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T Amundsen

Publications and source records attributed to T Amundsen.

31 records · Page 2Linked to original sources
PubMed1995

An automated C4b binding protein assay compared with an electroimmunoassay in a clinical material.

We have evaluated an automated, simplified, turbidimetric method for the measurement of the C4b binding protein (C4bBP). A comparison with a manually performed electroimmunoassay in plasma samples referred for coagulation analysis (n = 80) revealed a correlation coefficient of 0.88. Lipaemic plasma is not suitable for analysis, whereas moderately haemolytic or icteric plasma may be used with the present method. In young and middle-aged patients (n = 33) investigated 3 or more months after an episode with thrombosis of unknown reason, the mean C4bBP concentration was not significantly different from the mean found in healthy controls (n = 38). This result is in accordance with the hypothesis that C4bBP is an acute phase reactant. The results indicate that the turbidimetric assay may replace the electroimmunoassay in clinical work.

Adult↗
PubMed1995

Clinical results after percutaneous automated lumbar nucleotomy. A follow-up study.

This study was carried out in order to assess the clinical results after percutaneous automated nucleotomy with regard to predictive factors for the outcome. Selection criteria included patients with predominance of low-back pain, diffuse posterior disk bulges and concomitant spinal stenosis who are not normally accepted for nucleotomy. In all, 142 patients were treated. The overall success rate after an average observation time of 21 months was 56%. The results were not influenced by whether a diffuse posterior bulge or a focal hernia had been treated or not (p = 0.449). Spinal stenosis (p = 0.043) and disk space narrowing exceeding 25% of the expected width (p = 0.017) were associated with a poor outcome. By excluding these categories and patients with symptoms from more than one disk level, the success rate rose to 70%. With this selection, the results were equally good in patients with predominantly low-back pain compared to those with predominantly sciatica (p = 0.490).

Adult↗
PubMed1995

CT-diskography, diskomanometry and MR imaging as predictors of the outcome of lumbar percutaneous automated nucleotomy.

PURPOSE: This prospective study was performed to assess whether CT-diskography (CT-D), diskomanometry (DMM) including recording of the pain response, or the MR signal intensity of the disks are reliable predictors of the outcome of nucleotomy. MATERIAL AND METHODS: Ninety-one patients, 44 females and 47 males aged 18-68 years (mean 37.4) treated at 99 disk levels were included. All had plain CT, MR imaging, CT-D and DMM performed prior to automated percutaneous nucleotomy with the Nucleotomy R system. RESULTS: Sixty-nine (76%) of the patients responded well to treatment within 3 months. Due to recurrences, the success rate at 1 year was reduced to 65%. Except for better results following nucleotomy in patients with similar and identical pain as the presenting complaint provoked at diskography, no association was demonstrated between diskographic parameters, or loss of signal on MR, and the outcome. Better results were also seen in patients with a short history of disk disease, but not in patients with predominantly sciatica and focal hernias compared to those with predominantly low-back pain and diffuse posterior bulges. CONCLUSION: The results do not justify routine use of diskography prior to nucleotomy in patients with pathologic disks demonstrated by noninvasive methods and localizing sciatic pain.

Adolescent↗
PubMed1994

[Percutaneous automated lumbar nucleotomy. Patient selection, practical performance and clinical results].

Percutaneous nucleotomy is designed to treat small and medium-sized contained disk hernias. It is offered to patients who have not responded to conservative treatment for three months or more. The nucleotomy procedure is well tolerated by a majority of patients and the rate of complications is low. The patients can be treated as out-patients. Among a total material of 130 patients, a primary good response to the treatment was observed in 81 (62%). However, owing to recurrencies the success rate had fallen to 52% at 12-39 months (mean 22 months) after nucleotomy. In selected patients with symptoms from one disk level only, and with no evidence of spinal stenosis, or of osteophyte formation or a narrowing of the disk space by more than 25%, the results were better. Here the success rate was 61% (70% in males and 50% in females).

Adult↗
PubMed1994

CT changes after lumbar percutaneous automated nucleotomy.

In order to assess changes occurring in disk hernias and disk spaces following percutaneous nucleotomy a follow-up CT was carried out an average of 6 months after treatment of 69 disks in 60 patients. Forty-three of the disks were also reexamined at an average of 11 months after the first follow-up. Twenty-seven percent of the hernias were reduced in size at the first follow-up. Fourteen percent were reduced and 7% had increased between the first and second follow-ups. The medium-sized and large hernias were more frequently reduced compared to the smaller ones. Reduction of the disk space was found in 29% of the cases at first follow-up. An additional 24% were reduced between the first and second follow-ups. No association was demonstrated between change in size of the herniation or disk space and clinical outcome or amount of nucleus material removed at nucleotomy.

Adult↗
PubMed1993

Lumbar percutaneous automated nucleotomy. Technique, patient selection and preliminary results.

The purpose of this study was to evaluate 2 years' experience with percutaneous automated nucleotomy. Adult patients with small to medium sized disk hernias corresponding to clinical symptoms, and without evidence of free fragments or stenosis were treated on an outpatient basis. All patients had sciatica and conservative treatment had failed for at least 3 months. Using the Nucleotome R system, access to the disk was achieved in all but 6 of 172 disks in 152 patients. Degenerative disk disease or pain was the reason for technical failures. Four other procedures were discontinued because of pain and moderate hemorrhage. Except for one case of diskitis, no serious complications occurred. Of the patients in a prospective study, 63 had a follow-up period of 4 months or more. The overall clinical success rate was 62%, and was not significantly influenced by patient sex or age, duration of symptoms, level treated, disk degeneration or amount of nucleus material removed. The results are promising; however, this study indicates a need for refined patient selection in order to decrease the number of failures.

Adolescent↗
PubMed1991

Regional lung water measurements with PET: accuracy, reproducibility, and linearity.

We evaluated the accuracy, reproducibility, and linearity of lung water concentration (LWC) measurements using positron emission tomography (PET) in anesthetized supine dogs. First, we evaluated whether errors in attenuation correction, which might occur during the development of pulmonary edema, significantly affect LWC and pulmonary blood flow (PBF) measurements obtained with PET. In 10 animals, PET scans of LWC and PBF were obtained before and after oleic acid induced lung injury. Changes in LWC and PBF after injury were underestimated by 12%-25% if the postinjury LWC scan was reconstructed using attenuation data obtained prior to injury, before lung density had changed, instead of attenuation data obtained after lung injury. Next, in four other dogs, we did not administer oleic acid, but instead instilled progressive amounts of autologous plasma into the left caudal lobe and obtained LWC measurements after each. Changes in LWC were linearly related to the amount of plasma instilled (r = 0.99). The average coefficient of variation for LWC in the control right lobe was 4 +/- 2% and the average percent change between measurements was 1.5% +/- 5.8%. The correlation of regional LWC determined gravimetrically after the last scan, when corrected for differences in regional lung density, with LWC determined by PET, was excellent (r = 0.92). We conclude that when the correct attenuation scan is used for emission scan reconstruction. PET measurements of LWC are accurate, linear, and reproducible.

Animals↗
PubMed1990

Comparison between theophylline and an adenosine non-blocking xanthine in acute asthma.

Enprofylline, a drug without adenosine antagonism and theophylline, a potent adenosine antagonist, were compared, double-blind, randomized, in acute asthma (n = 33). The drugs were given intravenously as loading over 10 min followed by maintenance infusion for 24 h. Mean final plasma levels were very high with enprofylline (14 mg.l), and larger than calculated with theophylline (16 mg.l). Seven patients had maximum levels of enprofylline ranging between 16 and 42 mg.l. Extreme plasma levels of enprofylline were not associated with any theophylline-like central nervous system excitatory effects related to seizure-inducing ability. Some irregularities in the heart rhythm did not raise clinical problems and no significant difference between enprofylline and theophylline was recorded. At 1 h patients on enprofylline (mean plasma level: 5.7 mg.l) and theophylline (12.2 mg.l) had improved their peak expiratory flow rates by 31% and 15% (p less than 0.05), respectively. The improvement in lung function after 24 hours did not differ between treatments suggesting that the high levels of enprofylline were supramaximal for its anti-asthma effects in this situation. In conclusion, with enprofylline it is demonstrated that an adenosine non-blocking xanthine derivative may lack CNS-excitatory effects, but be more potent than theophylline in the treatment of acute asthma.

Acute Disease↗
PubMed1986

Cardiac dysfunction during acute lung injury induced by oleic acid in dogs.

Circulatory abnormalities are common during the adult respiratory distress syndrome and contribute importantly to the high mortality seen with this illness, but what causes them is not well characterized. Oleic acid-induced acute lung injury is an experimental model of the human syndrome in which hemodynamic changes are also common. To characterize a possible link between lung injury and cardiac dysfunction in this model, we evaluated cardiac function in mongrel dogs after oleic acid administration. Stroke volume index decreased, the radionuclide ventriculographically determined ejection fraction decreased, and end-diastolic volume increased after oleic acid. These results suggested a decrease in myocardial contractility, a conclusion confirmed when other experiments demonstrated a consistent rightward displacement of the end-systolic pressure-diameter relationship after oleic acid. Histologic examination of the myocardium showed little evidence of vascular injury, and myocardial tissue wet-to-dry weight ratios were normal. Thus, although the pulmonary effects of oleic acid are due to microvascular injury, similar mechanisms are not responsible for the depression in myocardial contractility.

Acute Disease↗