technetium-tc-99m-sulfur-colloid and octanoic-acid

To develop a simple method for simultaneous solid and liquid gastric emptying assessment using a dual isotope labelled breath test.. 13 patients were given 100 g ground beef labelled with 25 MBq (99m)Tc sulphur colloid and 74 KBq (14)C octanoic acid, and 150 ml 10% glucose drink labelled with 8 MBq (67)Ga citrate and 150 mg (13)C acetate. 10 normal volunteers were given the same test meals but labelled with (14)C and (13)C only. Breath was collected at baseline and regularly for 4 hours. The (14)CO(2) and (13)CO(2) activity was measured with liquid scintillation counting and mass spectroscopy. The times to maximum (14)CO(2) and (13)CO(2), were determined. Comparison was made between times to maximum (14)CO(2) with scintigraphic retention of (99m)Tc at 100 minutes and times to maximum (13)CO(2) with the scintigraphic half-clearance time of (67)Ga.. For the solid meal, the times to maximum (14)CO(2) were: 60-120 minutes in the 8 patients with normal gastric emptying of (99m)Tc; 75-145 minutes for the 10 healthy volunteers; 75-180 minutes for the remaining 5 patients with abnormal gastric emptying of (99m)Tc. There was a weak but significant correlation (r = 0.56, p < 0.025) between the time to maximum (14)CO(2) and gastric retention of (99m)Tc at 100 minutes. For the liquid meal, times to maximum (13)CO(2) were: 20-35 minutes for the 4 with normal gastric emptying of (67)Ga; 15-40 minutes for the 10 healthy volunteers; 20-75 minutes for the remaining 9 patients with abnormal gastric emptying of (67)Ga. There was a strong and significant correlation (r = 0.88, p < 0.005) between times to maximum (13)CO(2) and gastric half-clearance time of (67)Ga.. Breath tests utilising test meals labelled with *C isotopes are valid alternatives to scintigraphic studies using (99m)Tc and (67)Ga for the simultaneous assessment of gastric emptying of solids and liquids.

Topics: Acetates; Administration, Oral; Adult; Age Factors; Aged; Breath Tests; Caprylates; Carbon Radioisotopes; Citrates; Esophageal Motility Disorders; Female; Gallium; Gastric Emptying; Humans; Male; Middle Aged; Radionuclide Imaging; Radiopharmaceuticals; Reproducibility of Results; Sensitivity and Specificity; Sex Factors; Stomach; Technetium Tc 99m Sulfur Colloid

Disordered gastric motility may be a significant factor in the pathogenesis of many equine conditions. Although tests for liquid phase emptying rate have been validated in the horse, there are no effective tests for solid phase emptying measurement that can be performed routinely in the field.. The objective of this study was the assessment of a novel stable isotope technique, the 13C-octane acid breath test (13C-OABT), for the measurement of gastric emptying of solid ingesta, by direct comparison with the optimum method of gastric scintigraphy.. To facilitate dual measurement of gastric emptying, a test meal was used containing baked egg yolk labelled with both 13C-octanoic acid and 99mtechnetium sulphur colloid. Simultaneous, serial lateral gastric scintigraphs and expiratory breath samples were obtained in 12 healthy horses after voluntary ingestion of the test meal. Analysis of breath 13CO2:12CO2 ratio was performed by continuous flow isotope ratio mass spectrometry. Power regression was used to determine the gastric emptying coefficient, the gastric half-emptying time (t 1/2) and duration of the lag phase (tlag).. Significant correlations (P < 0.001) were found between the 2 techniques for measurement of both t 1/2 and tlag. In addition, scintigraphic left t 1/2 was correlated significantly to breath test gastric emptying coefficient (P < 0.001).. It was concluded that the 13C-octanoic acid breath test is a reliable diagnostic procedure to measure gastric emptying rate of solids in the horse.. Being safe, noninvasive and easy to perform, this test has potential value as both sensitive diagnostic modality and humane research tool for motility studies.

Topics: Animals; Breath Tests; Caprylates; Carbon Dioxide; Carbon Isotopes; Female; Gastric Emptying; Horse Diseases; Horses; Male; Radionuclide Imaging; Sensitivity and Specificity; Stomach; Technetium Tc 99m Sulfur Colloid; Time Factors

Current methods for measuring gastric emptying by breath test require sampling over several hours and are too inaccurate for clinical use. The aim of this study was to develop an office-based method for measuring gastric emptying of solids in patients with diabetes using a [13C]octanoic acid breath test.. In 22 symptomatic diabetic patients (17 insulin-dependent diabetes, 5 non-insulin-dependent diabetes) and 6 controls, we simultaneously measured gastric emptying of an egg meal (420 kcal) by scintigraphy and [13C]octanoic acid breath test. Conventional (nonlinear) methods for scintigraphic and [13C]octanoic acid breath test emptying and generalized linear regression method to predict scintigraphic half-life (t(1/2)) using four breath samples obtained during the first 3 h.. Despite 8 h of breath sampling, the t(1/2) estimate using the conventional method was markedly different from the scintigraphic value (delta t(1/2): median, 113 min; range, 19-282 min). The generalized linear model (using samples at baseline, 30, and 120 or 150 min) yielded predicted scintigraphic tLAG and t(1/2) that were more accurate than the conventional method; mean standard deviations of differences were 16 and 27 min, respectively. Breath test correctly assessed normal or prolonged emptying in 21 of 22 patients.. The [13C]octanoic acid breath test can be simplified to measure gastric tLAG and t(1/2) and can be expected to correctly identify normal t(1/2) in symptomatic diabetics. Further refinement of the model will need to include studies of patients with markedly delayed t(1/2).

Topics: Adult; Aged; Ambulatory Care; Breath Tests; Caprylates; Carbon Radioisotopes; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Female; Gastric Emptying; Gastroparesis; Humans; Male; Middle Aged; Predictive Value of Tests; Radionuclide Imaging; Reference Values; Technetium Tc 99m Sulfur Colloid