Validation of a volumic reconstruction in 4-d echocardiography and gated SPECT using a dynamic cardiac phantom.

A dynamic cardiac phantom was used as a reference to compare the volumes reconstructed with 4-D echocardiography and gated single-photon emission computed tomography (SPECT). 4-D echocardiography used a new prototype of rotating scan head to acquire ultrasound (US) images during a cardiac cycle, associated with a new protocol (left ventricular 4-D or LV 4-D) to reconstruct the volume deformations of the heart as a function of time. Gated SPECT data were acquired with a standard single-head gamma camera, and the reconstructions were carried out using the Mirage software released by Segami. The influences of different LV 4-D parameters were tested and analyzed. End-diastolic volume, end-systolic volume, and ejection fraction were measured using both LV 4-D and gated SPECT. Results obtained showed a straight correlation between the two examinations. The agreement confirmed the relevance of the comparisons. This study is an initial step before conducting clinical trials to exhaustively compare the two modalities.

Internal radiation therapy for hepatocellular carcinoma. Results of a French multicenter phase II trial of transarterial injection of iodine 131-labeled Lipiodol.

Preliminary Phase I trials have shown iodine 131 (131I)-Lipiodol (ethiodized oil; Laboratoires Guerbet, Aulnaysous-Bois, France) to be well tolerated and most likely effective in the treatment of hepatocellular carcinoma (HCC). In this multicenter Phase II trial, the authors tested the feasibility and reproducibility of this treatment in other medical institutions and evaluated its efficacy in 50 patients with unresectable Stage I or II HCC, by the classification of Okuda et al. The authors studied 47 men and 3 women (63.9 +/- 7.1 years old) with Stage I (n = 18) or II (n = 32) HCC, by the classification of Okuda et al., which was verified by histologic findings (n = 25), cytologic findings (n = 11), or association of a tumor with alpha-fetoprotein serum values greater than 500 micrograms/l (n = 14). This multicenter trial (1) confirmed that the 131I-Lipiodol treatment is well tolerated; (2) showed that there is a high reproducibility of results with respect to other institutions and an objective tumor response in 40% of the cases; and (3) indicated the necessity of performing a randomized controlled study.

[Functional coronary insufficiency in pheochromocytoma. Contribution of isotopic tests. A case report]. / L'insuffisance coronarienne fonctionnelle du phéochromocytome. Apport des examens isotopiques. A propos d'un cas.

A 67 year old woman with a right adrenal pheochromocytoma was admitted to hospital with decompensated diabetes. She developed clinical signs of myocardial infarction. Complementary investigations showed this to be an adrenergic cardiomyopathy. The radionuclide and angiographic investigations confirmed the ischemic origin of the lesions and the functional nature of the coronary insufficiency in this case of pheochromocytoma.

Time course localization of immunoglobulin M monoclonal antibody and its fragments in leukemic tumor-bearing mice.

In vivo localization of a mouse monoclonal antibody (F2-10.23 IgM) binding leukemic L 1210 cells was studied in DBA/2 mice bearing an L 1210 tumor. F(ab')2 fragments were prepared and their specific binding to L 1210 cells was analyzed by flow cytofluorometry. Radio-localization studies were performed by using 125I- or 131I-labeled IgM monoclonal antibody or its F(ab')2 fragments to ascertain their capacity to visualize the L 1210 tumor. F(ab')2 fragments were cleared more rapidly than the whole IgM; the clearance was as fast in healthy as in tumor-bearing mice. The tumor-to-muscle ratio observed 24 h after injection of 125I-radiolabeled F(ab')2 fragments and 125I-radiolabeled IgM was 10; the radioactivity level in the blood with F(ab')2 fragments was lower than with IgM, and so gamma-camera imaging was workable with F(ab')2 fragments without background subtraction. The tumor localization was studied over a period of 5 days by recording the distribution of the iodinated fragments in the tumor-bearing leg compared with that in the normal leg, and by computer analysis of the region of interest. F(ab')2 fragments gave better results than intact IgM in tumor visualization. Nevertheless, the rapid clearance of this antibody or its F(ab')2 fragments make them hardly suitable as carriers of toxic drugs.

Tumor localization of Lewis lung carcinoma with radiolabeled monoclonal antibodies.

Mouse 6D6 IgG2a and 5B5 IgM monoclonal antibodies which specifically bind murine lung carcinoma cells (3LL cells) were injected to healthy and tumor-bearing mice. In vivo localization was analyzed by counting the tissue radioactivity and by external gamma ray scintigraphy at various times after IV injection of 125I- or 131I-labeled antibodies. The clearance of the two monoclonal antibodies was not modified by the presence of the tumor, and the 6D6 IgG2a was cleared at a rate slower than the 5B5 IgM. Both antibodies gave a high specific uptake at the tumor level; the tumor-to-healthy tissue ratios were higher with the 6D6 IgG2a than the 5B5 IgM; unspecific mouse immunoglobulins (IgG2) did not localize in the tumor. The amount of 6D6 IgG2a antibody still associated with the tumor after 2 days following IV injection was 10 times higher than that of 5B5 IgM, and was still high enough to localize the tumor after 5 days. Imaging experiments confirmed the ability of 6D6 IgG2a to detect the presence of tumor cells. The targeting kinetics determined by computer analysis of camera images indicated a rapid targeting of antibodies in tumor with a maximal concentration after 4-6 h; after 48 h the background was quite low and the 6D6 IgG2a appeared to be specifically localized in the tumor.

The use of Kr-81m in ventilation imaging.

Radioactive gases are very useful in the study of pulmonary disorders because they allow an assessment of regional lung function. The most widely used radioactive gases are Xe-133 and, more recently, Kr-81m. This paper is a review of the physical characteristics of Kr-81m, its production from the parent Rb-81, the different methods to produce Rb-81, the different types of generators which can be used in hospitals, and the clinical applications of pulmonary ventilation imaging. The paper suggests that Kr-81m offers several advantages over previous methods that used Xe-133 due to its improved spatial resolution, its capacity to provide superimposable ventilation and perfusion images in multiple projections, and its total lung dose which is ten times lower than that of Xe-133.

[Late lymphedema in Turner's syndrome]. / Lymphoedeme tardif dans le syndrome de Turner.

Two cases of delayed unilateral lymphedema are reported in children presenting with Turner's syndrome. On this occasion, the frequency of lymphedema in Turner's syndrome and the more general problem of the lymphatic changes in this syndrome are discussed. The importance of isotopic lymphography is emphasized, because of its simplicity, its harmlessness and the good quality of the morphological and cinetic data obtained.

[The value of gallium 67 citrate in the diagnosis and localisation of deep-seated abdominal abscesses (author's transl)]. / Intérêt du citrate de gallium 67 dans le diagnostic et la localisation des abcès profonds de l'abdomen.

Six French Departments of Nuclear Medicine have pooled their results of Gallium 67 citrate scanning, carried out with the aim of demonstrating an abcess. Two hundred and thirty five examinations were performed. During the postoperative period, an abcess was correctly localised in 83 cases out of 89. For the 188 patients undergoing the examination, the reliability was 92%. In cases of suspicion of a subphrenic abcess, precise diagnosis was obtained in 19 cases out of 21. In 35 patients with an infectious syndrome in the absence of surgery, scanning gave an accurate diagnosis in 33. In 12 patients who had recently had a renal transplant, scanning revealed a purulent collection in 5 cases. By virtue of the affinity of Gallium for any inflammatory process, echotomography must always be performed after the isotope scan in order to confirm the presence or absence of a fluid collection in the region of the zone of increased uptake. These atraumatic techniques, easy to carry out, should provide clinicians with precious information when an infectious process within the abdomen is being sought.

[The measurement of total blood cell volume in newborns with respiratory distress]. / Interet de la mesure du volume globulaire total chez le nouveau-ne en detresse respiratoire.

The total blood cell volume was measured with 51Cr labelled red blood cells in 52 premature newborns, divided into 3 groups, with similar gestational ages and birth weigths: 15 controls, 11 children with transitory respiratory distress and 26 with hyaline membrane disease. The total red blood cell volumes were significantly different (p less than 0.001) in newborns with hyaline membrane disease (32.12 ml/kg +/- 8.75). No hypothesis explaining these results was satisfactory. However, early blood transfusion in children with hyaline membrane disease may be proposed as a practical application.

Reversible plasma and red blood cells volumes increases in acromegaly.

Plasma volume (PV) and red blood cells volume (RBCV) were measured in 76 normotensive acromegalic patients (42 males and 34 females) and compared with those of 28 controls on the basis of body surface. In untreated males PV and RBCV were significantly higher than in normals (P less than 0.001) and total blood volume (TBV) was above the normal range in 85%. Untreated females also showed an elevated PV but had significantly lower RBCV than the male patients. The only vascular volume of the patients with correlated significantly with the body weight or surface was RBCV in females. One to five studies were done after treatment in 52 patients and analyzed as a function of plasma GH levels. Plasma volume reverted to the normal range (males) or was significantly lower than in untreated patients (females) in the groups of patients with normal GH levels while RBCV normalized at higher GH concentrations. At similar GH levels, treated patients without pituitary failure (n = 35) or given T4 and/or cortisol substitution for hypopituitarism showed similar vascular volumes. The plasma volume and TBV in both sexes and RBCV in males was significantly correlated with Log 10 GH levels. It is concluded from these data and other experimental evidence that endogenous GH hypersecretion is responsible for the reversible PV and RBCV increases frequently found in acromegalic patients.

Comparative study of 111In and 59Fe bone marrow scanning.

The aim of this work is to examine the relative merits of 59Fe and 111In scanning in estimating the functional value of the various erythropoietic areas and in appraising bone marrow distribution and extension. At first we studied a group of patients with heterogeneous distribution of bone marrow secondary to irradiation, ferrokinetics serving a reference for the comparison of 111In and 59Fe scanning. The functional value fo 59Fe scanning was thus proved, in contrast to 111In scanning which was erroneous for 13 of the 29 bone marrow areas studied. A further study of patients presenting polycythemia vera or anemia with 111In demonstrated in some cases false distribution and bone marrow extension. Furthermore, 59Fe scanning permitted evaluation of the efficiency of erythropoiesis and the existence of extramedullary erythropoiesis. Review of the literature revealed that with the activity used there was no dosimetric advantage of 111In over 59Fe.