Biomedical subjects

D Romary

Publications and source records attributed to D Romary.

3 recordsLinked to original sources

PubMed1985

Application of image processing techniques to gamma-angiography.

Different image processing techniques have been tested and compared on data derived from gamma-angiography images to detect the boundary of the left ventricle. The method involves a preprocessing step, followed by the edge detection itself. The best preprocessing is a nonlinear "variant" filtering, where each pixel is replaced by the average of the 3 X 3 neighborhood having the smallest variance. The edge detector giving the best contour is a Sobel operator. A second-order high-pass Butterworth filter also provides a good segmentation.

Computers↗

PubMed1984

Radionuclide assessment of cardiac function. Pre-operative evaluation of patients with abdominal aortic occlusive disease undergoing aortobifemoral bypass grafting.

Pre-operative radionuclide angiography, a non-invasive technique for evaluating ventricular function, was performed on 34 consecutive patients undergoing aortobifemoral bypass grafting for abdominal aortic occlusive disease, to determine whether pre-existing coronary artery disease causes significant modification of cardiac function. Patients were divided into two groups according to medical history. Group I had 23 patients with no symptoms of coronary artery disease and Group II had 11 patients, six with previous myocardial infarction and five with angina pectoris. There was a significant difference in left ventricular ejection fraction and in cardiac output between these two groups. A flow-directed pulmonary artery catheter was inserted in eight patients in Group II who had an ejection fraction less than 50% and a nitroglycerin infusion was used in six cases to maintain pulmonary capillary wedge pressure below 20 mmHg. In the other patients, only central venous pressure was monitored. All patients had uneventful operative courses. It is concluded that left ventricular function is significantly altered in patients with symptoms of both abdominal aortic occlusive disease and coronary artery disease. By contrast, cardiac function is normal in patients free from symptoms of coronary artery disease, and central venous pressure monitoring seems sufficient in the management of these patients during aortobifemoral bypass grafting.

Aged↗

PubMed1983

[Comparative study of gastric emptying of digestible and nondigestible solids in normal man and duodenal ulcer patients].

Few studies have compared the gastric emptying of digestible and non-digestible solids in man. In 9 normal subjects and 16 duodenal ulcer patients, we measured simultaneously and during 3 h, the gastric emptying of: (a) radioopaque pellets (n = 100; volume = 30 mm3) ingested with an ordinary meal (450 kcal, 500 ml) and counted on X-ray series; and (b) digestible solids of the meal (99mtechnetium tagged egg white) detected by an isotopic method. Gastric emptying of liquids (labelled with 113mindium DTPA) was also determined. In normal subjects, emptying rates of the pellets was 5 +/- 2 p. 100 per hour while that of digestible solids was 29 +/- 1 p. 100 per hour (P less than 0.01). No correlation was evidenced between the emptying rates of either kind of solids. Emptying of liquids was faster than that of both digestible solids and pellets. Similar results were obtained in duodenal ulcer patients; no significant difference was found between patients and normal subjects for the three meal phases tested. These results are consistent with the hypothesis that digestible solids are retained in stomach until they are ground, and show that inert particles do not always reflect the gastric emptying of natural solids of the meal.

Adult↗