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H P Cathala

Publications and source records attributed to H P Cathala.

At least 19 recordsLinked to original sources
PubMed1991

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.

Aged↗
PubMed1990

[Detection and peripheral or central localization of sensory pathway involvement of the lower limbs by somatosensory evoked potentials].

In the presence of more or less atypical sensory or sensorimotor symptoms the questions that arise most frequently concern the authenticity of the disorders and the precise level of the lesion. In this study, somatosensory evoked potentials (SEPs) to stimulation of the tibial nerve at the ankle were recorded at different levels in 35 healthy subjects and 32 patients with sensory disorders. Recording electrodes were placed at the popliteal fossa (peripheral sensory nerve conduction velocity), at the T12-L1 level (medullary potential: N21) and at the vertex (P40 wave). The spine to cortex time interval was measured. A systematic study of evoked responses to median nerve stimulation was performed. The 32 patients were divided into 4 groups: Group I (3 cases) had slowed sensory conduction velocity (SCV), similar delay in N21 latency and normal N21-P40: peripheral neuropathy. Group II (4 cases) had normal SCV, delayed N21 latency and normal N21-P40: radicular or conus medullaris injury. Group III (19 cases) had normal SCV, normal N21 latency and lengthened N21-P40 interval. A study of responses to median nerve stimulation made it possible to discriminate between spinal and cortical or subcortical impairment. Group IV (6 cases) had abnormalities from any two of the three groups defined above. In 24 out of 32 patients (75 p. 100), further investigations (myelography, MRI, EMG) confirmed the localization determined by evoked responses. In the other 8 patients (25 p. 100) whose clinical picture suggested a medullary or radicular impairment, SEPs alone clearly revealed an injury. SEPs can distinctly show a spinal impairment and determine the choice of further investigations.

Adult↗
PubMed1989

Peripheral neuropathies during treatment with almitrine: report of 46 cases.

Almitrine bismesylate is thought to cause sensory peripheral neuropathy. Forty-six patients are reported who received almitrine bismesylate alone for chronic respiratory failure or in combination with raubasine for various cerebrovascular diseases. Polyneuropathy appeared between 9 and 25 months after the onset of treatment. Sensory signs and symptoms were confined to the distal parts of the lower limbs and involved large and small fibres. Histological and electrophysiological findings indicated axonal degeneration. Respiratory failure could have caused the polyneuropathy in some cases but many had no chest disease. Patients began to improve between 3 and 6 months after withdrawal of the drug. Recovery was usually complete after 12 months.

Aged↗
PubMed1989

[Efficacy of uvulopalatopharyngoplasty (UPPP) and modifications in sleep structure in the sleep apnea syndrome (SAS)].

Thirty-four patients (32 male, 2 female; mean age 53 +/- 7 years) with confirmed sleep apnea syndrome (SAS) were studied before and after uvulopalatopharyngoplasty (UPPP). Clinical symptoms were tiredness, excessive daytime sleepiness and snoring. All patients were overweight. Patients underwent a thorough physical and oropharyngeal examination and polysomnography before and 3 months after surgery. On the basis of post-operative results, patients are divided into 3 groups: --group 1: 16 cured patients: apnea index (A.I./h) 38 +/- 17 before and 4.4 +/- 4 apneas/h sleep after surgery. Improved nocturnal hypoxemia: mean minimum oxyhemoglobin saturation (SAO2) before and after UPPP in NREM sleep 83 +/- 4% v. 90 +/- 4% in REM sleep 76 +/- 11% v. 85 +/- 7%. Uninterrupted sleep is restored; --group 2: 8 improved patients: A.I./h of 64 +/- 11 before and 20 +/- 6 after UPPP: improved nocturnal hypoxemia: mean minimum SAO2 in NREM sleep 74 +/- 10% before and 86 +/- 6% after UPPP: in REM sleep 59 +/- 9% before and 79 +/- 6% after UPPP, lower amount and percentage of fragmented sleep; --group 3: 10 non-improved patients: A.I./h unchanged 55 +/- 22% before and 50 +/- 20% after UPPP. Persistent nocturnal hypoxemia: mean minimum SAO2 in NREM sleep 76 +/- 13 before and 81 +/- 12% after UPPP: in REM sleep 63 +/- 16% before and 65 +/- 24% after UPPP. Sleep remains fragmented. In this last group patients are more overweight and all suffer from severe SAS with greater nocturnal oxyhemoglobin desaturation. Surgical treatment by UPPP is shown to be effective for 70% of our patients. Better results are obtained when SAS is less severe and overweight less important.

Adult↗
PubMed1989

Effect of age on auditory evoked responses (AER) and augmenting-reducing.

Auditory evoked responses (AER) were obtained from Cz and Fz in 30 adults (14 male, 16 female) from 20-80 years old. Sound bursts (1000 Hz-200 msec) of four different intensities were used. Peak to trough amplitudes of P1N1 and N1P2 and latencies of P1, N1 and P2 peaks were measured with increasing stimulus intensity and slopes of amplitude - intensity and latency - intensity curves were analysed for assessment of an age effect. The main result is that the increase in P1N1 amplitude with increasing stimulus intensity is more pronounced in older persons. Previous studies have established a negative correlation between the augmenting-reducing responses and HVA levels in the CSF (with lower amounts of HVA in the CSF of "augmenters"). Decreased dopamine metabolism in old subjects could account for our results, so further studies should focus on patients with pathological dopamine deficiencies.

Acoustic Stimulation↗
PubMed1989

The spectrum of polyneuropathies in patients infected with HIV.

Twenty five patients with peripheral neuropathy at different stages of human immunodeficiency virus (HIV) infection are reported. Cerebrospinal fluid (CSF) findings were available in 17 cases, electrophysiology in all and a neuromuscular biopsy in 11. Of six otherwise asymptomatic HIV+ patients, five had chronic inflammatory demyelinating polyneuropathy (CIDP) and one acute inflammatory demyelinating polyneuropathy (AIDP). CSF showed pleocytosis in all cases. Infiltration of the endoneurium and/or the epineurium by mononuclear cells was seen in biopsies from three cases. These six patients recovered either spontaneously, or with corticosteroids or plasmaphereses. Of five patients with AIDS related complex (ARC), three had distal predominantly sensory peripheral neuropathy (DSPN), one CIDP and one mixed neuropathy. Of 14 patients with AIDS, one had mononeuropathy multiplex and 13 painful DSPN. Electrophysiological studies were consistent with an axonopathy. Nerve biopsies in six cases showed axonal changes but surprisingly associated with marked segmental demyelination in two cases. Cell infiltration was present in nerve samples in two cases. Five patients died within six months after the onset of the neuropathy.

AIDS-Related Complex↗
PubMed1989

Cervical magnetic stimulation: a new painless method for bilateral phrenic nerve stimulation in conscious humans.

Assessing diaphragmatic contractility is a common goal in various situations. This assessment is mainly based on static or dynamic maximal voluntary maneuvers and twitch transdiaphragmatic pressures (Pdi) obtained by stimulation of the phrenic nerves (PS). PS eliminates the central components of diaphragmatic activation, but the available techniques of PS remain subject to some limitations. Transcutaneous PS is painful, and needle PS is potentially dangerous. Time-varying magnetic fields can stimulate nervous structures without pain and without adverse effects. In six subjects, we have studied cervical magnetic stimulation (CMS) as a method of PS. We have compared the stimulated Pdi (Pdistim) with the maximal Pdi obtained during static combined expulsive-Mueller maneuver (Pdimax) and with the Pdi generated during a sniff test (Pdisniff). CMS produced twitch Pdi averaging 33.4 +/- 9.7 cmH2O. Pdistim/Pdimax and Pdistim/Pdisniff were 24 +/- 6 and 41 +/- 14%, respectively. These values are comparable to those obtained in other studies with transcutaneous PS. They were highly reproducible in all the subjects. Electromyographic data provided evidence of bilateral maximal stimulation. CMS is a nonspecific method and may stimulate various nervous structures. However, diaphragmatic contraction was elicited by stimulation of the phrenic trunk, since the phrenicodiaphragmatic latencies (less than 7 ms) were in the range of values reported with direct stimulation of the trunk. Cocontraction of neck muscles, including the sternomastoid, was present, but its influence in the CMS-induced Pdi seems minimal. We conclude that magnetic stimulation is an easy, well-tolerated, reproducible safe, and valuable method to assess phrenic conduction and diaphragmatic twitch response.

Action Potentials↗
PubMed1988

[Peripheral neuropathies with neural vasculitis. Clinical and electrophysiological aspects of 33 cases].

Lesions of vasculitis of nerve were found in 33 of 140 patients hospitalized for peripheral neuropathy over a little less than 2 years, and in 113 specimens from neuromuscular biopsies. A first group of 7 patients had histological lesions suggestive of systemic necrotizing vasculitis (periarteritis nodosa in 4 cases and Churg and Strauss disease in 2 cases); the 7th patient was treated for myeloproliferative syndrome. The clinical and electromyographic signs were those of an axonal polyneuropathy which was improved by various treatments in 6 cases. A second group of 26 patients had histological lesions of vasculitis of nerve. Ten of these patients presented with single or multiple neuritis (of unknown origin in 5 cases), 11 with distal polyneuropathy (of unknown origin in 5 cases) and 3 with chronic polyradiculoneuritis; in 2 cases, clinical and electromyographic findings were in favour of an anterior horn lesion. The duration of the disease varied from 6 months to 10 years. The principal causes identified were connective tissue diseases, solid cancer or lymphoma and isolated gammapathy. Two patients with multiple neuritis recovered spontaneously. The finding of vasculitis of nerve at biopsy therefore is of unequivocal significance outside the better known but smaller group of systemic necrotizing vasculitis.

Adult↗
PubMed1988

A syndrome of REM and non-REM sleep reduction and lateral gaze paresis after medial tegmental pontine stroke. Computed tomographic scans and anatomical correlations in four patients.

A common pattern of reduction in both rapid eye movement and non-rapid eye movement sleep associated with various lateral gaze paralyses was present in four cases of brain-stem stroke. From computed tomographic scan data, clinical inferences, and, in two cases, neuropathologic sections, the common lesions were localized in the medial pontine tegmentum, ie, the inner part of the gigantocellular and pontis centralis caudalis nuclei. These data in humans were compared with lesions obtained experimentally in cats.

Adult↗
PubMed1988

[Sleep abnormalities and evoked potentials (VEP-BAER-SEP) in progressive supranuclear palsy].

Few physiological studies have been performed in PSP. We studied: sleep abnormalities in 36 h polygraphic recordings; changes of PEV after pattern-reversal stimulation, of BAER and of short latency SEP after stimulation of the median nerve. The population was for the 1st group: 18 patients with full typical symptomatology, for the 2nd group: 7 patients with likely diagnose of PSP and for the 3rd group: 10 normal subjects as control sample. All patients of the 1st group had sleep abnormalities: decrease of total sleep time; decrease of the percentage of REM sleep; morphological abnormalities (specially horizontal ocular square wave jerks). Detail is given of the repartition of such abnormalities in the two groups of patients. There is no correlation between sleep abnormalities and the natural history of the disease. The PEV and BAER, abnormalities were present in 50% of the cases. The PES were always normal. The help that can be provided by electrophysiological studies in the diagnose of PSP is discussed (particularly in group 2).

Aged↗
PubMed1988

[Sleep and dreams in Korsakoff's amnesia due to alcoholism].

Sleep and dreams in 15 chronic alcoholic patients with amnesia were compared with sleep and dreams of 15 age- and sex-adjusted normal subjects. The patients were subjected to psychological tests in order to determine their I.Q. and their memory disturbances. All subjects had two nights of polygraphic recordings; the first tested the natural sleep organization. During the second night, they were awakened 7 min after the onset of each REM sleep episode, and, at least once, 20 min after the onset of a stage II episode, in order to record on a tape their dream reports according to a standardized protocol. The sleep patterns of the amnesic patients did not show any significant alteration. However, after wakening during the night, patients exhibited a higher tendency to return to REMS than controls. There was still some dream activity in those patients, although noticeably less frequently, and their dream activity had a very poor verbal expression. However, there was no change with respect to the spatio-temporal organization, sensorial perceptions, motor activity and verbalizations during their dreams.

Adult↗
PubMed1988

Postradiation segmental myoclonus selectively inhibited by REM sleep (sleep-wake myoclonus).

A 46-year-old male patient was irradiated following left orchiectomy for seminoma. Three months after radiation, segmental myoclonus appeared involving all skeletal muscle groups up to the level of D10, the area of radiation. Urodynamic testing showed the presence of segmental myoclonus in the urethral sphincter. An around-the-clock 'continuous segmental myoclonus' during sleep and wakefulness with a frequency of 1 c/s and an amplitude of 400 microV selectively inhibited by REM sleep was not found in the literature. This continuous segmental myoclonus caused by a radiation myelopathy at D10-D11 was followed up for 2 years. It was partially controlled by carbamazepine.

Carbamazepine↗
PubMed1988

[The peripheral nervous system and HIV infection. 13 cases].

Disorders of the peripheral nervous system occur at all stages of HIV infection. From 13 patients referred for a peripheral neuropathy, 9 were known to be HIV seropositive and 4 were found to be seropositive. All were Caucasian males aged 27 to 58. Ten were homosexual, 2 were drug-addicts. Patients fell into several groups: the first group was made of 5 patients, 4 asymptomatic and 1 AIDS-related-complex (ARC), with an inflammatory demyelinating polyneuropathy, acute in 1 case and subacute in 4; the CSF showed pleiocytosis in all cases. Motor conduction nerve velocities were markedly reduced and motor distal latencies prolonged. Three patients recovered spontaneously, 1 responded to corticosteroids, 1 to plasmapheresis. In the second group, 4 patients, 1 asymptomatic and 3 ARC, had a distal symmetrical polyneuropathy; CSF was normal in 2 cases. Electrophysiological studies and nerve biopsies indicated a mixed axonal-demyelinating polyneuropathy. Three patients recovered spontaneously, 1 is unchanged. Among both groups, an infiltration of mononuclear cells was found on nerve biopsies in 4 cases. The third group was made of 3 patients with AIDS who presented with a painful sensory polyneuropathy involving the distal lower limbs. Electrophysiological and pathological study of the nerve indicated axonal degeneration. No cell infiltration was found. The last patient with AIDS had a progressive meningoradiculopathy. These 4 patients died within 6 months after the onset of the neuropathy. These findings are close to those previously reported, and confirm the wide spectrum of disorders of the peripheral nervous system associated to HIV infection.

Acquired Immunodeficiency Syndrome↗
PubMed1988

[Cervical magnetic stimulation. A new method of bilateral phrenic nerve stimulation for use in clinical practice].

The stimulation of the phrenic nerves in the neck is one of the techniques for the examination of diaphragmatic contractility. Current methods are restricted by their painful (transcutaneous stimulation) or even potentially dangerous nature (needle stimulation). We have tested both the feasibility and the validity of using magnetic stimulation (SMC) to stimulate the phrenic nerves. This method is painless and devoid of any side effects. Three healthy subjects have been studied using an EMG and transdiaphragmatic pressure measurements (Pdi.) Pdi values obtained by SMC (36.5 +/- 13.5 cm H2O) and their relation to maximal Pdi (22.6 +/- 7%) and to the Pdi at the time of maximal sniff-Pdi sniff (34.7 +/- 8%) were comparable to those values obtained using other methods and were reproducible. The preliminary results show that SMC is a technique for the study of the phrenic nerve and diaphragm which has the advantage of simplicity in use, is repeatable and is completely innocuous.

Adult↗
PubMed1988

[Progressive muscular atrophy localized in the hand. Monomelic form of motor neuron disease?].

Ten new cases of distal amyotrophy localized in an upper limb are reported. In all cases, patients were young males. The onset of the neurological impairment was always progressive during one to three years. The disease remained stable with a follow-up study of at least three years. Electrophysiological and neuroradiologic results were in keeping with an involvement of the anterior horn cell, in agreement with similar studies found in the literature. The relatively benign evolution of this syndrome, in regard to the usual prognosis of the other forms of motor neuron disease, especially amyotrophic lateral sclerosis, has to be outlined.

Adolescent↗