Abstract:
:The aim of this study was to develop a radiation-free method to measure gastric emptying. Such a method would be useful e.g. for patients who need repeated measurements and in pregnancy. Ferrimagnetic particles (gamma-Fe2O3), ingested within a solid test meal (pancakes), were magnetised by an applied magnetic field. After magnetisation, the remanent magnetic field was measured with fluxgate magnetometers outside the stomach (anterior and posterior). The intragastric contents was estimated from the strength of the remanent field. The procedure was repeated 18 times over a period of up to 2 h postprandially. The test meal was chosen to correspond to a radiolabelled test meal that had previously been used in a scintigraphic study with (other) healthy persons. In vivo measurements were carried out on 16 healthy male volunteers. The estimated retained magnetic tracer in the stomach after the 2 h measurement time was 31 +/- 12% (mean +/- SD) and the lag phase time was 31 +/- 11 min. The corresponding scintigraphic curve (from the previous study) from 16 males showed 40 +/- 14% retained isotope after 2 h. The early part of the mean emptying curve decreased slightly faster than the corresponding scintigraphic one, but the similarity of the two seems promising enough for further development of the present method.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
Forsman Mdoi
10.1007/BF02522849subject
Has Abstractpub_date
1998-01-01 00:00:00pages
2-6issue
1eissn
0140-0118issn
1741-0444journal_volume
36pub_type
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