Biomedical subjects

H Torp

Publications and source records attributed to H Torp.

3 recordsLinked to original sources

PubMed1991

Flow estimation using ultrasound imaging (color M-mode) and computer postprocessing.

We have developed a method to calculate flow noninvasively in blood vessels using color Motion-mode (M-mode) and computer postprocessing. The velocity of each point in the cross-sectional area of the vessel was found from the color M-mode recording by correcting for angle both distances and velocities and by assuming a symmetrical circular velocity field. Volume flow was then found by integrating the velocity field at 5-ms intervals through the cardiac cycle. In a cardiovascular hydromechanical model, a correlation of 0.99 and p value of less than 0.001 were found between estimated and measured flow in the model (n = 8). In 20 healthy individuals, we made 31 investigations in the common carotid (CCA), internal carotid (ICA), and external carotid (ECA) artery, comparing flow in the CCA with the added flow in the ICA and ECA. The values (CCA versus ICA + ECA) correlated with r = 0.91 and p less than 0.01. Repeated investigations (n = 8) in one individual gave flow estimates of 495 +/- 50 ml/min in the CCA, 304 +/- 45 ml/min in the ICA, and 165 +/- 37 ml/min in the ECA (means +/- SD). This article shows that this system can make accurate estimation of blood flow to the brain noninvasively.

Blood Flow Velocity↗

PubMed1990

Estimation of regurgitant volume and orifice in aortic regurgitation combining CW Doppler and parameter estimation in a Windkessel-like model.

A method for noninvasive estimation of regurgitant orifice and volume in aortic regurgitation is proposed and tested in anesthetized open chested pigs. The method can be used with noninvasive measurement of regurgitant jet velocity with continuous wave ultrasound Doppler measurements together with cuff measurements of systolic and diastolic systemic pressure in the arm. These measurements are then used for parameter estimation in a Windkessel-like model which include the regurgitant orifice as a parameter. The aortic volume compliance and the peripheral resistance are also included as parameters measurements in the open chest pigs are used. Electromagnetic flow measurements in the ascending aorta and pulmonary artery are used for control, and a correlation between regurgitant volume obtained from parameter estimation and electromagnetic flow measurements of 0.95 over a range from 2.1 to 17.8 mL is obtained.

Animals↗

PubMedDate not supplied

Clinical trial with a new substance (PLP 100-127) in order to asses therapeutic efficacy and dependence creating properties.

The objectives of the study have been to evaluate the therapeutic efficacy of PLP 100-127 (6-(4-methyl-l-piperazinyl) morphanthridin) on patients with moderate to severe insomnia, to evaluate safety and tolerance of the drug and to investigate whether or not the drug may have dependence producing properties through the possible development of mental and/or physical dependence. A clinical-therapeutical long-term comparsion as a double blind cross-over investigation between PLP 100-127 and nitrazepan is presented. 30 patients at Gaustad hospital, mainly long-term patients with the diagnosis of schizophrenia, were selected for the trial, which lasted for 38 weeks. There were 9 drop outs, mainly due to relapse of psychotic symptoms. PLP 100-127 seems to have a favorable effect on moderate and severe insomnia in patients suffering from severe mental diseases. It seems to be well tolerated in these groups of patients. No signs of dependence producing properties have been observed by the observation method here presented.

Adult↗