenobarbitone and carbamazepine.

The effects of long-term antiepileptic combined therapy with phenobarbitone (PB) and carbamazepine (CBZ) on the major endocrine functions were evaluated in a selected group of 15 young males with partial epilepsy. The plasma basal levels of triiodothyronine (T3), thyroxine (T4), free thyroxine (FT4), thyrotropin (TSH), cortisol (CO), dehydroepiandrosterone-sulfate (DHEA-S), adrenocorticotropin (ACTH), growth hormone (GH), prolactin (PRL) and testosterone (T) were determined. TSH and PRL were also assessed in response to i.v. injection of thyrotropin releasing hormone (TRH). The results were compared with those found in 37 age-matched male volunteers. The most remarkable changes affected pituitary-thyroid axis and pituitary-adrenal axis, while the hypothalamic-pituitary response was normal. No correlation between hormonal changes and duration of epilepsy and therapy or ADs plasma levels was found. There seems to be considerable individual variability of response to antiepileptic therapy, probably depending on peripheral changes in the hormonal metabolism.

Multifactorial etiological aspects of epilepsy.

The results of a computerized analysis of 555 newly recognized idiopathic epilepsy patients (301 males and 254 females) are presented. All patients were under 30 years over the period 1980-1985. The possible prenatal and perinatal risk factors (RFs) for epilepsy were investigated. The data showed that 307 patients (55.5%) had possible RFs; 162 had one possible RF, 145 two or more. The association of two or more RFs had a high frequency in secondary generalized epilepsy (66.6%) and in partial epilepsy. A multifactorial etiology of epilepsy is suggested, hypothesizing a connection either between prenatal and perinatal RFs or between multiple perinatal RFs.