Læknablaðið : fylgirit - 01.05.2002, Blaðsíða 27

ABSTRACTS / 33RD SNC & 2ND SCNN
Table 1. Effect on seizure frequency of add-on topiramate in mentally retarded with MTS
Patient MRI Seizures before TPR TPR started and combinated with Other AED in 2002 Seizure frequency on topiramate
PR, f, 45y right MTS heteropia in left frontal lobe 2-6 psychomotor long seizures/ month 1/1997, VPA, OXC, VGB, AZ OXC, AZ no seizures, tickling sensations in forehead
Fl, m, 58y right MTS, cortical and cerebellar atrophy 2 long psychomotor 1/2001 VPA, CBZ CBZ 1/month, no tremor and nausea after VPA withdrawal
JR, m, 41y right MTS, cortical and cerebellar atrophy 3-6 psychomotor long seizures/ year VPA, OXC, PB, VGB OXC, small dose of PB one seizure in 8/2001
IV, m, 41y left MTS, left hemisphere atrophic 15 psychomotor seizures/month VPA, OXC CBZ, small dose of VPA 4-5/month
KV, m, 27y right MTS psychomotor 5/ year, aggression bursts CBZ no seizures, less aggressive behaviour
lying stimulus detection. Our previous results indicate that preatten-
tive auditory processing is delayed in aging and in Alzheimer’s
disease (AD), and that in young subjects it is modulated by scopol-
amine, a centrally acting cholinergic antagonist. Existing results also
suggests that scopolamine administration gives rise to temporary
cognitive dysfunction in aged subjects. It has remained unsettled,
however, whether scopolamine effects on preattentive auditory
processing underlying stimulus detection in elderly subjects.
Material and methods: We measured simultaneously electric and
magnetic responses to monaurally presented tones with electro-
encephalogram and 122-channel whole-head magnetometer from
nine non-demented elderly subjects after intravenous injection of
scopolamine or glycopyrrolate, which served as a placebo drug
being a peripherally acting cholinergic antagonist. A random, cross-
over desing was employed and the drugs were administrated using
a double blind protocol.
Results: Scopolamine significantly delayed both electric and
magnetic P50 and N100 responses, and augmented electric and
magnetic P50 responses. In contrast, following electric P200
response was not affected by scopolamine.
Conclusions: Our results indicate that the cholinergic system modu-
lates auditory processing underlying stimulus detection in elderly
subjects. Additionally, generators of separate ERP components ap-
pear to have different age-related sensitivities to scopolamine ad-
ministration. Given that preattentive auditory processing is delayed
in AD, the combined MEG/EEG measurements could be used to
monitor cholinergic cortical activity in aging and in dementia.
28 - The variability of epidermal nerve fiber densities in healthy
individuals
Mellgren Sl, Göransson L, Omdal R, Skjesol A, Lindal S
Dept. of Neurology, University Hospital of North Norway, Tromso. Norway
Background: Quantification of epidermal nerve fibers has proved
to be a valuable tool in the investigation of small fiber neuropathies.
Objective. To establish epidermal nerve fiber densities in different
age groups, search for possible changes with age and comparison of
nerve fiber densities in females and males.
Methods: Two 3 mm skin biopsies were obtained with a punch
needle ca. 10 cm superior to the lateral malleolus of the right leg of
106 healthy individuals (66 females and 40 males). Fifty micron
l'rozen sections were immunostained with 0.8% rabbit polyclonal
antibody to the human peptide protein gene product (PGP) and the
number of nerve fibers were recorded as the mean of counts per
mm in six sections, three from each of the two biopsies.
Results: The mean number of ENF was 12.4 per mm, median 11.5
(range 4.5-26.5). There was a modest, but signficant decrease of
fiber density with age (r=-0.332, p=0.0005). In females the mean
density was 13.6 and median 13.6 (5.9-26.5) and in males mean 10.5,
rnedian 9.8 (4.5-22.8) (p=0.0005).
Conclusion: There is a considerable variation of epidermal nerve
fiber densities in healthy individuals, but we also showed a modest,
but significant decrease with age, and that males had lower epider-
mal nerve fiber density than females. The latter observation may
implicate that males are more subjected to factors known to cause
peripheral neuropathy. Age and sex differences of normal ranges
should be taken into consideration when cut off values of epidermal
nerve fiber densities indicating neuropathy are determined.
30 - Olfactory Function in Neurodegenerative Disease
Hawkes C
Oldchurch Hospital, Essex Neuroscience Centre, Romford, United Kingdom
There has been a gradual increase of interest in olfactory dysfunc-
tion since it was realised that anosmia was a common feature of
idiopathic Parkinson’s disease [IPD] and Alzheimer-type dementia
[AD]. It is an intriguing possibility that the first sign of a disorder
hitherto regarded as one of movement or cognition may be that of
disturbed smell sense. In this review of IPD, parkinsonian synd-
romes, essential tremor, AD, motor neurone disease [MND] and
Huntington’s chorea [HC] the following observations are made: 1)
olfactory dysfunction is frequent and often severe in IPD and AD
2) normal smell sense in IPD is rare and should prompt review of
Læknablaðið/Fylgirit 43 2002/88 27