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P Ingrand

Publications and source records attributed to P Ingrand.

86 records · Page 5Linked to original sources

Microcomputer analysis of three-channel Lissajous' trajectory of auditory brainstem evoked potentials.

A software package for the IBM PC computer is presented to facilitate the analysis of three-channel Lissajous' trajectories (3CLT) of auditory brainstem potentials. The program deals with 4-channel numeric or ASCII files, including three orthogonal X, Y, Z channels and standard vertex-mastoid on the stimulated side. The 3CLT analysis program implements standard measurements of peak latencies, voltage amplitude and curvature plots computed from the three orthogonal channels, interactive three-dimensional rotations of the trajectory and planar segment analysis. Parameter estimates of the best-fit plane are computed for any part of the trajectory limited by two latency cursors. Results are displayed and stored in a table including segment bounds and duration, sight vector orientation, plane equation parameters and adjustment criteria.

Evoked Potentials, Auditory↗

[Articular manifestations in Wegener's disease. Report of 13 cases].

Seventeen cases of Wegener's granulomatosis have been reviewed in search of articular involvement. Articular symptoms were present in 13 cases (76 p. cent), and were inaugural in 9 cases (53 p. cent). Six of these patients experienced arthralgias, which were most often migratory, and were inaugural in 3 cases. Seven patients had arthritides, which were inaugural in 6 cases; they were fixed and additive in 6 of these 7 cases, making up a distal polyarthritis in 3 patients, and an oligoarthritis in the 3 other ones; they were transient and migratory in 1 case. The 3 cases of distal polyarthritis were inaugural and fulfilled the ARA criteria for rheumatoid arthritis; two of them were accompanied by nodules which were quite identical to rheumatoid ones. There was no axial involvement. Joint involvement was not destructive and had a favourable course under disease treatment. Myalgias were present in 3 cases, one of which simulated Horton's disease. Biological manifestations chiefly consisted of marked inflammatory changes. Antineutrophil cytoplasm antibodies were present in 11 out of 16 patients in whom they were searched; among 6 of these patients who had active disease, they were present in 5. The antibody level decreased as treatment reduced disease activity and suppressed joint involvement. Joint involvement in Wegener's granulomatosis seems to be the inconstant hallmark of disease activity. It requires no specific treatment.

Adult↗

[Value of nifedipine in respiratory failure related to obstructive chronic bronchitis during treatment over 6 months].

We studied the simultaneous effects of nifedipine on the pulmonary circulation and blood gases in 12 patients with pulmonary hypertension secondary to obstructive chronic bronchitis. Measurements were carried out at rest and during stress, initially then one hour after administration of 20 mg of nifedipine sublingually. They were repeated in a similar fashion after a 6-month treatment with 60 mg/day (group II) (30 mg/day in case of intolerance) (group I). The results of the immediate effect of nifedipine are in favor of a passive pulmonary vasodilatation secondary to the systemic vasodilatation. After six months of treatment, the pulmonary vasodilatation persists, but is associated with a decreased motor pressure indicating a more specific and more active pulmonary vasodilating effect of long-term nifedipine, especially during stress; this results in the improvement of the performance of the right ventricle without harmful effect on the blood gases. However, these results should be interpreted with caution on account of the small number of patients, the large interindividual variations and the absence of a reference population.

Administration, Sublingual↗

Effects of electrolytic lesions of the superior olivary complex and trapezoid body on brainstem auditory-evoked potentials in the guinea pig. II. Three-channel Lissajous' trajectory analysis.

Brainstem auditory-evoked potentials (BAEP) were studied both with vertex (positive) - tragus (negative) derivation and three-channel Lissajous' trajectory (3-CLT) planar analysis in guinea pigs (GP) after destruction of the ipsilateral superior olivary complex (SOC) (6 GP), contralateral SOC (8 GP) referred to the stimulation side, and trapezoid body (TB) in the sagittal line (8 GP). The size of the lesion was evaluated on histological examination. The right ear was locally destroyed with aminoside instillation. The left ear was stimulated with unfiltered clicks and tone bursts of different frequencies at 100 dB SPL. Three questions were the basis of this study: (i) What are the effects of brainstem lesions on 3-CLT? (ii) Is there a relationship between planar segments and underlying sources? (iii) What is the generator of planar segment C (P3) in GP? 3-CLT analysis was made on plane A (corresponding to P1 on a vertex-tragus channel), plane B (N1-P2) and plane C (P3.) Plane C disappeared after TB lesions and remained after ipsi- and contralateral SOC destructions. However, plane C disappeared after extensive lesions to the contralateral SOC affecting the TB. Planes A and B were always observed whatever the lesion, with sometimes a modification of their orientation. A localized brainstem lesion induced a local modification of the three-dimensional trajectory. These data are in agreement with the assumption that some planes of 3-CLT reflect the activity of underlying generators. However, the loop which contains the planar segment is a better indicator of the global electrical activity of the source. Plane C (P3) would have a contralateral source which is probably not the SOC but the afferent curved fibers of the TB close to the contralateral SOC.

Animals↗

[Characteristics of 3-dimensional representations of brain stem auditory evoked potentials].

The three dimensional Lissajous curves (3 CLT) of orthogonal derivation (vertex Z+; throat Z-) (left mastoïd Y+; right mastoïd Y-) (nasion X+; neck X-) were calculated and recorded by a computer. 3-D curves were computed with an apparent rotation around the vertical axis Z. Through successive exhibition of the "virtual" plots, the observer will remark a spatial representation of the 3-D curve. As in vectocardiography, a careful scrutiny of these curves displays different planar segments. Of the different coordinates specifying planar segments position in space: azimuth and elevation are the most reproducible. This paper describes the graphic and automatic measurements submitted and gives the results obtained from subjects with normal hearing.

Brain Stem↗

Three-dimensional curves: main parameters of brainstem auditory-evoked responses in the normal subject.

Brainstem evoked potentials (BER) have been studied in three dimensions (3D). It was necessary to record simultaneously three orthogonal derivations in the three spatial axes. The 3D curves obtained were formed by successive uncompletely locked loops which correspond with the first five waves of BER. Planar segment could be identified in the 3D curves; planes were defined by geometrical parameters, following standard analytic geometry. The 3D curves appeared to be symmetrical after right and left stimulation, and were almost completely flattened around the anteroposterior axis after binaural stimulation. This flattening was not observed in the case of multiple sclerosis.

Acoustic Stimulation↗

Wave III of brain-stem auditory evoked potentials analysed both with 3-channel Lissajous' trajectory and dipole localization method.

Wave III of the BAEP was analysed both with 3-channel Lissajous' trajectory (3-CLT) and a dipole localization method. The experiments were performed on 5 normally hearing subjects. The dipole analysis used an iterative algorithm assuming a spherical head model and homogeneous media. 3-CLT planar analysis was performed with a laboratory system. The parameters of plane C (azimuth and elevation) corresponding to wave III and those of the equivalent dipole showed a similar orientation of the plane and the dipole. This result is in agreement with previous investigations and confirms the interest of 3-CLT in far-field analysis and, at the same time, validates the dipole localization model used in this study, at least for BAEP analysis.

Adult↗

Event-related auditory evoked potentials and multiple sclerosis.

Long latency event-related auditory evoked potentials, particularly the P300 wave, constitute an objective electrophysiological index of cognitive function. For this reason, these potentials have been studied in a series of 101 patients with multiple sclerosis (MS), classified according to McAlpine's criteria into definite, probable and possible cases. The patients were also classified as depressed or non-depressed according to the DSM-III and Research Diagnostic Criteria. They were also subjected to a battery of psychometric tests. In the patient population the N200 and P300 latencies were increased, as were the P200 latencies, when compared with a control population. This electrophysiological pattern had previously been observed in other conditions characterised by subcortical lesions. Partial correlations (at constant disease duration) between the disability score and the cognitive deficit were found to be significant. Patients with an increased P300 latency had a greater disability and the P300 latency was significantly correlated with the duration of the illness. The N200 and P300 latencies were increased in depressed MS subjects, but this increase did not reach the level of significance. Depression was more frequent in the more severely handicapped patients. This suggests that the origin of the depression seen in multiple sclerosis is only partly organic, and that it is one of the factors contributing to the subcortical cognitive deficit in multiple sclerosis. Progressive forms of the disease exhibited the most profound cognitive deficit, and the most marked increase in P300 latency.

Acoustic Stimulation↗

Reliability of the pretransfusion bedside compatibility test: association with transfusion practice and training.

BACKGROUND: The utility of a pretransfusion bedside blood compatibility protocol to decrease immunohemolytic accidents has been questioned for years. STUDY DESIGN AND METHODS: The reliability of a standard bedside ABO compatibility test was evaluated with a stratified random sample of 48 nurses who performed agglutination testing by using Bristol cards, interpreted compatibility, and decided whether to transfuse red cells for 12 randomly and blindly selected donor-and-recipient blood sample pairs. An expert judged technical performance and the interpretation of each card. RESULTS: Erroneous decisions occurred in 18.2 percent of 576 tests, including 12 decisions to transfuse incompatible blood. Errors involved both testing protocols and the interpretation of compatibility. Anti-A and anti-B were detected with 92.8-percent sensitivity and 95.9-percent specificity. The expert judged 17.7 percent of tests to be technically inadequate, most often because of the application of excess blood to the card and a lack of rotation of the card. Testing errors (16.1% of tests) were significantly linked to infrequent transfusion activity by the nursing service, inexperience, and insufficient training. Compatibility misinterpretation occurred in 14.6 percent of the tests and was significantly linked to the nurses' infrequent transfusion activity, inexperience, insufficient training, lack of practical experience, and confusion regarding the use of ABO-compatible but not identical blood. CONCLUSION: Bedside pretransfusion compatibility determination should not be considered a reliable supplemental safety procedure in the hands of inexperienced and insufficiently trained operators.

ABO Blood-Group System↗

Functional recovery and social outcome after cerebral infarction in young adults.

This study was designed to assess the return to work, the poststroke depression and the quality of life after a cerebral infarction in young adults and was conducted on 71 consecutive young patients (aged 15-45 years) affected by a cerebral infarct who were hospitalized for the first time and discharged at least 1 year before the study. Data about risk factors, etiology, side and territory of stroke, social characteristics of the patient (age, sex, profession, educational level, family situation), poststroke seizures, recurrent stroke, other vascular events, and deaths were collected. Neurological deficits were graded with the National Institutes of Health (NIH) Stroke Scale. Poststroke depression (PSD) was quantified using the DSM-IIIR criteria and the Montgomery Asberg Depression Rating Scale. Outcomes were rated with the Ranking Scale, the Barthel Index and the Glasgow Outcome Scale. Quality of life was assessed with the Sickness Impact Profile. Follow-up information was obtained by interview and neurological examination. Follow-up information was obtained in 65 patients at a mean of 31.7 +/- 13.0 (range 12-59) months, as 2 patients died and 4 were lost to follow-up and were thus excluded from this study. Poststroke seizures occurred in 7 patients (10.8%) and recurrent strokes in 4 patients (6.2%), but none were fatal. The outcome after stroke among survivors was usually good, since more than two-thirds of the patients (69.8%) reported no problem, 11.1% moderate handicap and one-fifth major handicap. Forty-six patients (73%) returned to work: the time period ranging from several days after stroke to 40 months, with a mean of 8 months. However, adjustments in their occupation were necessary for 12 patients (26.1%). PSD was common, since 48.31% of the patients were classified as depressed. PSD was associated with the localization of the infarct (carotid territory), a severe disability, a bad general outcome, and an absence of return to work. Their opinion about their quality of life was negative among approximately 30% of the patients, especially in emotional and alertness behaviors. social interaction, recreation and pastimes. The general outcome after cerebral infarct in young adults is usually good. However, the risk of a PSD is high, and only half of the patients had returned to their previous work. A remaining psychosocial handicap and depression of sexual activity impaired the quality of life. In multivariate analysis, a low NIH score at admission is a significant predictor for return to work, the absence of PSD, and a good quality of life.

Adolescent↗

[Aniseikonia. A clinical study of 51 unilateral pseudophakic patients and practical applications].

The subjective aniseiconia was measured with spatial eiconometer on 51 isometropic and unilateral pseudophakic patients in relation with the post-operative anisometropia. The median value of subjective aniseiconia is 2-3% for anisometropia minus or equal to 5 diopters, without statistic correlation, related to a probably "sensorial brain adaptation". So error of intra-ocular lens power calculation less than 7.5 diopters may be accepted.

Aged↗

[Radiological consequences of lumbar disk surgery. Evaluation by MRI after 3 months].

Radiologic effects of the surgery for lumbar disc herniation: a study with MRI at the end of the third post-operative month. The results of patients operated for lumbar disc herniation are good in 83%, fair in 10% and poor in 7. The poor results are considered to be the consequence of post operative fibrosis. A prospective study in 67 patients has been performed to study the post operative appearance of the operated lumbar spine, three months after surgery. 45 days after surgery the recovery of patients was assessed by the score of Staufer and Coventry and patients were entered in the study independently of their clinical state. The MRI was performed at the end of the third month postoperatively and patient recovery assessed according to the score of Senegas and Lavignolle. All the clinical and radiologic data were statistically analysed... the chi-square test, a p. value less than 0.05 was considered statistically non significant. The correlation between the clinical recovery and the MRI was realized.

Adult↗

[Analysis of the monthly incidence of cutaneous leishmaniasis in Ceará (Brazil) between 1986 and 1990].

To determine the value of an epidemiological surveillance system, we evaluated the incidence rate and trends of American Cutaneous Leishmaniasis (ACL) in three health districts of Ceara state, Brazil. We used a retrospective time series analysis of ACL notifications in Ceara state between 1986 and 1990. The trend of this endemic/epidemic disease was analysed by using three types of modeling on the moving average graph: a linear, linear periodic and non linear periodic model. The study samples consisted of the 14,615 cases of ACL notified in Ceara state between 1986 and 1990. Males accounted for 54% of cases. Age was between 1 month and 19 years in 42% of cases. Most cases (81%) were diagnosed on clinical grounds only. After calculation of the moving average and application of a linear regression model to these means, the trend analysis revealed that 1) there was a significant trend towards an increase in two of the three health districts, with correlation coefficients of 0.31 and 0.49 (Student's t test = 2.24 and 3.88) and a significant trend towards a decrease in the remaining district (correlation coefficient = 0.51, t = 4.1). The linear periodic model showed a cyclic representation with a 36-month period and a base of 241. The non linear periodic model showed a cycle of 32 months and a base of 241, and was a better representation of the disease variations. Despite the limited study period, it appears that the 32-month cycle could be attributed to meteorological conditions. Field studies are underway to determine the precise causes of this periodicity.

Adolescent↗