[Neuroradiological investigations in mild brain injuries: state of the art and practical recommendations]. / La neuro-imagerie après traumatisme crânien léger: mise au point et recommandations pratiques.

OBJECTIVES: To clarify the contribution of each technique of neuroradiological and nuclear medicine investigations after mild brain injuries. To analyze the pathophysiological mechanisms of the lesions. To update indications for imaging techniques in the short or long term management. To define the practical recommendations. METHOD: The international databases were consulted for each neuroradiological technique; the most valuable articles were retained for study (PubMed, ). RESULTS AND DISCUSSION: Standard skull X-rays are obsolete. Craniofacial (bony windows) and brain CT-scan (parenchymal windows) is the most efficient diagnosis tool in the acute phase because of its accessibility. Brain MRI is less accessible in the emergency setting but is feasible in some centers. It is the best choice in the first weeks following mild brain injury but may be normal. Taking into account the limitations of morphological imaging, functional imaging techniques (SPECT, fMRI, PET-scan) are necessary as they may show axonal damage or brain atrophy. There is however the problem of availability. SPECT is the most accessible. Spectro-MRI is promising. In spite of progress in neuroradiological investigation methods, the neuropsychological evaluation and multi-disciplinary treatment of these patients by a skilled team remains of utmost importance.

Lung scintigraphy in postpneumonectomy dyspnea due to a right-to-left shunt.

We report the case of a 50-yr-old man who experienced exertional dyspnea 5 mo after a left pneumonectomy for carcinoma. As the clinical features pointed toward a pulmonary embolism, we performed a ventilation plus perfusion radionuclide lung scan. It showed no evidence of pulmonary embolism, but it did show a systemic uptake of the isotope, suggesting a right-to-left shunt that was confirmed by contrast echocardiography, which revealed an atrial septal defect. Right-to-left shunts after pneumonectomy have already been reported and can be diagnosed by lung scintigraphy. Usually, a patent foramen ovale is encountered, but the underlying physiopathology remains under discussion. Clinically, right-to-left shunts are often related to platypnea-orthodeoxia.

[Necessity of radiopharmaceutical control and vigilance]. / De la nécessité du contrôle radiopharmaceutique et d'une radiopharmaco-surveillance.

A recent problem with radiopharmaceutics in Val-de-Grâce hospital proves the necessity of a control. Using of the 99mTc (Hydroxy-methylene diphosphonate [HMDP] skeletal image we got a kidney scintigraphic images instead of the expected skeleted. The investigation of the occurrences has rapidly shown no possible confusion: At the day of failed examination, only 99mTc microspheres (target: Lung), methoxy-isobutyl-isonitrile, MIBI (target: heart) and 99mTc Phytate (target: Reticulo-Endothelial System) were used. Radioactivity control of 99mTc generator was conformable and labelled efficiency of the whole of HMDP assays were satisfying. This test is only an approach of radiochemical purity and was not adequate here. The renal image had suggested a chelate use. Accordingly, we have realized the Pharmacopoeia identification of DTPA with dimethyl-glyoxime-Ni, HMDP standards, DTPA (diethylene-triamino pentacetate), and HMDP residues from the vials used on the incident's day. It has been shown that residues of HMDP contain, like DTPA, but not like HMDP standards, a nickel chelating system. This proves a substitution of compound unknown to medical users.

[Tuberculous reactions]. / Réactions tuberculiniques.

Intradermoreaction made with reliable tuberculin is the reference test: it is the only one that allows a therapeutic decision. The other tests can only be used as pre or post vaccinal tests, or as a technical approach for new born. In France, the reading of the IDR is difficult because BCG is almost always applied during small childhood. However it is possible to admit tuberculosis infection for vaccinated person with clear increase of the IDR positivity compared to a measured reference IDR, or when the IDR is superior to 14 mm for persons vaccinated a long time ago. For immunocompetent persons, a tuberculosis infection admitted on an isolated IDR (not associated with tuberculosis disease) does not need chimiprophylaxy for children under five, or in case of clear and recent increase of IDR, or in a context of contamination. For a HIV positive person, a tuberculosis infection admitted on an isolated IDR implies a systematic chimioprophylaxy, but the IDR looses its signification as the immunodepression progresses. An attempt to study the prevalence of tuberculosis infection at twenty in France for vaccinated persons has been realized. In 1984 the admitted rate is over 8%, superior to the calculated rate from Styblo and Sutherland tables. That seems to mean that tuberculosis infection is under evaluated in France.

[Left ventricular relaxation and hypertension. Effect of captopril on gamma-angiographic parameters]. / Relaxation ventriculaire gauche et hypertension artérielle effet du captopril sur les paramètres gamma-angiographiques.

In order to evaluate the action of captopril on left ventricular filling in hypertension, 14 hypertension (158 +/- 10/101 +/- 5 mmHg) patients aged 51 +/- 6 years were investigated by Technetium 99m gamma-angiography. The time/activity curve was used to determine the maximum filling rate (MFR) and maximum filling time (MFT) of the ventricle before and after treatment with captopril (mean dose : 44 +/- 26 mg/day for 7 months). Blood pressure was significantly lowered by treatment and there was a decrease in left ventricular mass from 128 +/- 17 to 118 +/- 15 g/m2 (p = 0.07). Maximum filling rate was accelerated by treatment from 2.27 +/- 0.57 to 2.57 +/- 0.43 VTD . s-1, p = 0.005). This variation was due essentially to half of the patients, suggesting an "all or nothing" type response. Maximum filling time did not vary. The basic question raised by this type of study is to know whether the improvement in the available relaxation parameter, MFR, was associated with actual improvement in filling, which is the true aim. Although the explanations offered for the observed findings are hypothetical, taking into account of all the trial data together with the morphological data provided by echocardiography suggests that captopril does have an actual and hemodynamically significant action on filling.

[Left ventricular filling and left bundle branch block: an echocardiographic and radionuclide study]. / Remplissage ventriculaire gauche et bloc de branche gauche: étude échocardiographique et isotopique.

Left bundle branch block changes the activation and haemodynamics of the left ventricle. In order to evaluate its consequences on left ventricular filling, the duration of the isovolumic relaxation period, the velocities and the integrals of the rapid and slow filling waves were recorded by Doppler echocardiography and the ejection fraction, the peak filling rate and its time of apparition were measured by gamma angiocardiography in 18 patients aged 55 +/- 9 years and 18 control subjects aged 53 +/- 9 years. Left bundle branch block was associated with a prolonged isovolumic relaxation period (104 +/- 14 vs 88 +/- 11 ms) a delayed and reduced peak filling rate and an increased atrial filling velocity at a heart rate comparable to that of control subjects (69 +/- 9 vs 72 +/- 8 beats/mn). Despite these changes in left ventricular relaxation and filling and a reduced ejection fraction (55 +/- 7 vs 61 +/- 6%, p < 0.01) cardiac output was not significantly decreased in left bundle branch block (4.9 +/- 1 vs 5.2 +/- 0.9 l/mn). Therefore, left bundle branch block interferes with left ventricular filling and ejection fraction without decreasing the resting enddiastolic volume.

[Normal aging, hypertension and left ventricular filling]. / Vieillissement naturel, hypertension artérielle et remplissage ventriculaire gauche.

Because of discrepancy in interpretation of early diastolic filling indices in normal subjects and hypertensive, we studied the correlations between age and radionuclide angiographic peak filling rate (PFR), doppler echocardiographic early E and late A waves, left ventricular mass (LVM), blood pressure (BP) and ejection fraction (EF) in cautiously screened 30 untreated hypertensive and 30 age paired normal subjects (mean of age 52 +/- 17 ranging from 34 to 78 years). No patient had gross obesity nor coronary artery disease. Univariate analysis revealed strong correlations between LV filling and age in normal (r = -0.82 p less than 0.0001) and hypertensive (r = -0.61 p less than 0.001), with a very significant difference in y intercepts (t = 0.61 p = 10(-6)). LVM correlated poorly with age (r = 0.35 p less than 0.05) but with none of the LV filling indexes. BP correlated with PFR (r = 0.33 p less than 0.05) and A wave (r = 0.44 p less than 0.02) in hypertensive only. After multivariate analysis, significant dependencies of PFR, age, LV mass were more accurate if BP was in a higher range. The variability of the values of LV filling indexes was wider in hypertensive than in normotensive. Normotensive aging and hypertension have similar effects on the cardiovascular system. In the most aged people even without apparent cardiac disease, it is not possible to identify the specific effects of hypertension on diastolic function.

Evaluation of residual masses after lymphoma treatment: the contribution of gallium 67 tomoscintigraphy.

19 tomoscintigraphies using gallium 67 were performed in 15 patients with Hodgkin's or non-Hodgkin's lymphoma who had a residual mass after treatment. The isotope was never fixed in fibrous masses but was always concentrated in actively growing masses. In five cases histology confirmed these findings. It is recommended that scintigraphy should be considered in every case with a residual mass after treatment, where a decision regarding further treatment is required.

[Exploration of left ventricular relaxation using gamma-angiography in 70 hypertensive subjects. Practical consequences and implications]. / Exploration de la relaxation ventriculaire gauche par gamma-angiographie chez soixante-dix hypertendus. Implications et conséquences pratiques.

This study was performed to evaluate the incidence ant the practical consequences of left ventricular diastolic dysfunction in hypertensive. In 70 mild to moderate hypertensive subjects group [systolic 161 +/- 16 and diastolic blood pressure 104 +/- 9 mmHg 18 women, 52 men, 51 +/- 7 years old] and in a 15 normal subjects control group, the peak filling rate (PFR) and the time to peak filling rate (TPFR) were measured with the time/activity curve of the rest equilibrium blood pool scintigraphy. The ejection fraction and the stress test were normal in all patients [EF 0.66 +/- 0.05, ranging from 0.59 to 0.88]. The PFR was not significantly different in the hypertensive group but 59/70 patients [84 p. 100] showed an individual value lower than the theoretical age and heart rate expected value. The TPFR was not significantly different (183 +/- 33 ms-vs 180, p = ns). In a Holter-defined sub-group of patients (n = 22) exhibiting a high prevalence of supra-ventricular premature beats or a paroxysmal atrial fibrillation, the PFR was significantly slower than in the total hypertensive group [1.92 +/- 0.33 EDV/s-1, p = 0.02]. Early indices of diastolic function give some instantaneous information on left ventricular filling. Determining the exact significance of individual values of PFR and TPFR requires a better knowledge of physiologic and pathologic determinants of LV filling.