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M Buxeda

Publications and source records attributed to M Buxeda.

10 recordsLinked to original sources

Evaluation of Aution Max AX-4280 automated urine test-strip analyser.

Aution Max AX-4280, an automated urine test-strip analyser, was evaluated in three centres. Method comparison, imprecision, carry-over, linearity, detection limit and drift studies were performed for glucose, protein, blood and leukocytes using Uriflet S 9UB strips. These strips enable measurement of pH, glucose, protein, blood, leukocytes, ketones, bilirubin, urobilinogen and nitrite. Specific gravity is determined by the refractive index method. Within-run and between-day imprecision, assessed using pooled urines and quality control materials, were good. No drift over 24 h or sample carry-over was observed. Method comparison with quantitative methods for glucose, protein and specific gravity yielded good correlations. Ascorbate negatively interfered with haemoglobin, glucose and nitrite measurements. Acetylsalicylic acid lowered pH, the effect being greatest when protein was absent. During the assessment period no malfunction or breakdown was reported. The Aution Max is easy to use and needs minimal maintenance.

Ascorbic Acid↗

Stress and rest myocardial SPET quantification with 201Tl and 99Tcm-tetrofosmin: a comparison.

99Tcm-tetrofosmin is a new myocardial perfusion agent that has excellent physical and pharmacokinetic characteristics for performing tomographic myocardial perfusion studies. The aim of this study was to compare the behaviour of 99Tcm-tetrofosmin and 201Tl in the assessment of ischaemia and viability in patients with previous myocardial infarction. Twenty consecutive patients who had suffered infarction and been referred for assessment of ischaemia and myocardial viability were enrolled into the study. Each patient underwent two stress tests performed no more than 10 days apart, one with a 201Tl exercise-reinjection-redistribution method and one with a 99Tcm-tetrofosmin short protocol (exercise-rest). The results were quantified using polar maps to represent images for stress, rest and reversibility. The post-stress images showed there was a slight tendency to overestimate defect size with 99Tcm-tetrofosmin in the lateral region (P < 0.006). We found no significant differences between the two tracers when comparing reversibility. The same defect size at rest were obtained when the maps for 201Tl with uptake of 50% were compared with those for 99Tcm-tetrofosmin with uptake of 45%. Agreement between the two agents for assessment of viability was 93%. We conclude that the quantitative assessment of myocardial ischaemia and uptake of 99Tcm-tetrofosmin at rest are comparable to those obtained with 201Tl in patients who have suffered myocardial infarction.

Adult↗

[ST segment elevation during exercise test and perfusion scintigraphy in patients without infarction].

BACKGROUND: The features of perfusion scintigraphy in patients who show exercise-induced ST-segment elevation in the absence of previous infarction have been assessed in only a few reports. Therefore, we have evaluated our experience in a wide review of exercise 201-thallium scintigraphies. METHODS: 16,620 exercise 201-thallium scintigraphies, carried out between 1986 and 1993, have been retrospectively reviewed. Fourteen patients (0.8/1000) without previous infarction who were evaluated for chest pain showed ST-segment elevation. In all patients coronary arteriography was also available. RESULTS: Five patients were free from significant coronary artery stenoses, 6 had one-vessel disease, 2 had two-vessel disease, and the remaining patient had three-vessel disease. In 8 patients ST-segment elevation (up to 3-24 mm) was inferior, in 5 anterior and in 1 lateral. The radionuclide was injected during ST-segment elevation in 10 cases and before such elevation (which developed in the postexercise phase) in 4. In 3 out of these 4, which had angiographically normal coronary arteries, the scintigraphy was negative. In all cases where thallium-201 was injected during ST elevation, severe perfusion defects were detected corresponding to the localization of ST elevation. In the 4 patients with critical coronary stenoses, thallium-201 redistribution after 3 hours was partial. CONCLUSIONS: In patients without previous infarction and with exercise-induced ST-segment elevation, very severe perfusion defects are detected when the radionuclide has been injected during the crisis. Thallium-201 redistribution after 3 hours was not total in patients with fixed critical stenoses. When radionuclide injection preceded the crisis, the result of the scintigraphy was in agreement with the coronary anatomy.

Adult↗

Transplant renography: 99m-Tc-DTPA versus 99m-Tc-MAG3. A preliminary note.

99mTc-MAG3 has been proposed as a replacement for both 131I-hippuran and 99mTc-DTPA on clinical grounds. We undertook a prospective preliminary study to ascertain whether 99mTc-MAG3 works better than 99mTc-DTPA in the follow up of renal transplant recipients. Seventeen patients (21 renograms each MAG3 and DTPA) were studied, together, with a reference group of 10 patients in whom MAG3 and Hippuran clearance rates were determined simultaneously. As expected, 99mTc-MAG3 analog images were excellent and 99mTcMAG3 clearance correlated very well with 131I-hippuran clearance (r = 0.978). MAG3 values were 60% of hippuran values. However, when the corresponding renographic and perfusion findings were faced with different diagnostic challenges, such as post transplant renal failure and rejection, 99mTc MAG3 did not differ from 99mTc-DTPA in a significant way. 99mTc-DTPA was superior to 99mtc-MAG3 in one case of rejection.

Adult↗