Auditory evoked responses (AER) and augmenting-reducing phenomenon in patients with progressive supranuclear palsy (PSP)

Variations in amplitude and latency of P1, N1 and P2 waves of AER induced by increasing the stimulus intensity (augmenting-reducing) were measured in PSP patients and compared to those observed in normal subjects. The studied population included 17 patients (10 male, 7 female, mean age 66 +/- 8 yr) with a typical PSP symptomatology and 17 normal subjects (10 male, 7 female, mean age 66 +/- 9 yr). All subjects from both the groups showed a normal auditory threshold (less than 30 db SPL or a moderately increased threshold never exceeding 10 db SPL). Nine patients had normal BAER; 4 patients showed an abnormal III wave; 3 patients showed an abnormal V wave. One patient had a poorly individualized BAER. Latencies and amplitudes of P1, N1 and P2 waves derived from Cz and Fz (linked ear reference) were studied with 50, 60, 70 and 80 db intensities and for each patient slopes of amplitude-stimulus intensity and latency-stimulus intensity curves were studied. Although patients showed decreased AER amplitudes, the augmenting-reducing phenomenon was not different from controls regarding either latency or amplitude changes with increasing stimulus intensity. Previous studies had established a negative correlation between the augmenting-reducing responses and HVA levels in the cerebrospinal fluid (CSF). Similarity of augmenting-reducing mechanisms in PSP and normal subjects favors the hypothesis of unimpaired mesocortical and mesolimbic dopaminergic pathways in PSP. This hypothesis is also supported by postmortem studies using biochemical markers.     

Brainstem auditory evoked responses in 200 patients with multiple sclerosis

Brainstem auditory evoked responses (BAERs) were recorded from 202 patients with definite, probable, or possible multiple sclerosis (MS). Definitions of abnormality were based only on interwave separations and the wave I/wave V amplitude ratio. Thirty-two percent of the patients had abnormal BAERs, and the presence of clinically unsuspected lesions was revealed by BAER abnormalities in 7.4%. Thirty-five percent of the patients who had nystagmus and 53% of those who had internuclear ophthalmoplegia at the time of testing had BAER abnormalities. Forty-five percent of the abnormalities were elicited with stimulation of one ear only, stressing the importance of monaural stimulation. Click rates faster than 10 per second did not reveal abnormalities undetected at slower rates. BAERs were normal by these criteria in patients with labyrinthine diseases and amyotrophic lateral sclerosis. Thus, the BAER in MS can (1) confirm the presence of central lesions in pateints with suspected brainstem involvement, (2) document the presence of clinically unsuspected lesions, and (3) be followed over time to provide possible assistance in evaluating the effectiveness of therapeutic measures. The BAER is a useful tool in the diagnosis and management of MS.     

Multimodal evoked potentials in spinocerebellar ataxia types 1, 2, and 3

Aims:

Spinocerebellar ataxias (SCA) are a clinically heterogeneous group of disorders that are characterized by ataxia and an autosomal dominant pattern of inheritance. The aim of our study was to describe the findings of evoked potentials (EPs) among genetically proven SCA types 1, 2, and 3 and to additionally evaluate if EPs can be used to differentiate between them.

Materials and Methods:

Forty-three cases of genetically proven SCA (SCA1 = 19, SCA2 = 13, and SCA3 = 11) were evaluated with median somatosensory-EP (mSSEP), visual-EP (VEP), and brainstem auditory-evoked response (BAER) by standard procedures and compared with normative laboratory data. An EP was considered abnormal if latency was prolonged (>mean + 3 standard deviation (SD) of laboratory control data) or the waveform was absent or poorly defined. The waves studied were as follows: mSSEP - N20, VEP - P100 and BAER - interpeak latency 1-3 and 3-5.

Results:

EPs were abnormal in at least one modality in 90.9% of patients. The most common abnormality was of BAER (86.1%) followed by VEP (34.9%) and mSSEP (30.2%). The degree of abnormality in VEP, mSSEP, and BAER among patients with SCA1 was 42.1, 41.2, and 73.3%, respectively; among patients with SCA2 was 38.5, 27.3, and 100%, respectively; and among patients with SCA3 was 18.2, 37.5, and 88.9%, respectively. The differences between the subgroups of SCAs were not statistically significant.

Conclusions:

BAER was the most frequent abnormality in SCA types 1, 2, and 3; abnormalities of mSSEP were comparable in the three SCAs; whereas, abnormality of VEP was less often noted in SCA3.     

Assessment of cortico-spinal tract impairment in multiple system atrophy using transcranial magnetic stimulation.

OBJECTIVE: Among Parkinsonian syndromes, pyramidal signs suggesting cortico-spinal impairment are a hallmark of multiple system atrophy (MSA). Although it is crucial to diagnose correctly this disease to choose the appropriate treatment, the available diagnostic criteria lack sensitivity. Cortical excitability patterns assessed by transcranial magnetic stimulation (TMS) do not differentiate Parkinsonian disorders. TMS using triple stimulation technique (TST) accurately detects cortico-spinal impairment. We hypothesized that this technique could detect such impairment in MSA patients. METHODS: The TST was applied along with single and paired-pulse TMS to 31 patients fulfilling the diagnostic criteria for MSA-P (n=10), MSA-C (n=4), progressive supranuclear palsy (PSP; n=6) and Idiopathic Parkinson's disease (IPD; n=11) and 11 control subjects. RESULTS: Single and paired-pulse TMS patterns did not differ between any patient group. The TST pattern was abnormal in five MSA-P, one MSA-C and one PSP patients but not in IPD patients or controls. The mean TST ratio for MSA-P (86.6%) was significantly different from IPD (99.1%; p<0.05) whereas ratios for MSA-C (92.1%) and PSP (93.3%) were not different from IPD or controls (99.5%). CONCLUSIONS: These results suggest that TST is effective to assess cortico-spinal impairment in MSA. SIGNIFICANCE: TST might be useful for the diagnosis of atypical Parkinsonism.     

Sleep disturbances and brain MRI morphometry in Parkinson's disease,multiple system atrophy and progressive supranuclear palsy – a comparative study

Despite common reports in Parkinson's disease (PD), in other parkinsonian syndromes, sleep disturbances have been less frequently described. This study evaluated and compared sleep disturbances in patients with PD, multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) and analyzed associations with brain magnetic resonance imaging (MRI) morphometry. This was a cross-sectional study of 16 PD cases, 13 MSA, 14 PSP and 12 control. Sleep disturbances were evaluated by Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index (PSQI), Restless Legs Scale and Berlin questionnaire. Pons area, midbrain area, medial cerebellar peduncle (MCP) width, and superior cerebellar peduncle width were measured using MRI. Poor quality sleep, risk of obstructive sleep apnea (OSA) and restless legs syndrome (RLS) were detected in all groups. Patients with MSA showed higher risk of OSA and less frequent RLS. In MSA, a correlation between PSQI scores and Hoehn and Yahr stage was observed (p < 0.05). In PSP, RLS was frequent (57%) and related with reduced sleep duration and efficiency. In PD, excessive daytime sleepiness was related to atrophy of the MCP (p = 0.01). RLS was more frequent in PD and PSP, and in PSP, was associated with reduced sleep efficiency and sleep duration. Brain morphometry abnormalities were found in connection with excessive daytime sleepiness and risk of OSA in PD and PSP suggesting widespread degeneration of brainstem sleep structures on the basis of sleep abnormalities in these patients.     

Qualitative postural control differences in Idiopathic Parkinson’s Disease vs. Progressive Supranuclear Palsy with dynamic-on-static platform tilt

Objectives

We aimed to assess whether postural abnormalities in Progressive Supranuclear Palsy (PSP) and Idiopathic Parkinson’s Disease (IPD) are qualitatively different by analysing spontaneous and reactive postural control.

Reversal of long term potentiation-like plasticity in primary motor cortex in patients with progressive supranuclear palsy

Objective

Abnormal primary motor cortex plasticity might be involved in the pathophysiology of progressive supranuclear palsy. In the present study we aimed to investigate possible abnormalities of depotentiation, a mechanism involved in plasticity regulation, in this condition.

Comparison of interwave latencies of brain stem auditory evoked responses in narcoleptics, primary insomniacs and normal controls.

A study of brain stem auditory evoked responses (BAER) was carried out in 10 narcoleptics, 10 primary insomniacs and 10 normal controls to determine if a neurophysiologic abnormality could be detected in these primary sleep disorders. The mean interpeak conduction times of Wave I-III, III-V and Iv were compared between the following groups: normal controls awake and in monitored sleep; narcoleptics awake and in monitored sleep, normal controls awake and narcoleptics awake; normal controls awake and insomniacs awake; narcoleptics awake and insomniacs awake; narcoleptics with cataplexy (n = 6) awake and narcoleptics without cataplexy (n = 4) awake. No significant differences were found which suggests that these sleep disorders represent dysfunctions which do not involve brain stem structures subserving the BAER.     

Comparison of REM sleep behaviour disorder variables between patients with progressive supranuclear palsy and those with Parkinson's disease

PurposeRapid eye movement (REM) sleep behaviour disorder (RBD) is an important indicator of underlying synucleinopathies. However, the frequency of RBD in tauopathies such as progressive supranuclear palsy (PSP) remains unclear. In this study, we compared RBD-related symptoms and polysomnographic (PSG) findings between patients with PSP and those with Parkinson’s disease (PD).MethodsWe conducted clinical interviews of 20 patients with PSP, 93 patients with PD and their caregivers regarding RBD-related symptoms, and conducted PSG recordings on all the subject patients. We then compared the clinical backgrounds, PSG parameters, and frequency of RBD-related symptoms between the two groups.ResultsPSP patients had more severe symptoms of Parkinsonism and cognitive impairment, and took lower doses of dopaminergic agents compared with PD patients. The PSP group had lower values for both estimated total sleep time and sleep efficiency on PSG compared with the PD group (p = 0.002, p = 0.021, respectively). The PSP group also included a significantly smaller number of patients having REM sleep without atonia (RWA) compared with the PD group (n = 5, 20.0% vs. n = 56, 60.2%, p = 0.003). None of the PSP patients were experiencing RBD-related symptoms at the time of the investigation, while 30 PD patients (32.3%) had RBD-related symptoms.DiscussionThe existence of RWA as well as RBD-related symptoms was less frequent in patients with PSP versus patients with PD. Differences in brain stem pathology and/or disease course between the two disorders might influence this difference.     

Electrophysiological features of lower motor neuron involvement in progressive supranuclear palsy

BackgroundAbnormalities of the spinal cord were considered uncommon in progressive supranuclear palsy (PSP), and therefore spinal symptoms were not included among PSP characteristic features. However there have been some neuropathological reports of spinal cord lesions in patients with PSP. The aim of our study was to find out if the possible lower motor neuron involvement in PSP is reflected by electromyographic (EMG) and/or electroneurographic (ENG) abnormalities.Material24 patients with clinically probable PSP (mean age 67.5 yrs; 66% males) were included in the study. The control group for ENG studies consisted 25 age matched healthy volunteers.MethodsNerve conduction studies in the ulnar, peroneal and sural nerves and EMG of the first interosseus dorsal and tibial anterior muscles were performed.ResultsThe only ENG abnormality observed was decreased compound muscle action potential (CMAP) and sensory nerve action potential (SNAP) amplitudes in the ulnar nerve. Such decrease was registered in 8.3% and 20% of PSP patients respectively. There was no significant difference between the values of ENG parameters between PSP patients and the control group. In EMG abnormalities suggesting chronic reinnervation were recorded in the first interosseous dorsal (FID) muscle in 45.8%, and in the tibialis anterior (TA) muscle in 37.5% of PSP patients. A significant correlation was found between the age of PSP patients and their mean motor unit potential (MUP) amplitude in TA muscle (p = 0.04) and also between the age of onset and MUP amplitude in both, the TA and FID muscles (p = 0.026 and p = 0.03 respectively).ConclusionsIn PSP, neurogenic EMG abnormalities in skeletal muscles are present in nearly half the patients suggesting a loss of motor neurons in the anterior horns of the spinal cord which is in line with our histopathological findings. In contrast, electrophysiological signs of neuropathy in peripheral nerves in PSP are very rare. Concluding, although PSP is characterized by the pathological process in specific basal ganglia and brainstem areas, our electromyographic study suggests the need for broadening the spectrum of PSP for lower motor neurons degeneration.     

Effects of sleep deprivation on cortical excitability in patients affected by juvenile myoclonic epilepsy: a combined transcranial magnetic stimulation and EEG study

OBJECTIVE: To investigate the effect of sleep deprivation on corticospinal excitability in patients affected by juvenile myoclonic epilepsy (JME) using different transcranial magnetic stimulation (TMS) parameters. METHODS: Ten patients with JME and 10 normal subjects underwent partial sleep deprivation. Motor threshold (MT), motor evoked potential amplitude (MEP), and silent period (SP) were recorded from the thenar eminence (TE) muscles. Short latency intracortical inhibition (SICI) and short latency intracortical facilitation (SICF) were studied using paired magnetic stimulation. TMS was performed before and after sleep deprivation; EEG and TMS were performed simultaneously. RESULTS: In patients with JME, sleep deprivation induced a significant decrease in SICI and an increase in SICF, which was associated with increased paroxysmal activity. A significant decrease in the MT was observed. No significant changes in any TMS parameters were noted in normal subjects after sleep deprivation. The F wave was unchanged by sleep deprivation in both control subjects and in patients with JME. CONCLUSIONS: In patients with JME, sleep deprivation produces increases in corticospinal excitability in motor areas as measured by different TMS parameters.     

The auditory startle response in parkinsonism may reveal the extent but not type of pathology

OBJECTIVES: We measured the acoustic startle response (ASR) and blink reflex (ABR) in patients with clinically diagnosed Parkinson's disease (PD) and progressive supranuclear palsy (PSP) and determined the specificity of an abnormal result for the diagnosis of PSP. METHODS: Thirty patients (11 PD, 19 PSP) and 12 age matched controls were studied. The PSP group was separated into clinical subgroups. Fourteen patients with early falls, cognitive dysfunction and eye movement abnormalities were classified as Richardson's disease (RD), 3 with parkinsonism in the absence of early falls, cognitive dysfunction or eye movement abnormalities were classified PSP-parkinsonism (PSP-P) and 2 who presented with gait unsteadiness and freezing without cognitive dysfunction or eye movement abnormalities were classified as pure akinesia with gait freezing (PAGF). Following an acoustic startle stimulus EMG activity was recorded in the orbicularis oculi and sternomastoid muscles. The likelihood ratio of an absent response being clinically diagnosed PSP was determined. RESULTS: The ABR was present in 11/19 (58%) of patients with PSP, and 11/11 with PD and 12/12 controls (H2 p < 0.05). The ASR measured at the sternomastoid was present in only 2/19 (11%) of patients with PSP, but in 5/11 (45%) with PD and 6/12 (50 %) controls (H2 p < 0.05). The ABR was present in only 6/14 (43%) of the RD group, but in 3/3 PSP-P and 2/2 PAGF. Loss of the ABR was 100% specific for PSP, but only 42 % sensitive. Loss of the sternomastoid ASR had a likelihood ratio of 1.9 for the clinical diagnosis of PSP. CONCLUSIONS: The ASR and ABR appear unlikely to be useful in differentiating PSP from PD.Abnormalities in these responses are worse in RD where the pathology is known to be more widespread than in PSP-P and PAGF.     

进行性核上性麻痹与多系统萎缩的头部MRI和FDG-PET比较

目的对比研究进行性核上性麻痹(PSP)与多系统萎缩(MSA)的脑干MRI表现和头部葡萄糖代谢特征。方法对11例PSP患者、37例MSA患者和43例健康对照进行头部MRI平扫检查,并计算MRI正中矢状面T1加权像上中脑截面面积,其中5例PSP和19例MSA进行了18F-FDG PET检查。结果(1)MRI:11例PSP正中矢状位T1加权像均可见中脑上缘平坦或凹陷表现,呈"蜂鸟征",而MSA患者和健康对照组未见上述表现。37例MSA患者中有34例轴位T2加权像桥脑可见"十字征"样长T2异常信号。PSP患者正中矢状位T1加权像上中脑截面面积分别低于MSA组和健康对照组(P<0.01)。(2)PET:PSP组主要表现为对称性额叶低代谢;MSA组主要表现为额、顶、颞叶普遍低代谢,纹状体对称性代谢降低,丘脑代谢高于纹状体。结论PSP中脑MRI特征和头部葡萄糖代谢特征与MSA和健康对照有明确差异,有助于PSP与MSA的鉴别诊断。     

'Benign focal epilepsy in infancy with vertex spikes and waves during sleep'. Delineation of the syndrome and recalling as 'benign infantile focal epilepsy with midline spikes and waves during sleep' (BIMSE)

PURPOSE: To better delineate the electroclinical features of infants who presented with focal seizures and typical midline sleep EEG abnormalities with a benign outcome. We discuss the significance of the typical EEG marker in non-epileptic patients. METHODS: Patients were selected from a group of epileptic subjects with seizure onset less than 3 years we observed from 1st November 1990 and 31st December 2003. Inclusion criteria were the presence of typical sleep EEG marker and focal seizures with benign outcome. Cases with less than 18 month follow-up period were excluded from this study. RESULTS: There were 19 patients (12 males, 7 females). Pre-, peri- and post-natal personal history was negative in all patients. Psychomotor development was normal, both before and after seizure onset. Neuroradiological investigations gave normal results. Seizure manifestations were typical, characterized by cyanosis, staring and rare lateralizing signs, of short duration. Age at onset was comprised between 4 and 30 months. The typical EEG marker, a spike followed by a bell-shaped slow-wave, localized in the midline regions, was present in all subjects only during sleep. All had a favorable outcome and the overwhelming majority of the patients were not treated. CONCLUSIONS: Our patients have an homogeneous electroclinical picture to constitute a new epileptic syndrome not included in the ILAE classification. We propose to call it 'benign focal epilepsy in infancy with midline spikes and waves during sleep' (BIMSE).     

The impact of epilepsy on sleep architecture during childhood

Purpose: The effect of etiology on the relationship between epilepsy and sleep during childhood has not been studied in detail. The aim of this study was to evaluate differences in sleep structure in drug-resistant epilepsies with different underlying causes. Methods: We studied 31 patients with drug-resistant epilepsies with or without a structural lesion (lesional and nonlesional) and compared their sleep architecture with that of normal controls and with that of a group of children with benign epilepsy with rolandic spikes (BERS). Subjects underwent a single-night polysomnographic recording. Sleep recordings were scored according to the American Academy of Sleep Medicine (AASM) and cyclic alternating pattern (CAP) criteria. Key Findings: Compared to normal controls, patients with drug-resistant epilepsy showed a significant reduction of time in bed, total sleep time, rapid eye movement (REM) sleep, sleep stage N3, and sleep efficiency, and a significant increase in wake after sleep onset. The lesional subgroup showed a reduction in total sleep time and sleep latency and an increase in REM latency and wake after sleep onset. No significant differences, however, were found comparing the lesional and nonlesional subgroups. When compared to BERS, patients with drug-resistant epilepsy showed a significant reduction in sleep stage N3, REM sleep, and sleep efficiency. Regarding CAP analysis, when compared to controls, the drug-resistant group had an increased A1% and a decreased A2%, with a decrease of A1 index in N3 and a global decrease of A2 and A3 indexes. The lesional subgroup showed a slight increase of A1% with a decrease of A1 index in N3 and a global decrease of A2 and A3 indexes. Drug-resistant epilepsy, compared to benign epilepsy showed an increase of CAP rate in N2 and of A1 index in N1 and N2 but not in N3; A2 and A3 indexes were similar in both, but patients with drug-resistant epilepsy showed a significant reduction of A3 index in N1. Significance: Our findings suggest that the presence of structural cerebral abnormalities may play an important role in disrupting sleep architecture.     

Early brain-stem auditory evoked responses in vertebrobasilar transient ischemic attacks

Brain-stem auditory evoked response (BAER) studies were performed one to 16 days after a vertebrobasilar transient ischemic attack (VB TIA) in eight patients and repeated two to 16 days later in six of them. Initially, all showed absence of waveforms, prolonged interpeak latencies, and/or amplitude reduction. Five of six patients showed reversal of BAER changes to normal; the remaining patient returned to near normal. Normalization occurred six to 24 days after the VB TIA. These results are different from those reported in other studies. Early sequential BAER studies may be helpful in differentiating VB TIA from brain-stem infarction and syndromes that mimic VB TIA.     

Unilateral focal lesions in the rostrolateral medulla influence chemosensitivity and breathing measured during wakefulness, sleep, and exercise

OBJECTIVES: The rostrolateral medulla (RLM) has been identified in animals as an important site of chemosensitivity; in humans such site(s) have not been defined. The aim of this study was to investigate the physiological implications of unilateral lesions in the lower brainstem on the control of breathing. METHODS: In 15 patients breathing was measured awake at rest, asleep, during exercise, and during CO(2) stimulation. The lesions were located clinically and by MRI; in nine patients they involved the RLM (RLM group), in six they were in the pons, cerebellum, or medial medulla (Non-RLM group). All RLM group patients, and three non-RLM group patients had ipsilateral Horner's syndrome. RESULTS: Six of the RLM group had a ventilatory sensitivity to inhaled CO(2) (V/P(ET) CO(2)) below normal (group A: V/P(ET) CO(2), mean, 0.87; range 0.3-1.4 l. min(-1)/mm Hg). It was normal in all of the non-RLM group (group B: V/P(ET) CO(2), mean, 3.0; range, 2.6-3.9 min(-1)/mmHg). There was no significant difference in breathing between groups during relaxed wakefulness (V, group A: 7.44 (SD 2.5) l.min(-1); group B: 6.02 (SD 1.3) l.min(-1); P(ET) CO(2), group A: 41.0 (SD 4.2) mm g; group B: 38.3 (SD2.0) mm Hg) or during exercise (V/VO(2): group A: 21 (SD 6. 0) l.min(-1)/l.min(-1); group B: 24 (SD 7.3) l.min(-1)/l.min(-1)). During sleep, all group A had fragmented sleep compared with only one patient in group B (group A: arousals, range 13 to > 60 events/hour); moreover, in group A there was a high incidence of obstructive sleep apnoea associated with hypoxaemia. CONCLUSION: Patients with unilateral RLM lesions require monitoring during sleep to diagnose any sleep apnoea. The finding that unilateral RLM lesions reduce ventilatory sensitivity to inhaled CO(2) is consistent with animal studies. The reduced chemosensitivity had a minimal effect on breathing awake at rest or during exercise.     

Longitudinal ocular motor study in corticobasal degeneration and progressive supranuclear palsy

OBJECTIVE: To evaluate the usefulness of ocular motor information in the early diagnosis of corticobasal degeneration (CBD) and progressive supranuclear palsy (PSP). METHODS: Seven PSP patients, six CBD patients, and three atypical CBD patients were followed longitudinally with repeated electrooculographic (EOG) recordings, at 6-month intervals, to search for features that could confirm or modify the diagnosis. Visually guided saccades and antisaccades were studied. Data from clinical evaluations were independently collected. RESULTS: PSP patients had decreased saccade velocity throughout the disease course. Patients with probable CBD showed preserved saccade velocity but important increased saccade latency ipsilateral to the apraxia side. Similar to patients with PSP, those with atypical CBD features exhibited clinically evident abnormalities of vertical saccades and early slowing of horizontal saccade velocity, but no increase in saccade latency or early square-wave jerks. When clinical "telltale signs" appeared and the clinical diagnosis was reviewed independent of EOG recording, the three patients with atypical CBD features were diagnosed as having PSP although new or overlapping syndromes cannot be excluded. CONCLUSIONS: Consecutive EOG recordings help diagnose atypical CBD and PSP disorders earlier.     

Sleep and the cholinergic rapid eye movement sleep induction test in patients with primary alcohol dependence.

BACKGROUND: The present study investigated polysomnographically assessed sleep parameters in alcohol-dependent patients after withdrawal and in healthy control subjects during baseline and after a cholinergic stimulation paradigm. The aim of the study was to test whether sleep parameters, especially rapid eye movement (REM) sleep variables, may serve as predictors for relapse in alcohol-dependent patients. METHODS: Forty patients diagnosed with alcohol dependence were admitted to a specialized ward for alcohol withdrawal and were investigated by polysomnography at three time points: 2-3 weeks after withdrawal (T0) and at follow-up investigations 6 (T1) and 12 (T2) months after discharge from the hospital. A subgroup of patients (n = 17) was studied at T0 after challenge with galanthamine, a reversible cholinesterase inhibitor (cholinergic REM induction test, CRIT). Patients were compared with two control groups: a) 30 healthy control subjects (matched for age- and gender-distribution) for comparison at baseline conditions; and b) 17 age- and gender-matched control subjects for comparison with the CRIT. RESULTS: At baseline the patients showed significant disturbances of sleep continuity and sleep architecture (decreased slow-wave sleep, SWS) and exhibited an increase of "REM sleep pressure" (a combined index of REM latency, REM density, and REM sleep percent). Galanthamine provoked significant alterations of sleep continuity, sleep architecture (reduced SWS), and increased most of the components of REM pressure, taking patients and control subjects together. Apart from SWS %SPT (sleep period time) no significant drug-group interactions occurred. Patients who remained abstinent (n = 11) for at least 6 months at follow-up exhibited significantly less abnormalities of REM sleep at T0 compared to the group of patients that relapsed at 6 months follow-up. CONCLUSIONS: It is concluded that increased REM sleep pressure after alcohol withdrawal is a robust predictor of vulnerability to relapse. Thus, a subgroup of alcoholic patients appears to exhibit distinct neurobiological abnormalities assessable by polysomnography that are related to an increased vulnerability for alcoholism and early relapse.     

Evoked potentials in hereditary spastic paraplegia

Pattern reversal visual evoked response (VER) and monaural stimulation of brainstem auditory evoked responses (BAER) were recorded from both sides in 25 patients (males 19; females 6) with hereditary spastic paraplegia (HSP). Their age ranged from 15–52 (mean±SD; 25.2±22.5) years and duration of symptoms 6 months-9 (mean±SD; 4.2±3.6) years. A prolonged P 100 latency was seen in 6 patients and BAER abnormality in 13. None of the patients had clinical evidence of brainstem involvement. It is suggested that VER and BAER abnormalities are due to segmental demyelination and fiber loss in central conduction pathways and could serve as an important tool for the diagnosis of this disorder.

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Sommario I potenziali evocati visivi (VER) e uditivi del tronco (BAER) sono stati registrati bilateralmente in 25 pazienti (19 maschi e 6 femmine) affetti da paraplegia spastica ereditaria (HSP). La loro età media era compresa tra 15 e 52 anni (media±DS=25.2±22.5) e con una durata di malattia compresa tra 6 mesi e 9 anni (media±DS=4.2±3.6). In 6 pazienti è stato riscontrato un aumento della latenza della P100 e in 13 i BAER erano anormali. Nessuno dei pazienti presentava segni clinici di coinvolgimento del tronco. Viene ipotizzato che le anormalità osservate ai VER e BAER sono dovute ad una demielinizzazione segmentaria o a perdita di fibre lungo le vie di conduzione cerebrale. Questi esami strumentali sarebbero quindi di grande utilità nella diagnosi di HSP.