PubMed Health⌕ Search

Biomedical subjects

T Ledin

Publications and source records attributed to T Ledin.

18 recordsLinked to original sources
PubMed1992

Psychomotor recovery following propofol or isoflurane anaesthesia for day-care surgery.

A newly developed test for the assessment of psychomotor recovery--the perceptive accuracy test (PAT)--is described. Seventy-four subjects who performed the test though that it was easy to perform and some were motivated to try it on a number of occasions. Eight persons performed the test on different days and at different periods of time; the results were consistent and reproducible. Eight more persons were then asked to do the test 4 times at 15-min intervals; no 'learning' was seen with this test. A randomized, prospective study was then performed in two groups of 15 patients, undergoing arthroscopic procedures of the knee. Anaesthesia was induced with propofol and maintained with an infusion of propofol 12 mg/kg/h for the first 15 min, followed by 8 mg/kg/h subsequently in the propofol group. In the isoflurane group, anaesthesia was also induced with propofol, but isoflurane (0.5-2%) was used to maintain anaesthesia. Alfentanil was the analgesic used in both groups of patients. Results were compared with a third group of unanaesthetised controls, who were asked to perform psychomotor tests including choice reaction time and PAT at 30-min intervals for 2.5 h. There was a significant difference (P less than 0.01) in psychomotor recovery on the PAT-200 between the propofol group and control groups, but not in the isoflurane and control groups at 30 min. Both groups had returned to baseline values at 60 min in the PAT-60 and PAT-200. The choice reaction time showed no significant difference in either group 30 min after the anaesthetic.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Delayed neurological adaptation in infants delivered by elective cesarean section and the relation to catecholamine levels.

We have studied the effect of mode of delivery and catecholamine (CA) surge at birth on neurobehaviour 1, 2 and 5 days after birth. Fifteen full-term infants were delivered by elective cesarean section (CS) and 15 full-term control infants were born vaginally. Infants born after elective CS were less excitable and had significantly reduced number of optimal responses during the first 2 days after delivery, compared to the controls. On the 5th day no significant neurological differences were found between the groups. Adrenaline and noradrenaline (NA) in umbilical arterial plasma were analysed in all infants. The mean values of NA were lower in the CS infants as compared to the vaginally delivered infants. Statistically significant correlations were found between low CA levels and poor muscle tone and/or lower grade of excitability in the CS infants. These results suggest that the high CA surge at birth might be of importance for the neurological adaptation after birth.

Adaptation, Physiological↗
PubMed1991

Computerized dynamic posturography: a new method for the evaluation of postural stability following anaesthesia.

Dynamic posturography, a new method to study postural stability in humans, was performed in 11 healthy volunteers before administration of midazolam 0.1 mg/kg body weight i.v., and repeated subsequently at 45, 105 and 165 min. Results indicate that balance was affected significantly (P less than 0.008) up to 45 min after i.v. midazolam and did not return to control values until 105 min. The quantified version of the Romberg test performed with the eyes open or closed using the Equitest did not appear to be sensitive in detecting residual effects of midazolam on balance. We conclude that healthy, young persons should not be considered to have regained postural stability for up to 105 min after sedation with midazolam. Dynamic posturography appears to be a useful test in the objective assessment of balance disturbances.

Adult↗
PubMed1991

Correlation between dynamic posturography, clinical investigation, and neurography in patients with polyneuropathy.

Dynamic posturography (PG) is a new objective method to study functional performance in diseases affecting balance. It measures muscle response latencies and sway angles to standardized alterations of a moveable platform and moveable surroundings. Twenty-eight patients with polyneuropathy (PN) were studied by clinical investigation, vibrametry, neurography, and dynamic PG. The results of dynamic PG and vibrametry were compared with those of 29 healthy controls. In the patients with PN, clinical scores correlated to the latencies of the muscle response when the platform was suddenly moved forward, and to equilibrium performance (sway angles) in dynamic PG test conditions with eyes closed and the platform either stable or 'sway-referenced'. That is, the platform moves in response to the patient's anterior-posterior sway, creating a disturbed proprioceptive input to the brain. Clinical scores also correlated to the equilibrium performance when both platform and surroundings were sway-referenced. In conclusion dynamic PG, in addition to clinical investigations and neurophysiology, is a valuable and objective method for estimating the equilibrium performance in patients with PN.

Aged↗
PubMed1991

Effect of alcohol measured by dynamic posturography.

Thirteen healthy male volunteers aged 21-42 years (mean 27 years) were assessed by dynamic posturography before and after ingestion of alcohol. Each subject was given 0.6 g alcohol per kg body weight in fruit juice to be drunk within 10 min. Alcohol levels in blood samples at 15, 45 and 75 min after ingestion were assessed by gas chromatography. Posturographic measurements were conducted at 30 and 60 min after alcohol administration. Dynamic posturography comprises a sensory organization part in which the support surface and visual surround are either stable or referenced to the patient's sway and the test conditions are eyes open or eyes closed. In a movement coordination part the platform makes active movements. Alcohol levels were 0.40% (SD 0.14) after 45 min and 0.51% (SD 0.14) at 75 min. All subjects presented positional alcohol nystagmus and gaze nystagmus after 45 min. In the sensory organization part of the dynamic posturography in test conditions with eyes closed and the head in neutral position, both with stable (p less than 0.039) and sway-referenced platform (p less than 0.017), alcohol effects were found. In the test condition with sway referenced platform and stable visual surround the effect of alcohol was close to significance (p less than 0.069). When the head was tilted to either side, no effect of alcohol was detected, nor in the movement coordination test. It is concluded that dynamic posturography can detect the effect of alcohol on static and dynamic equilibrium. Test conditions with absent vision appear to be the most sensitive. The results in static conditions are well in agreement with previous studies; the findings under dynamic conditions are new.

Adult↗
PubMed1991

Dynamic posturography in cervical vertigo.

Cervical vertigo, the entity of neck disorder and associated vestibular symptoms, was investigated in 15 suspected subjects and results were compared with 15 age-matched controls. A modified dynamic posturography investigation with different head positions was used. Head position was recorded 3-dimensionally with electrogoniometry. Differences on a sway-referenced forceplate were found.

Adult↗
PubMed1991

Abstinent chronic alcoholics investigated by dynamic posturography, ocular smooth pursuit and visual suppression.

Eleven male chronic alcoholic volunteers aged 44-65 years (mean 57 years) were investigated by dynamic posturography, ocular smooth pursuit and visual suppression of the vestibulo-ocular reflex (VOR). Their drinking time ranged from 8-30 years (mean 20 years) and they had been abstinent for the last 1-20 years (mean 7 years). Ocular smooth pursuit showed abnormalities in 8/11. Abnormalities were found in 5/11 in the visual suppression of the VOR. The results of dynamic posturography tests were compared to an age-matched reference material. Dynamic posturography (EquiTest) comprises a sensory organization (SO) part in which the support surface and visual surround are either stable or referenced to the patient's sway, with eyes open or closed. In the SO part the chronic alcoholics had lower equilibrium scores in all test conditions, and the differences were significant in 4 tests out of 6. In a movement coordination part the platform makes active movements, the latencies to which were significantly prolonged in the 2 larger of the 3 translational amplitudes. Adaptation to repeated tilting of the platform was estimated to be pathological in 4/10, compared to none of the controls. The abnormal pattern found in dynamic posturography correlates well with the pathology in ocular smooth pursuit and visual suppression tests, suggested to be due to alcohol induced cerebellar lesions. It is concluded that dynamic posturography is a valuable test for assessing dysequilibrium in chronic alcoholics, even abstinent.

Adult↗
PubMed1991

Visual influence on postural reactions to sudden antero-posterior support surface movements.

Visual influence on force reactions to sudden antero-posterior (AP) translations of the support surface in 10 healthy men 23-58 years old (mean 36 years) were studied. Displacements ranged between 13 and 127 mm in both backwards and forwards directions. The experiment was conducted using a modified EquiTest dynamic posturography apparatus. An interactive menu-driven software enabled selection of a suitable translation pattern (i.e. square wave) in the AP direction. Data from four vertical force transducers were acquired and the position of centre of pressure (CP) in the AP direction was computed as function of time. The movement of CP in response to AP translation was characterized by the amplitude of the maximum CP displacement relative to the platform and the latency until maximum CP displacement occurred. The experiment unveiled that the latency to maximum CP displacement was larger for conditions with vision present. Furthermore, both the amplitude and latency to maximum CP deflection were increasing functions of translation amplitude. It is proposed that visual feedback influences the neural control on the postural reactions to sudden support surface translations. Absence of visual cues seems to cause a more rapid correction of the body position.

Adult↗
PubMed1990

Influence of elective cesarean section and breech delivery on neonatal neurological condition.

Fifty-three infants born after elective cesarean section (CS), and 28 infants born vaginally in breech presentation were compared with 45 full-term controls. A quantitative neurological assessment consisting of 31 items was performed on days 1, 2 and 5 after birth. A tonus score, an excitability score and the number of optimal responses were calculated. A follow-up examination was done at 6 months of age, with a standardized neurological and developmental examination. The results showed that infants born after elective CS in both vertex and breech presentation had significantly reduced number of optimal responses during the first five days after delivery, compared to controls. They were more hypotonic and less excitable than the control infants during the first 2 days. There were no significant differences in neurological results between infants born after CS with general or epidural anaesthesia. The infants born in vaginal breech presentation showed no differences neurologically as compared to the controls on the first day. On days 2 and 5, however, they were less excitable and showed a reduced number of optimal responses. There were few differences in neurological condition between the infants born after elective CS and the infants born vaginally in breech presentation. Growth, psychomotor development and neurological status at 6 months did not differ significantly between the three groups. Our findings indicate that infants born after elective CS and vaginal breech presentation have a delayed neurological adaptation during their first days of life. These differences did not affect the physical well-being of the infants, which showed normal growth, neurology and development at the follow-up at 6 months of age.

Apgar Score↗
PubMed1990

Squamous cell carcinoma of the oral cavity. A review of 176 cases with application of malignancy grading and DNA measurements.

This retrospective study comprised 176 patients with squamous cell carcinoma of the oral cavity treated at The Linköping University Hospital over a 19-year period. Clinical parameters, microscopic malignancy grading (according to Jakobsson et al. and Glanz and Eichhorn), DNA cytofluorometry, analysis of therapeutic modalities and statistics regarding survival and prognosis are reported. The mean age was 70 years with a male: female ratio of 1.3:1 One hundred and four patients had T1 or T2 tumours and 109 an N0 neck. Cervical lymph node metastases were more frequent in patients with larger tumours (T3 + T4) than in those with smaller (T1 + T2) (P less than 0.01), in tumours with a high malignancy grading compared to those with a low (P less than 0.05) and in DNA non-diploid tumours compared to diploid ones (P less than 0.001). The aneuploid tumours responded better to preoperative radiotherapy than did diploid (P less than 0.01) or polyploid (P less than 0.05) tumours. Eighty-nine per cent of the recurrences occurred within 1 year of initial therapy. Secondary treatment was successful in 15 of 37 (41%) patients in whom the tumour recurred either at the primary site or in regional lymph nodes, but only in 1 of 8 (12%) with recurrences in both locations. Surgery alone or combined with radiotherapy resulted in equivalent survival rates for tumours in stages I and II. In advanced stages combined radiotherapy and surgery gave better survival figures than either modality alone (P less than 0.01; Kaplan-Meier). The presence of lymph node metastases (P less than 0.001), tumour size (P less than 0.01) and tumour ploidy (P less than 0.005) were the only clinical and histological parameters that significantly influenced survival (Cox regression analysis). Twenty-four patients developed a secondary primary malignancy; 21 of these were located in the aerodigestive tract.

Aged↗
PubMed1990

Otoneurological findings in workers exposed to styrene.

An otoneurological test battery was administered to 18 workers with long-term exposure (6-15 years) to styrene at levels well below the current Swedish limit (110 mg/m3). The results were compared with those of a reference group. Disturbances were found in the central auditory pathways of seven workers. Tests reflecting central processing of impulses from different sensory equilibrium organs were abnormal for 16 workers. The most relevant tests seemed to be static posturography and the rotatory visual suppression test. In the posturography the styrene group had a significantly larger sway area than the reference group. In the visual suppression test, the styrene workers displayed a significantly poorer ability to suppress vestibular nystagmus than the reference group. It was concluded that styrene exposure in industrial environments at moderate or low levels causes central nervous system disturbances which are not always diagnosable with psychometric tests but can be apparent in special otoneurological tests.

Adult↗
PubMed1989

The ratio of pepsinogen A to pepsinogen C: a sensitive test for atrophic gastritis.

To diagnose fundic atrophic (type A) gastritis as part of the clinical investigation of various diseases or for epidemiologic purposes, a simple and reliable diagnostic test would be of great value. We studied circulating levels of pepsinogen A (PGA) and pepsinogen C (PGC) in 179 patients with fundic atrophic gastritis, 29 unselected patients with gastric adenocarcinoma, 15 totally gastrectomized patients, and 50 gastroscopically examined normal controls. Of 147 patients with severe atrophic gastritis, 42 (29%) had serum PGA and 22 (15%) serum PGC values within the range of those in totally gastrectomized patients. The most sensitive test for fundic atrophic gastritis was the PGA/PGC ratio in serum, the sensitivity and specificity being 99% and 94%, respectively (discrimination limit, 5.5). Correspondingly, the positive predictive value was 98%, and the negative predictive value 98%. Of 29 unselected patients with gastric adenocarcinoma 22 (76%) had serum PGA/PGC values lower than the discrimination limit for atrophic gastritis. We conclude that the relatively simple analysis of PGA and PGC in serum is a powerful test for fundic atrophic gastritis with several potential areas of application.

Adenocarcinoma↗
PubMed1989

Isometric muscle force and anthropometric values in normal children aged between 3.5 and 15 years.

Isometric muscle force was measured in 217 normal children aged 3.5-15 years. The standard error of a single determination made by the same observer was ca. 9% of the muscle force. When two measurements were made by different observers the standard error of the difference was estimated at ca. 17%. Reference values for isometric force are given for boys and girls separately. With regard to 7 of the 10 muscle groups tested the force was significantly greater in boys than in girls as early as at ca. 10 years of age. Age and weight were the most important predictors of muscle force.

Adolescent↗
PubMedDate not supplied

Chronic toxic encephalopathy investigated using dynamic posturography.

Seven male patients previously exposed to industrial solvents and diagnosed with chronic toxic encephalopathy (aged 38 to 69 years; mean age, 56 years) were investigated by dynamic posturography and compared with healthy, age-matched male control patients. Dynamic posturography comprises two phases: a sensory organization (SO) phase, in which the support surface and visual surround are either stable or referenced to the patient's sway, with eyes open or closed, and a movement coordination (MC) phase, in which the platform makes active movements. In SO testing, the patient group showed significantly impaired equilibrium performance compared with the control group in most test conditions. The MC test revealed no differences between groups. A relationship was found between the equilibrium score resulting from SO testing with stable support and visual surround and the sway area of the confidence ellipse elicited 3 years previously by static posturography with eyes open. We conclude that patients with chronic toxic encephalopathy have impaired equilibrium, as demonstrated by dynamic posturography testing.

Adult↗
PubMedDate not supplied

Posturography findings in workers exposed to industrial solvents.

Postural control was investigated by static posturography in 18 workers exposed to industrial solvents, 9 patients with psycho-organic syndrome due to industrial solvent exposure, and 52 controls. Both groups of exposed subjects showed larger sway areas with eyes open as well as closed, compared with the controls. No differences were found in the Romberg quotient (the relationship between sway areas with eyes closed/open). The correlation between static posturography and the otoneurological test battery was positive for the visual suppression test in the styrene group. In the industrial solvent group no significant correlations were found. The visual suppression test and some auditory tests were pathological in the exposed groups. The otoneurological test battery--especially the visual suppression test and static posturography--seems to contribute in the assessment of solvent related CNS lesions.

Adult↗
PubMedDate not supplied

Dynamic posturography in assessment of polyneuropathic disease.

Twenty-eight patients with polyneuropathy aged 49-82 years (mean 67 years) were assessed by dynamic posturography. The patient group was compared to a control group comprising 29 healthy controls aged 70 through 75 years (mean 73 years). The dynamic posturography method comprises a sensory organization part in which the platform and visual surround are either stable or referenced to the patient's sway; furthermore, the eyes are open or closed. In a movement coordination part the platform makes active movements. In the sensory organization part of the dynamic posturography the patient group showed significantly lower equilibrium performance compared to the control group in the test conditions with absent vision, sway-referenced surrounding, and, finally, sway referenced platform and surrounding. In these conditions the influx of somatosensory information is of paramount importance for stable posture. In the movement coordination test, the patient group showed prolonged muscular response latencies in both forward and backward platform perturbations compared to the control group. It is concluded that dynamic posturography is a valuable diagnostic tool in assessment of the dynamic equilibrium performance in patients with polyneuropathy.

Aged↗
PubMedDate not supplied

Effects of balance training in elderly evaluated by clinical tests and dynamic posturography.

All persons aged 70 through 75 years (N = 457) in a Swedish community were invited to participate in a 9 week balance training study. Out of 55 interested subjects, 15 were chosen at random for a study group; 15 matched controls were also selected. Before and after the investigation period the balance function was assessed by clinical balance tests and dynamic posturography. In the clinical balance tests, the training group significantly improved their balance standing on one leg with eyes closed as well as standing on one leg while shaking the head; they also walked 15 m back and forth faster. In the dynamic posturography the training group significantly improved their equilibrium scores in the 3 most difficult test conditions. The results of the control group were unchanged except for one test condition in the dynamic posturography. The differences in one-leg standing with head shaking, walking 2 x 15 m, and the equilibrium score using sway-referenced platform in dynamic posturography were proved to be attributable to the training. The first investigation in all 29 subjects formed normative dynamic posturography data for the age group 70 through 75 years. The normative posturographic data of this age group differed from previously obtained data in the age groups 20 through 59 and 60 through 69 years. It is concluded that elderly may improve their balance by regular balance training exercises for as short a period as 9 weeks. This might prove to be of great value in improving balance and thereby preventing accidental falls and subsequent fractures in elderly.

Aged↗