Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics最新文献

{"title":"Validation of a method of treating menorrhagia by endometrial ablation.","authors":"J H Phipps,&nbsp;T Smith,&nbsp;P Dymek,&nbsp;R Hesp,&nbsp;B V Lewis","doi":"10.1088/0143-0815/13/3/007","DOIUrl":"https://doi.org/10.1088/0143-0815/13/3/007","url":null,"abstract":"<p><p>Menstrual blood loss was measured by intravenous injection of radioactive iron (59Fe) and whole-body counting in 19 women complaining of menorrhagia due to dysfunctional bleeding. Fifteen patients were then treated by radiofrequency endometrial ablation, after which blood loss was re-measured. The majority of the patients were bleeding excessively before treatment (mean 281 (SD 156) ml per cycle averaged over two cycles, range 49-665 ml, n = 19). In the 15 treated patients, average blood loss was reduced to 52 (SD 39) ml per cycle and the mean reduction in blood loss was highly significant (P < 0.001). These quantitative data correlate well with the patients' subjective reports.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 3","pages":"273-80"},"PeriodicalIF":0.0,"publicationDate":"1992-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/3/007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12595111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A miniaturised force-torque sensor with six degrees of freedom for dental measurements.","authors":"J Planert,&nbsp;H Modler,&nbsp;K Lüdecke,&nbsp;M Eger","doi":"10.1088/0143-0815/13/3/003","DOIUrl":"https://doi.org/10.1088/0143-0815/13/3/003","url":null,"abstract":"<p><p>Force-torque sensor systems capable of simultaneously measuring all six spatial degrees of freedom on solid bodies are not very widespread in the medical field, particularly because of the hitherto unacceptably large external dimensions. A sensor based on the strain gauge technique has been developed with a diameter of only 32.5 mm and height of 29 mm. The miniaturised supporting framework for the strain gauges has been cast in a single piece from a wax-plastic model by the one-way mould principle. A sensitivity of 10 mN with an upper limit of 50 N is attained.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 3","pages":"241-8"},"PeriodicalIF":0.0,"publicationDate":"1992-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/3/003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12595107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of an oxygen multiwire surface electrode for the direct measurement of the distribution of alveolar PO2 at different inspired oxygen concentrations.","authors":"J Höper,&nbsp;L Plasswilm","doi":"10.1088/0143-0815/13/3/006","DOIUrl":"https://doi.org/10.1088/0143-0815/13/3/006","url":null,"abstract":"<p><p>Experiments were performed in six anaesthetised, mechanically ventilated rabbits. After thoracotomy, a multiwire surface PO2 electrode was placed at the pleural surface by means of a special holder. The local distribution of PO2 was investigated at different values of inspired oxygen concentration (FIO2). The data were analysed in order to establish (a) whether the PO2 values measured at the lung surface reflect intra-alveolar PO2 and (b) that the distribution of these values represent real physiological differences between alveoli. The mean PO2 values were related to the calculated mean alveolar PO2 (PAO2) values (r = 0.97) indicating that it is possible to study PAO2 by local measurements. It can therefore be concluded that the technique used allows the study of the influence of different FIO2 values on the distribution of PAO2. Each local PAO2 value is the result of the corresponding local ventilation/perfusion ratio (VA/Q) therefore the distribution of PAO2 values represents the distribution of VA/Q. An increasing FIO2 causes an increasing heterogeneity of PAO2 and thus VA/Q leading to a concomitant increase in the alveolo-arterial oxygen difference. At the moment it is not possible to decide if this heterogeneity is primarily caused by heterogeneities in perfusion or ventilation. The results could throw fresh light on the effect of different ventilation procedures.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 3","pages":"263-71"},"PeriodicalIF":0.0,"publicationDate":"1992-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/3/006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12595109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetocardiography.","authors":"Y Nakaya,&nbsp;H Mori","doi":"10.1088/0143-0815/13/3/001","DOIUrl":"https://doi.org/10.1088/0143-0815/13/3/001","url":null,"abstract":"","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 3","pages":"191-229"},"PeriodicalIF":0.0,"publicationDate":"1992-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/3/001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12595847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A miniature silicon diode matrix detector for in vivo measurement of 133Xe disappearance following local tissue injection.","authors":"K Bendtsen,&nbsp;J H Svendsen,&nbsp;H B Rasmussen,&nbsp;Y Damgaard,&nbsp;S Haunsø,&nbsp;P Sejrsen,&nbsp;J Bojsen","doi":"10.1088/0143-0815/13/3/002","DOIUrl":"https://doi.org/10.1088/0143-0815/13/3/002","url":null,"abstract":"<p><p>A variety of biological processes can be studied from the washout of compounds labelled with a gamma emitter. Conventional systems for measurement of gamma radiation can detect count rates at both the low and high energy range of the indicator in question, 133Xe. However, silicon (Si) photodiodes have the capability of measuring the lowest energies (25-40 keV) of gamma and x-ray emitters with sufficient efficiency when applied on the skin surface and close to the indicator depot. The purpose of the present study was firstly to evaluate a portable Si photodiode matrix detector system, composed of 16 photodiodes, for in vivo measurement of disappearance rate constants of 133Xe following injection into subcutaneous (SC) or skeletal muscle (SM) tissues as compared with a stationary sodium iodide single crystal detector. Secondly, from these results, to evaluate the contribution from intra-tissue indicator diffusion and indicate means of avoiding influence from local diffusion in the washout curve of 133Xe. From the recorded 133Xe distribution in the depot proper, Si photodiodes in the matrix were selected for calculation of the washout. The Si matrix detector was reliable with a constant linearity and sensitivity within the range 20-38 degrees C and calibrated to +/- 1% between diodes. The in vivo investigations comprised two SC injections on humans with four measuring periods for comparison, and four SC and five SM injections on dogs, resulting in eight and five measuring periods for comparison. Only when the results obtained from the Si photodiodes at the position just above the count rate maximum were selected, was the contribution from diffusion significant. The ability to detect geometry changes is advantageous in studies with potential motion artefacts, such as during exercise.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 3","pages":"231-40"},"PeriodicalIF":0.0,"publicationDate":"1992-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/3/002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12595848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conductance studies of rat renal medulla for rapid estimation of extracellular electrolyte concentration.","authors":"L Dobrowolski,&nbsp;J Sadowski,&nbsp;E Kompanowska-Jezierska","doi":"10.1088/0143-0815/13/3/005","DOIUrl":"https://doi.org/10.1088/0143-0815/13/3/005","url":null,"abstract":"<p><p>A method is described for estimation of tissue extracellular electrolytes in fresh excised rat renal medulla on the basis of its electrical conductance. The inner medulla was placed between two standard flat electrodes and the conductance was measured at a frequency of 3.5 kHz. The data were corrected for the surface area and thickness of the tissue fragment. The standard conductance so determined clearly correlated with total electrolyte concentration, and Na+ and 2(Na+ + K+) concentrations in the whole tissue (r = 0.84, 0.81 and 0.77, respectively; P < 0.001). The method enables a rapid and simple estimation of medullary extracellular electrolytes, a variable that is physiologically more meaningful than whole tissue electrolyte concentration.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 3","pages":"257-62"},"PeriodicalIF":0.0,"publicationDate":"1992-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/3/005","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12595110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single breath measurement of pulmonary blood flow in man: the causes of variability.","authors":"R H Hooper,&nbsp;P J Franks","doi":"10.1088/0143-0815/13/2/006","DOIUrl":"https://doi.org/10.1088/0143-0815/13/2/006","url":null,"abstract":"<p><p>Theoretically, pulmonary blood flow can be measured by the uptake of a 'soluble' gas (e.g. freon-22) compared with an 'insoluble' gas (e.g. argon). As with all indirect methods, a number of uncertainties exist. Inhalation of a freon-22 and argon mixture (3.5%, 10%, 35% O2 balance N2) was made, with a subsequent, slow steady exhalation. The complete manoeuvre is termed the single breath technique (SBT). The repeatability of the SBT was assessed over four repeat measurements at rest, the mean difference between paired measurements lying in the range -0.09 to 0.04 l min-1, excluding the first trial measurements. Various features of the SBT were investigated to assess their influence on the reliability of the technique. It is shown: that the initial volume inhaled should be close to vital capacity; that a brief period of apnoea greater than 9 s following inhalation is necessary; that the subsequent exhalation should be about 10 l min-1; and that difficulties associated with recirculation of freon-22 are not encountered, presumably due to its wide distribution in body water. Under these highly controlled circumstances the technique is reliable.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 2","pages":"139-49"},"PeriodicalIF":0.0,"publicationDate":"1992-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/2/006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12668664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The development of the low profile Liverpool shear transducer.","authors":"P Laing,&nbsp;H Deogan,&nbsp;D Cogley,&nbsp;S Crerand,&nbsp;P Hammond,&nbsp;L Klenerman","doi":"10.1088/0143-0815/13/2/002","DOIUrl":"https://doi.org/10.1088/0143-0815/13/2/002","url":null,"abstract":"<p><p>The development of a shear transducer, small enough to be worn comfortably under a normal foot, is described, along with a microcomputer controlled data logger. Walks up to 8 s can be recorded and the information downloaded to any IBM compatible computer. Software then allows easy analysis of the peak shear stresses. Calibration curves show the transducers to have a linear response up to 35N and preliminary data from the measurement of shear stresses under the normal foot, and their relationship to vertical pressures, is presented. A patent application (number 9109463.1) has been filed for the device in the United Kingdom.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 2","pages":"115-24"},"PeriodicalIF":0.0,"publicationDate":"1992-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/2/002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12669443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A prototype instrument combining laser Doppler flowmetry and reflection pulse oximetry.","authors":"G Dougherty,&nbsp;N J Barnett,&nbsp;S J Pettinger","doi":"10.1088/0143-0815/13/2/001","DOIUrl":"https://doi.org/10.1088/0143-0815/13/2/001","url":null,"abstract":"<p><p>A prototype instrument has been developed to combine the monitoring techniques of laser Doppler flowmetry and reflection pulse oximetry, both of which depend on laser light backscattered from the skin tissue. Simultaneous and continuous measurements of both microvascular blood flow and blood oxygen saturation were obtained from the same measurement site. Oximetry readings from the combined instrument were calibrated using a model system, and compared with those determined using a Nellcor N-100 transmission pulse oximeter in a limited clinical study: they showed a variability of +4% and read low by 5-10%.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 2","pages":"105-14"},"PeriodicalIF":0.0,"publicationDate":"1992-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/2/001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12669440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement and prediction of drug solvent losses by evaporation from a jet nebuliser.","authors":"S W Smye,&nbsp;M I Jollie,&nbsp;H Cunliffe,&nbsp;J M Littlewood","doi":"10.1088/0143-0815/13/2/004","DOIUrl":"https://doi.org/10.1088/0143-0815/13/2/004","url":null,"abstract":"<p><p>The evaporative losses of solvent (water) from a commercial jet nebuliser (Unineb, Unimed Ltd) were estimated and found to be approximately 14% of total nebuliser output. A simple analysis of the nebulisation process then enabled the amount of the drug colomycin released as potentially respirable aerosol to be predicted from measurements of the total nebulisation time. Good agreement was found between the predicted (P) and measured (M) values such that P = 1.07 M (r2 = 0.98). The analysis also indicates that the proportion of the drug released as aerosol will increase as nebulisation proceeds provided nebuliser output is continuous and that for a given initial mass of drug a larger amount of drug is released as an aerosol if the volume of administration used in the nebuliser is as large as possible.</p>","PeriodicalId":77070,"journal":{"name":"Clinical physics and physiological measurement : an official journal of the Hospital Physicists' Association, Deutsche Gesellschaft fur Medizinische Physik and the European Federation of Organisations for Medical Physics","volume":"13 2","pages":"129-34"},"PeriodicalIF":0.0,"publicationDate":"1992-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1088/0143-0815/13/2/004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"12668660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}