Biomedical subjects

B Lantz

Publications and source records attributed to B Lantz.

At least 37 records · Page 2Linked to original sources

PubMed1977

Management of septicemia and early death in acute leukemia.

The frequency of fever days was measured in 67 patients with acute leukemia in the initial phase until remission was obtained or the patient died. A total of 3411 hospital days were studied. Three antibiotic schedules were examined between 1970 and 1975. There were 50% fever days when penicillin and streptomycin were combined as initial antibiotics, 37% when cephalosporin and gentamycin were used, and 31% when, in addition, semi-isolation was used prophylactically and granulocytes were given in a therapeutic attempt (0.05 greater than p greater than 0.01). The corresponding frequencies of early death were 9/21 (43%), 6/23 (26%) and 5/23 (22%). Early death occurred on an average 14, 23 and 21 days after admission. The frequencies of remission (complete and partial) were 8/21 (38%), 12/23 (52%), and 13/23 (57%). A randomized subgroup (12 patients) with intestinal sterilization was studied separately. It had 28% fever days, which is significantly less (p less than 0.01) than in the 13 patients given the same systemic antibiotics without intestinal sterilization. Fever was significantly lower (0.05 greater than p greater than 0.01) on the day after a series of granulocyte transfusions than before, although only 10(9) granulocytes were given. However, this fever reduction may have been due to concomitant antibiotics.

Acute Disease↗

PubMed1976

Autopsy findings in leukaemia.

Out of 38 leukaemic cases only 16 had extensive leukaemic infiltration at death. 15 patients had slight or moderate and 7 no infiltration at all. 12 of the 15, and 5 of the 7 died with septicaemia. The latter patients must have died of complications rather than of the leukaemia itself. Although it has been possible to reduce the incidence of septicaemia during life, terminal septicaemia does not yet seem to be preventable. Septicaemia was revealed at autopsy in 27 of 38 patients; 25 of these also had clinical signs of septicaemia before death. Necrotizing gastrointestinal lesions may cause endogenous infection. In the present material, almost every second patient had fungal septicaemia. Out of 7 patients having oral candidiasis in vivo 5 had systemic candidiasis at autopsy, but only half of the patients with systemic candidiasis had visible oral growth. Modern treatment of leukaemia seems to be able to prevent intracranial haemorrhage in 90% of the cases. On the other hand, vacuolization of muscle and liver tissue was a frequent finding in leukaemia. It is suggested as being caused by fatty degeneration. Vacuolization of myocardial cells was found in 7 out of 13 cases. Among these 7, 4 had had intermittent hypokalaemia.

Acute Disease↗

PubMed1975

Contrast formation in fluoroscopic videodensitometry. III. Relation between roentgen tube potential and exposure rate to produce constant video level.

The exposure rate required to produce a prescribed value of the video level in a vidicon television chain during fluoroscopy was measured for water layers and copper filters of varying thickness. The reduction of the patient exposure rate was found to be so large that, in spite of a reduction of the iodine extinction to 20 to 50 per cent of the value at 40 to 50 kV, examinations of the circulatory system are recommended to be performed at 100 kV with slight copper filtering.

Absorptiometry, Photon↗

PubMed1975

Spectral variation of the conversion factor of an image intensifier.

The conversion factor of the image intensifier Sirecon duplex 25/15 was investigated by means of a videodensitometer for varying values of the tube potential and varying filtering of the radiation. It was found that the conversion factor can be increased by Cu filtering. By analysis of the measurement data, the spectral variation of the conversion factor was determined. The conversion factor has a maximum for 60 keV photons and falls rapidly for photons of energy below 45 keV. By the method described, the spectral response function of an image intensifier can be determined experimentally without the use of a spectrometer.

Absorptiometry, Photon↗

PubMed1975

Speed of response of a 50 Hz and a 250 Hz TV system.

The speed of response of a newly developed 250 Hz high image rate Plumbicon television system was compared with the ordinary 50 Hz Vidicon and Plumbicon television systems. The high time resolution of the 250 Hz system, almost five times that of the 50 Hz Vidicon and three times that of the 50 Hz Plumbicon system, makes it well adapted for videodensitometry particularly if the velocity of the contrast bolus or the pulse profile within the circulation are to be evaluated.

Absorptiometry, Photon↗

PubMed1975

Relative flow measured by roentgen videodensitometry in hydrodynamic model.

The behaviour of injected iodine contrast medium in a pulsative hydrodynamic model was recorded on videotape in television fluoroscopy and measured by roentgen videodensitometry. By a simple relationship between the integrated densitometric area, the amount of injected contrast medium, and the flow at the site of the injection, it was possible to compare the flow in two different cross-sections of the circulatory system with high accuracy.

Absorptiometry, Photon↗

PubMed1975

Three-dimensional reconstruction of the human heart by video technique.

Three-dimensional reconstruction of different plastic phantoms, organic material and beating human heart was achieved by utilizing a standard roentgen-television system. In continuous stabilized fluoroscopy the television images of the object obtained from different projections were digitized in real time and computerized for reconstruction. Despite a cone beam being used, the spatial resolution seems to be quite adequate for evaluation of gross anatomic structures like the cardiac walls without enhancement by contrast medium.

Absorptiometry, Photon↗

PubMed1973