Volumetric quantification of coronary artery calcifications using dual-slice spiral CT scanner: improved reproducibility of measurements with 180 degrees linear interpolation algorithm.

Purpose: The purpose of this work was to determine the reproducibility of coronary total calcium score (TCS) with dual-slice helical CT and compare three acquisition protocols.

Method: Fifty patients (59 +/- 10 years old) underwent dual-slice helical CT (collimation = 2 x 2.5 mm) and coronary angiography.

Broadband ultrasound attenuation at the calcaneus measured using a new contact ultrasound unit.

We evaluated a new contact ultrasound device, developed and manufactured in France, for measuring broadband ultrasound attenuation at the calcaneus. We first studied the influence on measurement results of a number of parameters including the nature of the coupling agent, heel position, transducer temperature, and foot vasodilation. We then determined the reproducibility of the measurements (2.

Limited activity of mini-dose interferon alpha-2a in the treatment of myelodysplastic syndrome.

Impairment in marrow function often characterizes the evolution of myelodysplastic syndrome. As a differentiating agent, interferon alpha 2a (INF alpha) has been shown to be active in the correction of cytopenias related to myelodysplastic syndromes (MDS). We report the clinical course of 9 patients with MDS treated with low-dose subcutaneous INF alpha (1 x 10(6), 3 times per week).

Scintigraphic Study of Local Flux and Osmotic Pressure Distributions in Ultrafiltration of Blood and Plasma.

We have investigated the spatial variation of local protein concentration and filtration flux by a scintigraphic technique in the ultrafiltration of bovine albumin solutions and blood. The feed was mixed with (99m)Tc albumin macroaggregates and circulated through a polysulfone 30,000 MWCO hollow fiber filter placed in the field of a gamma-camera. Concentration profiles c(b) (x) were reconstructed from scintigraphic images and the local ultrafiltration flux was calculated by differentiating c(b) (x) and using mass conservation.

Detection of prosthetic valve thrombosis using 111indium platelet imaging.

The diagnosis of prosthetic valve thrombosis (PVT) may be difficult in cases without valve obstruction. The aim of this study was to evaluate the diagnostic accuracy of 111indium-labelled autologous platelet imaging in the detection of PVT. We studied 41 patients with 45 prostheses, mechanical (37) or biological (8), in the mitral (26) or aortic (19) site.

Adequate preservation of right ventricular function after coronary sinus cardioplegia. A clinical study.

Whether retrograde coronary sinus cardioplegia adequately preserves right ventricular (RV) function is still a point of concern. Using technetium Tc 99m-labeled red blood cells, we assessed global and segmental RV function by first-pass and gated blood-pool radionuclide angiocardiography before and within 24 hours after aortic valve replacement in 14 consecutive patients (age, 58 +/- 5 years; mean +/- SEM). Coronary sinus cardioplegia was given in a multidose fashion at a flow rate of 50-70 ml/min through a balloon-tipped catheter, with the inflated balloon kept seated around the intra-atrial rim of the coronary sinus orifice.

Radionuclide exploration of dialysis amyloidosis: preliminary experience.

The noninvasive diagnosis of amyloid arthropathy in dialysis patients is still uncertain. Therefore, we investigated the potential diagnostic value of the 99mTc-methylene diphosphonate scan in seven long-term hemodialysis patients suffering from chronic joint pain who had biopsy-proven osteoarticular amyloidosis of the recently discovered beta 2-microglobulin (beta 2-M) type. In six, but in none of five control patients on short-term hemodialysis, increased tracer uptake was found at the site of one or several articular and/or periarticular regions.

Left ventricular global and regional function during lumbar epidural anesthesia in patients with and without angina pectoris. Influence of volume loading.

The influence of lumbar epidural anesthesia without cardiac sympathectomy on global and regional left ventricular function was investigated prior to surgery in eight normal subjects (group 1) and in ten patients suffering from stable mild effort-related angina (group 2). In both groups, epidural blockade was performed with 10 ml 0.5% plain bupivacaine.

[Value of computed medical imaging in the surveillance of neo-adjuvant chemotherapy of osteogenic osteosarcoma in children and adolescents. 51 patients seen from 1984 to 1986].

The value of quantitative bone scintigraphy, digitised angiography, CT scanning and magnetic resonance imaging in the follow-up of neo-adjuvant chemotherapy for osteogenic osteosarcoma was assessed in 51 patients between 1984 and 1986. Bone scintigraphy was a very sensitive method of detecting bone metastases but of limited value in assessing the response to preoperative chemotherapy. CT scanning was very useful in small and medium sized tumours with predominantly non-calcific involvement of the soft tissue.

Response of left ventricular ejection fraction to recovery from general anesthesia: measurement by gated radionuclide angiography.

To test the hypothesis that, after anesthesia for noncardiac surgical procedures, the increased cardiac work during recovery induces wall motion and ejection fraction (EF) abnormalities in patients with mild angina pectoris, gated radionuclide angiography was performed in patients undergoing simple cholecystectomy under narcotic-relaxant general anesthesia. The ejection fraction was determined during anesthesia at the end of surgery, and then determined 3 min and 3 hr after extubation. A new angiography was performed 24 hr later, and a myocardial scintigraphy (Thallium 201) was performed during infusion of the coronary vasodilator, dipyridamole.

Value of the 99mTc-methylene diphosphonate bone scan in renal osteodystrophy.

The value of radionuclide bone scanning in the diagnosis of renal osteodystrophy is still debated. In order to re-examine this issue, 25 uremic patients treated by intermittent hemodialysis underwent 99m-Technetium Methylene Diphosphonate (99mTc-MDP) bone scan. They were subdivided into three groups according to quantitative bone histology.

Left ventricular dysfunction after non-cardiac surgical procedures in patients with ischemic heart disease.

In order to demonstrate the presence of postischemic ventricular dysfunction after non-cardiac surgical procedures, myocardial perfusion scintigraphy with thallium 201 and radionuclide ventriculography were performed before and 24 h after intervention in 20 patients suffering from angina pectoris. A long-term ECG recording was used in all patients to detect peroperative myocardial ischemia. In 14 of the 20 patients studied, both ventriculography and thallium scintigraphy were unchanged at the postoperative study.

Limitations of fluorocarbons in reducing myocardial infarct size.

The effects of the oxygen-carrier fluorocarbons on myocardial infarct size were assessed in non-exchange-transfused dogs subjected either to a 3-hour occlusion of the left anterior descending coronary artery (LAD) followed by 2 hours of reperfusion (protocol I) or to a 5-hour permanent LAD occlusion (protocol II). Fluorocarbon administration was begun 30 minutes after LAD occlusion and was continued over the entire period of ischemia. After 5 hours, the hearts were excised and areas of necrosis were visualized by triphenyl tetrazolium chloride staining while risk regions were assessed by radiolabeled microspheres injected after coronary occlusion just before the onset of therapy, and further, in protocol I, by thallium-201 perfusion imaging performed at the end of fluorocarbon administration.

[Ileal duplication in adults. Value of 99m pertechnetate scintigraphy].

Duplications of the small bowel are an uncommon group of congenital malformations whose symptoms rarely occur in adults. We report the case of a 21 year-old man who suffered during four years from symptoms related to the ulceration of ectopic gastric mucosa in an ileal duplication (spontaneously resolving peritonitis, pelvic abscess, recurrent gastrointestinal bleeding and chronic abdominal pain). Radiological and endoscopic explorations and a first laparotomy failed to provide the diagnosis.

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.

Reduction of myocardial infarct size by a fluorocarbon-oxygenated reperfusate.

This investigation assesses whether the size of an acutely revascularized myocardial infarct (MI) could be reduced by altering the composition of the initial reperfusate. Nineteen open-chest dogs underwent 4-hour occlusion of the left anterior descending coronary artery and were then assigned to a treatment group: 12 dogs to selective intracoronary infusion of the modified reperfusate over 30 minutes before resumption of blood flow for 60 minutes and 7 to a control group (90 minutes of unmodified blood reperfusion). The modified reperfusate consisted of 500 ml of a fluorocarbon-oxygenated crystalloid solution (PO2 650 mm Hg; total O2 content 5.

Retrograde coronary sinus perfusion: a safe alternative for ensuring cardioplegic delivery in aortic valve surgery.

During aortic valve surgery, cardioplegic solution is delivered through direct cannulation of both coronary ostia. Since this approach may cause an intimal injury leading to acute dissection or late ostial stenosis, we have evaluated retrograde coronary sinus perfusion (RCSP) as a means of delivering cardioplegia in 12 patients undergoing aortic valve replacement. The retroperfusion of the cardioplegic solution was performed with a balloon-tipped catheter inserted into the coronary sinus through the right atrium.

[Nuclear magnetic resonance. Applications to medicine and biology (author's transl)].

Nuclear magnetic resonance (NMR) is a non-invasive exploratory technique based on a principle radically different from those of radiography, radionuclide exploration and ultrasonography. Signals coming from atomic nuclei and reflecting their density and chemical/biochemical environment are collected, thus providing information of the physiological and pathological state of tissues. The technique has multiple applications, either practical (tomographic imaging of the brain, thyroid gland and liver) or in the field of research, e.

Nuclear magnetic resonance: a new method for non-invasive assessment of cardiac metabolism.

In the setting of cardiac testing, NMR spectroscopy should occupy a major place since it allows a noninvasive serial assessment of the biochemical status of a functioning heart and could be coupled with other investigations to provide simultaneous recordings of both metabolic and functional data from a definite myocardial area. In the future, NMR imaging may become a clinically viable tool providing localized non-invasive biochemical measurements in the heart.

[Infra-radiographic decalcifying algodystrophy of the lower limb].

The authors have only reported cases responding to the following criteria: A) necessarily: 1) Clinical appearance of algodystrophy. 2) Intense hyperfixation of the bone scan. 3) X rays repeated a sufficient number of times always normal and submitted to the judgement of six rheumatologists not forewarned, to eliminate the subjective factor in the diagnosis of normality.

Effect of parathyroidectomy on left-ventricular function in haemodialysis patients.

The effect of parathyroidectomy on left-ventricular function was evaluated in chronic-haemodialysis patients with advanced hyperparathyroidism. Radionuclide angiocardiography (22 patients) and ultrasound echography (8 patients) revealed a significant increase in left-ventricular ejection fraction 1--2 weeks after parathyroidectomy. This improvement was associated with an augmented cardiac index (radionuclide method) and with an increase in mean velocity of circumferential myocardial fibre shortening (echocardiography).

[Medical applications of cyclotrons (author's transl)].

Isochronous cyclotrons used to accelerate different charge particles (protons, deuterons, alphas...