Gallium-67 scanning in the staging of cryptogenetic fibrosing alveolitis and hypersensitivity pneumonitis.

Gallium-67 citrate is known to localize within inflammatory sites. Gallium-67 scanning is used for the evaluation of lung inflammation (i.e. alveolitis) during interstitial lung diseases. We investigated 27 patients with cryptogenetic fibrosing alveolitis (n = 17) and hypersensitivity pneumonitis (n = 10) using gallium-67 lung scanning and lung function tests (forced vital capacity, diffusing capacity, resting and exercise blood gases). Investigations were performed before and after one year of methylprednisolone treatment. None of eight healthy volunteers had any abnormal gallium-67 uptake. In all patients with cryptogenetic fibrosing alveolitis an initial abnormal gallium-67 uptake was observed (mean fixation index: 163 +/- 18). In addition, analysis of lung function tests a year after initial evaluation showed that unchanged or improving patients presented initially with a lower gallium-67 index than patients with evidence of deterioration (153.9 +/- 23.7 vs 251.0 +/- 23.3.; p less than 0.01). Similarly, among patients with hypersensitivity pneumonitis the index was lower in unchanged or improving patients than in those with deterioration (74.9 +/- 22 vs 226.7 +/- 4.9; p less than 0.05). Thus gallium-67 scanning is useful in the management of cryptogenetic fibrosing alveolitis and hypersensitivity pneumonitis.

Pitfalls and solutions in neuroblastoma diagnosis using radioiodine MIBG: our experience about 50 cases.

We have been among the first authors to point out that false negative cases could be observed with 131I-MIBG scintigraphy for neuroblastoma. We have observed until now ten of such false negative cases, 7 with primary tumor and 3 with bone metastases. Fifty 131I-MIBG scans were performed in 35 children with histologically proven neuroblastoma (24 grade IV) and compared to bone scans, CT and NMR images, ultrasound and clinical results. The visualization of the primary tumor shows a higher sensitivity with MIBG (79%) than with bone scans (47%) and a 100% specificity with each method. MIBG and bone scans, for bone metastases, are similar in the sensitivity (87.5%) but MIBG is much more specific (100%) than bone scan (81%). These results clearly confirm the superiority of MIBG scan for detection of primary tumor as well as bone metastases. However, MIBG is not always the most appropriate investigation, as shown by 11 observed pitfalls. Ten false negative cases have been observed and must be considered: in five out of 10 cases, bone scans performed with 99m Tc-HMDP made the diagnosis (3/7 cases of primary tumor and 2/3 cases of bone metastases). Moreover, one case was not usable due to a large digestive uptake. Our aim is to understand the reasons of the false negative by a meticulous analysis of every single case. The optimal procedure for neuroblastoma diagnosis, extent and follow up clearly seems to be the following strategy: MIBG scan must be firstly performed; in case of non-demonstrative scan the bone scan, which is complementary, will greatly contribute to the diagnosis.

Serum levels of tumor markers and presence of human antimouse antibodies: implications for diagnosis and treatment with radiolabeled monoclonal antibodies.

Our study is based on 100 radioimmunodetections and five immunotherapies in 84 patients with advanced carcinomas. We used a monoclonal anti-CEA F(ab')2 and anti-CA 19.9 F(ab')2 antibody "cocktail" in 75% of the cases and monoclonal anti-alpha FP, anti-beta HCG, and OC 125 F(ab')2 antibodies in the other cases. In all cases, we determined plasma tumor marker levels immediately before imaging. The positivity of the scans was analyzed in relation to the levels of plasma markers. We found that the imaging should be planned only in the cases in which marker levels exceed minimum thresholds. We developed an enzymoimmunologic assay to measure antimouse antibodies. We found that patients who received monoclonal antibodies developed in the mouse produce such antimouse antibodies. The kinetics of this production are analyzed to define the optimal sequence for more than one administration of monoclonal antibodies.

Radionuclide bone imaging in diaphyseal aclasis with malignant change.

Chondrosarcoma is a rare complication in hereditary multiple exostoses. The six patients in this study have had a complete follow-up and constitute the largest group of such cases to have been studied so far. Five patients had histologic evidence of malignancy. Since histologic examination can be very difficult, any other diagnostic features, may it be clinical, radiologic, or scintigraphical, should be taken into account for early surgical treatment. Bone scintigraphic examination is a valuable adjunct to early diagnosis of malignant change by showing highest uptake in malignant areas. It is also very useful for posttherapeutic follow-up.

Examination and comparative study of a simple method to determine the left ventricular ejection fraction.

The authors developed a simple radioisotopic method for determining the left ventricular ejection fraction with 99mTc-labelled red blood cells. The semi-quantitative data is acquired at the equilibrium stage and gated to the ECG. The results of this atraumatic and reproducible isotopic determination of LVEF correlate statistically well those of echocardiography and left ventricular angiography.

The hyperactive halo as a sign of renal graft death in 99mTc-DTPA studies.

In scintigraphic studies of renal transplants the absence of renal perfusion and clearance have been demonstrated to have many possible pathologic etiologies, vascular obstructions, and rejections. Increased perinephric activity was suggested as a sign of renal infarction and its absence may indicate potential renal viability. A case is presented in which a hyperactive halo was seen when the graft was dying.

[Assessment of ejection fraction and left ventricular and diastolic volume by non-invasive methods: echocardiography and isotopic technics. Comparison with angiography in 30 patients]. / L'évaluation de la fraction d'éjection et du volume télédiastolique du ventricule gauche par les méthodes non invasives: échocardiographie et techniques isotopiques. Comparaison avec les données angiographiques à propos de 30 patients.

Three methods of measuring the ejection and the left ventricular end-diastolic volume were compared in 30 consecutive patients (all adults, 3 normal, 3 congestive cardiomyopathy, 6 mixed aortic valve disease, 9 pure aortic stenosis and 9 pure aortic incompetence). The haemodynamic and angiographical data was compared to the results of M-mode echocardiography and gammaangiocardiography. The global results of the ejection fractions were compared: angiography gave the lowest values (0,58 +/- 18). The non-invasive methods gave very similar results (0,67 +/- 15 for the echo and gammaangio). A better correlation was obtained in the group with pure aortic incompetence; the results in pure aortic stenosis were not reliable. The global results of end-diastolic volume showed constant underestimation by the non-invasive methods compared to angiography. The choice of method in each technique may influence the results obtained; each laboratory should determine its normal values; results should not be accepted without a critical assessment. Standardisation of techniques would be desirable.